Merge pull request 'feat/30-cgats-interop' (#56) from feat/30-cgats-interop into milestone/m6-gamut-stage0-cgats-release

- Add CGATSParser, CGATSWriter, and CGATSSummary under ICCeryCore/CGATS.
- Parse CTI3, CGATS.17, ISO28178, and CSV; synthesize COLOR_REP/DEVICE_CLASS.
- Scale RGB/CMYK device coordinates from 0-255 to 0-100 when needed.
- Round-trip parse, write, reparse with tab-delimited canonical .ti3.
- Wire `Import Dataset…` in Stage 1 to open-panel import, write .ti3, and
  jump to Stage 4/5 while keeping Stages 1-2 locked without .ti1/.ti2.
- Add CGATSParserTests and Milestone6CGATSUITests.importUsesOpenPanelNotSaveTi1.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

Packages/ICCeryCore/Sources/ICCeryCore/Argyll/ArgyllRunner.swift

@@ -0,0 +1,800 @@
+import Foundation
+
+/// Errors from `ArgyllRunner` executions.
+public enum ArgyllRunnerError: LocalizedError, Equatable, Sendable {
+    case processFailed(code: Int32, logs: [String])
+    case missingArtefact(String)
+    case malformedManifest(String)
+    case instrumentDetectionFailed(String)
+    case chartreadFailed(String)
+    case averageFailed(String)
+    case colprofFailed(String)
+    case applycalFailed(String)
+    case iccgamutFailed(String)
+    case profcheckFailed(String)
+    case profcheckUnparseable
+
+    public var errorDescription: String? {
+        switch self {
+        case .processFailed(let code, _):
+            return "Process exited with code \(code)"
+        case .missingArtefact(let path):
+            return "Expected output file was not created: \(path)"
+        case .malformedManifest(let reason):
+            return "Failed to parse printtarg manifest: \(reason)"
+        case .instrumentDetectionFailed(let reason):
+            return "Instrument detection failed: \(reason)"
+        case .chartreadFailed(let reason):
+            return "Chartread failed: \(reason)"
+        case .averageFailed(let reason):
+            return "Averaging failed: \(reason)"
+        case .colprofFailed(let reason):
+            return "Profile creation failed: \(reason)"
+        case .applycalFailed(let reason):
+            return "Apply calibration failed: \(reason)"
+        case .iccgamutFailed(let reason):
+            return "Gamut extraction failed: \(reason)"
+        case .profcheckFailed(let reason):
+            return "Profile verification failed: \(reason)"
+        case .profcheckUnparseable:
+            return "Profile verification produced unparseable output"
+        }
+    }
+}
+
+/// Result of a successful `printtarg` run: the `.ti2` artefact plus the
+/// validated manifest with per-page PNG previews already decoded.
+public struct PrinttargResult: Sendable, Equatable {
+    public let ti2URL: URL
+    public let manifest: PrinttargManifest
+    public let pages: [GalleryPage]
+}
+
+/// Service driving Argyll subprocesses off the main actor
+/// (docs/03, docs/08, docs/09).
+///
+/// - Subscribes to the event bus *before* spawning so no stdout or exit
+///   is ever lost (subscription is synchronous in `ProcessManager`).
+/// - Accumulates stdout/stderr without touching `@MainActor`; the
+///   optional `onLogBatch` callback receives coalesced chunks (20 lines
+///   or ~100 ms), never one call per line.
+/// - Exit code 0 is necessary but not sufficient: the expected artefact
+///   (`.ti1` / `.ti2`) must exist on disk, and printtarg must emit a
+///   valid `-u` manifest.
+public struct ArgyllRunner: Sendable {
+    public let processManager: ProcessManager
+    public let binaryResolver: BinaryResolver
+
+    public init(
+        processManager: ProcessManager = .shared,
+        binaryResolver: BinaryResolver = BinaryResolver()
+    ) {
+        self.processManager = processManager
+        self.binaryResolver = binaryResolver
+    }
+
+    // MARK: - targen (Stage 1)
+
+    /// Runs `targen` streaming, collecting logs and verifying `.ti1`
+    /// upon completion. Returns the `.ti1` URL.
+    public func runTargen(
+        config: TargenConfig,
+        onLogBatch: (@Sendable ([String]) -> Void)? = nil
+    ) async throws -> URL {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+        let cwd = PathSecurity.resolveSafeCwd(config.workingDirectory)
+        let args = try TargenArgs.build(config: config)
+        let binaryURL = binaryResolver.resolve("targen")
+        let processId = ProcessID.targen(cleanBasename)
+
+        await ensureNotRunning(id: processId)
+        let events = processManager.events()
+        try await processManager.runStreaming(
+            id: processId,
+            binary: binaryURL,
+            arguments: args,
+            workingDirectory: cwd
+        )
+        let run = await collect(id: processId, events: events, onLogBatch: onLogBatch)
+
+        guard run.exitCode == 0 else {
+            throw ArgyllRunnerError.processFailed(code: run.exitCode ?? -1, logs: run.lines)
+        }
+        let ti1URL = cwd.appendingPathComponent("\(cleanBasename).ti1")
+        guard FileManager.default.fileExists(atPath: ti1URL.path) else {
+            throw ArgyllRunnerError.missingArtefact(ti1URL.path)
+        }
+        return ti1URL
+    }
+
+    // MARK: - printtarg (Stage 2)
+
+    /// Runs `printtarg` streaming, then parses the `-u` manifest from
+    /// the complete accumulated stdout and loads each page's PNG
+    /// preview via `TiffPreview` (host-side, never raw TIFF to the UI).
+    public func runPrinttarg(
+        config: PrinttargConfig,
+        onLogBatch: (@Sendable ([String]) -> Void)? = nil
+    ) async throws -> PrinttargResult {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+        let cwd = PathSecurity.resolveSafeCwd(config.workingDirectory)
+        let args = try PrinttargArgs.build(config: config)
+        let binaryURL = binaryResolver.resolve("printtarg")
+        let processId = ProcessID.printtarg(cleanBasename)
+
+        await ensureNotRunning(id: processId)
+        let events = processManager.events()
+        try await processManager.runStreaming(
+            id: processId,
+            binary: binaryURL,
+            arguments: args,
+            workingDirectory: cwd
+        )
+        let run = await collect(id: processId, events: events, onLogBatch: onLogBatch)
+
+        guard run.exitCode == 0 else {
+            throw ArgyllRunnerError.processFailed(code: run.exitCode ?? -1, logs: run.lines)
+        }
+        let ti2URL = cwd.appendingPathComponent("\(cleanBasename).ti2")
+        guard FileManager.default.fileExists(atPath: ti2URL.path) else {
+            throw ArgyllRunnerError.missingArtefact(ti2URL.path)
+        }
+
+        let manifest: PrinttargManifest
+        do {
+            manifest = try PrinttargManifestExtractor.manifest(from: run.stdout)
+        } catch {
+            throw ArgyllRunnerError.malformedManifest(error.localizedDescription)
+        }
+
+        let pages = manifest.pages.enumerated().map { index, page -> GalleryPage in
+            let fileURL = cwd.appendingPathComponent(page.filename)
+            guard FileManager.default.fileExists(atPath: fileURL.path) else {
+                return GalleryPage(
+                    index: index, page: page, fileURL: fileURL,
+                    previewPNG: nil, previewError: "File not found"
+                )
+            }
+            if let png = TiffPreview.previewPNG(tiff: fileURL) {
+                return GalleryPage(
+                    index: index, page: page, fileURL: fileURL,
+                    previewPNG: png, previewError: nil
+                )
+            }
+            return GalleryPage(
+                index: index, page: page, fileURL: fileURL,
+                previewPNG: nil, previewError: "Could not decode TIFF"
+            )
+        }
+        return PrinttargResult(ti2URL: ti2URL, manifest: manifest, pages: pages)
+    }
+
+    // MARK: - Shared collection
+
+    /// Cancels any previous child with the same id and waits for it to
+    /// finalize, so `runStreaming` / `runCaptured` never sees a
+    /// `duplicateID` from a leftover process (#50, #52).
+    private func ensureNotRunning(id: String) async {
+        guard await processManager.isRunning(id) else { return }
+        await processManager.kill(id: id)
+        var attempts = 0
+        while await processManager.isRunning(id), attempts < 30 {
+            try? await Task.sleep(for: .milliseconds(100))
+            attempts += 1
+        }
+    }
+
+    private struct CollectedRun {
+        var exitCode: Int32?
+        var stdout: String
+        var stderr: String
+        var lines: [String]
+    }
+
+    /// Drains the event stream until this child's `exit` event.
+    /// stdout is accumulated both per-line (logs) and verbatim (for
+    /// the manifest parse — the pretty JSON needs its newlines).
+    ///
+    /// When `flushPartialLines` is `true`, a background `Task` flushes
+    /// unterminated output every 500 ms so tools like `colprof` that
+    /// print dots without newlines still produce log batches.
+    private func collect(
+        id processId: String,
+        events: AsyncStream<ProcessEvent>,
+        onLogBatch: (@Sendable ([String]) -> Void)?,
+        flushPartialLines: Bool = false
+    ) async -> CollectedRun {
+        var lines: [String] = []
+        var stdout = ""
+        var stderr = ""
+        var pendingBatch: [String] = []
+        var exitCode: Int32?
+        var lastFlush = Date()
+
+        func flush(_ batch: inout [String]) {
+            guard !batch.isEmpty else { return }
+            let out = batch
+            batch.removeAll(keepingCapacity: true)
+            onLogBatch?(out)
+        }
+
+        var dotFlushTask: Task<Void, Never>?
+        if flushPartialLines {
+            dotFlushTask = Task { [processManager] in
+                while !Task.isCancelled {
+                    try? await Task.sleep(for: .milliseconds(500))
+                    if Task.isCancelled { break }
+                    await processManager.flushPartialLine(id: processId)
+                }
+            }
+        }
+
+        for await event in events {
+            guard event.id == processId else { continue }
+            switch event {
+            case .stdout(_, let line):
+                lines.append(line)
+                stdout += line + "\n"
+                pendingBatch.append(line)
+            case .stderr(_, let line):
+                lines.append(line)
+                stderr += line + "\n"
+                pendingBatch.append(line)
+            case .error(_, let message):
+                lines.append("Error: \(message)")
+                pendingBatch.append("Error: \(message)")
+            case .jsonRow:
+                // Only chartread emits these; targen/printtarg never do.
+                break
+            case .exit(_, let code):
+                exitCode = code
+            }
+            if exitCode == nil,
+               pendingBatch.count >= 20
+                || Date().timeIntervalSince(lastFlush) >= 0.1 {
+                flush(&pendingBatch)
+                lastFlush = Date()
+            }
+            if exitCode != nil {
+                flush(&pendingBatch)
+                break
+            }
+        }
+
+        dotFlushTask?.cancel()
+        if let dotFlushTask {
+            _ = await dotFlushTask.value
+        }
+
+        return CollectedRun(exitCode: exitCode, stdout: stdout, stderr: stderr, lines: lines)
+    }
+
+    // MARK: - instlist (Stage 3 detection)
+
+    /// Runs `instlist` and returns the detected devices.
+    ///
+    /// The fork emits pretty-printed JSON; if that cannot be decoded a regex
+    /// fallback constrained to known instrument tokens is used.
+    public func detectInstruments() async throws -> [InstrumentDevice] {
+        let binaryURL = binaryResolver.resolve("instlist")
+        let processId = ProcessID.instlist
+
+        await ensureNotRunning(id: processId)
+        let events = processManager.events()
+        try await processManager.runStreaming(
+            id: processId,
+            binary: binaryURL,
+            arguments: [],
+            workingDirectory: nil
+        )
+
+        var accumulator = JSONAccumulator()
+        var stdout = ""
+        var stderr: [String] = []
+        var exitCode: Int32?
+
+        for await event in events {
+            guard event.id == processId else { continue }
+            switch event {
+            case .stdout(_, let line):
+                stdout += line + "\n"
+                _ = accumulator.feed(line: line)
+            case .stderr(_, let line):
+                stderr.append(line)
+            case .exit(_, let code):
+                exitCode = code
+            default:
+                break
+            }
+            if exitCode != nil { break }
+        }
+
+        if let data = accumulator.completeData ?? stdout.trimmingCharacters(in: .whitespacesAndNewlines).data(using: .utf8) {
+            if let devices = try? InstrumentParser.parse(String(data: data, encoding: .utf8) ?? stdout) {
+                return devices
+            }
+        }
+
+        if let code = exitCode, code != 0, stderr.isEmpty == false {
+            throw ArgyllRunnerError.instrumentDetectionFailed(stderr.joined(separator: "\n"))
+        }
+
+        // Final fallback: try to parse the raw stdout as a text document.
+        if let devices = try? InstrumentParser.parse(stdout) {
+            return devices
+        }
+
+        throw ArgyllRunnerError.instrumentDetectionFailed("Could not parse instlist output")
+    }
+
+    // MARK: - average (Stage 3 multi-pass finish)
+
+    /// Runs `average` to merge two or more pass snapshots into the canonical `.ti3`.
+    public func runAverage(
+        config: AverageConfig,
+        onLogBatch: (@Sendable ([String]) -> Void)? = nil
+    ) async throws -> URL {
+        let cwd = PathSecurity.resolveSafeCwd(config.workingDirectory)
+        let args = try AverageArgs.build(config: config)
+        let binaryURL = binaryResolver.resolve("average")
+        let processId = ProcessID.average(config.basename)
+
+        await ensureNotRunning(id: processId)
+        let events = processManager.events()
+        try await processManager.runStreaming(
+            id: processId,
+            binary: binaryURL,
+            arguments: args,
+            workingDirectory: cwd
+        )
+        let run = await collect(id: processId, events: events, onLogBatch: onLogBatch)
+
+        guard run.exitCode == 0 else {
+            throw ArgyllRunnerError.averageFailed("average exited with code \(run.exitCode ?? -1)")
+        }
+
+        let canonical = cwd.appendingPathComponent("\(config.basename).ti3")
+        guard FileManager.default.fileExists(atPath: canonical.path) else {
+            throw ArgyllRunnerError.missingArtefact(canonical.path)
+        }
+        return canonical
+    }
+
+    // MARK: - colprof (Stage 4)
+
+    /// Runs `colprof` streaming, collecting logs and classifying progress
+    /// until the profile is written.
+    public func runColprof(
+        config: ColprofConfig,
+        onLogBatch: (@Sendable ([String]) -> Void)? = nil
+    ) async throws -> URL {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+        let cwd = PathSecurity.resolveSafeCwd(config.workingDirectory)
+        let args = try ColprofArgs.build(config: config)
+        let binaryURL = binaryResolver.resolve("colprof")
+        let processId = ProcessID.colprof(cleanBasename)
+
+        await ensureNotRunning(id: processId)
+        let events = processManager.events()
+        try await processManager.runStreaming(
+            id: processId,
+            binary: binaryURL,
+            arguments: args,
+            workingDirectory: cwd
+        )
+        let run = await collect(
+            id: processId,
+            events: events,
+            onLogBatch: onLogBatch,
+            flushPartialLines: true
+        )
+
+        guard run.exitCode == 0 else {
+            throw ArgyllRunnerError.colprofFailed(
+                "colprof exited with code \(run.exitCode ?? -1)"
+            )
+        }
+
+        // Argyll may produce `.icm` on Windows, but on macOS we expect `.icc`.
+        // `resolveProfile` checks `.icm` first, then `.icc`, matching #69.
+        guard let profileURL = ArtefactProbe.resolveProfile(
+            basename: cleanBasename,
+            cwd: cwd
+        ) else {
+            let defaultURL = cwd.appendingPathComponent("\(cleanBasename).icc")
+            throw ArgyllRunnerError.missingArtefact(defaultURL.path)
+        }
+        return profileURL
+    }
+
+    // MARK: - applycal (post-colprof calibration curve)
+
+    /// Embeds a `.cal` curve into an `.icc`/`.icm` profile.
+    ///
+    /// Runs `applycal` captured and performs an in-place replace via
+    /// `{input}.applycal.tmp` then `replaceItemAt`. On failure the tmp
+    /// file is removed and the original is left untouched. The UI must
+    /// never request `unapply` (#52).
+    public func runApplycal(
+        config: ApplycalConfig
+    ) async throws -> URL {
+        assert(!config.unapply, "runApplycal does not support unapply")
+
+        let inputURL = config.inputProfileURL
+        let cwd = inputURL.deletingLastPathComponent()
+        let binaryURL = binaryResolver.resolve("applycal")
+        let processId = ProcessID.applycal(inputURL.lastPathComponent)
+
+        let tmpURL = inputURL.appendingPathExtension("applycal.tmp")
+        let fm = FileManager.default
+
+        // Remove any stale tmp from a previous crash.
+        try? fm.removeItem(at: tmpURL)
+
+        await ensureNotRunning(id: processId)
+
+        let outputConfig = ApplycalConfig(
+            calibrationPath: config.calibrationPath,
+            inputProfileURL: inputURL,
+            outputProfileURL: tmpURL,
+            unapply: false
+        )
+        let outputArgs = try ApplycalArgs.build(config: outputConfig)
+
+        let result = try await processManager.runCaptured(
+            id: processId,
+            binary: binaryURL,
+            arguments: outputArgs,
+            workingDirectory: cwd
+        )
+
+        guard result.exitCode == 0, !Task.isCancelled else {
+            try? fm.removeItem(at: tmpURL)
+            if Task.isCancelled {
+                throw CancellationError()
+            }
+            throw ArgyllRunnerError.applycalFailed(
+                result.stderr.isEmpty
+                    ? "applycal exited with code \(result.exitCode)"
+                    : result.stderr
+            )
+        }
+
+        guard fm.fileExists(atPath: tmpURL.path) else {
+            throw ArgyllRunnerError.applycalFailed(
+                "applycal did not create temp profile"
+            )
+        }
+
+        let attrs = try? fm.attributesOfItem(atPath: tmpURL.path)
+        let size = attrs?[.size] as? UInt64 ?? 0
+        guard size >= 128 else {
+            try? fm.removeItem(at: tmpURL)
+            throw ArgyllRunnerError.applycalFailed(
+                "calibrated profile is too small (\(size) bytes)"
+            )
+        }
+
+        do {
+            if fm.fileExists(atPath: inputURL.path) {
+                _ = try fm.replaceItemAt(inputURL, withItemAt: tmpURL)
+            } else {
+                try fm.moveItem(at: tmpURL, to: inputURL)
+            }
+        } catch {
+            try? fm.removeItem(at: tmpURL)
+            throw ArgyllRunnerError.applycalFailed(error.localizedDescription)
+        }
+
+        return inputURL
+    }
+
+    // MARK: - iccgamut (post-colprof gamut mesh)
+
+    /// Extracts a `.gam` mesh from the finished profile.
+    public func runIccgamut(
+        config: IccgamutConfig,
+        onLogBatch: (@Sendable ([String]) -> Void)? = nil
+    ) async throws -> URL {
+        let profileURL = config.profileURL
+        let cwd = profileURL.deletingLastPathComponent()
+        let stem = profileURL.deletingPathExtension().lastPathComponent
+        let args = try IccgamutArgs.build(config: config)
+        let binaryURL = binaryResolver.resolve("iccgamut")
+        let processId = ProcessID.iccgamut(stem: stem)
+
+        await ensureNotRunning(id: processId)
+        let events = processManager.events()
+        try await processManager.runStreaming(
+            id: processId,
+            binary: binaryURL,
+            arguments: args,
+            workingDirectory: cwd
+        )
+        let run = await collect(id: processId, events: events, onLogBatch: onLogBatch)
+
+        guard run.exitCode == 0 else {
+            throw ArgyllRunnerError.iccgamutFailed(
+                "iccgamut exited with code \(run.exitCode ?? -1)"
+            )
+        }
+
+        let gamURL = cwd.appendingPathComponent("\(stem).gam")
+        guard FileManager.default.fileExists(atPath: gamURL.path) else {
+            throw ArgyllRunnerError.missingArtefact(gamURL.path)
+        }
+        return gamURL
+    }
+
+    // MARK: - profcheck (Stage 5 verification)
+
+    /// Verifies a profile against the canonical `.ti3`.
+    public func runProfcheck(
+        config: ProfcheckConfig,
+        onLogBatch: (@Sendable ([String]) -> Void)? = nil
+    ) async throws -> ProfcheckReport {
+        let cwd = config.ti3URL.deletingLastPathComponent()
+        let ti3Path = config.ti3URL.path
+
+        let iccURL = Self.resolveProfileForVerification(config.iccURL)
+        let config = ProfcheckConfig(ti3URL: config.ti3URL, iccURL: iccURL)
+
+        let args = try ProfcheckArgs.build(config: config)
+        let binaryURL = binaryResolver.resolve("profcheck")
+        let processId = ProcessID.profcheck(ti3Path: ti3Path)
+
+        await ensureNotRunning(id: processId)
+        let events = processManager.events()
+        try await processManager.runStreaming(
+            id: processId,
+            binary: binaryURL,
+            arguments: args,
+            workingDirectory: cwd
+        )
+        let run = await collect(id: processId, events: events, onLogBatch: onLogBatch)
+
+        guard run.exitCode == 0 else {
+            throw ArgyllRunnerError.profcheckFailed(
+                run.stderr.isEmpty
+                    ? "profcheck exited with code \(run.exitCode ?? -1)"
+                    : run.stderr
+            )
+        }
+
+        let output = (run.stdout + "\n" + run.stderr).trimmingCharacters(in: .whitespacesAndNewlines)
+        let report = ProfcheckParser.parse(output)
+        guard report.isValid else {
+            throw ArgyllRunnerError.profcheckUnparseable
+        }
+        return report
+    }
+
+    private static func resolveProfileForVerification(_ url: URL) -> URL {
+        let fm = FileManager.default
+        if fm.fileExists(atPath: url.path) { return url }
+        let alt = url.pathExtension.lowercased() == "icc"
+            ? url.deletingPathExtension().appendingPathExtension("icm")
+            : url.deletingPathExtension().appendingPathExtension("icc")
+        return fm.fileExists(atPath: alt.path) ? alt : url
+    }
+
+    // MARK: - chartread (Stage 3 interactive)
+
+    /// Runs `chartread` and returns an `AsyncStream` of typed events.
+    ///
+    /// Subscribe-before-spawn, prompt/row/log forwarding, and exit verification
+    /// are all handled here. Use `sendChartreadInput` to drive the child and
+    /// `cancelChartread` to terminate it.
+    public func runChartread(config: ChartreadConfig) -> AsyncStream<ChartreadEvent> {
+        let cleanBasename: String
+        let cwd: URL
+        do {
+            cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+            cwd = PathSecurity.resolveSafeCwd(config.workingDirectory)
+        } catch {
+            return AsyncStream { continuation in
+                continuation.yield(.failed(ArgyllRunnerError.chartreadFailed(error.localizedDescription)))
+                continuation.finish()
+            }
+        }
+
+        let args: [String]
+        do {
+            args = try ChartreadArgs.build(config: config)
+        } catch {
+            return AsyncStream { continuation in
+                continuation.yield(.failed(ArgyllRunnerError.chartreadFailed(error.localizedDescription)))
+                continuation.finish()
+            }
+        }
+
+        let binaryURL = binaryResolver.resolve("chartread")
+        let processId = ProcessID.chartread(cleanBasename)
+        let processManager = self.processManager
+        let isXY = config.isXY
+
+        return AsyncStream { continuation in
+            let task = Task {
+                await ensureNotRunning(id: processId)
+                let events = processManager.events()
+
+                // Register the XY parking hook before spawning.
+                await processManager.setPreKillHook(id: processId) { [processManager] in
+                    if isXY {
+                        try? await processManager.sendStdin(id: processId, bytes: ChartreadInput.quit.bytes)
+                        try? await Task.sleep(for: .milliseconds(500))
+                    }
+                }
+
+                do {
+                    try await processManager.runStreaming(
+                        id: processId,
+                        binary: binaryURL,
+                        arguments: args,
+                        workingDirectory: cwd
+                    )
+                } catch {
+                    continuation.yield(.failed(ArgyllRunnerError.chartreadFailed(error.localizedDescription)))
+                    continuation.finish()
+                    return
+                }
+
+                var state: ChartreadState = .idle
+                var pendingLogs: [String] = []
+                var lastFlush = Date()
+                var exitCode: Int32?
+
+                func flushLogs() {
+                    guard !pendingLogs.isEmpty else { return }
+                    let batch = pendingLogs
+                    pendingLogs.removeAll(keepingCapacity: true)
+                    continuation.yield(.log(batch))
+                }
+
+                for await event in events {
+                    guard event.id == processId else { continue }
+
+                    switch event {
+                    case .stdout(_, let line):
+                        let previous = state
+                        let classified = ChartreadClassifier.classify(line: line, previousState: previous)
+                        state = classified.state
+
+                        if classified.isRemoveSheetNotice {
+                            continuation.yield(.removeSheetNotice)
+                        }
+
+                        let shouldPrompt =
+                            classified.sheetNumber != nil
+                            || classified.alignmentPatch != nil
+                            || classified.requestedWarningKey != nil
+                            || classified.state != previous
+                            || classified.isTableContinuation
+
+                        if shouldPrompt {
+                            continuation.yield(.prompt(classified))
+                        }
+
+                        pendingLogs.append(line)
+
+                    case .stderr(_, let line):
+                        pendingLogs.append(line)
+
+                    case .jsonRow(_, let payload):
+                        do {
+                            let row = try JSONDecoder().decode(ChartreadRow.self, from: payload)
+                            state = row.isFinalRow ? .allStripsRead : state
+                            continuation.yield(.row(row))
+                        } catch {
+                            pendingLogs.append("Malformed row JSON: \(error.localizedDescription)")
+                        }
+
+                    case .error(_, let message):
+                        pendingLogs.append("Error: \(message)")
+
+                    case .exit(_, let code):
+                        exitCode = code
+                    }
+
+                    if exitCode == nil,
+                       pendingLogs.count >= 20 || Date().timeIntervalSince(lastFlush) >= 0.1 {
+                        flushLogs()
+                        lastFlush = Date()
+                    }
+
+                    if exitCode != nil {
+                        flushLogs()
+                        break
+                    }
+                }
+
+                if Task.isCancelled {
+                    continuation.finish()
+                    return
+                }
+
+                let canonical = cwd.appendingPathComponent("\(cleanBasename).ti3")
+                if let code = exitCode, code == 0 {
+                    if FileManager.default.fileExists(atPath: canonical.path) {
+                        continuation.yield(.completed(canonical))
+                    } else {
+                        continuation.yield(.failed(ArgyllRunnerError.missingArtefact(canonical.path)))
+                    }
+                } else {
+                    continuation.yield(.failed(ArgyllRunnerError.chartreadFailed("chartread exited with code \(exitCode ?? -1)")))
+                }
+                continuation.finish()
+            }
+
+            continuation.onTermination = { _ in
+                task.cancel()
+                Task {
+                    await processManager.kill(id: processId)
+                }
+            }
+        }
+    }
+
+    /// Send an exact input sequence to the running `chartread` child.
+    public func sendChartreadInput(basename: String, input: ChartreadInput) async throws {
+        let cleanBasename = try PathSecurity.sanitizeBasename(basename)
+        let processId = ProcessID.chartread(cleanBasename)
+        try await processManager.sendStdin(id: processId, bytes: input.bytes)
+    }
+
+    /// Terminate a running `chartread` child.
+    ///
+    /// The actual XY parking is handled by the pre-kill hook registered in
+    /// `runChartread`.
+    public func cancelChartread(basename: String, isXY: Bool = false) {
+        let cleanBasename = try? PathSecurity.sanitizeBasename(basename)
+        guard let cleanBasename else { return }
+        let processId = ProcessID.chartread(cleanBasename)
+
+        Task {
+            await processManager.kill(id: processId)
+        }
+    }
+}
+
+/// Events emitted by a running `chartread` session.
+public enum ChartreadEvent: Sendable {
+    /// Classified prompt / state update.
+    case prompt(ChartreadClassifyResult)
+    /// A decoded `ROW_COLORS_JSON` row.
+    case row(ChartreadRow)
+    /// A batched log chunk (stdout + stderr lines).
+    case log([String])
+    /// Informational "remove last sheet" notice.
+    case removeSheetNotice
+    /// Process exited with the given code.
+    case exit(Int32)
+    /// Successful completion with the canonical `.ti3` URL.
+    case completed(URL)
+    /// Failure (non-zero exit, missing artefact, spawn/parse error).
+    case failed(ArgyllRunnerError)
+}
+
+/// Exact bytes sent to `chartread` stdin.
+public enum ChartreadInput: Sendable {
+    case trigger    // " \n"
+    case accept     // "\n"
+    case done       // "d\n"
+    case quit       // "q\n"
+    case customKey(String)
+
+    public var bytes: Data {
+        switch self {
+        case .trigger:
+            return Data(" \n".utf8)
+        case .accept:
+            return Data("\n".utf8)
+        case .done:
+            return Data("d\n".utf8)
+        case .quit:
+            return Data("q\n".utf8)
+        case .customKey(let key):
+            return Data("\(key)\n".utf8)
+        }
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Argyll/BinaryResolver.swift

@@ -0,0 +1,100 @@
+import Foundation
+
+/// Resolves Argyll sidecar binaries (docs/04 §0.1 `resolve_binary`).
+///
+/// Order:
+/// 1. Settings `argyll_binary_dir` override — only if `<dir>/<name>`
+///    exists there.
+/// 2. Bundled `<bundle>/Resources/Argyll/<platform>/<name>`.
+///    On macOS, `macos-universal` wins whenever it contains the `instlist`
+///    marker; otherwise `macos-arm64` / `macos-x86_64` by host arch.
+/// 3. If nothing exists the *constructed* bundled path is still returned
+///    — a missing binary surfaces later as `process:error` on spawn,
+///    matching v1 semantics.
+public struct BinaryResolver: Sendable {
+
+    /// Root that contains the platform dirs — `Bundle.resource/Argyll` in
+    /// the app, a fixture dir in tests.
+    public let bundledRoot: URL
+    /// `settings.argyll_binary_dir`, already expanded to a URL.
+    public let overrideDir: URL?
+    /// Host architecture directory names, universal preferred.
+    public let archDirs: [String]
+
+    public init(
+        bundledRoot: URL = AppPaths.bundledArgyllDir,
+        overrideDir: URL? = nil,
+        archDirs: [String]? = nil
+    ) {
+        self.bundledRoot = bundledRoot
+        self.overrideDir = overrideDir
+        #if arch(arm64)
+        let fallback = ["macos-arm64", "macos-aarch64"]
+        #else
+        let fallback = ["macos-x86_64"]
+        #endif
+        self.archDirs = archDirs ?? ["macos-universal"] + fallback
+    }
+
+    /// Marker used to decide whether `macos-universal` is usable.
+    public static let markerBinary = "instlist"
+
+    /// Resolves a tool name to an absolute URL (never throws — see type
+    /// docs). `name` is the bare tool name, e.g. `"targen"`.
+    public func resolve(_ name: String) -> URL {
+        let fm = FileManager.default
+
+        if let dir = overrideDir {
+            let candidate = dir.appendingPathComponent(name)
+            if fm.fileExists(atPath: candidate.path) {
+                return candidate
+            }
+        }
+
+        return bundledRoot
+            .appendingPathComponent(platformDir(), isDirectory: true)
+            .appendingPathComponent(name, isDirectory: false)
+    }
+
+    /// The bundled platform directory that resolution will use.
+    public func platformDir() -> String {
+        let fm = FileManager.default
+        let universal = bundledRoot.appendingPathComponent("macos-universal")
+        if fm.fileExists(
+            atPath: universal.appendingPathComponent(Self.markerBinary).path
+        ) {
+            return "macos-universal"
+        }
+        for dir in archDirs where dir != "macos-universal" {
+            if fm.fileExists(
+                atPath: bundledRoot
+                    .appendingPathComponent(dir)
+                    .appendingPathComponent(Self.markerBinary).path
+            ) {
+                return dir
+            }
+        }
+        // Nothing present — still return the preferred dir so the error
+        // message points at where the user should drop binaries.
+        return archDirs.first ?? "macos-universal"
+    }
+
+    /// Bundled mock tool (tracked in git under `Resources/Argyll/mocks/`).
+    public func mock(_ name: String) -> URL {
+        bundledRoot
+            .appendingPathComponent("mocks", isDirectory: true)
+            .appendingPathComponent("\(name).mock", isDirectory: false)
+    }
+
+    /// Bundled reference gamut (`Resources/Argyll/reference_gamuts/`).
+    public func referenceGamut(_ name: String) -> URL {
+        bundledRoot
+            .appendingPathComponent("reference_gamuts", isDirectory: true)
+            .appendingPathComponent(name, isDirectory: false)
+    }
+
+    /// Whether the resolved path exists and is executable.
+    public func exists(_ url: URL) -> Bool {
+        FileManager.default.isExecutableFile(atPath: url.path)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Argyll/PrinttargArgs.swift

@@ -0,0 +1,99 @@
+import Foundation
+
+/// Errors during `buildPrinttargArgs` validation (docs/04 §2.2).
+public enum PrinttargArgError: LocalizedError, Equatable {
+    case invalidCustomPageDimension(Double)
+    case invalidDPI(Int)
+    case invalidSeed(Int)
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidCustomPageDimension(let mm):
+            return "Custom page dimensions must be at least 50 mm, got: \(mm)"
+        case .invalidDPI(let dpi):
+            return "TIFF DPI must be between 72 and 600, got: \(dpi)"
+        case .invalidSeed(let seed):
+            return "Custom layout seed must be ≥ 1, got: \(seed)"
+        }
+    }
+}
+
+/// Pure argv builder for Argyll's `printtarg` tool (docs/09, docs/04 §2.2).
+///
+/// Contract:
+/// ```
+/// -v -u -i {instrument} -p {page} [-r | -R seed] [-d label] {-t|-T} {dpi} [-K|-I cal] basename
+/// ```
+public enum PrinttargArgs {
+
+    /// Builds the exact command-line arguments for `printtarg`.
+    ///
+    /// Invariants:
+    /// - Always `-v -u` (the fork's `-u` emits the JSON page manifest).
+    /// - Default layout is deterministic `-R 1` (#163) — a missing seed
+    ///   reshuffles patches on every re-run and desyncs print vs `.ti2`.
+    /// - `.raster` emits `-r` and supersedes any seed. This is NOT
+    ///   targen's `-r` full-spread algorithm (docs/25).
+    /// - `-d` is the chart **label** string, not colour space.
+    /// - `-K`/`-I` are never emitted for `CAL_` basenames — the
+    ///   calibration chart must not embed its own curves.
+    /// - Basename is the last positional argument.
+    public static func build(config: PrinttargConfig) throws -> [String] {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+
+        var args: [String] = [
+            "-v", "-u",
+            "-i", config.instrument.rawValue,
+            "-p", try pageSizeValue(config),
+        ]
+
+        switch config.layoutOrder {
+        case .deterministic:
+            args.append(contentsOf: ["-R", "1"])
+        case .customSeed:
+            guard config.customSeed >= 1 else {
+                throw PrinttargArgError.invalidSeed(config.customSeed)
+            }
+            args.append(contentsOf: ["-R", "\(config.customSeed)"])
+        case .raster:
+            args.append("-r")
+        }
+
+        if let label = config.label?.trimmingCharacters(in: .whitespacesAndNewlines),
+           !label.isEmpty {
+            args.append(contentsOf: ["-d", label])
+        }
+
+        guard (72...600).contains(config.dpi) else {
+            throw PrinttargArgError.invalidDPI(config.dpi)
+        }
+        args.append(contentsOf: [config.bitDepth.flag, "\(config.dpi)"])
+
+        if !cleanBasename.hasPrefix("CAL_"),
+           let cal = config.calibrationFile?.trimmingCharacters(in: .whitespacesAndNewlines),
+           !cal.isEmpty {
+            args.append(contentsOf: [config.calibrationEmbedOnly ? "-I" : "-K", cal])
+        }
+
+        args.append(cleanBasename)
+        return args
+    }
+
+    private static func pageSizeValue(_ config: PrinttargConfig) throws -> String {
+        guard config.pageSize == .custom else { return config.pageSize.rawValue }
+        for dim in [config.customPageWidth, config.customPageHeight] {
+            guard dim >= 50 else {
+                throw PrinttargArgError.invalidCustomPageDimension(dim)
+            }
+        }
+        return "\(formatMM(config.customPageWidth))x\(formatMM(config.customPageHeight))"
+    }
+
+    /// Formats millimetres as an integer when exact, else decimal.
+    private static func formatMM(_ value: Double) -> String {
+        if value == value.rounded(), abs(value) < 1e15 {
+            return "\(Int(value))"
+        }
+        return String(format: "%.1f", locale: Locale(identifier: "en_US_POSIX"), value)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Argyll/PrinttargConfig.swift

@@ -0,0 +1,208 @@
+import Foundation
+
+/// Measurement instrument for `printtarg -i` chart geometry
+/// (docs/09, docs/04 §2.2). Raw values are the Argyll codes.
+public enum PrintInstrument: String, Codable, Sendable, CaseIterable {
+    case i1
+    case p3
+    case cm = "CM"
+    case ss = "SS"
+    case dtp20 = "20"
+    case dtp22 = "22"
+    case dtp41 = "41"
+    case dtp51 = "51"
+
+    public var displayName: String {
+        switch self {
+        case .i1:    return "X-Rite i1Pro / i1Pro 2"
+        case .p3:    return "X-Rite i1Pro 3 / 3 Plus"
+        case .cm:    return "ColorMunki"
+        case .ss:    return "Specbos / Spectraval (XY table)"
+        case .dtp20: return "Gretag i1Display 2"
+        case .dtp22: return "X-Rite i1Display Pro / ColorMunki Display"
+        case .dtp41: return "Datacolor Spyder 4/5"
+        case .dtp51: return "Spyder X"
+        }
+    }
+}
+
+/// Page size for `printtarg -p` (docs/09). `.custom` emits `{W}x{H}` mm.
+public enum PageSize: String, Codable, Sendable, CaseIterable {
+    case a4 = "A4"
+    case a4r = "A4R"
+    case a3 = "A3"
+    case a2 = "A2"
+    case letter = "Letter"
+    case letterR = "LetterR"
+    case legal = "Legal"
+    case fourBySix = "4x6"
+    case elevenBySeventeen = "11x17"
+    case custom = "custom"
+
+    public var isCustom: Bool { self == .custom }
+}
+
+/// TIFF bit depth: `-t` (8-bit) or `-T` (16-bit).
+public enum TiffBitDepth: Int, Codable, Sendable, CaseIterable {
+    case eight = 8
+    case sixteen = 16
+
+    public var flag: String {
+        switch self {
+        case .eight:   return "-t"
+        case .sixteen: return "-T"
+        }
+    }
+}
+
+/// Patch layout order (docs/09 §Randomisation, #163).
+/// `.deterministic` is the default (`-R 1`); `.raster` emits `-r` and
+/// supersedes any seed — never confuse with targen's `-r` algorithm.
+public enum LayoutOrder: String, Codable, Sendable, CaseIterable {
+    case deterministic
+    case customSeed = "custom_seed"
+    case raster
+
+    public var displayName: String {
+        switch self {
+        case .deterministic: return "Deterministic (seed 1)"
+        case .customSeed:    return "Custom seed"
+        case .raster:        return "Raster order (no shuffle)"
+        }
+    }
+}
+
+/// Chart label metadata used to assemble the automatic `printtarg -d`
+/// label. Any empty/missing component becomes `Unspecified` until real
+/// printer metadata lands in M3.
+public struct TargetLabelMetadata: Codable, Equatable, Sendable {
+    public var printer: String
+    public var inkSet: String
+    public var driverPaper: String
+    public var actualPaper: String
+
+    public init(
+        printer: String = "",
+        inkSet: String = "",
+        driverPaper: String = "",
+        actualPaper: String = ""
+    ) {
+        self.printer = printer
+        self.inkSet = inkSet
+        self.driverPaper = driverPaper
+        self.actualPaper = actualPaper
+    }
+}
+
+/// Builds the chart legend for `printtarg -d` (fork argyllcms#19,
+/// ICCery #119). `-d` here is a **label string** — not targen's colour
+/// space, not iccgamut's density (docs/25).
+public enum PrinttargLabel {
+
+    public static let unspecified = "Unspecified"
+
+    /// `ICCery - {basename} - {printer} - {ink} - {driverPaper} -
+    /// {actualPaper} - DD/MM/YYYY HH:MM`
+    ///
+    /// `date` is injected for deterministic tests; production passes
+    /// the current local time. A fixed POSIX locale keeps the format
+    /// stable regardless of user locale.
+    public static func automatic(
+        basename: String,
+        metadata: TargetLabelMetadata,
+        date: Date = Date(),
+        timeZone: TimeZone = .current
+    ) -> String {
+        let formatter = DateFormatter()
+        formatter.locale = Locale(identifier: "en_US_POSIX")
+        formatter.timeZone = timeZone
+        formatter.dateFormat = "dd/MM/yyyy HH:mm"
+
+        return [
+            "ICCery",
+            basename,
+            field(metadata.printer),
+            field(metadata.inkSet),
+            field(metadata.driverPaper),
+            field(metadata.actualPaper),
+            formatter.string(from: date),
+        ].joined(separator: " - ")
+    }
+
+    /// Resolves the label to emit: an explicit non-empty manual label
+    /// wins; otherwise the assembled automatic label.
+    public static func resolved(
+        customLabel: String?,
+        basename: String,
+        metadata: TargetLabelMetadata,
+        date: Date = Date(),
+        timeZone: TimeZone = .current
+    ) -> String {
+        if let label = customLabel?.trimmingCharacters(in: .whitespacesAndNewlines),
+           !label.isEmpty {
+            return label
+        }
+        return automatic(basename: basename, metadata: metadata, date: date, timeZone: timeZone)
+    }
+
+    private static func field(_ value: String) -> String {
+        let trimmed = value.trimmingCharacters(in: .whitespacesAndNewlines)
+        return trimmed.isEmpty ? unspecified : trimmed
+    }
+}
+
+/// Configuration model for `printtarg` invocation (docs/09, docs/04 §2.2).
+public struct PrinttargConfig: Codable, Equatable, Sendable {
+    public var instrument: PrintInstrument
+    public var pageSize: PageSize
+    /// Custom page dimensions in millimetres; each must be ≥ 50 when
+    /// `pageSize == .custom`.
+    public var customPageWidth: Double
+    public var customPageHeight: Double
+    public var bitDepth: TiffBitDepth
+    public var dpi: Int
+    public var layoutOrder: LayoutOrder
+    /// Seed for `.customSeed` layout (`-R N`, N ≥ 1). Ignored for
+    /// `.deterministic` (fixed `-R 1`) and `.raster` (`-r`).
+    public var customSeed: Int
+    /// Resolved `-d` label. Callers usually compute this via
+    /// `PrinttargLabel.resolved` so tests can inject the clock.
+    public var label: String?
+    /// `.cal` file applied to printed patches (`-K`), or embedded
+    /// without applying (`-I` when `calibrationEmbedOnly`). Never
+    /// emitted for `CAL_` basenames (Stage 0 protection).
+    public var calibrationFile: String?
+    public var calibrationEmbedOnly: Bool
+    public var basename: String
+    public var workingDirectory: URL?
+
+    public init(
+        instrument: PrintInstrument = .i1,
+        pageSize: PageSize = .a4,
+        customPageWidth: Double = 210,
+        customPageHeight: Double = 297,
+        bitDepth: TiffBitDepth = .eight,
+        dpi: Int = 300,
+        layoutOrder: LayoutOrder = .deterministic,
+        customSeed: Int = 1,
+        label: String? = nil,
+        calibrationFile: String? = nil,
+        calibrationEmbedOnly: Bool = false,
+        basename: String = "",
+        workingDirectory: URL? = nil
+    ) {
+        self.instrument = instrument
+        self.pageSize = pageSize
+        self.customPageWidth = customPageWidth
+        self.customPageHeight = customPageHeight
+        self.bitDepth = bitDepth
+        self.dpi = dpi
+        self.layoutOrder = layoutOrder
+        self.customSeed = customSeed
+        self.label = label
+        self.calibrationFile = calibrationFile
+        self.calibrationEmbedOnly = calibrationEmbedOnly
+        self.basename = basename
+        self.workingDirectory = workingDirectory
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Argyll/PrinttargManifest.swift

@@ -0,0 +1,180 @@
+import Foundation
+
+/// One page of a `printtarg -u` manifest (docs/05 §2.3).
+/// `patches` is a page-assigned count including TID/padding cells,
+/// not strictly user patches.
+public struct PrinttargPage: Codable, Equatable, Sendable {
+    public var filename: String
+    public var patches: Int
+    public var widthMm: Double
+    public var heightMm: Double
+
+    public init(filename: String, patches: Int, widthMm: Double, heightMm: Double) {
+        self.filename = filename
+        self.patches = patches
+        self.widthMm = widthMm
+        self.heightMm = heightMm
+    }
+
+    enum CodingKeys: String, CodingKey {
+        case filename, patches
+        case widthMm = "width_mm"
+        case heightMm = "height_mm"
+    }
+}
+
+/// The final-only, pretty-printed, **unprefixed** JSON object emitted
+/// by fork `printtarg -u` after all pages are written (docs/05 §2.3).
+public struct PrinttargManifest: Codable, Equatable, Sendable {
+    public var event: String
+    public var pages: [PrinttargPage]
+
+    public init(event: String = "manifest", pages: [PrinttargPage]) {
+        self.event = event
+        self.pages = pages
+    }
+}
+
+/// A manifest page resolved against the working directory, with its
+/// host-side PNG preview (#58 — TIFF is never fed to the UI directly).
+public struct GalleryPage: Equatable, Sendable, Identifiable {
+    public var id: Int { index }
+    public let index: Int
+    public let page: PrinttargPage
+    public let fileURL: URL
+    public let previewPNG: Data?
+    public let previewError: String?
+
+    public init(index: Int, page: PrinttargPage, fileURL: URL, previewPNG: Data?, previewError: String?) {
+        self.index = index
+        self.page = page
+        self.fileURL = fileURL
+        self.previewPNG = previewPNG
+        self.previewError = previewError
+    }
+}
+
+public enum ManifestError: LocalizedError, Equatable {
+    case noJSONDocument
+    case wrongEvent(String)
+    case decodeFailed(String)
+    case invalidPage(String)
+
+    public var errorDescription: String? {
+        switch self {
+        case .noJSONDocument:
+            return "No JSON document found in printtarg stdout."
+        case .wrongEvent(let event):
+            return "Unexpected JSON event \"\(event)\" — expected \"manifest\"."
+        case .decodeFailed(let reason):
+            return "printtarg manifest JSON failed to decode: \(reason)"
+        case .invalidPage(let reason):
+            return "printtarg manifest page is invalid: \(reason)"
+        }
+    }
+}
+
+/// Extracts and decodes the `printtarg -u` manifest from the complete
+/// accumulated stdout (docs/04 §2.3, docs/09 §JSON manifest).
+///
+/// #68 invariant: the JSON is a structured document, not a brace-hunt.
+/// Extraction is string/escape-aware — a `{` or `}` inside a quoted
+/// filename can never corrupt the scan — and starts only at a `{` that
+/// begins a trimmed stdout line.
+public enum PrinttargManifestExtractor {
+
+    /// Finds the manifest object in accumulated stdout.
+    public static func manifest(from stdout: String) throws -> PrinttargManifest {
+        for block in jsonObjects(in: stdout) {
+            let data = Data(block.utf8)
+            guard let manifest = try? JSONDecoder().decode(PrinttargManifest.self, from: data) else {
+                continue
+            }
+            guard manifest.event == "manifest" else {
+                throw ManifestError.wrongEvent(manifest.event)
+            }
+            try validate(manifest)
+            return manifest
+        }
+        if let first = jsonObjects(in: stdout).first,
+           let obj = try? JSONSerialization.jsonObject(with: Data(first.utf8)) as? [String: Any],
+           let event = obj["event"] as? String {
+            throw ManifestError.wrongEvent(event)
+        }
+        throw ManifestError.noJSONDocument
+    }
+
+    private static func validate(_ manifest: PrinttargManifest) throws {
+        for page in manifest.pages {
+            guard page.patches >= 0 else {
+                throw ManifestError.invalidPage("negative patch count \(page.patches)")
+            }
+            guard page.widthMm > 0, page.heightMm > 0 else {
+                throw ManifestError.invalidPage("non-positive page size \(page.widthMm)x\(page.heightMm)")
+            }
+            let name = page.filename
+            guard !name.isEmpty,
+                  !name.hasPrefix("/"),
+                  !name.contains("/"),
+                  !name.contains("\\"),
+                  !name.contains("..") else {
+                throw ManifestError.invalidPage("unsafe filename \"\(name)\"")
+            }
+            let ext = (name as NSString).pathExtension.lowercased()
+            guard ext == "tif" || ext == "tiff" else {
+                throw ManifestError.invalidPage("non-TIFF filename \"\(name)\"")
+            }
+        }
+    }
+
+    /// Yields every complete top-level JSON object `{...}` found at a
+    /// trimmed line boundary, in document order. Depth tracking respects
+    /// quoted strings and backslash escapes.
+    static func jsonObjects(in text: String) -> [String] {
+        var out: [String] = []
+        let scalars = Array(text.unicodeScalars)
+        var i = 0
+
+        func isLineStart(_ idx: Int) -> Bool {
+            var j = idx - 1
+            while j >= 0 && scalars[j] != "\n" {
+                if scalars[j] != " " && scalars[j] != "\t" && scalars[j] != "\r" {
+                    return false
+                }
+                j -= 1
+            }
+            return true
+        }
+
+        while i < scalars.count {
+            if scalars[i] == "{", isLineStart(i) {
+                var depth = 0
+                var inString = false
+                var escaped = false
+                var j = i
+                while j < scalars.count {
+                    let c = scalars[j]
+                    if inString {
+                        if escaped { escaped = false }
+                        else if c == "\\" { escaped = true }
+                        else if c == "\"" { inString = false }
+                    } else {
+                        if c == "\"" { inString = true }
+                        else if c == "{" { depth += 1 }
+                        else if c == "}" {
+                            depth -= 1
+                            if depth == 0 {
+                                out.append(String(String.UnicodeScalarView(scalars[i...j])))
+                                i = j
+                                break
+                            }
+                        }
+                    }
+                    j += 1
+                }
+            }
+            i += 1
+        }
+        return out
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Argyll/TargenArgs.swift

@@ -0,0 +1,104 @@
+import Foundation
+
+/// Errors during `buildTargenArgs` validation (docs/04 §1.2).
+public enum TargenArgError: LocalizedError, Equatable {
+    case invalidBasename(String)
+    case invalidPatchCount(Int)
+    case invalidWhitePatches(Int)
+    case invalidBlackPatches(Int)
+    case invalidInkLimit(Int)
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidBasename(let name):
+            return "Invalid target basename: \(name)"
+        case .invalidPatchCount(let count):
+            return "Patch count must be positive, got: \(count)"
+        case .invalidWhitePatches(let count):
+            return "White patches cannot be negative, got: \(count)"
+        case .invalidBlackPatches(let count):
+            return "Black patches cannot be negative, got: \(count)"
+        case .invalidInkLimit(let limit):
+            return "Ink limit must be between 1 and 400, got: \(limit)"
+        }
+    }
+}
+
+/// Pure argv builder for Argyll's `targen` tool (docs/08, docs/04 §1.2).
+public enum TargenArgs {
+
+    /// Builds the exact command-line arguments for `targen`.
+    ///
+    /// Invariants:
+    /// - Always starts `-v -d {2|4}` (RGB=2, CMYK=4).
+    /// - Never emits `-u` (Argyll fork progress is not enabled for targen).
+    /// - Always emits `-f N` when patchCount > 0 (#44).
+    /// - White `-e`, Black `-B`.
+    /// - `-N` omitted when approximately 0.50.
+    /// - `-A` is emitted even at 0.10 (no default-skip).
+    /// - `-l` is CMYK only (1...400).
+    /// - `-V` omitted when approximately 1.0.
+    /// - `-p` omitted when non-positive or approximately 1.0.
+    /// - Basename is the last positional argument.
+    public static func build(config: TargenConfig) throws -> [String] {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+
+        guard config.patchCount > 0 else {
+            throw TargenArgError.invalidPatchCount(config.patchCount)
+        }
+        guard config.whitePatches >= 0 else {
+            throw TargenArgError.invalidWhitePatches(config.whitePatches)
+        }
+        guard config.blackPatches >= 0 else {
+            throw TargenArgError.invalidBlackPatches(config.blackPatches)
+        }
+
+        var args: [String] = [
+            "-v",
+            "-d", config.colourSpace.dFlagValue,
+            "-f", "\(config.patchCount)",
+            "-e", "\(config.whitePatches)",
+            "-B", "\(config.blackPatches)"
+        ]
+
+        if let g = config.greySteps, g > 0 {
+            args.append(contentsOf: ["-g", "\(g)"])
+        }
+        if let s = config.singleChannelSteps, s > 0 {
+            args.append(contentsOf: ["-s", "\(s)"])
+        }
+        if let n = config.neutralSteps, n > 0 {
+            args.append(contentsOf: ["-n", "\(n)"])
+        }
+        if let nConc = config.neutralConcentration, abs(nConc - 0.50) >= 0.001 {
+            args.append(contentsOf: ["-N", String(format: "%.2f", locale: Locale(identifier: "en_US_POSIX"), nConc)])
+        }
+        if let c = config.preconditioningProfile?.trimmingCharacters(in: .whitespacesAndNewlines), !c.isEmpty {
+            args.append(contentsOf: ["-c", c])
+        }
+        if config.ofpsHighQuality == true {
+            args.append("-G")
+        }
+        if let a = config.ofpsAdaptation {
+            args.append(contentsOf: ["-A", String(format: "%.2f", locale: Locale(identifier: "en_US_POSIX"), a)])
+        }
+        if let algFlag = config.fullSpreadAlgorithm?.flag {
+            args.append(algFlag)
+        }
+        if config.colourSpace == .cmyk, let inkLimit = config.totalInkLimit {
+            guard (1...400).contains(inkLimit) else {
+                throw TargenArgError.invalidInkLimit(inkLimit)
+            }
+            args.append(contentsOf: ["-l", "\(inkLimit)"])
+        }
+        if let v = config.darkEmphasis, abs(v - 1.0) >= 0.001 {
+            args.append(contentsOf: ["-V", String(format: "%.2f", locale: Locale(identifier: "en_US_POSIX"), v)])
+        }
+        if let p = config.devicePower, p > 0, abs(p - 1.0) >= 0.001 {
+            args.append(contentsOf: ["-p", String(format: "%.2f", locale: Locale(identifier: "en_US_POSIX"), p)])
+        }
+
+        args.append(cleanBasename)
+        return args
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Argyll/TargenConfig.swift

@@ -0,0 +1,150 @@
+import Foundation
+
+/// Colour space for patch generation (docs/08, docs/04 §1.2).
+public enum ColourSpace: String, Codable, Sendable, CaseIterable {
+    case rgb
+    case cmyk
+
+    /// Argyll targen `-d` flag argument: 2 for RGB, 4 for CMYK.
+    public var dFlagValue: String {
+        switch self {
+        case .rgb: return "2"
+        case .cmyk: return "4"
+        }
+    }
+}
+
+/// Patch count preset for Stage 1.
+public enum PatchCountPreset: String, Codable, Sendable, CaseIterable {
+    case draft400 = "400"
+    case standard800 = "800"
+    case photo1500 = "1500"
+    case custom = "custom"
+
+    public var patchCount: Int? {
+        switch self {
+        case .draft400: return 400
+        case .standard800: return 800
+        case .photo1500: return 1500
+        case .custom: return nil
+        }
+    }
+
+    public var title: String {
+        switch self {
+        case .draft400: return "Draft (400)"
+        case .standard800: return "Standard (800)"
+        case .photo1500: return "Photo (1500)"
+        case .custom: return "Custom"
+        }
+    }
+}
+
+/// Full spread patch distribution algorithm (docs/08).
+/// Default is "ofps" (no flag emitted).
+public enum FullSpreadAlgorithm: String, Codable, Sendable, CaseIterable {
+    case ofps = "ofps"
+    case target = "-t"
+    case random = "-r"
+    case uniformRandom = "-R"
+    case quasiRandom = "-q"
+    case uniformQuasiRandom = "-Q"
+    case invertedQuasiRandom = "-i"
+    case invertedUniformQuasiRandom = "-I"
+
+    public var displayName: String {
+        switch self {
+        case .ofps: return "OFPS (Default)"
+        case .target: return "Target (-t)"
+        case .random: return "Random (-r)"
+        case .uniformRandom: return "Uniform Random (-R)"
+        case .quasiRandom: return "Quasi-random (-q)"
+        case .uniformQuasiRandom: return "Uniform Quasi-random (-Q)"
+        case .invertedQuasiRandom: return "Inverted Quasi-random (-i)"
+        case .invertedUniformQuasiRandom: return "Inverted Uniform Quasi-random (-I)"
+        }
+    }
+
+    public var flag: String? {
+        switch self {
+        case .ofps: return nil
+        default: return rawValue
+        }
+    }
+
+    /// Preset JSON value: `"ofps"` or the bare flag letter
+    /// (`t`, `r`, `R`, `q`, `Q`, `i`, `I`) — docs/22.
+    public var presetValue: String {
+        switch self {
+        case .ofps: return "ofps"
+        default: return String(rawValue.dropFirst())
+        }
+    }
+
+    public init?(presetValue: String) {
+        if presetValue == "ofps" {
+            self = .ofps
+        } else {
+            self.init(rawValue: "-" + presetValue)
+        }
+    }
+}
+
+/// Configuration model for `targen` invocation (docs/08, docs/04 §1.2).
+public struct TargenConfig: Codable, Equatable, Sendable {
+    public var colourSpace: ColourSpace
+    public var patchCount: Int
+    public var whitePatches: Int
+    public var blackPatches: Int
+    public var greySteps: Int?
+    public var singleChannelSteps: Int?
+    public var neutralSteps: Int?
+    public var neutralConcentration: Double?
+    public var preconditioningProfile: String?
+    public var ofpsHighQuality: Bool?
+    public var ofpsAdaptation: Double?
+    public var fullSpreadAlgorithm: FullSpreadAlgorithm?
+    public var totalInkLimit: Int?
+    public var darkEmphasis: Double?
+    public var devicePower: Double?
+    public var basename: String
+    public var workingDirectory: URL?
+
+    public init(
+        colourSpace: ColourSpace = .rgb,
+        patchCount: Int = 800,
+        whitePatches: Int = 4,
+        blackPatches: Int = 4,
+        greySteps: Int? = nil,
+        singleChannelSteps: Int? = nil,
+        neutralSteps: Int? = nil,
+        neutralConcentration: Double? = nil,
+        preconditioningProfile: String? = nil,
+        ofpsHighQuality: Bool? = nil,
+        ofpsAdaptation: Double? = nil,
+        fullSpreadAlgorithm: FullSpreadAlgorithm? = nil,
+        totalInkLimit: Int? = nil,
+        darkEmphasis: Double? = nil,
+        devicePower: Double? = nil,
+        basename: String = "",
+        workingDirectory: URL? = nil
+    ) {
+        self.colourSpace = colourSpace
+        self.patchCount = patchCount
+        self.whitePatches = whitePatches
+        self.blackPatches = blackPatches
+        self.greySteps = greySteps
+        self.singleChannelSteps = singleChannelSteps
+        self.neutralSteps = neutralSteps
+        self.neutralConcentration = neutralConcentration
+        self.preconditioningProfile = preconditioningProfile
+        self.ofpsHighQuality = ofpsHighQuality
+        self.ofpsAdaptation = ofpsAdaptation
+        self.fullSpreadAlgorithm = fullSpreadAlgorithm
+        self.totalInkLimit = totalInkLimit
+        self.darkEmphasis = darkEmphasis
+        self.devicePower = devicePower
+        self.basename = basename
+        self.workingDirectory = workingDirectory
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/CGATS/CGATSParser.swift

@@ -0,0 +1,372 @@
+import Foundation
+
+/// Errors that can occur while parsing CGATS-like data.
+public enum CGATSParseError: Error, Equatable {
+    case emptyFile
+    case missingBeginDataFormat
+    case missingEndDataFormat
+    case missingBeginData
+    case missingEndData
+    case missingNumberOfFields
+    case missingNumberOfSets
+    case unknownFieldName(String)
+    case malformedRow(line: Int, reason: String)
+    case nonNumericValue(field: String, value: String, line: Int)
+    case outOfBoundsValue(field: String, value: Double, line: Int)
+    case implausibleValue(field: String, value: Double, line: Int)
+    case incorrectArity(line: Int, expected: Int, got: Int)
+}
+
+/// One row of a CGATS dataset, keyed by canonical field name.
+public struct CGATSSample: Sendable, Equatable {
+    public var id: String
+    public var loc: String?
+    public var values: [String: String]
+
+    public init(id: String, loc: String? = nil, values: [String: String] = [:]) {
+        self.id = id
+        self.loc = loc
+        self.values = values
+    }
+}
+
+/// A parsed CGATS / CTI3 / CSV dataset.
+public struct CGATSDataset: Sendable, Equatable {
+    public var format: CGATSFormat
+    public var keywords: [String: String]
+    public var fieldNames: [String]
+    public var samples: [CGATSSample]
+    public var colorRep: String?
+    public var deviceClass: String?
+    public var targetInstrument: String?
+
+    public init(
+        format: CGATSFormat,
+        keywords: [String: String] = [:],
+        fieldNames: [String] = [],
+        samples: [CGATSSample] = [],
+        colorRep: String? = nil,
+        deviceClass: String? = nil,
+        targetInstrument: String? = nil
+    ) {
+        self.format = format
+        self.keywords = keywords
+        self.fieldNames = fieldNames
+        self.samples = samples
+        self.colorRep = colorRep
+        self.deviceClass = deviceClass
+        self.targetInstrument = targetInstrument
+    }
+}
+
+public enum CGATSFormat: String, Sendable, Equatable {
+    case cti3 = "CTI3"
+    case cgats17 = "CGATS.17"
+    case csv = "CSV"
+}
+
+/// Parser for CGATS.17, CTI3, ISO28178, and simple CSV datasets.
+public enum CGATSParser {
+
+    /// Parse the contents of a CGATS-like file.
+    public static func parse(
+        _ contents: String,
+        sourceURL: URL? = nil
+    ) throws(CGATSParseError) -> CGATSDataset {
+        guard !contents.isEmpty else { throw .emptyFile }
+
+        let ext = sourceURL?.pathExtension.lowercased() ?? ""
+        let isCSV = ext == "csv" || contents.trimmingCharacters(in: .whitespacesAndNewlines)
+            .hasPrefix("SAMPLE_ID,")
+
+        let (format, lines) = try preprocess(contents, isCSV: isCSV)
+
+        var formatStart: Int?
+        var formatEnd: Int?
+        var dataStart: Int?
+        var dataEnd: Int?
+        var keywords = [String: String]()
+
+        for (index, line) in lines.enumerated() {
+            switch Self.normalizedKeyword(line) {
+            case "BEGIN_DATA_FORMAT": formatStart = index
+            case "END_DATA_FORMAT":   formatEnd = index
+            case "BEGIN_DATA":        dataStart = index
+            case "END_DATA":          dataEnd = index
+            default:
+                if let (key, value) = parseKeyword(line) {
+                    keywords[key] = value
+                }
+            }
+        }
+
+        guard let formatStart, let formatEnd, formatEnd > formatStart + 1 else {
+            throw .missingBeginDataFormat
+        }
+        guard let dataStart, let dataEnd, dataEnd > dataStart + 1 else {
+            throw .missingBeginData
+        }
+
+        let rawFieldNames = splitFields(lines[formatStart + 1])
+        let fieldNames = rawFieldNames.map { canonicalFieldName($0) }
+
+        if let numberOfFields = keywords["NUMBER_OF_FIELDS"].flatMap(Int.init),
+           numberOfFields != fieldNames.count {
+            // Warn only; the data format line is the source of truth.
+        } else if keywords["NUMBER_OF_FIELDS"] == nil {
+            // Optional header; do not fail.
+        }
+
+        if let numberOfSets = keywords["NUMBER_OF_SETS"].flatMap(Int.init),
+           numberOfSets != dataEnd - dataStart - 1 {
+            // Warn only; the actual rows are the source of truth.
+        } else if keywords["NUMBER_OF_SETS"] == nil {
+            // Optional header; do not fail.
+        }
+
+        struct RawSample {
+            var id: String
+            var loc: String?
+            var numbers: [String: Double] = [:]
+            var strings: [String: String] = [:]
+            var lineIndex: Int
+        }
+
+        var rawSamples = [RawSample]()
+        var groupMax: [String: Double] = [:]
+
+        for offset in 1...(dataEnd - dataStart - 1) {
+            let lineIndex = dataStart + offset
+            let rawRow = splitFields(lines[lineIndex])
+            guard rawRow.count == fieldNames.count else {
+                throw .incorrectArity(line: lineIndex + 1, expected: fieldNames.count, got: rawRow.count)
+            }
+
+            var sample = RawSample(id: String(offset), lineIndex: lineIndex)
+            for (i, name) in fieldNames.enumerated() {
+                let raw = stripInlineComment(rawRow[i])
+                if isNumericField(name) {
+                    let cleaned = raw.trimmingCharacters(in: .whitespaces)
+                    if let number = parseNumber(cleaned) {
+                        sample.numbers[name] = number
+                        if let group = deviceGroup(name) {
+                            groupMax[group, default: 0] = max(groupMax[group, default: 0], number)
+                        }
+                    } else if !cleaned.isEmpty {
+                        throw .nonNumericValue(field: name, value: raw, line: lineIndex + 1)
+                    }
+                } else {
+                    sample.strings[name] = raw
+                }
+            }
+
+            sample.id = sample.strings["SAMPLE_ID"] ?? sample.numbers["SAMPLE_ID"].map { String(format: "%.0f", $0) } ?? String(offset)
+            sample.loc = sample.strings["SAMPLE_LOC"]
+            rawSamples.append(sample)
+        }
+
+        var samples = [CGATSSample]()
+        for raw in rawSamples {
+            var values = raw.strings
+            for (name, number) in raw.numbers {
+                var scaled = number
+                if let group = deviceGroup(name), let maxValue = groupMax[group], maxValue > 100 {
+                    scaled = number / 2.55
+                }
+                values[name] = validateValue(scaled, field: name, line: raw.lineIndex + 1)
+            }
+
+            var sample = CGATSSample(id: raw.id, loc: raw.loc, values: values)
+            // Keep lookups by canonical keys, but also preserve original aliases.
+            let rawRow = splitFields(lines[raw.lineIndex])
+            for (i, rawName) in rawFieldNames.enumerated() {
+                let canonical = canonicalFieldName(rawName)
+                if canonical != rawName {
+                    sample.values[rawName] = rawRow[i]
+                }
+            }
+            samples.append(sample)
+        }
+
+        let colorRep = keywords["COLOR_REP"] ?? inferColorRep(fieldNames: fieldNames)
+        let deviceClass = keywords["DEVICE_CLASS"] ?? inferDeviceClass(fieldNames: fieldNames)
+
+        return CGATSDataset(
+            format: format,
+            keywords: keywords,
+            fieldNames: fieldNames,
+            samples: samples,
+            colorRep: colorRep,
+            deviceClass: deviceClass,
+            targetInstrument: keywords["TARGET_INSTRUMENT"]
+        )
+    }
+
+    /// Parse from a URL (throws as `Error` for public callers).
+    public static func parse(url: URL) throws -> CGATSDataset {
+        let contents = try String(contentsOf: url)
+        return try parse(contents, sourceURL: url)
+    }
+
+    // MARK: - Internals
+
+    private static func preprocess(
+        _ contents: String,
+        isCSV: Bool
+    ) throws(CGATSParseError) -> (CGATSFormat, [String]) {
+        let allLines = contents.components(separatedBy: .newlines)
+        var lines = [String]()
+
+        var format: CGATSFormat?
+        for var line in allLines {
+            line = stripComment(line)
+            line = line.trimmingCharacters(in: .whitespaces)
+            guard !line.isEmpty else { continue }
+
+            if format == nil {
+                if line.hasPrefix("CTI3") { format = .cti3 }
+                else if line.hasPrefix("CGATS.17") { format = .cgats17 }
+                else if isCSV { format = .csv }
+            }
+
+            if line == "BEGIN_DATA_FORMAT" || line == "END_DATA_FORMAT" ||
+               line == "BEGIN_DATA" || line == "END_DATA" ||
+               (line.hasPrefix("BEGIN_DATA_FORMAT") || line.hasPrefix("END_DATA_FORMAT") ||
+                line.hasPrefix("BEGIN_DATA") || line.hasPrefix("END_DATA")) {
+                // These are exact keywords; keep them intact.
+            }
+
+            lines.append(line)
+        }
+
+        guard !lines.isEmpty else { throw .emptyFile }
+
+        // Wrap a bare CSV / ISO28178 file in the canonical CGATS block
+        // structure so the boundary-based parser below can handle it.
+        if let format, format == .csv,
+           !lines.contains(where: { Self.normalizedKeyword($0) == "BEGIN_DATA_FORMAT" }) {
+            let header = lines[0]
+            let data = lines.dropFirst()
+            lines = [
+                "CTI3",
+                "BEGIN_DATA_FORMAT",
+                header,
+                "END_DATA_FORMAT",
+                "BEGIN_DATA"
+            ] + Array(data) + [
+                "END_DATA"
+            ]
+            return (.csv, lines)
+        }
+
+        return (format ?? .cti3, lines)
+    }
+
+    private static func stripComment(_ line: String) -> String {
+        if let range = line.range(of: "#") {
+            return String(line[..<range.lowerBound])
+        }
+        return line
+    }
+
+    private static func stripInlineComment(_ token: String) -> String {
+        if let range = token.range(of: "#") {
+            return String(token[..<range.lowerBound]).trimmingCharacters(in: .whitespaces)
+        }
+        return token
+    }
+
+    private static func splitFields(_ line: String) -> [String] {
+        // CTI3/CGATS.17 use whitespace/tabs; CSV uses commas.
+        if line.contains(",") {
+            return line.components(separatedBy: ",").map { $0.trimmingCharacters(in: .whitespaces) }
+        }
+        return line.components(separatedBy: .whitespaces).filter { !$0.isEmpty }
+    }
+
+    private static func parseKeyword(_ line: String) -> (key: String, value: String)? {
+        // KEYWORD value  or  KEYWORD "value"
+        let tokens = splitFields(line)
+        guard let key = tokens.first else { return nil }
+
+        // Data-boundary keywords are not value keywords.
+        let boundaryKeys = Set([
+            "BEGIN_DATA_FORMAT", "END_DATA_FORMAT",
+            "BEGIN_DATA", "END_DATA"
+        ])
+        guard !boundaryKeys.contains(key) else { return nil }
+
+        let rawValue = tokens.dropFirst().joined(separator: " ")
+        let value = rawValue.trimmingCharacters(in: CharacterSet(charactersIn: "\""))
+        return (key, value)
+    }
+
+    private static func normalizedKeyword(_ line: String) -> String {
+        line.uppercased().trimmingCharacters(in: .whitespaces)
+    }
+
+    // MARK: - Field name normalization
+
+    private static func canonicalFieldName(_ raw: String) -> String {
+        let upper = raw.uppercased()
+            .replacingOccurrences(of: " ", with: "_")
+            .replacingOccurrences(of: "-", with: "_")
+        switch upper {
+        case "SAMPLE_ID", "ID": return "SAMPLE_ID"
+        case "SAMPLE_LOC", "LOC": return "SAMPLE_LOC"
+        case "SAMPLE_NAME": return "SAMPLE_ID"
+        case "LAB_L", "L*", "L_AB": return "LAB_L"
+        case "LAB_A", "A*", "A_AB": return "LAB_A"
+        case "LAB_B", "B*", "B_AB": return "LAB_B"
+        case "XYZ_X", "X": return "XYZ_X"
+        case "XYZ_Y", "Y": return "XYZ_Y"
+        case "XYZ_Z", "Z": return "XYZ_Z"
+        default: return upper
+        }
+    }
+
+    private static func isNumericField(_ name: String) -> Bool {
+        let numericNames: Set = [
+            "SAMPLE_ID", "SAMPLE_LOC", "SAMPLE_NAME"
+        ]
+        return !numericNames.contains(name)
+    }
+
+    private static func parseNumber(_ raw: String) -> Double? {
+        let formatter = NumberFormatter()
+        formatter.numberStyle = .decimal
+        return formatter.number(from: raw)?.doubleValue
+    }
+
+    private static func validateValue(_ value: Double, field: String, line: Int) -> String {
+        var number = value
+
+        // Plausibility checks for Lab and XYZ.
+        if field == "LAB_L" { number = max(0, min(160, number)) }
+        if field == "LAB_A" || field == "LAB_B" { number = max(-128, min(128, number)) }
+        if field.hasPrefix("XYZ_") { number = max(0, min(200, number)) }
+
+        return String(format: "%.4f", number)
+    }
+
+    private static func deviceGroup(_ name: String) -> String? {
+        if name.hasPrefix("RGB_") { return "RGB" }
+        if name.hasPrefix("CMYK_") { return "CMYK" }
+        if name.hasPrefix("DEVICE_") { return "DEVICE" }
+        return nil
+    }
+
+    private static func inferColorRep(fieldNames: [String]) -> String? {
+        if fieldNames.contains(where: { $0.hasPrefix("CMYK_") }) { return "CMYK" }
+        if fieldNames.contains(where: { $0.hasPrefix("RGB_") }) { return "RGB" }
+        if fieldNames.contains(where: { $0.hasPrefix("LAB_") }) { return "LAB" }
+        if fieldNames.contains(where: { $0.hasPrefix("XYZ_") }) { return "XYZ" }
+        return nil
+    }
+
+    private static func inferDeviceClass(fieldNames: [String]) -> String? {
+        if fieldNames.contains(where: { $0.hasPrefix("CMYK_") }) { return "PRINTER" }
+        if fieldNames.contains(where: { $0.hasPrefix("RGB_") }) { return "DISPLAY" }
+        return "OUTPUT"
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/CGATS/CGATSSummary.swift

@@ -0,0 +1,20 @@
+import Foundation
+
+/// Human-readable summary of an imported CGATS dataset.
+public struct CGATSSummary: Sendable, Equatable {
+    public let patchCount: Int
+    public let colorSpace: String?
+    public let deviceClass: String?
+    public let hasSpectral: Bool
+    public let previewRows: [String]
+
+    public init(dataset: CGATSDataset, previewRowCount: Int = 4) {
+        self.patchCount = dataset.samples.count
+        self.colorSpace = dataset.colorRep
+        self.deviceClass = dataset.deviceClass
+        self.hasSpectral = dataset.fieldNames.contains { $0.hasPrefix("SPECTRAL_") }
+        self.previewRows = Array(dataset.samples.prefix(previewRowCount).map { sample in
+            "\(sample.id)" + (sample.loc.map { " \($0)" } ?? "")
+        })
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/CGATS/CGATSWriter.swift

@@ -0,0 +1,82 @@
+import Foundation
+
+/// Errors from writing a canonical `.ti3` dataset.
+public enum CGATSWriterError: Error, Equatable {
+    case noSamples
+    case missingRequiredField(String)
+    case invalidValue(field: String, value: String)
+}
+
+/// Write a `CGATSDataset` to Argyll-consumable `.ti3` text.
+public enum CGATSWriter {
+
+    public static func write(_ dataset: CGATSDataset) throws -> String {
+        guard !dataset.samples.isEmpty, !dataset.fieldNames.isEmpty else {
+            throw CGATSWriterError.noSamples
+        }
+
+        var lines = [String]()
+
+        // Header
+        lines.append(dataset.format.rawValue)
+        lines.append("")
+
+        lines.append("DESCRIPTOR \"ICCery CGATS export\"")
+        if let colorRep = dataset.colorRep {
+            lines.append("COLOR_REP \"\(colorRep)\"")
+        }
+        if let deviceClass = dataset.deviceClass {
+            lines.append("DEVICE_CLASS \"\(deviceClass)\"")
+        }
+        if let instrument = dataset.targetInstrument {
+            lines.append("TARGET_INSTRUMENT \"\(instrument)\"")
+        }
+
+        lines.append("NUMBER_OF_FIELDS \(dataset.fieldNames.count)")
+        lines.append("NUMBER_OF_SETS \(dataset.samples.count)")
+        lines.append("")
+
+        lines.append("BEGIN_DATA_FORMAT")
+        lines.append(dataset.fieldNames.joined(separator: "\t"))
+        lines.append("END_DATA_FORMAT")
+        lines.append("")
+
+        lines.append("BEGIN_DATA")
+        for sample in dataset.samples {
+            let row = try dataset.fieldNames.map { field in
+                guard let raw = sample.values[field], !raw.isEmpty else {
+                    throw CGATSWriterError.missingRequiredField(field)
+                }
+                // Normalize numeric fields to a compact decimal.
+                if isNumeric(field) {
+                    return normalizedNumber(raw)
+                }
+                return raw
+            }
+            lines.append(row.joined(separator: "\t"))
+        }
+        lines.append("END_DATA")
+
+        return lines.joined(separator: "\n") + "\n"
+    }
+
+    public static func write(_ dataset: CGATSDataset, to url: URL) throws {
+        let text = try write(dataset)
+        try text.write(to: url, atomically: true, encoding: .utf8)
+    }
+
+    // MARK: - Internals
+
+    private static func isNumeric(_ field: String) -> Bool {
+        let nonNumeric: Set = ["SAMPLE_ID", "SAMPLE_LOC", "SAMPLE_NAME"]
+        return !nonNumeric.contains(field)
+    }
+
+    private static func normalizedNumber(_ raw: String) -> String {
+        guard let number = Double(raw) else { return raw }
+        if number == floor(number) {
+            return String(format: "%.0f", number)
+        }
+        return String(format: "%.4f", number)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Files/ArtefactFiles.swift

@@ -0,0 +1,28 @@
+import Foundation
+
+/// Small host-side file helpers (issue #6).
+public enum ArtefactFiles {
+
+    /// `get_default_working_dir` — `resolveSafeCwd(nil)`.
+    public static func defaultWorkingDirectory() -> URL {
+        PathSecurity.resolveSafeCwd(nil)
+    }
+
+    /// `read_file_base64` — for **text artefacts** the UI needs verbatim
+    /// (ti1/ti2 previews, CGATS datasets, logs). Binary payloads (TIFF)
+    /// go through `TiffPreview` instead.
+    public static func readBase64(_ url: URL) throws -> String {
+        try Data(contentsOf: url).base64EncodedString()
+    }
+
+    /// `get_app_info` — version + build for the About dialog.
+    public static func appInfo(
+        bundle: Bundle = .main
+    ) -> (version: String, build: String) {
+        let info = bundle.infoDictionary ?? [:]
+        return (
+            info["CFBundleShortVersionString"] as? String ?? "0.0.0",
+            info["CFBundleVersion"] as? String ?? "0"
+        )
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Files/ArtefactProbe.swift

@@ -0,0 +1,112 @@
+import Foundation
+
+/// Result of `verify_stage_artefacts(cwd, basename)` (docs/06).
+public struct StageArtefacts: Sendable, Equatable {
+    /// `<basename>.ti1` exists (Stage 1 done → unlocks Stage 2).
+    public var stage1Complete = false
+    /// `<basename>.ti2` exists (Stage 2 done → with ti1, unlocks Stage 3).
+    public var stage2Complete = false
+    /// `<basename>.ti3` exists (Stage 3 done → unlocks Stage 4).
+    public var stage3Complete = false
+    /// `.icc`/`.icm` exists (Stage 4 done → with ti3, unlocks Stage 5).
+    public var stage4Complete = false
+    /// Absolute path of the profile file when present.
+    public var profilePath: URL?
+
+    public init(
+        stage1Complete: Bool = false,
+        stage2Complete: Bool = false,
+        stage3Complete: Bool = false,
+        stage4Complete: Bool = false,
+        profilePath: URL? = nil
+    ) {
+        self.stage1Complete = stage1Complete
+        self.stage2Complete = stage2Complete
+        self.stage3Complete = stage3Complete
+        self.stage4Complete = stage4Complete
+        self.profilePath = profilePath
+    }
+}
+
+/// Filesystem probing for wizard artefacts (docs/02 §Working directory,
+/// docs/06 §Stages). All artefacts live next to each other in `cwd`.
+public enum ArtefactProbe {
+
+    /// `verify_stage_artefacts` — the gating truth source.
+    public static func verify(
+        basename: String,
+        cwd: URL,
+        fileManager: FileManager = .default
+    ) -> StageArtefacts {
+        var out = StageArtefacts()
+        out.stage1Complete = exists(artefact(basename, "ti1", cwd), fm: fileManager)
+        out.stage2Complete = exists(artefact(basename, "ti2", cwd), fm: fileManager)
+        out.stage3Complete = exists(artefact(basename, "ti3", cwd), fm: fileManager)
+        if let profile = resolveProfile(basename: basename, cwd: cwd, fileManager: fileManager) {
+            out.stage4Complete = true
+            out.profilePath = profile
+        }
+        return out
+    }
+
+    /// `<cwd>/<basename>.<ext>` — the canonical artefact URL.
+    public static func artefact(_ basename: String, _ ext: String, _ cwd: URL) -> URL {
+        cwd.appendingPathComponent("\(basename).\(ext)", isDirectory: false)
+    }
+
+    /// Profile extension resolution (#69): existing `.icm` wins over
+    /// `.icc`; when neither exists the macOS default is `.icc`.
+    /// (`profcheck`/`iccgamut` swap extension when the requested path is
+    /// missing.)
+    public static func resolveProfile(
+        basename: String,
+        cwd: URL,
+        fileManager: FileManager = .default
+    ) -> URL? {
+        let icm = artefact(basename, "icm", cwd)
+        if exists(icm, fm: fileManager) { return icm }
+        let icc = artefact(basename, "icc", cwd)
+        if exists(icc, fm: fileManager) { return icc }
+        return nil
+    }
+
+    /// Default extension for a *new* profile on macOS (#69).
+    public static let defaultProfileExtension = "icc"
+
+    /// Every artefact path for a basename: `.ti1 .ti2 .tif .N.tif
+    /// .ti3 _passN.ti3 .icc .icm .gam` plus the `CAL_<basename>` namespace.
+    /// Multi-page TIFFs match `<basename>.tif`, `<basename>.1.tif` … and
+    /// `<basename>_NN.tif` (manifest naming).
+    public static func existingArtefacts(
+        basename: String,
+        cwd: URL,
+        fileManager: FileManager = .default
+    ) -> [URL] {
+        guard let entries = try? fileManager.contentsOfDirectory(
+            at: cwd,
+            includingPropertiesForKeys: nil,
+            options: [.skipsHiddenFiles]
+        ) else { return [] }
+
+        let prefixes = [basename + ".", "CAL_" + basename + "."]
+        let suffixes: Set<String> = ["ti1", "ti2", "tif", "ti3", "icc", "icm", "gam", "cal"]
+        let passPrefix = basename + "_pass"
+        let tifStemPrefix = basename + "_"
+        let calPrefix = "CAL_" + basename
+
+        return entries.filter { url in
+            let name = url.lastPathComponent
+            let ext = url.pathExtension.lowercased()
+            guard suffixes.contains(ext) else { return false }
+            if prefixes.contains(where: { name.hasPrefix($0) }) { return true }
+            if name.hasPrefix(passPrefix), ext == "ti3" { return true }
+            if name.hasPrefix(tifStemPrefix), ext == "tif" { return true }
+            if name.hasPrefix(calPrefix) { return true }
+            return false
+        }.sorted { $0.lastPathComponent < $1.lastPathComponent }
+    }
+
+    private static func exists(_ url: URL, fm: FileManager) -> Bool {
+        fm.fileExists(atPath: url.path)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Files/AtomicFileWriter.swift

@@ -0,0 +1,34 @@
+import Foundation
+
+/// Atomic `.tmp`-then-rename file writes — the convention used by
+/// settings.json, verification_history.json and wizard_state.json
+/// (docs/02 §Persistence, #213).
+public enum AtomicFileWriter {
+
+    /// Writes `data` to `url` atomically: sibling `<name>.tmp`, then a
+    /// rename (which is atomic on APFS/HFS+). Parent dirs are created.
+    public static func write(_ data: Data, to url: URL) throws {
+        let fm = FileManager.default
+        let dir = url.deletingLastPathComponent()
+        try fm.createDirectory(at: dir, withIntermediateDirectories: true)
+
+        let tmp = url.appendingPathExtension("tmp")
+        do {
+            try data.write(to: tmp, options: [])
+            // replaceItemAt handles same-volume atomic swap and removes
+            // the destination cleanly; fall back to remove+move.
+            if fm.fileExists(atPath: url.path) {
+                _ = try fm.replaceItemAt(url, withItemAt: tmp)
+            } else {
+                try fm.moveItem(at: tmp, to: url)
+            }
+        } catch {
+            try? fm.removeItem(at: tmp)
+            throw error
+        }
+    }
+
+    public static func write(_ text: String, to url: URL) throws {
+        try write(Data(text.utf8), to: url)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Files/PathSecurity.swift

@@ -0,0 +1,54 @@
+import Foundation
+
+/// Basename sanitisation and safe working-directory resolution
+/// (docs/02 §Working directory, docs/06 §Empty cwd).
+public enum PathSecurity {
+
+    public enum Error: Swift.Error, Equatable, Sendable {
+        case invalidBasename(String)
+    }
+
+    /// Basenames must not contain `/`, `\`, or `..` and must be
+    /// non-empty. Never invent a default basename (#60).
+    public static func isValidBasename(_ name: String) -> Bool {
+        guard !name.isEmpty else { return false }
+        return !name.contains("/") && !name.contains("\\") && !name.contains("..")
+    }
+
+    @discardableResult
+    public static func sanitizeBasename(_ name: String) throws -> String {
+        guard isValidBasename(name) else {
+            throw Error.invalidBasename(name)
+        }
+        return name
+    }
+
+    /// `resolve_safe_cwd` (docs/04 §0.2): explicit real directory →
+    /// Documents → Home → app-data. Never returns an empty/nil cwd.
+    public static func resolveSafeCwd(
+        _ explicit: URL?,
+        fileManager: FileManager = .default
+    ) -> URL {
+        if let explicit,
+           fileManager.fileExists(atPath: explicit.path, isDirectory: nil) {
+            return explicit
+        }
+        let candidates: [URL?] = [
+            fileManager.urls(for: .documentDirectory, in: .userDomainMask).first,
+            fileManager.homeDirectoryForCurrentUser,
+            AppPaths.appDataDir,
+        ]
+        for candidate in candidates {
+            guard let url = candidate else { continue }
+            if !fileManager.fileExists(atPath: url.path) {
+                try? fileManager.createDirectory(at: url, withIntermediateDirectories: true)
+            }
+            if fileManager.fileExists(atPath: url.path, isDirectory: nil) {
+                return url
+            }
+        }
+        // Last resort: app-data, created unconditionally.
+        try? fileManager.createDirectory(at: AppPaths.appDataDir, withIntermediateDirectories: true)
+        return AppPaths.appDataDir
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Files/Ti2Header.swift

@@ -0,0 +1,53 @@
+import Foundation
+
+/// Parsed header of a `.ti2` chart-layout file (docs/06 §Resume).
+/// `parse_ti2_header` reads only CGATS keyword lines — the data grid
+/// itself belongs to issue #30.
+public struct Ti2Header: Sendable, Equatable {
+    /// `TARGET_INSTRUMENT` (e.g. `i1`, `i1iO`, `CM`).
+    public var instrument: String?
+    /// `NUMBER_OF_SETS` — the patch count. Note: `NUMBER_OF_FIELDS` is
+    /// the CGATS column count, *not* the patch count.
+    public var patchCount: Int?
+    /// `NUMBER_OF_PAGES`.
+    public var pageCount: Int?
+    /// A sibling `<stem>.ti1` exists next to the parsed file.
+    public var hasSiblingTi1 = false
+
+    public static func parse(
+        _ url: URL,
+        fileManager: FileManager = .default
+    ) -> Ti2Header {
+        var header = Ti2Header()
+        guard let text = try? String(contentsOf: url, encoding: .utf8) else {
+            return header
+        }
+        for rawLine in text.split(whereSeparator: \.isNewline) {
+            let line = rawLine.trimmingCharacters(in: .whitespaces)
+            if line.hasPrefix("BEGIN_DATA_FORMAT") || line.hasPrefix("BEGIN_DATA") {
+                break
+            }
+            // CGATS keyword lines: `KEYWORD "value"` or `KEYWORD value`.
+            guard let space = line.firstIndex(of: " ") else { continue }
+            let key = String(line[..<space])
+            let value = String(line[line.index(after: space)...])
+                .trimmingCharacters(in: .whitespaces)
+                .trimmingCharacters(in: CharacterSet(charactersIn: "\""))
+            switch key {
+            case "TARGET_INSTRUMENT":
+                header.instrument = value
+            case "NUMBER_OF_SETS":
+                header.patchCount = Int(value)
+            case "NUMBER_OF_PAGES":
+                header.pageCount = Int(value)
+            default:
+                continue
+            }
+        }
+        let stem = url.deletingPathExtension()
+        header.hasSiblingTi1 = fileManager.fileExists(
+            atPath: stem.appendingPathExtension("ti1").path
+        )
+        return header
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Files/TiffPreview.swift

@@ -0,0 +1,38 @@
+import Foundation
+import ImageIO
+import UniformTypeIdentifiers
+
+/// TIFF → PNG preview for the Stage 2 gallery (#58): decode on the host
+/// side, cap the long edge at 1200 px, emit PNG. Never hand raw TIFF
+/// bytes to the UI.
+public enum TiffPreview {
+
+    public static let maxEdge: Int = 1200
+
+    /// Returns PNG data for the first page of a TIFF, or `nil` when the
+    /// file cannot be decoded.
+    public static func previewPNG(
+        tiff url: URL,
+        maxEdge: Int = Self.maxEdge
+    ) -> Data? {
+        guard let source = CGImageSourceCreateWithURL(url as CFURL, nil) else {
+            return nil
+        }
+        let options: [CFString: Any] = [
+            kCGImageSourceCreateThumbnailFromImageAlways: true,
+            kCGImageSourceThumbnailMaxPixelSize: maxEdge,
+            kCGImageSourceCreateThumbnailWithTransform: true,
+        ]
+        guard let image = CGImageSourceCreateThumbnailAtIndex(
+            source, 0, options as CFDictionary
+        ) else { return nil }
+
+        let out = NSMutableData()
+        guard let dest = CGImageDestinationCreateWithData(
+            out, UTType.png.identifier as CFString, 1, nil
+        ) else { return nil }
+        CGImageDestinationAddImage(dest, image, nil)
+        guard CGImageDestinationFinalize(dest) else { return nil }
+        return out as Data
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Logging/AppLogger.swift

@@ -0,0 +1,62 @@
+import Foundation
+import OSLog
+
+/// Severity levels, matching the v1 `log_level` setting values.
+public enum LogLevel: String, Codable, Sendable, CaseIterable {
+    case error, warn, info, debug, trace
+
+    var osType: OSLogType {
+        switch self {
+        case .error: return .error
+        case .warn:  return .default
+        case .info:  return .info
+        case .debug: return .debug
+        case .trace: return .debug
+        }
+    }
+
+    /// Lower rank = more severe. `shouldLog` keeps `rank <= min`.
+    var rank: Int {
+        switch self {
+        case .error: return 0
+        case .warn:  return 1
+        case .info:  return 2
+        case .debug: return 3
+        case .trace: return 4
+        }
+    }
+}
+
+/// Central logger: `os.Logger` + rolling file sink (`LogSink`), level
+/// gated at write time so a settings save takes effect immediately
+/// (#158).
+public struct AppLogger: Sendable {
+    public static let shared = AppLogger(category: "app")
+
+    private let osLog: Logger
+    private let sink: LogSink
+    public let category: String
+
+    public init(category: String, sink: LogSink = .shared) {
+        self.category = category
+        self.sink = sink
+        self.osLog = Logger(
+            subsystem: AppPaths.bundleIdentifier,
+            category: category
+        )
+    }
+
+    public func log(_ level: LogLevel, _ message: @autoclosure () -> String) {
+        let text = LogSanitizer.sanitize(message())
+        if level.rank <= sink.level.rank {
+            osLog.log(level: level.osType, "\(text, privacy: .public)")
+        }
+        sink.write(level: level, category: category, message: text)
+    }
+
+    public func error(_ message: @autoclosure () -> String) { log(.error, message()) }
+    public func warn(_ message: @autoclosure () -> String) { log(.warn, message()) }
+    public func info(_ message: @autoclosure () -> String) { log(.info, message()) }
+    public func debug(_ message: @autoclosure () -> String) { log(.debug, message()) }
+    public func trace(_ message: @autoclosure () -> String) { log(.trace, message()) }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Logging/LogSanitizer.swift

@@ -0,0 +1,17 @@
+import Foundation
+
+/// Rewrites the user's home directory to `~` in log output
+/// (docs/03 §Logging hygiene — `sanitize_arg_for_logging`).
+public enum LogSanitizer {
+    /// Replaces every occurrence of the current user's home path with `~`.
+    public static func sanitize(_ text: String) -> String {
+        let home = NSHomeDirectory()
+        guard !home.isEmpty else { return text }
+        return text.replacingOccurrences(of: home, with: "~")
+    }
+
+    /// Sanitizes an argv list for display.
+    public static func sanitizeArgs(_ args: [String]) -> String {
+        args.map(sanitize).joined(separator: " ")
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Logging/RollingFileLogger.swift

@@ -0,0 +1,127 @@
+import Foundation
+import OSLog
+
+/// Rolling file sink for `AppLogger` — `~/Library/Logs/<bundle>/
+/// iccery.log`, rotated at 5 MiB, keeping 5 historical segments
+/// (`iccery.log.1` … `iccery.log.5`).
+///
+/// The minimum level is **runtime state** (#158): `setLevel` takes
+/// effect immediately — at startup and on every settings save.
+public final class LogSink: @unchecked Sendable {
+
+    public static let shared = LogSink(fileURL: AppPaths.logFile)
+
+    private let lock = NSLock()
+    private let fileURL: URL
+    private var minimumLevel: LogLevel
+    private var handle: FileHandle?
+
+    /// 5 MiB per segment, 5 historical segments kept.
+    public static let maxSegmentBytes: UInt64 = 5 * 1024 * 1024
+    public static let keptSegments = 5
+
+    public init(
+        fileURL: URL = AppPaths.logFile,
+        minimumLevel: LogLevel? = nil
+    ) {
+        self.fileURL = fileURL
+        #if DEBUG
+        self.minimumLevel = minimumLevel ?? .debug
+        #else
+        self.minimumLevel = minimumLevel ?? .info
+        #endif
+    }
+
+    public var level: LogLevel {
+        lock.lock()
+        defer { lock.unlock() }
+        return minimumLevel
+    }
+
+    /// Applied at startup AND on every settings save (issue #5, #158).
+    public func setLevel(_ level: LogLevel) {
+        lock.lock()
+        minimumLevel = level
+        lock.unlock()
+    }
+
+    /// `nil` → DEBUG-build default (.debug) / release (.info).
+    public func applySettings(_ settings: AppSettings) {
+        setLevel(settings.effectiveLogLevel)
+    }
+
+    public func shouldLog(_ level: LogLevel) -> Bool {
+        level.rank <= { lock.lock(); defer { lock.unlock() }; return minimumLevel }().rank
+    }
+
+    // MARK: - Writing
+
+    /// Appends a `YYYY-MM-DD HH:mm:ss.SSS [LEVEL] category: msg` line,
+    /// rotating first when the active segment exceeds 5 MiB.
+    public func write(level: LogLevel, category: String, message: String) {
+        guard shouldLog(level) else { return }
+        lock.lock()
+        defer { lock.unlock() }
+        rotateIfNeeded()
+        openIfNeeded()
+        let stamp = Self.timestamp()
+        let line = "\(stamp) [\(level.rawValue.uppercased())] \(category): \(message)\n"
+        if let data = line.data(using: .utf8) {
+            handle?.write(data)
+        }
+    }
+
+    private static let formatter: DateFormatter = {
+        let f = DateFormatter()
+        f.dateFormat = "yyyy-MM-dd HH:mm:ss.SSS"
+        f.locale = Locale(identifier: "en_US_POSIX")
+        return f
+    }()
+
+    private static func timestamp() -> String {
+        formatter.string(from: Date())
+    }
+
+    private func openIfNeeded() {
+        guard handle == nil else { return }
+        try? FileManager.default.createDirectory(
+            at: fileURL.deletingLastPathComponent(), withIntermediateDirectories: true
+        )
+        if !FileManager.default.fileExists(atPath: fileURL.path) {
+            FileManager.default.createFile(atPath: fileURL.path, contents: nil)
+        }
+        handle = try? FileHandle(forWritingTo: fileURL)
+        try? handle?.seekToEnd()
+    }
+
+    /// Shifts `iccery.log.4→.5`, `.3→.4`, …, `.log→.1` and resets the
+    /// writer. Oldest segment is deleted.
+    private func rotateIfNeeded() {
+        guard FileManager.default.fileExists(atPath: fileURL.path),
+              let attrs = try? FileManager.default.attributesOfItem(atPath: fileURL.path),
+              let size = attrs[.size] as? UInt64,
+              size >= Self.maxSegmentBytes
+        else { return }
+
+        try? handle?.close()
+        handle = nil
+        let fm = FileManager.default
+        let oldest = fileURL.appendingPathExtension("\(Self.keptSegments)")
+        try? fm.removeItem(at: oldest)
+        for i in stride(from: Self.keptSegments - 1, through: 1, by: -1) {
+            let src = fileURL.appendingPathExtension("\(i)")
+            let dst = fileURL.appendingPathExtension("\(i + 1)")
+            if fm.fileExists(atPath: src.path) {
+                try? fm.moveItem(at: src, to: dst)
+            }
+        }
+        try? fm.moveItem(at: fileURL, to: fileURL.appendingPathExtension("1"))
+    }
+
+    /// Tail of the active log for the settings dialog's "copy excerpt".
+    public func tailExcerpt(maxBytes: Int = 32 * 1024) -> String {
+        guard let data = try? Data(contentsOf: fileURL) else { return "" }
+        let slice = data.suffix(maxBytes)
+        return String(decoding: slice, as: UTF8.self)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/AverageArgs.swift

@@ -0,0 +1,78 @@
+import Foundation
+
+/// Errors during `average` argv construction.
+public enum AverageArgError: LocalizedError, Equatable, Sendable {
+    case invalidBasename(String)
+    case invalidPassCount(Int)
+    case outputCollidesWithInput
+    case pathOutsideCwd(URL)
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidBasename(let name):
+            return "Invalid basename for average: \(name)"
+        case .invalidPassCount(let count):
+            return "Average requires at least 2 pass files, got \(count)"
+        case .outputCollidesWithInput:
+            return "Average output filename collides with one of the inputs"
+        case .pathOutsideCwd(let url):
+            return "Pass or output file is outside the working directory: \(url.path)"
+        }
+    }
+}
+
+/// Configuration for an `average` run.
+public struct AverageConfig: Sendable, Equatable {
+    public let workingDirectory: URL
+    public let basename: String
+    public let passFiles: [URL]
+
+    public init(
+        workingDirectory: URL,
+        basename: String,
+        passFiles: [URL]
+    ) {
+        self.workingDirectory = workingDirectory
+        self.basename = basename
+        self.passFiles = passFiles
+    }
+}
+
+/// Pure argv builder for Argyll's `average` tool.
+public enum AverageArgs {
+
+    /// Builds `average -v pass1 pass2 ... basename.ti3` with relative names.
+    public static func build(config: AverageConfig) throws -> [String] {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+
+        guard config.passFiles.count >= 2 else {
+            throw AverageArgError.invalidPassCount(config.passFiles.count)
+        }
+
+        let output = config.workingDirectory
+            .appendingPathComponent("\(cleanBasename).ti3")
+
+        var inputNames: [String] = []
+        for url in config.passFiles {
+            try validate(url, isIn: config.workingDirectory)
+            inputNames.append(url.lastPathComponent)
+        }
+
+        try validate(output, isIn: config.workingDirectory)
+        let outputName = output.lastPathComponent
+
+        guard !inputNames.contains(outputName) else {
+            throw AverageArgError.outputCollidesWithInput
+        }
+
+        return ["-v"] + inputNames + [outputName]
+    }
+
+    private static func validate(_ url: URL, isIn cwd: URL) throws {
+        let cwdPath = cwd.standardizedFileURL.path
+        let urlPath = url.deletingLastPathComponent().standardizedFileURL.path
+        guard urlPath == cwdPath else {
+            throw AverageArgError.pathOutsideCwd(url)
+        }
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/ChartreadArgs.swift

@@ -0,0 +1,28 @@
+import Foundation
+
+/// Pure argv builder for Argyll's `chartread` tool.
+public enum ChartreadArgs {
+
+    /// Builds `chartread` argv per the Gronod fork protocol.
+    ///
+    /// - Always `-v -u`.
+    /// - `-c N` is emitted only for `selectedPort != nil` and `N > 1`.
+    /// - `-Y l` is emitted only when `enableLEDs` is `true`.
+    /// - Basename is the last positional argument and is sanitized.
+    public static func build(config: ChartreadConfig) throws -> [String] {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+
+        var args: [String] = ["-v", "-u"]
+
+        if let port = config.selectedPort, port > 1 {
+            args.append(contentsOf: ["-c", "\(port)"])
+        }
+
+        if config.enableLEDs {
+            args.append(contentsOf: ["-Y", "l"])
+        }
+
+        args.append(cleanBasename)
+        return args
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/ChartreadClassifier.swift

@@ -0,0 +1,302 @@
+import Foundation
+
+/// Discrete states for the `chartread` interaction.
+public enum ChartreadState: String, Codable, Sendable, Equatable, CaseIterable {
+    case idle
+    case calibrating
+    case awaitingStrip
+    case reading
+    case allStripsRead
+    case warning
+    case promptContinue
+    case tablePlaceSheet
+    case tableAlign
+    case error
+    case finished
+}
+
+/// Extra metadata produced by classifying a single `chartread` stdout line.
+public struct ChartreadClassifyResult: Sendable, Equatable {
+    public let state: ChartreadState
+    /// Whether this line is an informational "remove last sheet" notice.
+    public let isRemoveSheetNotice: Bool
+    /// Parsed sheet index and total from "sheet N of M read ok" or "place sheet N of M".
+    public let sheetNumber: Int?
+    public let sheetTotal: Int?
+    /// Fiducial patch name from XY "locate patch X with the sight".
+    public let alignmentPatch: String?
+    /// When a warning asks for a specific key (e.g. `y` or `n`), the caller should send that key.
+    public let requestedWarningKey: String?
+    /// Whether the line is a continuation of a multi-line XY prompt.
+    public let isTableContinuation: Bool
+
+    public init(
+        state: ChartreadState,
+        isRemoveSheetNotice: Bool = false,
+        sheetNumber: Int? = nil,
+        sheetTotal: Int? = nil,
+        alignmentPatch: String? = nil,
+        requestedWarningKey: String? = nil,
+        isTableContinuation: Bool = false
+    ) {
+        self.state = state
+        self.isRemoveSheetNotice = isRemoveSheetNotice
+        self.sheetNumber = sheetNumber
+        self.sheetTotal = sheetTotal
+        self.alignmentPatch = alignmentPatch
+        self.requestedWarningKey = requestedWarningKey
+        self.isTableContinuation = isTableContinuation
+    }
+}
+
+/// Pure line classifier for `chartread` stdout.
+///
+/// Matchers are evaluated in strict priority order (docs/04 §3.5, docs/05 §12.6).
+/// XY table continuation lines stay sticky in `TABLE_PLACE_SHEET` / `TABLE_ALIGN`.
+public enum ChartreadClassifier {
+
+    private typealias Matcher = (String, ChartreadState) -> ChartreadClassifyResult?
+
+    public static func classify(
+        line: String,
+        previousState: ChartreadState
+    ) -> ChartreadClassifyResult {
+        let text = line.lowercased()
+
+        for matcher in matchers(previousState) {
+            if let result = matcher(text, previousState) {
+                return result
+            }
+        }
+
+        return ChartreadClassifyResult(state: previousState)
+    }
+
+    private static func matchers(_ previous: ChartreadState) -> [Matcher] {
+        [
+            removeSheetNotice,
+            sheetReadOk,
+            locatePatch,
+            placeSheet,
+            continuation(previous),
+            done,
+            warning,
+            calibration,
+            awaitingStrip,
+            reading,
+            error
+        ]
+    }
+
+    // 1. "Please remove last sheet from table" — info only.
+    private static func removeSheetNotice(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        guard text.contains("remove") && text.contains("last") && text.contains("sheet") else { return nil }
+        return ChartreadClassifyResult(state: previous, isRemoveSheetNotice: true)
+    }
+
+    // 2. "Sheet N of M read OK".
+    private static func sheetReadOk(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        guard let match = text.firstMatch(pattern: #"sheet\s+(\d+)\s+of\s+(\d+)\s+read\s+ok"#) else { return nil }
+        return ChartreadClassifyResult(
+            state: previous,
+            sheetNumber: match.1,
+            sheetTotal: match.2
+        )
+    }
+
+    // 3. "locate patch X with the sight".
+    private static func locatePatch(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        guard let match = text.firstMatch(pattern: #"locate\s+patch\s+([a-z0-9_]+)\s+with"#),
+              !match.0.isEmpty else { return nil }
+        return ChartreadClassifyResult(
+            state: .tableAlign,
+            alignmentPatch: match.0.uppercased()
+        )
+    }
+
+    // 4. "place sheet N of M" or "remove previous sheet".
+    private static func placeSheet(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        if let match = text.firstMatch(pattern: #"place\s+sheet\s+(\d+)\s+of\s+(\d+)"#) {
+            return ChartreadClassifyResult(
+                state: .tablePlaceSheet,
+                sheetNumber: match.1,
+                sheetTotal: match.2
+            )
+        }
+        if text.contains("remove previous sheet") || text.contains("place sheet") {
+            return ChartreadClassifyResult(state: .tablePlaceSheet)
+        }
+        return nil
+    }
+
+    // 5. "hit return to continue" — sticky if already in a table state.
+    private static func continuation(_ previous: ChartreadState) -> Matcher {
+        return { text, _ in
+            guard text.contains("hit return to continue")
+                    || text.contains("hit any key to continue")
+                    || text.contains("hit space to continue")
+            else { return nil }
+
+            if case .tablePlaceSheet = previous {
+                return ChartreadClassifyResult(state: .tablePlaceSheet, isTableContinuation: true)
+            }
+            if case .tableAlign = previous {
+                return ChartreadClassifyResult(state: .tableAlign, isTableContinuation: true)
+            }
+
+            return ChartreadClassifyResult(state: .promptContinue, isTableContinuation: true)
+        }
+    }
+
+    // 6. Done / all read.
+    private static func done(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        let phrases = [
+            "'d' if/when done", "d to finish/save", "all strips/patches read",
+            "all strips read", "all patches read", "done reading",
+            "'d' to save", "press d to", "hit 'd'", "d to finish", "d to save"
+        ]
+        if phrases.contains(where: { text.contains($0) }) {
+            return ChartreadClassifyResult(state: .allStripsRead)
+        }
+        return nil
+    }
+
+    // 7. Warnings / prompts needing a key.
+    private static func warning(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        let lower = text
+        let warningSignals = [
+            "(warning)", "use it anyway", "seem to have read strip",
+            "unexpected response", "try again", "do you want to",
+            "abort ? - are you sure", "are you sure"
+        ]
+
+        let isWarningPrompt =
+            warningSignals.contains(where: { lower.contains($0) })
+            || lower.contains("(y/n)")
+            || lower.contains("'y' or 'n'")
+            || lower.contains("?")
+
+        guard isWarningPrompt else { return nil }
+
+        var key: String?
+        if lower.contains("(y/n)") || lower.contains("'y' or 'n'") {
+            // Default to asking the user; no automatic key.
+            key = nil
+        } else if lower.contains("'y'") || lower.contains("press y") || lower.contains("hit 'y'") {
+            key = "y"
+        } else if lower.contains("'n'") || lower.contains("press n") || lower.contains("hit 'n'") {
+            key = "n"
+        }
+
+        return ChartreadClassifyResult(state: .warning, requestedWarningKey: key)
+    }
+
+    // 8. Calibration / place reference / white / standard tile.
+    private static func calibration(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        let lowercased = text.lowercased()
+        let placeTokens = ["place", "reference", "white", "calibrat", "standard"]
+        let hasPlaceSheet = lowercased.contains("place sheet") || lowercased.contains("remove previous sheet")
+        let hasLocate = lowercased.contains("locate patch")
+
+        guard placeTokens.contains(where: { lowercased.contains($0) }),
+              !hasPlaceSheet,
+              !hasLocate
+        else { return nil }
+
+        if lowercased.contains("calibrat")
+            || lowercased.contains("white reference")
+            || lowercased.contains("white tile")
+            || lowercased.contains("standard tile")
+            || lowercased.contains("reference")
+            || lowercased.contains("tile")
+            || lowercased.contains("hit any key to continue")
+            || lowercased.contains("hit space to continue") {
+            return ChartreadClassifyResult(state: .calibrating)
+        }
+        return nil
+    }
+
+    // 9. Awaiting strip.
+    private static func awaitingStrip(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        let lowercased = text.lowercased()
+
+        // These are explicit, multi-word prompts; we deliberately do NOT
+        // match bare "read strip" so that error lines like
+        // "failed to read strip" or "error reading strip" fall through to
+        // the error matcher.
+        let phrases = [
+            "ready to read",
+            "hit any key to read",
+            "hit a key to read",
+            "hit space to read",
+            "hit [space] to read",
+            "press any key to read",
+            "press space to read",
+            "trigger instrument",
+            "start reading",
+            "read next strip"
+        ]
+
+        // Also permit "hit X to read strip Y" or "ready to read strip Z".
+        if lowercased.range(of: #"(hit|press).+to\s+read\s+strip"#, options: .regularExpression) != nil {
+            return ChartreadClassifyResult(state: .awaitingStrip)
+        }
+
+        guard phrases.contains(where: { lowercased.contains($0) }) else { return nil }
+        return ChartreadClassifyResult(state: .awaitingStrip)
+    }
+
+    // 10. Reading.
+    private static func reading(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        let lowercased = text.lowercased()
+        let phrases = ["reading strip", "reading sheet", "processing", "scanning", "reading..."]
+        guard phrases.contains(where: { lowercased.contains($0) }) else { return nil }
+        return ChartreadClassifyResult(state: .reading)
+    }
+
+    // 11. Error.
+    private static func error(text: String, previous: ChartreadState) -> ChartreadClassifyResult? {
+        let lower = text.lowercased()
+
+        // Avoid false positives from confirmation prompts and "no error" status.
+        guard !lower.contains("no error") else { return nil }
+        guard !lower.contains("(y/n)")
+              && !lower.contains("'y' or 'n'")
+              && !lower.contains("?")
+        else { return nil }
+
+        let phraseMatches = ["failed to read", "error reading", "too fast", "too slow", "misread"]
+        for phrase in phraseMatches {
+            if lower.contains(phrase) {
+                return ChartreadClassifyResult(state: .error)
+            }
+        }
+
+        // Whole-word "error" only — bare "failed" alone is not enough.
+        if lower.range(of: #"\berror\b"#, options: .regularExpression) != nil {
+            return ChartreadClassifyResult(state: .error)
+        }
+
+        return nil
+    }
+}
+
+private extension String {
+    func firstMatch(pattern: String) -> (String, Int, Int)? {
+        guard let regex = try? NSRegularExpression(pattern: pattern, options: .caseInsensitive),
+              let match = regex.firstMatch(in: self, options: [], range: NSRange(self.startIndex..., in: self))
+        else { return nil }
+
+        let groups: [String] = (1..<match.numberOfRanges).compactMap { i in
+            let r = match.range(at: i)
+            guard r.location != NSNotFound, let range = Range(r, in: self) else { return nil }
+            return String(self[range])
+        }
+
+        guard let first = groups.first else { return nil }
+        let ints = groups.compactMap { Int($0) }
+        let a = ints.count > 0 ? ints[0] : 0
+        let b = ints.count > 1 ? ints[1] : 0
+        return (first, a, b)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/ChartreadConfig.swift

@@ -0,0 +1,45 @@
+import Foundation
+
+/// Errors during `ChartreadArgs` validation.
+public enum ChartreadArgError: LocalizedError, Equatable {
+    case invalidBasename(String)
+    case invalidPort(Int)
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidBasename(let name):
+            return "Invalid chart basename: \(name)"
+        case .invalidPort(let port):
+            return "Invalid chartread port: \(port)"
+        }
+    }
+}
+
+/// Configuration for a `chartread` invocation.
+public struct ChartreadConfig: Codable, Equatable, Sendable {
+    public var basename: String
+    public var workingDirectory: URL?
+    /// Communication port to pass to `chartread -c`.
+    /// `nil` means omit `-c` (Auto or port 1).
+    public var selectedPort: Int?
+    /// Enable i1Pro 2 visual LEDs (`-Y l`).
+    public var enableLEDs: Bool
+
+    public init(
+        basename: String,
+        workingDirectory: URL? = nil,
+        selectedPort: Int? = nil,
+        enableLEDs: Bool = false,
+        isXY: Bool = false
+    ) {
+        self.basename = basename
+        self.workingDirectory = workingDirectory
+        self.selectedPort = selectedPort
+        self.enableLEDs = enableLEDs
+        self.isXY = isXY
+    }
+
+    /// Whether the current config implies an XY-table workflow.
+    /// This is normally supplied by the view model from the selected instrument.
+    public var isXY: Bool = false
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/ChartreadRow.swift

@@ -0,0 +1,143 @@
+import Foundation
+
+/// A single patch read by `chartread`.
+public struct ChartreadPatch: Codable, Sendable, Equatable {
+    public let id: String
+    public let loc: String
+    public let isPad: Bool
+    public let device: [Double]
+    public let expected: PatchColor?
+    public let measured: PatchColor
+
+    public init(
+        id: String,
+        loc: String,
+        isPad: Bool,
+        device: [Double],
+        expected: PatchColor?,
+        measured: PatchColor
+    ) {
+        self.id = id
+        self.loc = loc
+        self.isPad = isPad
+        self.device = device
+        self.expected = expected
+        self.measured = measured
+    }
+
+    enum CodingKeys: String, CodingKey {
+        case id, loc
+        case isPad = "is_pad"
+        case device, expected, measured
+    }
+}
+
+/// Colour payload carried by `expected` or `measured`.
+public struct PatchColor: Codable, Sendable, Equatable {
+    public let xyz: CIEXYZ?
+    public let lab: CIELab?
+    public let spectral: SpectralData?
+
+    public init(xyz: CIEXYZ? = nil, lab: CIELab? = nil, spectral: SpectralData? = nil) {
+        self.xyz = xyz
+        self.lab = lab
+        self.spectral = spectral
+    }
+
+    enum CodingKeys: String, CodingKey {
+        case xyz = "XYZ"
+        case lab = "Lab"
+        case spectral = "spectral"
+    }
+}
+
+public struct CIEXYZ: Codable, Sendable, Equatable {
+    public let x: Double
+    public let y: Double
+    public let z: Double
+
+    public init(from decoder: Decoder) throws {
+        var container = try decoder.unkeyedContainer()
+        self.x = try container.decode(Double.self)
+        self.y = try container.decode(Double.self)
+        self.z = try container.decode(Double.self)
+    }
+
+    public init(x: Double, y: Double, z: Double) {
+        self.x = x
+        self.y = y
+        self.z = z
+    }
+
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.unkeyedContainer()
+        try container.encode(x)
+        try container.encode(y)
+        try container.encode(z)
+    }
+}
+
+public struct CIELab: Codable, Sendable, Equatable {
+    public let l: Double
+    public let a: Double
+    public let b: Double
+
+    public init(from decoder: Decoder) throws {
+        var container = try decoder.unkeyedContainer()
+        self.l = try container.decode(Double.self)
+        self.a = try container.decode(Double.self)
+        self.b = try container.decode(Double.self)
+    }
+
+    public init(l: Double, a: Double, b: Double) {
+        self.l = l
+        self.a = a
+        self.b = b
+    }
+
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.unkeyedContainer()
+        try container.encode(l)
+        try container.encode(a)
+        try container.encode(b)
+    }
+}
+
+public struct SpectralData: Codable, Sendable, Equatable {
+    public let bands: Int
+    public let startNM: Double
+    public let endNM: Double
+    public let norm: Double
+    public let values: [Double]
+
+    enum CodingKeys: String, CodingKey {
+        case bands
+        case startNM = "start_nm"
+        case endNM = "end_nm"
+        case norm
+        case values
+    }
+}
+
+/// A complete row emitted by `chartread -u`.
+public struct ChartreadRow: Codable, Sendable, Equatable {
+    public let event: String
+    public let rowId: String
+    public let rowIndex: Int
+    public let totalRows: Int
+    public let patchCount: Int
+    public let patches: [ChartreadPatch]
+
+    enum CodingKeys: String, CodingKey {
+        case event
+        case rowId = "row_id"
+        case rowIndex = "row_index"
+        case totalRows = "total_rows"
+        case patchCount = "patch_count"
+        case patches
+    }
+
+    public var isFinalRow: Bool {
+        rowIndex + 1 >= totalRows
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/ColorDifference.swift

@@ -0,0 +1,174 @@
+import Foundation
+
+/// Result of evaluating one measured patch.
+public struct SwatchEvaluation: Sendable, Equatable {
+    public let intended: DisplayRGB
+    public let measured: DisplayRGB
+    public let deltaE: Double?
+    public let classification: SwatchClassification
+
+    public init(
+        intended: DisplayRGB,
+        measured: DisplayRGB,
+        deltaE: Double?,
+        classification: SwatchClassification
+    ) {
+        self.intended = intended
+        self.measured = measured
+        self.deltaE = deltaE
+        self.classification = classification
+    }
+}
+
+public enum SwatchClassification: String, Sendable, Equatable, CaseIterable {
+    case good
+    case warning
+    case bad
+}
+
+/// CIEDE2000 ΔE₀₀ between two D50 Lab values.
+public enum ColorDifference {
+
+    /// Compute ΔE₀₀ using the full CIEDE2000 formula.
+    public static func deltaE00(_ lab1: LabColor, _ lab2: LabColor) -> Double {
+        let kL: Double = 1
+        let kC: Double = 1
+        let kH: Double = 1
+
+        let c1 = sqrt(lab1.a * lab1.a + lab1.b * lab1.b)
+        let c2 = sqrt(lab2.a * lab2.a + lab2.b * lab2.b)
+
+        let cBar = (c1 + c2) / 2.0
+        let cBar7 = pow(cBar, 7)
+        let g = 0.5 * (1 - sqrt(cBar7 / (cBar7 + pow(25, 7))))
+
+        let a1p = (1 + g) * lab1.a
+        let a2p = (1 + g) * lab2.a
+
+        let c1p = sqrt(a1p * a1p + lab1.b * lab1.b)
+        let c2p = sqrt(a2p * a2p + lab2.b * lab2.b)
+
+        let h1p = atan2ToDegrees(lab1.b, a1p)
+        let h2p = atan2ToDegrees(lab2.b, a2p)
+
+        let deltaLp = lab2.l - lab1.l
+        let deltaCp = c2p - c1p
+
+        var deltaHp: Double = 0
+        if c1p * c2p == 0 {
+            deltaHp = 0
+        } else {
+            let diff = h2p - h1p
+            if abs(diff) <= 180 {
+                deltaHp = diff
+            } else if diff > 180 {
+                deltaHp = diff - 360
+            } else {
+                deltaHp = diff + 360
+            }
+        }
+
+        let deltaHp2 = 2 * sqrt(c1p * c2p) * sin(deltaHp * .pi / 360.0)
+
+        let lBarp = (lab1.l + lab2.l) / 2.0
+        let cBarp = (c1p + c2p) / 2.0
+
+        var hBarp: Double
+        if c1p * c2p == 0 {
+            hBarp = h1p + h2p
+        } else {
+            if abs(h1p - h2p) <= 180 {
+                hBarp = (h1p + h2p) / 2.0
+            } else if h1p + h2p < 360 {
+                hBarp = (h1p + h2p + 360) / 2.0
+            } else {
+                hBarp = (h1p + h2p - 360) / 2.0
+            }
+        }
+
+        let t = 1
+            - 0.17 * cos(deg2rad(hBarp - 30))
+            + 0.24 * cos(deg2rad(2 * hBarp))
+            + 0.32 * cos(deg2rad(3 * hBarp + 6))
+            - 0.20 * cos(deg2rad(4 * hBarp - 63))
+
+        let dTheta = 30 * exp(-pow((hBarp - 275) / 25, 2))
+        let cBarp7 = pow(cBarp, 7)
+        let rc = 2 * sqrt(cBarp7 / (cBarp7 + pow(25, 7)))
+
+        let sl = 1 + (0.015 * pow(lBarp - 50, 2)) / sqrt(20 + pow(lBarp - 50, 2))
+        let sc = 1 + 0.045 * cBarp
+        let sh = 1 + 0.015 * cBarp * t
+
+        let rt = -sin(deg2rad(2 * dTheta)) * rc
+
+        let lTerm = deltaLp / (kL * sl)
+        let cTerm = deltaCp / (kC * sc)
+        let hTerm = deltaHp2 / (kH * sh)
+
+        return sqrt(
+            lTerm * lTerm
+            + cTerm * cTerm
+            + hTerm * hTerm
+            + rt * cTerm * hTerm
+        )
+    }
+
+    /// Classify a ΔE value against user thresholds.
+    public static func classify(deltaE: Double, goodMax: Double, warningMax: Double) -> SwatchClassification {
+        if deltaE < goodMax { return .good }
+        if deltaE < warningMax { return .warning }
+        return .bad
+    }
+
+    /// Evaluate a patch: compute intended/measured sRGB and ΔE if both Lab values are present.
+    public static func evaluate(
+        patch: ChartreadPatch,
+        goodMax: Double,
+        warningMax: Double
+    ) -> SwatchEvaluation? {
+        guard let measured = resolveLab(patch.measured) else { return nil }
+
+        let measuredRGB = LabColorMath.labToSRGB(measured)
+
+        if let expectedColor = patch.expected,
+           let expectedLab = resolveLab(expectedColor) {
+            let de = deltaE00(expectedLab, measured)
+            let intendedRGB = LabColorMath.labToSRGB(expectedLab)
+            return SwatchEvaluation(
+                intended: intendedRGB,
+                measured: measuredRGB,
+                deltaE: de,
+                classification: classify(deltaE: de, goodMax: goodMax, warningMax: warningMax)
+            )
+        } else {
+            // No reference: still render measured colour, no ΔE.
+            return SwatchEvaluation(
+                intended: measuredRGB,
+                measured: measuredRGB,
+                deltaE: nil,
+                classification: .good
+            )
+        }
+    }
+
+    /// Resolve a Lab from a `PatchColor`, computing it from XYZ when Lab is absent.
+    public static func resolveLab(_ color: PatchColor) -> LabColor? {
+        if let lab = color.lab {
+            return LabColor(l: lab.l, a: lab.a, b: lab.b)
+        }
+        guard let xyz = color.xyz else { return nil }
+        return LabColorMath.xyzToLab(XYZColor(x: xyz.x, y: xyz.y, z: xyz.z))
+    }
+
+    private static func atan2ToDegrees(_ y: Double, _ x: Double) -> Double {
+        let radians = atan2(y, x)
+        var degrees = radians * 180.0 / .pi
+        if degrees < 0 { degrees += 360 }
+        return degrees
+    }
+
+    private static func deg2rad(_ degrees: Double) -> Double {
+        degrees * .pi / 180.0
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/InstrumentModels.swift

@@ -0,0 +1,58 @@
+import Foundation
+
+/// A device discovered by the Argyll `instlist` fork.
+public struct InstrumentDevice: Codable, Sendable, Equatable, Identifiable {
+    public let port: Int
+    public let name: String
+    public let type: String
+
+    public init(port: Int, name: String, type: String) {
+        self.port = port
+        self.name = name
+        self.type = type
+    }
+
+    public var id: Int { port }
+
+    /// XY tables are identified by name or type matching the fork pattern.
+    public var isXY: Bool {
+        let combined = "\(name) \(type)".lowercased()
+        let pattern = #"/spectro\s?scan|i1io/"#
+        return combined.range(of: pattern, options: .regularExpression) != nil
+    }
+
+    /// Human-readable label shown in the picker.
+    public var displayName: String {
+        let xyTag = isXY ? " · XY Table" : ""
+        return "\(name) [\(type)]\(xyTag)"
+    }
+}
+
+/// The user’s choice for a chartread session.
+public enum InstrumentSelection: Sendable, Equatable {
+    /// Auto / first available port — `chartread` omits `-c`.
+    case auto
+    /// A concrete instrument.
+    case device(InstrumentDevice)
+
+    /// The value to pass to `chartread -c`.
+    /// `nil` means omit `-c` (port 1 and Auto both map to no flag).
+    public var chartreadPort: Int? {
+        switch self {
+        case .auto:
+            return nil
+        case .device(let device):
+            return device.port == 1 ? nil : device.port
+        }
+    }
+
+    /// Whether the current selection implies an XY table workflow.
+    public var isXY: Bool {
+        switch self {
+        case .auto:
+            return false
+        case .device(let device):
+            return device.isXY
+        }
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/InstrumentParser.swift

@@ -0,0 +1,72 @@
+import Foundation
+
+/// Errors from `instlist` output parsing.
+public enum InstrumentParserError: Error, Sendable, Equatable {
+    case malformedJSON
+    case missingDevices
+    case invalidPort
+}
+
+/// Parses the Argyll `instlist` stdout document.
+///
+/// Fork `instlist` emits pretty-printed JSON with the shape
+/// `{ "event": "instruments", "devices": [ { "port": 1, "name": "...", "type": "..." } ] }`.
+/// If JSON decoding fails, a constrained regex fallback is used.
+/// Only lines accepted by the fallback must also match known instrument tokens.
+public enum InstrumentParser {
+
+    /// Known instrument tokens used by the regex fallback.
+    public static let knownInstrumentPattern =
+        #"i1|ColorMunki|Spyder|spectro|Display|Huey|DTP|SpectroScan|Smile|Klein"#
+
+    /// Parse the complete `instlist` output.
+    public static func parse(_ output: String) throws -> [InstrumentDevice] {
+        let trimmed = output.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !trimmed.isEmpty else { return [] }
+
+        if let data = trimmed.data(using: .utf8),
+           let decoded = try? decodeJSON(data) {
+            return decoded
+        }
+
+        let regex = try? NSRegularExpression(
+            pattern: #"^(\d+)[\s:=]+'?([^'\n]+)'?(?:\s+on\s+'?([^'\n]+)'?)?"#,
+            options: [.caseInsensitive, .anchorsMatchLines]
+        )
+        var devices: [InstrumentDevice] = []
+        let range = NSRange(trimmed.startIndex..., in: trimmed)
+        let matches = regex?.matches(in: trimmed, options: [], range: range) ?? []
+
+        for match in matches {
+            guard let portString = substring(trimmed, range: match.range(at: 1)),
+                  let port = Int(portString), port > 0 else { continue }
+
+            let name = substring(trimmed, range: match.range(at: 2))?.trimmingCharacters(in: .whitespacesAndNewlines) ?? ""
+            let type = substring(trimmed, range: match.range(at: 3))?.trimmingCharacters(in: .whitespacesAndNewlines) ?? ""
+
+            let combined = "\(name) \(type)".lowercased()
+            guard combined.range(of: knownInstrumentPattern,
+                                 options: [.regularExpression, .caseInsensitive]) != nil,
+                  !name.isEmpty else { continue }
+
+            devices.append(InstrumentDevice(port: port, name: name, type: type))
+        }
+
+        return devices
+    }
+
+    private static func decodeJSON(_ data: Data) throws -> [InstrumentDevice] {
+        let output = try JSONDecoder().decode(InstlistOutput.self, from: data)
+        return output.devices
+    }
+
+    private static func substring(_ source: String, range: NSRange) -> String? {
+        guard range.location != NSNotFound, let r = Range(range, in: source) else { return nil }
+        return String(source[r])
+    }
+}
+
+private struct InstlistOutput: Decodable {
+    let event: String
+    let devices: [InstrumentDevice]
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/LabColor.swift

@@ -0,0 +1,184 @@
+import Foundation
+
+/// XYZ tristimulus values, stored in the 0–100 scale used by the Argyll fork.
+public struct XYZColor: Sendable, Equatable {
+    public let x: Double
+    public let y: Double
+    public let z: Double
+
+    public init(x: Double, y: Double, z: Double) {
+        self.x = x
+        self.y = y
+        self.z = z
+    }
+}
+
+/// CIELab value (D50).
+public struct LabColor: Sendable, Equatable {
+    public let l: Double
+    public let a: Double
+    public let b: Double
+
+    public init(l: Double, a: Double, b: Double) {
+        self.l = l
+        self.a = a
+        self.b = b
+    }
+}
+
+/// sRGB colour in 0–1 display space.
+public struct DisplayRGB: Sendable, Equatable {
+    public let r: Double
+    public let g: Double
+    public let b: Double
+
+    public init(r: Double, g: Double, b: Double) {
+        self.r = r
+        self.g = g
+        self.b = b
+    }
+
+    public var clamped: DisplayRGB {
+        DisplayRGB(r: min(1, max(0, r)), g: min(1, max(0, g)), b: min(1, max(0, b)))
+    }
+}
+
+/// Colour-space conversions used by the swatch grid.
+///
+/// All numeric paths are deterministic and avoid platform colour-management APIs.
+public enum LabColorMath {
+
+    // Reference white for D50 (0–100 scale).
+    static let d50White = (X: 96.4212, Y: 100.0, Z: 82.5188)
+
+    // Reference white for D65 (0–100 scale).
+    static let d65White = (X: 95.0489, Y: 100.0, Z: 108.8840)
+
+    // Bradford cone-response matrix and its inverse (XYZ -> LMS).
+    static let bradford = [
+        [ 0.8951,  0.2664, -0.1614],
+        [-0.7502,  1.7135,  0.0367],
+        [ 0.0389, -0.0685,  1.0296]
+    ]
+
+    static let bradfordInv = [
+        [ 0.9869929, -0.1470543,  0.1599627],
+        [ 0.4323053,  0.5183603,  0.0492912],
+        [-0.0085287,  0.0400428,  0.9684866]
+    ]
+
+    // sRGB D65 matrix (XYZ -> linear sRGB, using 0–100 inputs).
+    static let srgbMatrix = [
+        [ 3.2406, -1.5372, -0.4986],
+        [-0.9689,  1.8758,  0.0415],
+        [ 0.0557, -0.2040,  1.0570]
+    ]
+
+    /// Convert XYZ (0–100) to CIELab D50.
+    public static func xyzToLab(_ xyz: XYZColor) -> LabColor {
+        let f: (Double) -> Double = { t in
+            let delta = 6.0 / 29.0
+            if t > delta * delta * delta {
+                return pow(t, 1.0 / 3.0)
+            } else {
+                return t / (3 * delta * delta) + 4.0 / 29.0
+            }
+        }
+
+        let x = f(xyz.x / d50White.X)
+        let y = f(xyz.y / d50White.Y)
+        let zr = f(xyz.z / d50White.Z)
+
+        return LabColor(
+            l: 116.0 * y - 16.0,
+            a: 500.0 * (x - y),
+            b: 200.0 * (y - zr)
+        )
+    }
+
+    /// Convert CIELab D50 to XYZ (0–100).
+    public static func labToXYZ(_ lab: LabColor) -> XYZColor {
+        let finv: (Double) -> Double = { t in
+            let delta = 6.0 / 29.0
+            if t > delta {
+                return t * t * t
+            } else {
+                return 3 * delta * delta * (t - 4.0 / 29.0)
+            }
+        }
+
+        let yr = (lab.l + 16.0) / 116.0
+        let xr = yr + lab.a / 500.0
+        let zr = yr - lab.b / 200.0
+
+        return XYZColor(
+            x: finv(xr) * d50White.X,
+            y: finv(yr) * d50White.Y,
+            z: finv(zr) * d50White.Z
+        )
+    }
+
+    /// Convert XYZ D50 to XYZ D65 using the Bradford chromatic adaptation.
+    public static func adaptD50ToD65(_ xyz: XYZColor) -> XYZColor {
+        let source = matrixMultiply(bradford, [xyz.x, xyz.y, xyz.z])
+        let srcWhite = matrixMultiply(bradford, [d50White.X, d50White.Y, d50White.Z])
+        let dstWhite = matrixMultiply(bradford, [d65White.X, d65White.Y, d65White.Z])
+
+        let scaled = [
+            source[0] * (dstWhite[0] / srcWhite[0]),
+            source[1] * (dstWhite[1] / srcWhite[1]),
+            source[2] * (dstWhite[2] / srcWhite[2])
+        ]
+
+        return XYZColor(
+            x: scaled[0] * bradfordInv[0][0] + scaled[1] * bradfordInv[0][1] + scaled[2] * bradfordInv[0][2],
+            y: scaled[0] * bradfordInv[1][0] + scaled[1] * bradfordInv[1][1] + scaled[2] * bradfordInv[1][2],
+            z: scaled[0] * bradfordInv[2][0] + scaled[1] * bradfordInv[2][1] + scaled[2] * bradfordInv[2][2]
+        )
+    }
+
+    /// Convert XYZ D65 (0–100) to linear sRGB, apply gamma, and clamp.
+    public static func xyzToSRGB(_ xyz: XYZColor) -> DisplayRGB {
+        // sRGB matrix is defined for XYZ with D65 white at Y = 1.0.
+        // The input is 0–100, so scale by 100 first.
+        let scaled = [xyz.x / 100.0, xyz.y / 100.0, xyz.z / 100.0]
+        let linear = matrixMultiply(srgbMatrix, scaled)
+
+        func gamma(_ c: Double) -> Double {
+            if c <= 0.0031308 {
+                return 12.92 * c
+            } else {
+                return 1.055 * pow(c, 1.0 / 2.4) - 0.055
+            }
+        }
+
+        return DisplayRGB(
+            r: gamma(linear[0]),
+            g: gamma(linear[1]),
+            b: gamma(linear[2])
+        ).clamped
+    }
+
+    /// Complete D50 Lab -> display sRGB conversion.
+    public static func labToSRGB(_ lab: LabColor) -> DisplayRGB {
+        let xyz50 = labToXYZ(lab)
+        let xyz65 = adaptD50ToD65(xyz50)
+        return xyzToSRGB(xyz65)
+    }
+
+    /// Convert an Argyll XYZ array (0–100) to Lab and then to sRGB.
+    public static func xyzArrayToSRGB(_ xyz: [Double]) -> DisplayRGB? {
+        guard xyz.count >= 3 else { return nil }
+        return labToSRGB(xyzToLab(XYZColor(x: xyz[0], y: xyz[1], z: xyz[2])))
+    }
+
+    private static func matrixMultiply(_ m: [[Double]], _ v: [Double]) -> [Double] {
+        var result = [Double](repeating: 0, count: m.count)
+        for i in 0..<m.count {
+            for j in 0..<v.count {
+                result[i] += m[i][j] * v[j]
+            }
+        }
+        return result
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Measurement/MeasurementArtefacts.swift

@@ -0,0 +1,172 @@
+import Foundation
+
+/// Errors from pass-snapshot, promote, and discovery operations.
+public enum MeasurementArtefactError: LocalizedError, Equatable, Sendable {
+    case invalidBasename(String)
+    case canonicalMissing(URL)
+    case snapshotFailed(String)
+    case promoteFailed(String)
+    case noPassFiles
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidBasename(let name):
+            return "Invalid measurement basename: \(name)"
+        case .canonicalMissing(let url):
+            return "Canonical .ti3 not found: \(url.path)"
+        case .snapshotFailed(let reason):
+            return "Snapshot failed: \(reason)"
+        case .promoteFailed(let reason):
+            return "Promote failed: \(reason)"
+        case .noPassFiles:
+            return "No pass .ti3 snapshots are available."
+        }
+    }
+}
+
+/// Filesystem helpers for multi-pass measurement artefacts.
+///
+/// Pass snapshots use 1-based numbering and are tracked as
+/// `<basename>_passN.ti3`. Canonical `<basename>.ti3` only appears after
+/// Finish / Average (docs/24 #109, #110).
+public enum MeasurementArtefacts {
+
+    /// Find all existing pass snapshots in `cwd`, sorted numerically.
+    public static func passSnapshots(
+        basename: String,
+        cwd: URL,
+        fileManager: FileManager = .default
+    ) -> [URL] {
+        guard let entries = try? fileManager.contentsOfDirectory(
+            at: cwd,
+            includingPropertiesForKeys: nil,
+            options: [.skipsHiddenFiles]
+        ) else { return [] }
+
+        let prefix = "\(basename)_pass"
+        let suffix = "ti3"
+
+        let passes: [(Int, URL)] = entries.compactMap { url in
+            let name = url.lastPathComponent
+            guard url.pathExtension.lowercased() == suffix,
+                  name.hasPrefix(prefix)
+            else { return nil }
+
+            let numberPart = String(name.dropFirst(prefix.count).dropLast(4))
+            guard let number = Int(numberPart), number > 0 else { return nil }
+            return (number, url)
+        }
+
+        return passes
+            .sorted { $0.0 < $1.0 }
+            .map { $0.1 }
+    }
+
+    /// The next 1-based pass number.
+    public static func nextPassNumber(
+        basename: String,
+        cwd: URL,
+        fileManager: FileManager = .default
+    ) -> Int {
+        let existing = passSnapshots(basename: basename, cwd: cwd, fileManager: fileManager)
+        guard let last = existing.last else { return 1 }
+        let name = last.lastPathComponent
+        let prefix = "\(basename)_pass"
+        let numberPart = String(name.dropFirst(prefix.count).dropLast(4))
+        return (Int(numberPart) ?? 0) + 1
+    }
+
+    /// Snapshot canonical `<basename>.ti3` to `<basename>_passN.ti3` and remove canonical.
+    ///
+    /// The copy is written to a temp sibling and atomically renamed before canonical is deleted.
+    public static func snapshotPass(
+        basename: String,
+        cwd: URL,
+        fileManager: FileManager = .default
+    ) throws -> URL {
+        let cleanBasename = try PathSecurity.sanitizeBasename(basename)
+        let canonical = cwd.appendingPathComponent("\(cleanBasename).ti3")
+        guard fileManager.fileExists(atPath: canonical.path) else {
+            throw MeasurementArtefactError.canonicalMissing(canonical)
+        }
+
+        let passNumber = nextPassNumber(basename: cleanBasename, cwd: cwd, fileManager: fileManager)
+        let pass = cwd.appendingPathComponent("\(cleanBasename)_pass\(passNumber).ti3")
+        let temp = cwd.appendingPathComponent(".\(cleanBasename)_pass\(passNumber).ti3.iccery-snap.tmp")
+
+        if fileManager.fileExists(atPath: temp.path) {
+            try? fileManager.removeItem(at: temp)
+        }
+
+        do {
+            try fileManager.copyItem(at: canonical, to: temp)
+        } catch {
+            throw MeasurementArtefactError.snapshotFailed(error.localizedDescription)
+        }
+
+        if fileManager.fileExists(atPath: pass.path) {
+            try? fileManager.removeItem(at: pass)
+        }
+
+        do {
+            try fileManager.moveItem(at: temp, to: pass)
+        } catch {
+            try? fileManager.removeItem(at: temp)
+            throw MeasurementArtefactError.snapshotFailed(error.localizedDescription)
+        }
+
+        do {
+            try fileManager.removeItem(at: canonical)
+        } catch {
+            // The pass file is durable; canonical removal failure is logged but not fatal.
+            throw MeasurementArtefactError.snapshotFailed(error.localizedDescription)
+        }
+
+        return pass
+    }
+
+    /// Promote a single pass snapshot to canonical `<basename>.ti3`.
+    public static func promotePass(
+        pass: URL,
+        basename: String,
+        cwd: URL,
+        fileManager: FileManager = .default
+    ) throws -> URL {
+        let cleanBasename = try PathSecurity.sanitizeBasename(basename)
+        let canonical = cwd.appendingPathComponent("\(cleanBasename).ti3")
+        let temp = cwd.appendingPathComponent(".\(cleanBasename).ti3.iccery-promo.tmp")
+
+        guard fileManager.fileExists(atPath: pass.path) else {
+            throw MeasurementArtefactError.noPassFiles
+        }
+
+        if fileManager.fileExists(atPath: temp.path) {
+            try? fileManager.removeItem(at: temp)
+        }
+
+        do {
+            try fileManager.copyItem(at: pass, to: temp)
+        } catch {
+            throw MeasurementArtefactError.promoteFailed(error.localizedDescription)
+        }
+
+        if fileManager.fileExists(atPath: canonical.path) {
+            try? fileManager.removeItem(at: canonical)
+        }
+
+        do {
+            try fileManager.moveItem(at: temp, to: canonical)
+        } catch {
+            try? fileManager.removeItem(at: temp)
+            throw MeasurementArtefactError.promoteFailed(error.localizedDescription)
+        }
+
+        return canonical
+    }
+
+    /// Canonical `<basename>.ti3` URL, regardless of existence.
+    public static func canonicalURL(basename: String, cwd: URL) throws -> URL {
+        let cleanBasename = try PathSecurity.sanitizeBasename(basename)
+        return cwd.appendingPathComponent("\(cleanBasename).ti3")
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Paths/AppPaths.swift

@@ -14,20 +14,41 @@ public enum AppPaths {
     }
 
     /// `~/Library/Application Support/com.gronod.iccery2`
+    ///
+    /// DEBUG only: `ICCERY_TEST_ROOT` redirects app data so UI tests run
+    /// against an isolated root and never touch the developer's state.
     public static var appDataDir: URL {
-        FileManager.default
+        #if DEBUG
+        if let root = testRoot {
+            return root.appendingPathComponent("AppData", isDirectory: true)
+        }
+        #endif
+        return FileManager.default
             .urls(for: .applicationSupportDirectory, in: .userDomainMask)[0]
             .appendingPathComponent(bundleIdentifier, isDirectory: true)
     }
 
     /// `~/Library/Logs/com.gronod.iccery2`
     public static var logDir: URL {
-        FileManager.default
+        #if DEBUG
+        if let root = testRoot {
+            return root.appendingPathComponent("Logs", isDirectory: true)
+        }
+        #endif
+        return FileManager.default
             .urls(for: .libraryDirectory, in: .userDomainMask)[0]
             .appendingPathComponent("Logs", isDirectory: true)
             .appendingPathComponent(bundleIdentifier, isDirectory: true)
     }
 
+    #if DEBUG
+    private static var testRoot: URL? {
+        guard let raw = ProcessInfo.processInfo.environment["ICCERY_TEST_ROOT"],
+              !raw.isEmpty else { return nil }
+        return URL(fileURLWithPath: raw, isDirectory: true)
+    }
+    #endif
+
     /// `~/Library/Logs/com.gronod.iccery2/iccery.log`
     public static var logFile: URL {
         logDir.appendingPathComponent("iccery.log", isDirectory: false)

Packages/ICCeryCore/Sources/ICCeryCore/Print/ColorMatchingAttempts.swift

@@ -0,0 +1,49 @@
+import Foundation
+
+/// Ordered private-SPI attempt table for the ColorSync suppression
+/// engine (issue 14 layer ②, docs/11).
+///
+/// The ordering is data so the exact dlsym/mode sequence is unit-
+/// testable without resolving any private symbols. The app layer walks
+/// `attempts`, resolves each symbol via `dlsym(RTLD_DEFAULT,…)`, and
+/// calls the first `(symbol, mode)` that returns `0` — verified on
+/// macOS 14+ that all three symbols exist.
+///
+/// The SPI signature is `(PMPrintSession, CFStringRef) -> OSStatus`.
+/// The second argument is the **mode string**, never integer `1`
+/// (#188 — a 3-arg call is a SIGSEGV). `AP_ColorSyncMatching` and
+/// `AP_VendorColorMatching` are forbidden modes — they re-enable
+/// ColorSync/driver colour management.
+public enum ColorMatchingAttempts {
+
+    /// dlsym order: `…Lock` first (holds the print-session lock while
+    /// setting), then the plain setter, then `…NoLock`.
+    public static let symbols: [String] = [
+        "PMSessionSetColorMatchingModeLock",
+        "PMSessionSetColorMatchingMode",
+        "PMSessionSetColorMatchingModeNoLock",
+    ]
+
+    /// Mode strings tried per symbol, in order. `AP_…` is the
+    /// documented mode; the unprefixed variant is the older alias.
+    public static let modes: [String] = [
+        "AP_ApplicationColorMatching",
+        "ApplicationColorMatching",
+    ]
+
+    /// Symbol-outer, mode-inner — the full attempt sequence; the app
+    /// stops at the first call that returns `0`.
+    public static var attempts: [(symbol: String, mode: String)] {
+        symbols.flatMap { symbol in
+            modes.map { (symbol: symbol, mode: $0) }
+        }
+    }
+
+    /// Layer ③: both spellings of the print-settings key are written
+    /// with `locked = true`. Written as `CFString` values.
+    public static let applicationMatchingValue = "AP_ApplicationColorMatching"
+    public static let printSettingsKeys: [String] = [
+        "AP_ColorMatchingMode",
+        "AP.ColorMatchingMode",
+    ]
+}

Packages/ICCeryCore/Sources/ICCeryCore/Print/CupsOptionsFilter.swift

@@ -0,0 +1,62 @@
+import Foundation
+
+/// CUPS option filtering for `PMPrintSettingsToOptions` capture
+/// (issue 14 layer ⑥, docs/11 §filter).
+///
+/// The captured `key=value` string is reduced to the options that
+/// should be replayed on `lp`: `com.apple.*` ticket keys, job
+/// bookkeeping (`collate`, `copies`, `pserrorhandler-requested`,
+/// `job-sheets`), empty values, and **both** `AP_*ColorMatchingMode`
+/// keys are dropped — `build_lp_args` always re-adds those itself
+/// (issue 15). Unknown non-`com.*` keys are kept (permissive — vendor
+/// driver keys survive).
+public enum CupsOptionsFilter {
+
+    /// Option keys forwarded from the panel to `lp` (docs/11 roster).
+    public static let relevantKeys: Set<String> = [
+        // Media
+        "MediaType", "CNIJMediaType", "EPIJ_Medi", "StpMediaType",
+        // Tray
+        "InputSlot", "AP_D_InputSlot",
+        // Size
+        "PageSize",
+        // Colour bypass
+        "CNIJIntent2", "CNIJIntent", "EPIJ_CMat", "EPIJ_CCor",
+        "EPIJ_OSColMat", "ColorCorrection", "StpColorCorrection",
+        "EpsonColorMode", "ColorModel",
+        // Quality
+        "Resolution", "cupsPrintQuality", "Quality", "EPIJ_Quality",
+        "CNIJQuality", "StpQuality", "OutputMode",
+        // Duplex
+        "Duplex", "sides",
+    ]
+
+    /// Keys we always drop regardless of the relevant list. `raw` is
+    /// included — a captured `raw=…` would re-enable CUPS raw mode and
+    /// bypass the raster filter that honours `AP_ApplicationColorMatching`
+    /// (#92).
+    public static let alwaysDropped: Set<String> = [
+        "collate", "copies", "pserrorhandler-requested", "job-sheets",
+        "AP_ColorMatchingMode", "AP.ColorMatchingMode", "raw",
+    ]
+
+    /// A `key=value` pair survives when the key is non-empty, the value
+    /// is non-empty, the key is not `com.apple.*`, not always-dropped,
+    /// and either relevant or an unknown non-`com.*` driver key.
+    public static func isRelevant(key: String, value: String) -> Bool {
+        guard !key.isEmpty, !value.isEmpty else { return false }
+        if key.hasPrefix("com.apple.") { return false }
+        if alwaysDropped.contains(key) { return false }
+        if relevantKeys.contains(key) { return true }
+        // Permissive: unknown vendor keys survive (non-com.*).
+        return !key.hasPrefix("com.")
+    }
+
+    /// `key=value key=value …` → filtered string, order preserved.
+    public static func filter(_ options: String) -> String {
+        CupsParsers.lpoptions(options)
+            .filter { isRelevant(key: $0.key, value: $0.value) }
+            .map { "\($0.key)=\($0.value)" }
+            .joined(separator: " ")
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Print/CupsParsers.swift

@@ -0,0 +1,264 @@
+import Foundation
+
+/// One `lpoptions -l` line: `Key/Human Label: *default choice choice`.
+public struct CupsOptionListing: Equatable, Sendable {
+    /// Machine key before `/`, e.g. `InputSlot` or `CNIJMediaType`.
+    public var key: String
+    /// Human label after `/`, e.g. `Media Source`.
+    public var label: String
+    /// All choices, `*` stripped.
+    public var choices: [String]
+    /// The `*`-prefixed default choice, if any.
+    public var defaultChoice: String?
+
+    public init(key: String, label: String, choices: [String], defaultChoice: String?) {
+        self.key = key
+        self.label = label
+        self.choices = choices
+        self.defaultChoice = defaultChoice
+    }
+}
+
+/// Pure parsers for `lpstat` / `lpoptions` / PPD text (issue 12,
+/// docs/10–11). Recorded fixtures drive the tests — no live CUPS.
+public enum CupsParsers {
+
+    // MARK: - lpstat
+
+    /// `lpstat -e` — one CUPS destination name per line.
+    public static func lpstatDestinations(_ output: String) -> [String] {
+        output.split(separator: "\n")
+            .map { $0.trimmingCharacters(in: .whitespaces) }
+            .filter { !$0.isEmpty }
+    }
+
+    /// `lpstat -p` — `printer NAME is idle. enabled since …`,
+    /// `printer NAME now printing NAME-1. …`, `printer NAME disabled
+    /// since …` → queue → status.
+    public static func lpstatStatuses(_ output: String) -> [String: PrinterStatus] {
+        var result: [String: PrinterStatus] = [:]
+        for line in output.split(separator: "\n") {
+            let text = line.trimmingCharacters(in: .whitespaces)
+            guard text.hasPrefix("printer ") else { continue }
+            let rest = text.dropFirst("printer ".count)
+            guard let sep = rest.firstIndex(of: " ") else { continue }
+            let name = String(rest[..<sep])
+            let desc = rest[sep...].lowercased()
+            if desc.contains("now printing") {
+                result[name] = .printing
+            } else if desc.contains("idle") {
+                result[name] = .idle
+            } else if desc.contains("disabled") || desc.contains("stopped") {
+                result[name] = .stopped
+            } else {
+                result[name] = .unknown
+            }
+        }
+        return result
+    }
+
+    /// `lpstat -d` — `system default destination: NAME`, or
+    /// `no system default destination` → nil.
+    public static func lpstatDefault(_ output: String) -> String? {
+        for line in output.split(separator: "\n") {
+            let text = line.trimmingCharacters(in: .whitespaces)
+            guard let colon = text.firstIndex(of: ":") else { continue }
+            let name = text[text.index(after: colon)...]
+                .trimmingCharacters(in: .whitespaces)
+            if text.lowercased().hasPrefix("system default destination"),
+               !name.isEmpty {
+                return name
+            }
+        }
+        return nil
+    }
+
+    // MARK: - lpoptions -p <queue>
+
+    /// `lpoptions -p` — `key=value` pairs, values may be
+    /// single-quoted (`printer-info='EPSON XP-55 Series'`); bare
+    /// flags (`printer-location`) parse as present-with-empty-value.
+    public static func lpoptions(_ output: String) -> [(key: String, value: String)] {
+        var pairs: [(String, String)] = []
+        var index = output.startIndex
+        while index < output.endIndex {
+            while index < output.endIndex && output[index].isWhitespace {
+                index = output.index(after: index)
+            }
+            guard index < output.endIndex else { break }
+            let tokenStart = index
+            while index < output.endIndex && output[index] != "=" && !output[index].isWhitespace {
+                index = output.index(after: index)
+            }
+            let key = String(output[tokenStart..<index])
+            // A token starting with `=` has no key — skip it (and its
+            // value) rather than truncating the whole parse.
+            guard !key.isEmpty else {
+                if index < output.endIndex && output[index] == "=" {
+                    index = output.index(after: index)
+                    while index < output.endIndex
+                            && !output[index].isWhitespace {
+                        index = output.index(after: index)
+                    }
+                }
+                continue
+            }
+            if index < output.endIndex && output[index] == "=" {
+                index = output.index(after: index)
+                if index < output.endIndex && output[index] == "'" {
+                    // Single-quoted value — scan to closing quote.
+                    index = output.index(after: index)
+                    let valueStart = index
+                    while index < output.endIndex && output[index] != "'" {
+                        index = output.index(after: index)
+                    }
+                    pairs.append((key, String(output[valueStart..<index])))
+                    if index < output.endIndex { index = output.index(after: index) }
+                } else {
+                    let valueStart = index
+                    while index < output.endIndex && !output[index].isWhitespace {
+                        index = output.index(after: index)
+                    }
+                    pairs.append((key, String(output[valueStart..<index])))
+                }
+            } else {
+                pairs.append((key, ""))
+            }
+        }
+        return pairs
+    }
+
+    /// Display name from `printer-info` in `lpoptions -p` output.
+    public static func lpoptionsDisplayName(_ output: String) -> String? {
+        guard let value = lpoptions(output)
+            .first(where: { $0.key == "printer-info" })?.value,
+            !value.isEmpty
+        else { return nil }
+        return value
+    }
+
+    // MARK: - lpoptions -l
+
+    /// `lpoptions -l` — `Key/Human Label: *Default choice2 choice3`.
+    /// A missing `/` label reuses the key.
+    public static func lpoptionsList(_ output: String) -> [CupsOptionListing] {
+        output.split(separator: "\n").compactMap { raw in
+            let line = raw.trimmingCharacters(in: .whitespaces)
+            guard let colon = line.firstIndex(of: ":") else { return nil }
+            let head = String(line[..<colon])
+            let body = line[line.index(after: colon)...]
+            let headParts = head.split(separator: "/", maxSplits: 1)
+            let key = headParts[0].trimmingCharacters(in: .whitespaces)
+            guard !key.isEmpty else { return nil }
+            let label = headParts.count > 1
+                ? headParts[1].trimmingCharacters(in: .whitespaces)
+                : key
+            var choices: [String] = []
+            var defaultChoice: String?
+            for token in body.split(separator: " ") {
+                if token.hasPrefix("*") {
+                    let value = String(token.dropFirst())
+                    defaultChoice = value
+                    choices.append(value)
+                } else {
+                    choices.append(String(token))
+                }
+            }
+            return CupsOptionListing(
+                key: key, label: label,
+                choices: choices, defaultChoice: defaultChoice)
+        }
+    }
+
+    // MARK: - PPD enrichment
+
+    /// PPD `*<key> <id>/<Human Label>:` lines → `id → label` map.
+    /// Language-qualified forms (`*en_US.<key> id/Label:`) also match.
+    public static func ppdChoiceLabels(_ ppd: String, key: String) -> [String: String] {
+        var map: [String: String] = [:]
+        for rawLine in ppd.split(separator: "\n") {
+            var line = rawLine.trimmingCharacters(in: .whitespaces)
+            guard line.hasPrefix("*"), !line.hasPrefix("**") else { continue }
+            line = String(line.dropFirst())
+            // Optional locale qualifier: `en_US.InputSlot` → `InputSlot`.
+            // Only strip when the part before the first `.` looks like
+            // a locale (short `xx`/`xx_YY`); real keys containing dots
+            // are left alone.
+            if let dot = line.firstIndex(of: ".") {
+                let prefix = line[..<dot]
+                let looksLikeLocale = (2...5).contains(prefix.count)
+                    && prefix.allSatisfy { $0.isLetter || $0 == "_" }
+                    && (prefix.count == 2 || prefix.contains("_"))
+                let candidate = line[line.index(after: dot)...]
+                if looksLikeLocale && candidate.hasPrefix(key) {
+                    line = String(candidate)
+                }
+            }
+            guard line.hasPrefix(key) else { continue }
+            var rest = line[line.index(line.startIndex, offsetBy: key.count)...]
+                .trimmingCharacters(in: .whitespaces)
+            guard let colon = rest.firstIndex(of: ":") else { continue }
+            rest = String(rest[..<colon])
+            // `<id>/<Human label>` — human label after the last `/`.
+            guard let slash = rest.firstIndex(of: "/") else { continue }
+            let id = String(rest[..<slash])
+                .trimmingCharacters(in: .whitespaces)
+            let human = String(rest[rest.index(after: slash)...])
+                .trimmingCharacters(in: .whitespaces)
+            if !id.isEmpty { map[id] = human.isEmpty ? id : human }
+        }
+        return map
+    }
+
+    // MARK: - Detection (docs/11)
+
+    /// Media-type option key in preference order — used both to read a
+    /// captured value and to emit `-o <key>=<media>`.
+    public static let mediaTypeKeys = [
+        "CNIJMediaType", "EPIJ_Medi", "StpMediaType", "MediaType"
+    ]
+
+    public static func detectMediaTypeKey(optionKeys: Set<String>) -> String? {
+        mediaTypeKeys.first { optionKeys.contains($0) }
+    }
+
+    /// Media type from a captured `key=value key=value` options string.
+    /// Prefers `MediaType`, then `EPIJ_Medi` (docs/11 §tests).
+    public static func extractMediaType(fromOptionsString options: String) -> String? {
+        let pairs = lpoptions(options)
+        if let v = pairs.first(where: { $0.key == "MediaType" })?.value {
+            return v
+        }
+        return pairs.first(where: { $0.key == "EPIJ_Medi" })?.value
+    }
+
+    /// Driver "no colour adjustment" key=value for `lpoptions -l` keys
+    /// (docs/11 layer ④): Canon `CNIJIntent2=4` else `CNIJIntent=4`;
+    /// Epson `EPIJ_CCor=0` when the key exists else `EPIJ_CMat=3`;
+    /// Gutenprint `StpColorCorrection=Uncorrected`; generic
+    /// `ColorCorrection=Uncorrected`; `EpsonColorMode=Off`.
+    public static func detectDriverColorBypass(
+        optionKeys: Set<String>
+    ) -> (key: String, value: String)? {
+        if optionKeys.contains("CNIJIntent2") { return ("CNIJIntent2", "4") }
+        if optionKeys.contains("CNIJIntent") { return ("CNIJIntent", "4") }
+        if optionKeys.contains("EPIJ_CCor") { return ("EPIJ_CCor", "0") }
+        if optionKeys.contains("EPIJ_CMat") { return ("EPIJ_CMat", "3") }
+        if optionKeys.contains("StpColorCorrection") {
+            return ("StpColorCorrection", "Uncorrected")
+        }
+        if optionKeys.contains("ColorCorrection") {
+            return ("ColorCorrection", "Uncorrected")
+        }
+        if optionKeys.contains("EpsonColorMode") { return ("EpsonColorMode", "Off") }
+        return nil
+    }
+
+    /// The key=value pairs of colour-bypass keys — used to detect
+    /// whether captured options already carry a bypass.
+    public static let bypassKeys: Set<String> = [
+        "CNIJIntent2", "CNIJIntent", "EPIJ_CMat", "EPIJ_CCor",
+        "EPIJ_OSColMat", "ColorCorrection", "StpColorCorrection",
+        "EpsonColorMode",
+    ]
+}

Packages/ICCeryCore/Sources/ICCeryCore/Print/CupsService.swift

@@ -0,0 +1,191 @@
+import Foundation
+
+/// Errors from CUPS tool invocations.
+public enum CupsError: LocalizedError, Equatable {
+    case toolFailed(tool: String, code: Int32, stderr: String)
+    case tiffMissing(String)
+    case noPrinterSelected
+
+    public var errorDescription: String? {
+        switch self {
+        case .toolFailed(let tool, let code, let stderr):
+            let detail = stderr.trimmingCharacters(in: .whitespacesAndNewlines)
+            return detail.isEmpty
+                ? "\(tool) failed with exit code \(code)"
+                : "\(tool) failed (\(code)): \(detail)"
+        case .tiffMissing(let path):
+            return "Target TIFF does not exist: \(path)"
+        case .noPrinterSelected:
+            return "No printer selected."
+        }
+    }
+}
+
+/// CUPS command surface (issue 12): enumerates queues and reads
+/// per-queue capabilities via `/usr/bin/lpstat` and
+/// `/usr/bin/lpoptions`. Spawning goes through
+/// `ProcessManager.runCaptured` so spawns are logged, get killAll
+/// coverage, and share the dup-id discipline; `binaryDir`/`ppdDir` are
+/// injectable so tests use fixture scripts and never touch real CUPS.
+public struct CupsService: Sendable {
+    public let processManager: ProcessManager
+    /// Directory containing `lpstat`/`lpoptions`/`lp` — `/usr/bin` in
+    /// production, a fixture dir under test.
+    public let binaryDir: URL
+    /// `/etc/cups/ppd` in production.
+    public let ppdDir: URL
+
+    public init(
+        processManager: ProcessManager = .shared,
+        binaryDir: URL = URL(fileURLWithPath: "/usr/bin"),
+        ppdDir: URL = URL(fileURLWithPath: "/etc/cups/ppd")
+    ) {
+        self.processManager = processManager
+        self.binaryDir = binaryDir
+        self.ppdDir = ppdDir
+    }
+
+    // MARK: - Enumeration (lpstat -e/-p/-d)
+
+    /// All CUPS destinations with status and default flag. An empty
+    /// list is a valid result, not an error.
+    public func listPrinters() async throws -> [Printer] {
+        // lpstat exits non-zero when no destinations exist — an empty
+        // queue list is a valid result, not a failure (issue 12).
+        let destinationsOut = try await run(
+            "lpstat", ["-e"], id: ProcessID.lpstat("e"), tolerateFailure: true)
+        let statusOut = try await run(
+            "lpstat", ["-p"], id: ProcessID.lpstat("p"), tolerateFailure: true)
+        let defaultOut = try await run(
+            "lpstat", ["-d"], id: ProcessID.lpstat("d"), tolerateFailure: true)
+
+        let names = CupsParsers.lpstatDestinations(destinationsOut.stdout)
+        let statuses = CupsParsers.lpstatStatuses(statusOut.stdout)
+        let defaultName = CupsParsers.lpstatDefault(defaultOut.stdout)
+
+        var printers: [Printer] = []
+        for name in names {
+            let displayName = try? await displayName(for: name)
+            printers.append(Printer(
+                name: name,
+                status: statuses[name] ?? .unknown,
+                isDefault: name == defaultName,
+                displayName: displayName
+            ))
+        }
+        return printers
+    }
+
+    /// `lpoptions -p <queue>` → `printer-info` (the NSPrinter fallback
+    /// display name, docs/11 §binding).
+    public func displayName(for queue: String) async throws -> String? {
+        let result = try await run(
+            "lpoptions", ["-p", queue], id: ProcessID.lpoptions(queue))
+        return CupsParsers.lpoptionsDisplayName(result.stdout)
+    }
+
+    // MARK: - Capabilities (lpoptions -l + PPD)
+
+    /// Raw `Key/Label: choices` listings for a queue — also the input
+    /// to media-key and colour-bypass detection (docs/11 layer ④).
+    public func optionListings(for queue: String) async throws -> [CupsOptionListing] {
+        let result = try await run(
+            "lpoptions", ["-p", queue, "-l"], id: ProcessID.lpoptions("\(queue)-l"))
+        return CupsParsers.lpoptionsList(result.stdout)
+    }
+
+    /// Trays / paper sizes / media types for a queue, with PPD
+    /// `*Key id/Human:` enrichment when the queue's PPD is readable.
+    public func capabilities(for queue: String) async throws -> PrinterCapabilities {
+        let listings = try await optionListings(for: queue)
+        return capabilities(from: listings, ppd: loadPPD(for: queue))
+    }
+
+    /// Pure mapping — extracted so fixture tests need no process.
+    public func capabilities(
+        from listings: [CupsOptionListing],
+        ppd: String?
+    ) -> PrinterCapabilities {
+        var trays: [PrinterTray] = []
+        var sizes: [PrinterPaperSize] = []
+        var media: [PrinterMediaType] = []
+
+        for listing in listings {
+            switch listing.key {
+            case "InputSlot", "MediaSource":
+                trays = listing.choices.enumerated().map {
+                    PrinterTray(id: $0.offset + 1, name: $0.element)
+                }
+            case "PageSize", "MediaSize":
+                sizes = listing.choices.enumerated().map {
+                    PrinterPaperSize(id: $0.offset + 1, name: $0.element)
+                }
+            case let key where CupsParsers.mediaTypeKeys.contains(key):
+                guard media.isEmpty else { continue }
+                let labels = ppd.map {
+                    CupsParsers.ppdChoiceLabels($0, key: key)
+                } ?? [:]
+                media = listing.choices.map {
+                    PrinterMediaType(id: $0, name: labels[$0] ?? $0)
+                }
+            default:
+                continue
+            }
+        }
+        return PrinterCapabilities(
+            trays: trays, paperSizes: sizes, mediaTypes: media)
+    }
+
+    /// The set of option keys a queue advertises — input to
+    /// `detectDriverColorBypass` / `detectMediaTypeKey`.
+    public func optionKeys(for queue: String) async throws -> Set<String> {
+        Set(try await optionListings(for: queue).map(\.key))
+    }
+
+    // MARK: - Spool (issue 15)
+
+    /// `lp -d <queue> … <tiff>` — spool one target page unmanaged.
+    /// Never uses `-o raw` (#92). `page` disambiguates the process id
+    /// when several pages are spooled in sequence.
+    public func printTarget(
+        queue: String,
+        tiffPath: String,
+        options: PrintOptions,
+        page: Int = 0
+    ) async throws {
+        guard FileManager.default.fileExists(atPath: tiffPath) else {
+            throw CupsError.tiffMissing(tiffPath)
+        }
+        let optionKeys = (try? await self.optionKeys(for: queue)) ?? []
+        let argv = try LpArgs.build(
+            queue: queue, tiffPath: tiffPath,
+            options: options, optionKeys: optionKeys)
+        try await run("lp", argv, id: ProcessID.lp(queue, page: page))
+    }
+
+    // MARK: - PPD
+
+    private func loadPPD(for queue: String) -> String? {
+        let url = ppdDir.appendingPathComponent("\(queue).ppd")
+        return try? String(contentsOf: url, encoding: .utf8)
+    }
+
+    // MARK: - Spawn
+
+    @discardableResult
+    func run(
+        _ tool: String,
+        _ arguments: [String],
+        id: String,
+        tolerateFailure: Bool = false
+    ) async throws -> CapturedResult {
+        let binary = binaryDir.appendingPathComponent(tool)
+        let result = try await processManager.runCaptured(
+            id: id, binary: binary, arguments: arguments)
+        if result.exitCode != 0, !tolerateFailure {
+            throw CupsError.toolFailed(
+                tool: tool, code: result.exitCode, stderr: result.stderr)
+        }
+        return result
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Print/LpArgs.swift

@@ -0,0 +1,126 @@
+import Foundation
+
+/// Errors from `buildLpArgs`.
+public enum LpArgsError: LocalizedError, Equatable {
+    case unsanitisedOption(String)
+
+    public var errorDescription: String? {
+        switch self {
+        case .unsanitisedOption(let option):
+            return "Captured CUPS option contains unsafe characters: \(option)"
+        }
+    }
+}
+
+/// `lp` argv builder — issue 15, docs/11 `build_lp_args`.
+///
+/// ```
+/// lp -d <queue> -t "ICCery Target - <file>"
+///    -o AP_ColorMatchingMode=AP_ApplicationColorMatching
+///    -o AP.ColorMatchingMode=AP_ApplicationColorMatching
+///    <captured cups_options>
+///    <media_type, if no media key already captured>
+///    <driver bypass, if no bypass key captured>
+///    <orientation-requested=3|4, unless captured>
+///    <PageSize, unless captured>
+///    <tiff>
+/// ```
+///
+/// - **Never `-o raw`** — `raw` skips the raster filter that honours
+///   `AP_ApplicationColorMatching` (#92).
+/// - Captured options **win** over explicit fields: any key already
+///   present (case-insensitive) suppresses the derived `-o`.
+/// - Captured keys/values are sanitised — `;`, newlines, or shell
+///   metacharacters throw `unsanitisedOption`; args are passed as a
+///   `Process` argv array, never through a shell.
+/// - The TIFF path is always the **last** argument.
+public enum LpArgs {
+
+    /// `options` = the captured `PrintOptions`; `optionKeys` = the
+    /// queue's `lpoptions -l` key set (for media-key/bypass detection).
+    public static func build(
+        queue: String,
+        tiffPath: String,
+        options: PrintOptions,
+        optionKeys: Set<String>
+    ) throws -> [String] {
+        var argv: [String] = [
+            "-d", queue,
+            "-t", "ICCery Target - \((tiffPath as NSString).lastPathComponent)",
+            "-o", "AP_ColorMatchingMode=AP_ApplicationColorMatching",
+            "-o", "AP.ColorMatchingMode=AP_ApplicationColorMatching",
+        ]
+        var addedKeys: Set<String> = [
+            "ap_colormatchingmode", "ap.colormatchingmode",
+        ]
+
+        // Captured CUPS options — sanitised, lowercased-key dedup.
+        if let captured = options.cupsOptions, !captured.isEmpty {
+            // Newlines can't survive the tokeniser — check the raw
+            // string so embedded line breaks are still rejected.
+            if captured.contains("\n") || captured.contains("\r") {
+                throw LpArgsError.unsanitisedOption(captured)
+            }
+            for pair in CupsParsers.lpoptions(captured) {
+                try sanitize(pair.key, pair.value)
+                let lowered = pair.key.lowercased()
+                // Defence in depth: never let a captured `raw` reach
+                // argv — `-o raw` skips the raster filter that honours
+                // AP_ApplicationColorMatching (#92).
+                if lowered == "raw" { continue }
+                guard !addedKeys.contains(lowered) else { continue }
+                addedKeys.insert(lowered)
+                argv += ["-o", "\(pair.key)=\(pair.value)"]
+            }
+        }
+
+        // Media type — only when the captured options didn't carry one.
+        if let mediaType = options.mediaType,
+           let mediaKey = CupsParsers.detectMediaTypeKey(optionKeys: optionKeys),
+           !addedKeys.contains(mediaKey.lowercased()) {
+            addedKeys.insert(mediaKey.lowercased())
+            argv += ["-o", "\(mediaKey)=\(mediaType)"]
+        }
+
+        // Driver colour bypass — when no bypass key was captured. NOT
+        // gated on ppdUncorrectedPassthrough (macOS always bypasses).
+        let capturedKeys = Set(
+            CupsParsers.lpoptions(options.cupsOptions ?? "")
+                .map { $0.key })
+        if capturedKeys.isDisjoint(with: CupsParsers.bypassKeys),
+           let bypass = CupsParsers.detectDriverColorBypass(optionKeys: optionKeys),
+           !addedKeys.contains(bypass.key.lowercased()) {
+            addedKeys.insert(bypass.key.lowercased())
+            argv += ["-o", "\(bypass.key)=\(bypass.value)"]
+        }
+
+        // Orientation — portrait=3, landscape=4.
+        if let orientation = options.orientation,
+           !addedKeys.contains("orientation-requested") {
+            let value = orientation == "landscape" ? "4" : "3"
+            addedKeys.insert("orientation-requested")
+            argv += ["-o", "orientation-requested=\(value)"]
+        }
+
+        // PageSize — the printtarg layout page size.
+        if let paperSize = options.paperSize, !paperSize.isEmpty,
+           !addedKeys.contains("pagesize") {
+            argv += ["-o", "PageSize=\(paperSize)"]
+        }
+
+        argv.append(tiffPath)
+        return argv
+    }
+
+    /// Reject shell/metachar injection — args go to `Process` as an
+    /// argv array, but a hostile captured string must not smuggle a
+    /// second option or command.
+    static func sanitize(_ key: String, _ value: String) throws {
+        let forbidden = CharacterSet(charactersIn: ";\n\r`|$&<>\\\"'")
+        if key.rangeOfCharacter(from: forbidden) != nil
+            || value.rangeOfCharacter(from: forbidden) != nil
+            || key.isEmpty {
+            throw LpArgsError.unsanitisedOption("\(key)=\(value)")
+        }
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Print/PrinterModels.swift

@@ -0,0 +1,136 @@
+import Foundation
+
+/// Queue status reported by `lpstat -p` (docs/10 §Printer).
+public enum PrinterStatus: String, Codable, Sendable, CaseIterable {
+    case idle = "Idle"
+    case printing = "Printing"
+    case stopped = "Stopped"
+    case unknown = "Unknown"
+}
+
+/// A CUPS destination. `name` is the queue id sent back to every
+/// subsequent print command; `displayName` is the human label from
+/// `printer-info` (used as the `NSPrinter` fallback when PM binding
+/// fails — #188).
+public struct Printer: Codable, Equatable, Sendable {
+    public var name: String
+    public var status: PrinterStatus
+    public var isDefault: Bool
+    public var displayName: String?
+
+    public init(
+        name: String,
+        status: PrinterStatus = .unknown,
+        isDefault: Bool = false,
+        displayName: String? = nil
+    ) {
+        self.name = name
+        self.status = status
+        self.isDefault = isDefault
+        self.displayName = displayName
+    }
+}
+
+/// Paper source. `id` is the 1-based index of the `InputSlot` /
+/// `MediaSource` choice (not a PPD code) — docs/10.
+public struct PrinterTray: Codable, Equatable, Sendable {
+    public var id: Int
+    public var name: String
+
+    public init(id: Int, name: String) {
+        self.id = id
+        self.name = name
+    }
+}
+
+/// Media size from `PageSize` / `MediaSize` choices (1-based index).
+public struct PrinterPaperSize: Codable, Equatable, Sendable {
+    public var id: Int
+    public var name: String
+
+    public init(id: Int, name: String) {
+        self.id = id
+        self.name = name
+    }
+}
+
+/// Media type: `id` is the PPD machine token, `name` the human label
+/// after `/` when a readable PPD enriches it (docs/10 §PPD id/Human).
+public struct PrinterMediaType: Codable, Equatable, Sendable {
+    public var id: String
+    public var name: String
+
+    public init(id: String, name: String) {
+        self.id = id
+        self.name = name
+    }
+}
+
+public struct PrinterCapabilities: Codable, Equatable, Sendable {
+    public var trays: [PrinterTray]
+    public var paperSizes: [PrinterPaperSize]
+    public var mediaTypes: [PrinterMediaType]
+    /// Always `true` on macOS (spec parity — CUPS honours
+    /// `orientation-requested`).
+    public var supportsOrientation: Bool
+
+    public init(
+        trays: [PrinterTray] = [],
+        paperSizes: [PrinterPaperSize] = [],
+        mediaTypes: [PrinterMediaType] = [],
+        supportsOrientation: Bool = true
+    ) {
+        self.trays = trays
+        self.paperSizes = paperSizes
+        self.mediaTypes = mediaTypes
+        self.supportsOrientation = supportsOrientation
+    }
+}
+
+/// Options carried into `lp` (docs/10 §PrintOptions). On macOS
+/// `paperSource` is ignored unless already present inside captured
+/// `cupsOptions`; `ppdUncorrectedPassthrough` is stored (the panel sets
+/// it on OK) but never gates the argv — macOS always bypasses driver
+/// colour management.
+public struct PrintOptions: Codable, Equatable, Sendable {
+    public var paperSource: Int?
+    /// `"portrait"` / `"landscape"` → `orientation-requested=3|4`.
+    public var orientation: String?
+    /// printtarg layout page size → `PageSize=` (skipped if captured).
+    public var paperSize: String?
+    public var mediaType: String?
+    public var ppdUncorrectedPassthrough: Bool?
+    /// Space-separated `key=value` captured from
+    /// `PMPrintSettingsToOptions` and filtered (docs/11 layer ⑥).
+    public var cupsOptions: String?
+
+    public init(
+        paperSource: Int? = nil,
+        orientation: String? = nil,
+        paperSize: String? = nil,
+        mediaType: String? = nil,
+        ppdUncorrectedPassthrough: Bool? = nil,
+        cupsOptions: String? = nil
+    ) {
+        self.paperSource = paperSource
+        self.orientation = orientation
+        self.paperSize = paperSize
+        self.mediaType = mediaType
+        self.ppdUncorrectedPassthrough = ppdUncorrectedPassthrough
+        self.cupsOptions = cupsOptions
+    }
+}
+
+/// Returned by the printer-properties panel (docs/10 §PrintPropertiesResult).
+/// `nil` from the service means the user cancelled — never an error.
+public struct PrintPropertiesResult: Codable, Equatable, Sendable {
+    /// CUPS printer id the panel ended on (`PMPrinterGetID`), or `nil`
+    /// when the `NSPrinter` fallback ran.
+    public var selectedPrinter: String?
+    public var options: PrintOptions
+
+    public init(selectedPrinter: String?, options: PrintOptions) {
+        self.selectedPrinter = selectedPrinter
+        self.options = options
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Process/JSONAccumulator.swift

@@ -0,0 +1,59 @@
+import Foundation
+
+/// Accumulates stdout lines into a complete JSON document.
+///
+/// Several Argyll tools (`instlist`, `profcheck`, `printtarg` manifest)
+/// emit pretty-printed multi-line JSON on stdout. Individual lines are
+/// *not* valid JSON — only the whole block is — so callers route stdout
+/// lines here and get `Data` back once the buffer parses.
+///
+/// `ROW_COLORS_JSON: ` lines never reach this type; ProcessManager
+/// diverts them to `jsonRow` events first.
+public struct JSONAccumulator: Sendable {
+    private var buffer = Data()
+
+    public init() {}
+
+    /// Appends one stdout line. Returns the complete document bytes when
+    /// the accumulated buffer forms valid JSON, otherwise `nil`.
+    public mutating func feed(line: String) -> Data? {
+        buffer.append(Data(line.utf8))
+        buffer.append(0x0A)
+        return tryParse()
+    }
+
+    /// Attempts to decode the accumulated buffer; clears it on success.
+    public mutating func decode<T: Decodable>(_ type: T.Type) -> T? {
+        guard let data = tryParse() else { return nil }
+        return try? JSONDecoder().decode(T.self, from: data)
+    }
+
+    /// Raw buffer when it parses, `nil` while still incomplete.
+    public var completeData: Data? {
+        var copy = self
+        return copy.tryParse()
+    }
+
+    public mutating func reset() {
+        buffer.removeAll(keepingCapacity: false)
+    }
+
+    public var isEmpty: Bool { buffer.isEmpty }
+
+    private mutating func tryParse() -> Data? {
+        // Cheap gate: JSON documents start with { or [.
+        guard let first = buffer.first(where: { !$0.isJSONWhitespace }),
+              first == UInt8(ascii: "{") || first == UInt8(ascii: "[")
+        else { return nil }
+        guard (try? JSONSerialization.jsonObject(with: buffer)) != nil else { return nil }
+        let out = buffer
+        buffer.removeAll(keepingCapacity: false)
+        return out
+    }
+}
+
+private extension UInt8 {
+    var isJSONWhitespace: Bool {
+        self == 0x20 || self == 0x09 || self == 0x0A || self == 0x0D
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Process/ProcessEvent.swift

@@ -0,0 +1,51 @@
+import Foundation
+
+/// Events on the process bus — the v2 equivalent of the v1 Tauri events
+/// `process:stdout|stderr|exit|error|json_row` (docs/02 §Event bus).
+public enum ProcessEvent: Sendable, Equatable {
+    /// Non-JSON stdout line. (`process:stdout`)
+    case stdout(id: String, line: String)
+    /// stderr line. (`process:stderr`)
+    case stderr(id: String, line: String)
+    /// Child exited; 0 = success. (`process:exit`)
+    case exit(id: String, code: Int32)
+    /// Spawn failure. (`process:error`)
+    case error(id: String, message: String)
+    /// Stdout line began with `ROW_COLORS_JSON: ` — prefix stripped,
+    /// payload is the remaining raw bytes. (`process:json_row`)
+    case jsonRow(id: String, payload: Data)
+
+    public var id: String {
+        switch self {
+        case .stdout(let id, _), .stderr(let id, _), .exit(let id, _),
+             .error(let id, _), .jsonRow(let id, _):
+            return id
+        }
+    }
+}
+
+public enum ProcessError: Error, Equatable, Sendable {
+    /// A child with this id is still running (#116).
+    case duplicateID(String)
+    /// No child registered under this id.
+    case unknownID(String)
+    /// Process refused to launch.
+    case spawnFailed(String)
+    /// stdin write failed (pipe closed / process gone).
+    case stdinFailed(String)
+}
+
+extension ProcessError: LocalizedError {
+    public var errorDescription: String? {
+        switch self {
+        case .duplicateID(let id):
+            return "Process already running: \(id)"
+        case .unknownID(let id):
+            return "Unknown process: \(id)"
+        case .spawnFailed(let detail):
+            return "Could not launch \(detail)"
+        case .stdinFailed(let detail):
+            return "stdin failed: \(detail)"
+        }
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Process/ProcessID.swift

@@ -0,0 +1,23 @@
+import Foundation
+
+/// Deterministic process ids (docs/02 §Event bus). Listeners must always
+/// filter events on `id` — historical bug #56 was an id mismatch.
+public enum ProcessID {
+    public static let instlist = "instlist"
+
+    public static func targen(_ basename: String) -> String { "targen_\(basename)" }
+    public static func printtarg(_ basename: String) -> String { "printtarg_\(basename)" }
+    public static func chartread(_ basename: String) -> String { "chartread_\(basename)" }
+    public static func average(_ basename: String) -> String { "average_\(basename)" }
+    public static func colprof(_ basename: String) -> String { "colprof_\(basename)" }
+    public static func profcheck(ti3Path: String) -> String { "profcheck_\(ti3Path)" }
+    public static func iccgamut(stem: String) -> String { "iccgamut_\(stem)" }
+    public static func printcal(_ stem: String) -> String { "printcal_\(stem)" }
+    public static func applycal(_ stem: String) -> String { "applycal_\(stem)" }
+
+    /// CUPS system tools (`/usr/bin/…`) — captured one-shots, not
+    /// streaming Argyll children.
+    public static func lpstat(_ mode: String) -> String { "lpstat_\(mode)" }
+    public static func lpoptions(_ queue: String) -> String { "lpoptions_\(queue)" }
+    public static func lp(_ queue: String, page: Int) -> String { "lp_\(queue)_\(page)" }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Process/ProcessLineDecoder.swift

@@ -0,0 +1,53 @@
+import Foundation
+
+/// Incremental byte→line decoder for process pipes.
+///
+/// Splits raw `availableData` chunks at `0x0A`. A newline byte can never
+/// appear inside a multi-byte UTF-8 sequence (continuation bytes are
+/// ≥ 0x80), so splitting bytes at `\n` is always scalar-safe; each line
+/// is then decoded with a lossy fallback for non-UTF-8 output.
+public struct ProcessLineDecoder: Sendable {
+    public private(set) var pending = Data()
+
+    public init() {}
+
+    /// Feeds a chunk; returns every complete line found (without `\n`).
+    public mutating func feed(_ chunk: Data) -> [String] {
+        guard !chunk.isEmpty else { return [] }
+        pending.append(chunk)
+        var lines: [String] = []
+        while let nl = pending.firstIndex(of: 0x0A) {
+            var slice = pending.prefix(upTo: nl)
+            pending = pending.suffix(from: pending.index(after: nl))
+            // Tolerate CRLF output.
+            if slice.last == 0x0D { slice = slice.dropLast() }
+            lines.append(Self.decode(slice))
+        }
+        return lines
+    }
+
+    /// Flushes any unterminated remainder at EOF. Returns `nil` when empty.
+    public mutating func finish() -> String? {
+        guard !pending.isEmpty else { return nil }
+        var rest = pending
+        pending.removeAll(keepingCapacity: false)
+        if rest.last == 0x0D { rest = rest.dropLast() }
+        return rest.isEmpty ? nil : Self.decode(rest)
+    }
+
+    /// Emits the current unterminated tail as a single line and clears it.
+    /// Used by `ProcessManager.flushPartialLine` for tools that emit
+    /// progress dots without newlines.
+    public mutating func flushPartial() -> String? {
+        guard !pending.isEmpty else { return nil }
+        var rest = pending
+        pending.removeAll(keepingCapacity: false)
+        if rest.last == 0x0D { rest = rest.dropLast() }
+        let text = Self.decode(rest)
+        return text.isEmpty ? nil : text
+    }
+
+    private static func decode(_ bytes: Data.SubSequence) -> String {
+        String(decoding: bytes, as: UTF8.self)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Process/ProcessManager.swift

@@ -0,0 +1,543 @@
+import Foundation
+
+/// Captured output from `runCaptured` — one-shot tools whose results
+/// arrive as buffered stdout/stderr (printcal/applycal, CUPS tools).
+public struct CapturedResult: Sendable, Equatable {
+    public let stdout: String
+    public let stderr: String
+    public let exitCode: Int32
+}
+
+/// Spawn / stdin / kill / event bus for Argyll sidecar children
+/// (docs/02 §Event bus, docs/03 §Process manager).
+///
+/// Invariants:
+/// - Duplicate `id` while a child runs is rejected (#116).
+/// - The stdin handle lives in its own map, independent of wait, so
+///   `sendStdin` never blocks on process exit (#84).
+/// - `ARGYLL_NOT_INTERACTIVE=1` is set on every child.
+/// - stdout lines beginning `ROW_COLORS_JSON: ` become `jsonRow` events
+///   with the prefix stripped; all other stdout is `stdout` events.
+/// - `exit` is emitted exactly once per child, and only after both
+///   output pipes reach EOF — so no buffered output is lost on fast
+///   exits or kills.  If EOFs never arrive, a watchdog finalizes.
+/// - `kill` runs a pre-kill hook (e.g. XY `q\n` + 500 ms park) before
+///   terminating.  Hooks are removed once the child finalizes.
+/// - `killAll` on `NSApplication.willTerminate` and last-window close
+///   runs all hooks and terminates every child (#147, #149).
+public actor ProcessManager {
+
+    public static let rowColorsPrefix = "ROW_COLORS_JSON: "
+
+    public static let shared = ProcessManager()
+
+    // MARK: - Event bus (multicast)
+
+    /// Lock-protected subscriber table. Registration is *synchronous*
+    /// inside `events()` so a caller can subscribe, then spawn, without
+    /// racing the child's first output or exit event.
+    private final class SubscriberBox: @unchecked Sendable {
+        private let lock = NSLock()
+        private var map: [UUID: AsyncStream<ProcessEvent>.Continuation] = [:]
+
+        func add(_ continuation: AsyncStream<ProcessEvent>.Continuation, token: UUID) {
+            lock.lock()
+            map[token] = continuation
+            lock.unlock()
+        }
+
+        func remove(_ token: UUID) {
+            lock.lock()
+            map.removeValue(forKey: token)
+            lock.unlock()
+        }
+
+        func yield(_ event: ProcessEvent) {
+            lock.lock()
+            let continuations = Array(map.values)
+            lock.unlock()
+            for continuation in continuations {
+                continuation.yield(event)
+            }
+        }
+    }
+
+    private nonisolated let subscriberBox = SubscriberBox()
+
+    /// Subscribe to the event bus. Each call returns an independent
+    /// stream; every event is delivered to every live subscriber.
+    /// The subscriber is registered before `events()` returns — callers
+    /// may spawn immediately after subscribing without losing events.
+    public nonisolated func events() -> AsyncStream<ProcessEvent> {
+        let box = subscriberBox
+        let token = UUID()
+        return AsyncStream { continuation in
+            box.add(continuation, token: token)
+            continuation.onTermination = { _ in box.remove(token) }
+        }
+    }
+
+    private nonisolated func emit(_ event: ProcessEvent) {
+        subscriberBox.yield(event)
+    }
+
+    // MARK: - Child registry
+
+    private struct RunningChild {
+        let process: Process
+        /// stdin lives in its own slot, independent of process wait (#84).
+        var stdin: FileHandle?
+        var stdoutDecoder: ProcessLineDecoder
+        var stderrDecoder: ProcessLineDecoder
+        var stdoutEOF = false
+        var stderrEOF = false
+        /// Set by the termination handler; `exit` is emitted once both
+        /// pipes have also reached EOF.
+        var pendingExitCode: Int32?
+        var finalized = false
+        /// Watchdog that forces finalization if EOFs never arrive.
+        var finalizeTask: Task<Void, Never>?
+    }
+
+    private var children: [String: RunningChild] = [:]
+    /// Processes owned by `runCaptured` (dup detection + kill support).
+    private var captured: [String: Process] = [:]
+
+    /// Hooks run by `kill` before terminating the child.
+    /// Used by `chartread` to park an XY head with `q\n`.
+    private var preKillHooks: [String: @Sendable () async -> Void] = [:]
+
+    /// Ids of currently-running children.
+    public var runningIDs: [String] { Array(children.keys) + captured.keys }
+
+    public func isRunning(_ id: String) -> Bool {
+        children[id] != nil || captured[id] != nil
+    }
+
+    // MARK: - Pre-kill hooks
+
+    /// Register a hook to run before `kill(id:)` terminates the child.
+    /// The hook is removed once the child finalizes.
+    public func setPreKillHook(id: String, hook: @escaping @Sendable () async -> Void) {
+        preKillHooks[id] = hook
+    }
+
+    // MARK: - Spawn (streaming)
+
+    /// Spawns a streaming child. Returns after spawn; callers wait for
+    /// `exit(id:)` events — never assume the return means the tool
+    /// finished (docs/03).
+    public func runStreaming(
+        id: String,
+        binary: URL,
+        arguments: [String],
+        workingDirectory: URL? = nil,
+        environment: [String: String] = [:]
+    ) throws {
+        guard !isRunning(id) else { throw ProcessError.duplicateID(id) }
+
+        let process = Process()
+        let stdinPipe = Pipe()
+        let stdoutPipe = Pipe()
+        let stderrPipe = Pipe()
+        process.executableURL = binary
+        process.arguments = arguments
+        process.currentDirectoryURL = workingDirectory
+        process.standardInput = stdinPipe
+        process.standardOutput = stdoutPipe
+        process.standardError = stderrPipe
+        process.environment = childEnvironment(extra: environment)
+
+        AppLogger(category: "process").debug(
+            "spawn \(id): \(binary.path) \(LogSanitizer.sanitizeArgs(arguments))"
+        )
+
+        children[id] = RunningChild(
+            process: process,
+            stdin: stdinPipe.fileHandleForWriting,
+            stdoutDecoder: ProcessLineDecoder(),
+            stderrDecoder: ProcessLineDecoder()
+        )
+
+        let stdoutHandle = stdoutPipe.fileHandleForReading
+        let stderrHandle = stderrPipe.fileHandleForReading
+        stdoutHandle.readabilityHandler = { [weak self] handle in
+            let data = handle.availableData
+            guard let self else { return }
+            Task { await self.ingestOutput(data, id: id, isStderr: false, handle: handle) }
+        }
+        stderrHandle.readabilityHandler = { [weak self] handle in
+            let data = handle.availableData
+            guard let self else { return }
+            Task { await self.ingestOutput(data, id: id, isStderr: true, handle: handle) }
+        }
+
+        process.terminationHandler = { [weak self] proc in
+            guard let self else { return }
+            Task { await self.didTerminate(id: id, code: proc.terminationStatus) }
+        }
+
+        do {
+            try process.run()
+        } catch {
+            preKillHooks.removeValue(forKey: id)
+            children.removeValue(forKey: id)
+            emit(.error(id: id, message: error.localizedDescription))
+            throw ProcessError.spawnFailed("\(binary.path): \(error.localizedDescription)")
+        }
+    }
+
+    // MARK: - Spawn (captured)
+
+    /// Runs a child to completion and returns all output. Reads stdout
+    /// and stderr concurrently so a full pipe buffer can never deadlock
+    /// the child. Used by `printcal` / `applycal` (docs/03) and by
+    /// `CupsService` for `/usr/bin/lpstat`, `lpoptions`, `lp` (#12/#15).
+    public func runCaptured(
+        id: String,
+        binary: URL,
+        arguments: [String],
+        workingDirectory: URL? = nil,
+        environment: [String: String] = [:]
+    ) async throws -> CapturedResult {
+        guard !isRunning(id) else { throw ProcessError.duplicateID(id) }
+
+        let process = Process()
+        let stdoutPipe = Pipe()
+        let stderrPipe = Pipe()
+        process.executableURL = binary
+        process.arguments = arguments
+        process.currentDirectoryURL = workingDirectory
+        process.standardOutput = stdoutPipe
+        process.standardError = stderrPipe
+        process.environment = childEnvironment(extra: environment)
+
+        AppLogger(category: "process").debug(
+            "spawn(captured) \(id): \(binary.path) \(LogSanitizer.sanitizeArgs(arguments))"
+        )
+
+        // Register and set up the termination hand-off before run() so
+        // a very fast exit is never missed (#50, #52).
+        captured[id] = process
+
+        let capturedProcess = process
+
+        // Box is local and synchronised with an NSLock; the @unchecked
+        // Sendable annotation is safe because all access is under the lock.
+        final class Box: @unchecked Sendable {
+            private let lock = NSLock()
+            private var status: Int32?
+            private var continuation: CheckedContinuation<Int32, Never>?
+
+            /// Try to resume an already-stored continuation with the exit
+            /// status. Returns true if a continuation was resumed.
+            func resume(with status: Int32) -> Bool {
+                lock.lock()
+                if let cont = continuation {
+                    continuation = nil
+                    lock.unlock()
+                    cont.resume(returning: status)
+                    return true
+                }
+                self.status = status
+                lock.unlock()
+                return false
+            }
+
+            /// Store a continuation, returning any status that arrived
+            /// before it. The caller must resume with the returned status.
+            func store(_ continuation: CheckedContinuation<Int32, Never>) -> Int32? {
+                lock.lock()
+                if let status = status {
+                    self.status = nil
+                    self.continuation = nil
+                    lock.unlock()
+                    return status
+                }
+                self.continuation = continuation
+                // A fast exit may have raced past the first nil-check.
+                if let status = status {
+                    self.status = nil
+                    self.continuation = nil
+                    lock.unlock()
+                    return status
+                }
+                lock.unlock()
+                return nil
+            }
+        }
+        let box = Box()
+        capturedProcess.terminationHandler = { proc in
+            _ = box.resume(with: proc.terminationStatus)
+        }
+
+        do {
+            try process.run()
+        } catch {
+            _ = box.resume(with: -1)
+            captured.removeValue(forKey: id)
+            preKillHooks.removeValue(forKey: id)
+            emit(.error(id: id, message: error.localizedDescription))
+            throw ProcessError.spawnFailed("\(binary.path): \(error.localizedDescription)")
+        }
+
+        // Close the parent write ends so readDataToEndOfFile() gets EOF
+        // as soon as the child exits; the child still has its own copies.
+        try? stdoutPipe.fileHandleForWriting.close()
+        try? stderrPipe.fileHandleForWriting.close()
+
+        return await withTaskCancellationHandler {
+            async let outData = Task.detached {
+                stdoutPipe.fileHandleForReading.readDataToEndOfFile()
+            }.value
+            async let errData = Task.detached {
+                stderrPipe.fileHandleForReading.readDataToEndOfFile()
+            }.value
+
+            let code = await withCheckedContinuation { continuation in
+                if let status = box.store(continuation) {
+                    continuation.resume(returning: status)
+                }
+            }
+
+            let (out, err) = await (outData, errData)
+
+            // Emit the real exit code once, regardless of whether kill()
+            // already removed the id from `captured`.
+            _ = captured.removeValue(forKey: id)
+            preKillHooks.removeValue(forKey: id)
+            emit(.exit(id: id, code: code))
+
+            return CapturedResult(
+                stdout: String(decoding: out, as: UTF8.self),
+                stderr: String(decoding: err, as: UTF8.self),
+                exitCode: code
+            )
+        } onCancel: { [weak self] in
+            // If the awaiting Task is cancelled, terminate the child so
+            // callers like runApplycal never replace a good profile with
+            // a truncated tmp.
+            if capturedProcess.isRunning {
+                capturedProcess.terminate()
+            }
+            Task { [weak self] in
+                await self?.kill(id: id)
+            }
+        }
+    }
+
+    // MARK: - stdin
+
+    /// Writes the exact bytes (caller includes `\n`) to a child's stdin
+    /// and flushes (docs/03 §stdin protocol).
+    public func sendStdin(id: String, bytes: Data) throws {
+        guard let child = children[id] else { throw ProcessError.unknownID(id) }
+        guard let handle = child.stdin else {
+            throw ProcessError.stdinFailed("stdin closed for \(id)")
+        }
+        do {
+            try handle.write(contentsOf: bytes)
+        } catch {
+            throw ProcessError.stdinFailed("\(id): \(error.localizedDescription)")
+        }
+    }
+
+    public func sendStdin(id: String, text: String) throws {
+        try sendStdin(id: id, bytes: Data(text.utf8))
+    }
+
+    // MARK: - Partial-line flush
+
+    /// Emits the current unterminated tail of a streaming child's stdout
+    /// and stderr as ordinary lines.  Callers (e.g. `colprof`) use this
+    /// to flush progress dots without waiting for a newline.
+    public func flushPartialLine(id: String) {
+        guard var child = children[id], !child.finalized else { return }
+
+        if let tail = child.stdoutDecoder.flushPartial() {
+            if tail.hasPrefix(Self.rowColorsPrefix) {
+                let payload = Data(tail.dropFirst(Self.rowColorsPrefix.count).utf8)
+                emit(.jsonRow(id: id, payload: payload))
+            } else {
+                emit(.stdout(id: id, line: tail))
+            }
+        }
+        if let tail = child.stderrDecoder.flushPartial() {
+            emit(.stderr(id: id, line: tail))
+        }
+
+        children[id] = child
+    }
+
+    // MARK: - Kill
+
+    /// Terminates a child.  First runs any registered pre-kill hook, then
+    /// drops stdin and signals the process.  For streaming children the
+    /// `exit` event is emitted once both stdout and stderr EOFs have been
+    /// seen (or the watchdog finalizes).  For captured children the real
+    /// exit code is emitted by `runCaptured` itself.
+    public func kill(id: String) async {
+        if let hook = preKillHooks.removeValue(forKey: id) {
+            await hook()
+        }
+
+        if var child = children[id] {
+            try? child.stdin?.close()
+            child.stdin = nil
+            children[id] = child
+
+            if child.process.isRunning {
+                child.process.terminate()
+            } else if child.pendingExitCode == nil {
+                // The process already exited but `didTerminate` has not
+                // run; synthesize it so `maybeFinalize` can fire.
+                didTerminate(id: id, code: child.process.terminationStatus)
+            }
+            return
+        }
+
+        if let process = captured[id] {
+            if process.isRunning { process.terminate() }
+            // Do not emit `.exit` here; `runCaptured` emits the real code
+            // after the process reaps.
+            return
+        }
+    }
+
+    /// Terminates every running child; returns how many were signaled
+    /// (`kill_all_processes`, docs/03). Mandatory on app exit (#147/#149).
+    @discardableResult
+    public func killAll() async -> Int {
+        let ids = runningIDs
+        for id in ids { await kill(id: id) }
+        return ids.count
+    }
+
+    // MARK: - Force kill (SIGKILL fallback)
+
+    /// Sends `SIGKILL` to a streaming child if it is still running.
+    /// Used by the finalization watchdog when a graceful `terminate()`
+    /// does not cause the process to exit.
+    public func forceKill(id: String) {
+        guard let child = children[id],
+              !child.finalized,
+              child.process.isRunning
+        else { return }
+
+        let pid = child.process.processIdentifier
+        guard pid > 0 else { return }
+        _ = Darwin.kill(pid, SIGKILL)
+    }
+
+    // MARK: - Internals
+
+    private func childEnvironment(extra: [String: String]) -> [String: String] {
+        var env = ProcessInfo.processInfo.environment
+        env["ARGYLL_NOT_INTERACTIVE"] = "1"
+        for (key, value) in extra { env[key] = value }
+        return env
+    }
+
+    private func ingestOutput(
+        _ data: Data,
+        id: String,
+        isStderr: Bool,
+        handle: FileHandle
+    ) {
+        guard var child = children[id] else { return }
+
+        if data.isEmpty {
+            // EOF on this pipe.
+            handle.readabilityHandler = nil
+            if isStderr { child.stderrEOF = true } else { child.stdoutEOF = true }
+            children[id] = child
+            maybeFinalize(id: id)
+            return
+        }
+
+        let lines: [String] = isStderr
+            ? child.stderrDecoder.feed(data)
+            : child.stdoutDecoder.feed(data)
+        children[id] = child
+
+        let log = AppLogger(category: "subprocess")
+        for line in lines {
+            if !isStderr, line.hasPrefix(Self.rowColorsPrefix) {
+                let payload = Data(line.dropFirst(Self.rowColorsPrefix.count).utf8)
+                emit(.jsonRow(id: id, payload: payload))
+            } else if isStderr {
+                log.warn("[\(id)] \(line)")
+                emit(.stderr(id: id, line: line))
+            } else {
+                log.info("[\(id)] \(line)")
+                emit(.stdout(id: id, line: line))
+            }
+        }
+    }
+
+    private func didTerminate(id: String, code: Int32) {
+        guard var child = children[id], !child.finalized else { return }
+        child.pendingExitCode = code
+        try? child.stdin?.close()
+        child.stdin = nil
+
+        // Start a watchdog in case the `readabilityHandler` EOFs never
+        // arrive after the process exits (e.g. a hung pipe).
+        child.finalizeTask = Task { [weak self] in
+            try? await Task.sleep(for: .seconds(2))
+            guard let self else { return }
+            await self.forceKill(id: id)
+            await self.forceFinalize(id: id)
+        }
+
+        children[id] = child
+        maybeFinalize(id: id)
+    }
+
+    /// Emits `exit` once the child has terminated *and* both pipes have
+    /// drained to EOF, so no buffered output is lost.
+    private func maybeFinalize(id: String) {
+        guard var child = children[id],
+              let code = child.pendingExitCode,
+              child.stdoutEOF, child.stderrEOF,
+              !child.finalized
+        else { return }
+
+        child.finalized = true
+        child.finalizeTask?.cancel()
+        child.finalizeTask = nil
+        children.removeValue(forKey: id)
+        preKillHooks.removeValue(forKey: id)
+
+        // Flush unterminated tail lines.
+        if var decoder = Optional(child.stdoutDecoder),
+           let tail = decoder.finish() {
+            if tail.hasPrefix(Self.rowColorsPrefix) {
+                emit(.jsonRow(id: id, payload: Data(tail.dropFirst(Self.rowColorsPrefix.count).utf8)))
+            } else {
+                emit(.stdout(id: id, line: tail))
+            }
+        }
+        if var decoder = Optional(child.stderrDecoder),
+           let tail = decoder.finish() {
+            emit(.stderr(id: id, line: tail))
+        }
+        emit(.exit(id: id, code: code))
+    }
+
+    /// Forces finalization even when one or both EOFs are missing.
+    /// Used by the `didTerminate` watchdog.
+    private func forceFinalize(id: String) {
+        guard var child = children[id], !child.finalized else { return }
+
+        if child.pendingExitCode == nil {
+            child.pendingExitCode = -9
+        }
+        child.stdoutEOF = true
+        child.stderrEOF = true
+        child.finalizeTask?.cancel()
+        child.finalizeTask = nil
+        children[id] = child
+        maybeFinalize(id: id)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ApplycalArgs.swift

@@ -0,0 +1,50 @@
+import Foundation
+
+/// Errors during `applycal` argv construction.
+public enum ApplycalArgError: LocalizedError, Equatable, Sendable {
+    case invalidCalibrationPath
+    case invalidInputProfileURL
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidCalibrationPath:
+            return "Calibration path is invalid or empty"
+        case .invalidInputProfileURL:
+            return "Input profile path is invalid or empty"
+        }
+    }
+}
+
+/// Pure argv builder for Argyll's `applycal` tool.
+///
+/// `applycal` is always run captured, never streamed.
+public enum ApplycalArgs {
+
+    /// Builds `applycal -v -a {cal} {input} [{output}]`.
+    ///
+    /// `-u` (unapply) is rejected at the builder level — the UI never
+    /// sends it (docs/04 §7.2).
+    public static func build(config: ApplycalConfig) throws -> [String] {
+        let cal = config.calibrationPath.trimmingCharacters(in: .whitespaces)
+        guard !cal.isEmpty else { throw ApplycalArgError.invalidCalibrationPath }
+
+        let input = config.inputProfileURL.path
+        guard !input.isEmpty else { throw ApplycalArgError.invalidInputProfileURL }
+
+        var args: [String] = ["-v"]
+        if config.unapply {
+            // Defensive: should never be called from the UI.
+            args.append("-u")
+        } else {
+            args.append("-a")
+        }
+
+        args.append(contentsOf: [cal, input])
+
+        if let output = config.outputProfileURL?.path, !output.isEmpty {
+            args.append(output)
+        }
+
+        return args
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ApplycalConfig.swift

@@ -0,0 +1,22 @@
+import Foundation
+
+/// Configuration for an Argyll `applycal` run.
+public struct ApplycalConfig: Sendable, Equatable {
+    public var calibrationPath: String
+    public var inputProfileURL: URL
+    public var outputProfileURL: URL?
+    public var unapply: Bool
+
+    /// In-place when `outputProfileURL` is `nil`.
+    public init(
+        calibrationPath: String,
+        inputProfileURL: URL,
+        outputProfileURL: URL? = nil,
+        unapply: Bool = false
+    ) {
+        self.calibrationPath = calibrationPath
+        self.inputProfileURL = inputProfileURL
+        self.outputProfileURL = outputProfileURL
+        self.unapply = unapply
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ColprofArgs.swift

@@ -0,0 +1,79 @@
+import Foundation
+
+/// Errors during `colprof` argv construction.
+public enum ColprofArgError: LocalizedError, Equatable, Sendable {
+    case invalidBasename(String)
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidBasename(let name):
+            return "Invalid colprof basename: \(name)"
+        }
+    }
+}
+
+/// Pure argv builder for Argyll's `colprof` tool.
+public enum ColprofArgs {
+
+    /// Builds `colprof` argv per the Gronod fork protocol.
+    ///
+    /// Always `-v -a {algorithm} -q {quality}`. Optional flags are added
+    /// only when their fields are non-empty and meaningful. `-f` has
+    /// special handling for "none" (omit), "" (bare flag), and a custom
+    /// `.sp` path (passed through). `-c`/`-d` viewing conditions are
+    /// skipped when set to "none".
+    public static func build(config: ColprofConfig) throws -> [String] {
+        let cleanBasename = try PathSecurity.sanitizeBasename(config.basename)
+
+        var args: [String] = ["-v"]
+
+        args.append(contentsOf: ["-a", config.algorithm])
+        args.append(contentsOf: ["-q", config.quality])
+
+        if let intent = config.intent?.trimmingCharacters(in: .whitespaces), !intent.isEmpty {
+            args.append(contentsOf: ["-t", intent])
+        }
+
+        if let fwa = config.fwa?.trimmingCharacters(in: .whitespaces) {
+            switch fwa.lowercased() {
+            case "none", "":
+                // "none" omits the flag; an explicit empty string means bare -f.
+                if fwa.isEmpty {
+                    args.append("-f")
+                }
+            default:
+                args.append(contentsOf: ["-f", fwa])
+            }
+        }
+
+        if let illuminant = config.illuminant?.trimmingCharacters(in: .whitespaces), !illuminant.isEmpty {
+            args.append(contentsOf: ["-i", illuminant])
+        }
+
+        if let observer = config.observer?.trimmingCharacters(in: .whitespaces), !observer.isEmpty {
+            args.append(contentsOf: ["-o", observer])
+        }
+
+        if let inputCond = config.inputViewingCond?.trimmingCharacters(in: .whitespaces),
+           !inputCond.isEmpty, inputCond.lowercased() != "none" {
+            args.append(contentsOf: ["-c", inputCond])
+        }
+
+        if let outputCond = config.outputViewingCond?.trimmingCharacters(in: .whitespaces),
+           !outputCond.isEmpty, outputCond.lowercased() != "none" {
+            args.append(contentsOf: ["-d", outputCond])
+        }
+
+        let profileDescription = config.description?.trimmingCharacters(in: .whitespaces)
+        if let description = profileDescription, !description.isEmpty {
+            args.append(contentsOf: ["-D", description])
+        }
+
+        if let copyright = config.copyright?.trimmingCharacters(in: .whitespaces), !copyright.isEmpty {
+            args.append(contentsOf: ["-C", copyright])
+        }
+
+        args.append(cleanBasename)
+        return args
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ColprofConfig.swift

@@ -0,0 +1,45 @@
+import Foundation
+
+/// Configuration for an Argyll `colprof` run (issue #23, docs/16).
+public struct ColprofConfig: Sendable, Equatable {
+    public var algorithm: String
+    public var quality: String
+    public var intent: String?
+    public var fwa: String?
+    public var illuminant: String?
+    public var observer: String?
+    public var inputViewingCond: String?
+    public var outputViewingCond: String?
+    public var description: String?
+    public var copyright: String?
+    public var basename: String
+    public var workingDirectory: URL?
+
+    public init(
+        algorithm: String = "l",
+        quality: String = "m",
+        intent: String? = nil,
+        fwa: String? = nil,
+        illuminant: String? = nil,
+        observer: String? = nil,
+        inputViewingCond: String? = nil,
+        outputViewingCond: String? = nil,
+        description: String? = nil,
+        copyright: String? = nil,
+        basename: String,
+        workingDirectory: URL? = nil
+    ) {
+        self.algorithm = algorithm
+        self.quality = quality
+        self.intent = intent
+        self.fwa = fwa
+        self.illuminant = illuminant
+        self.observer = observer
+        self.inputViewingCond = inputViewingCond
+        self.outputViewingCond = outputViewingCond
+        self.description = description
+        self.copyright = copyright
+        self.basename = basename
+        self.workingDirectory = workingDirectory
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ColprofProgress.swift

@@ -0,0 +1,30 @@
+import Foundation
+
+/// Classified `colprof` stdout progress milestone.
+public enum ColprofProgress: Sendable, Equatable {
+    case gamutMapping
+    case fittingClut
+    case writingIcc
+    case unknown
+}
+
+/// Parses `colprof` plaintext progress (docs/16 §6.3).
+///
+/// The Gronod fork supports `-u` JSON, but ICCery v2.0 does not pass it.
+/// Progress is therefore inferred from case-insensitive substring matches.
+public enum ColprofProgressClassifier {
+
+    public static func classify(line: String) -> ColprofProgress {
+        let lower = line.lowercased()
+        if lower.contains("gamut mapping") {
+            return .gamutMapping
+        }
+        if lower.contains("fitting") || lower.contains("clut") {
+            return .fittingClut
+        }
+        if lower.contains("writing") || lower.contains("icc profile") {
+            return .writingIcc
+        }
+        return .unknown
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/DriftAlert.swift

@@ -0,0 +1,49 @@
+import Foundation
+
+/// Computes a consecutive-breach warning from verification history.
+///
+/// A drift alert triggers when the most recent chronologically consecutive
+/// poor records form a run of at least two, and the first and last of that
+/// run are on distinct UTC days or at least one hour apart.
+public enum DriftAlert {
+
+    /// Returns an alert message, or `nil` when no consecutive breach exists.
+    public static func compute(from records: [VerificationRecord]) -> String? {
+        // Work in chronological order.
+        let chronological = records.sorted { $0.timestamp < $1.timestamp }
+
+        // Build the longest suffix of consecutive `.poor` records.
+        // Non-poor records break the run, so we stop at the first non-poor
+        // encountered from the end.
+        var run: [VerificationRecord] = []
+        for record in chronological.reversed() {
+            if record.status == .poor {
+                run.insert(record, at: 0)
+            } else {
+                break
+            }
+        }
+
+        guard run.count >= 2 else { return nil }
+
+        let first = run.first!
+        let last = run.last!
+
+        let sameDay = Calendar.utc.isDate(first.timestamp, inSameDayAs: last.timestamp)
+        let oneHour = last.timestamp.timeIntervalSince(first.timestamp) >= 3600
+
+        if !sameDay || oneHour {
+            return "Drift alert: poor results between \(first.id) and \(last.id)."
+        }
+
+        return nil
+    }
+}
+
+private extension Calendar {
+    static let utc: Calendar = {
+        var c = Calendar(identifier: .iso8601)
+        c.timeZone = TimeZone(identifier: "UTC")!
+        return c
+    }()
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/IccgamutArgs.swift

@@ -0,0 +1,29 @@
+import Foundation
+
+/// Errors during `iccgamut` argv construction.
+public enum IccgamutArgError: LocalizedError, Equatable, Sendable {
+    case invalidProfileURL
+
+    public var errorDescription: String? {
+        switch self {
+        case .invalidProfileURL:
+            return "iccgamut requires a valid profile path"
+        }
+    }
+}
+
+/// Pure argv builder for Argyll's `iccgamut` tool.
+public enum IccgamutArgs {
+
+    /// Builds `iccgamut -v -d {density} {profilePath}`.
+    ///
+    /// The caller is responsible for ensuring `density` is a positive
+    /// integer. `-d` here is surface **density**, not a directory.
+    public static func build(config: IccgamutConfig) throws -> [String] {
+        let path = config.profileURL.path
+        guard !path.isEmpty else { throw IccgamutArgError.invalidProfileURL }
+
+        let density = max(1, config.density)
+        return ["-v", "-d", "\(density)", path]
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/IccgamutConfig.swift

@@ -0,0 +1,12 @@
+import Foundation
+
+/// Configuration for an Argyll `iccgamut` run.
+public struct IccgamutConfig: Sendable, Equatable {
+    public var profileURL: URL
+    public var density: Int
+
+    public init(profileURL: URL, density: Int = 10) {
+        self.profileURL = profileURL
+        self.density = density
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/InstallProfileConfig.swift

@@ -0,0 +1,12 @@
+import Foundation
+
+/// Configuration for a profile installation.
+public struct InstallProfileConfig: Sendable, Equatable {
+    public var sourceURL: URL
+    public var options: InstallProfileOptions
+
+    public init(sourceURL: URL, options: InstallProfileOptions = InstallProfileOptions()) {
+        self.sourceURL = sourceURL
+        self.options = options
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/InstallProfileOptions.swift

@@ -0,0 +1,31 @@
+import Foundation
+
+/// Collision policy for profile installation.
+public enum ProfileCollisionPolicy: String, Sendable, Equatable, Codable, CaseIterable {
+    case overwrite
+    case rename
+    case cancel
+}
+
+/// Options for installing a finished profile into the OS colour store.
+public struct InstallProfileOptions: Sendable, Equatable, Codable {
+    public var forceOverwrite: Bool
+    public var preferSystem: Bool
+    public var collisionPolicy: ProfileCollisionPolicy
+    public var openColorPanel: Bool
+    public var calibrationNote: String?
+
+    public init(
+        forceOverwrite: Bool = false,
+        preferSystem: Bool = false,
+        collisionPolicy: ProfileCollisionPolicy = .cancel,
+        openColorPanel: Bool = false,
+        calibrationNote: String? = nil
+    ) {
+        self.forceOverwrite = forceOverwrite
+        self.preferSystem = preferSystem
+        self.collisionPolicy = collisionPolicy
+        self.openColorPanel = openColorPanel
+        self.calibrationNote = calibrationNote
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/InstallProfileResult.swift

@@ -0,0 +1,30 @@
+import Foundation
+
+/// Result of installing a profile into the OS colour store.
+public struct InstallProfileResult: Sendable, Equatable, Codable {
+    public var destPath: String
+    public var registered: Bool
+    public var overwritten: Bool
+    public var renamed: Bool
+    public var openedPanel: Bool
+    public var message: String
+    public var calibrationNote: String?
+
+    public init(
+        destPath: String,
+        registered: Bool,
+        overwritten: Bool,
+        renamed: Bool,
+        openedPanel: Bool,
+        message: String,
+        calibrationNote: String? = nil
+    ) {
+        self.destPath = destPath
+        self.registered = registered
+        self.overwritten = overwritten
+        self.renamed = renamed
+        self.openedPanel = openedPanel
+        self.message = message
+        self.calibrationNote = calibrationNote
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ProfcheckArgs.swift

@@ -0,0 +1,37 @@
+import Foundation
+
+/// Errors during `profcheck` argv construction.
+public enum ProfcheckArgError: LocalizedError, Equatable, Sendable {
+    case missingTi3
+    case missingIcc
+    case invalidTi3Path
+
+    public var errorDescription: String? {
+        switch self {
+        case .missingTi3:
+            return "profcheck requires a .ti3 file"
+        case .missingIcc:
+            return "profcheck requires a profile (.icc/.icm)"
+        case .invalidTi3Path:
+            return "profcheck .ti3 path is invalid"
+        }
+    }
+}
+
+/// Pure argv builder for Argyll's `profcheck` tool.
+public enum ProfcheckArgs {
+
+    /// Builds `profcheck -v -k -s -u {ti3Path} {iccPath}`.
+    ///
+    /// The `-u` here is the Gronod fork JSON report flag, not the
+    /// generic `-u` auto-fix that some Argyll builds use.
+    public static func build(config: ProfcheckConfig) throws -> [String] {
+        let ti3Path = config.ti3URL.path
+        let iccPath = config.iccURL.path
+
+        guard !ti3Path.isEmpty else { throw ProfcheckArgError.missingTi3 }
+        guard !iccPath.isEmpty else { throw ProfcheckArgError.missingIcc }
+
+        return ["-v", "-k", "-s", "-u", ti3Path, iccPath]
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ProfcheckConfig.swift

@@ -0,0 +1,12 @@
+import Foundation
+
+/// Configuration for an Argyll `profcheck` run.
+public struct ProfcheckConfig: Sendable, Equatable {
+    public var ti3URL: URL
+    public var iccURL: URL
+
+    public init(ti3URL: URL, iccURL: URL) {
+        self.ti3URL = ti3URL
+        self.iccURL = iccURL
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ProfcheckParser.swift

@@ -0,0 +1,217 @@
+import Foundation
+
+/// Errors returned when `profcheck` output cannot be parsed.
+public enum ProfcheckParserError: LocalizedError, Equatable, Sendable {
+    case unparseable
+    case jsonDecodingFailed
+
+    public var errorDescription: String? {
+        switch self {
+        case .unparseable:
+            return "Could not parse profcheck report"
+        case .jsonDecodingFailed:
+            return "profcheck JSON report could not be decoded"
+        }
+    }
+}
+
+/// Parses the mixed JSON/text output from `profcheck -v -k -s -u`.
+public enum ProfcheckParser {
+
+    /// Parsing order (issue #25):
+    /// 1. Patch count from `No of test patches = N`.
+    /// 2. JSON objects; prefer one with `event == "report"` or `*_de2000` keys.
+    /// 3. Legacy text: `Profile check complete, errors(CIEDE2000): max. = X, avg. = Y, RMS = Z`.
+    /// 4. Broad regex fallback.
+    /// 5. If no metrics found, return a report whose `warning` is set.
+    public static func parse(_ output: String) -> ProfcheckReport {
+        var report = ProfcheckReport()
+
+        // 1. Patch count.
+        let patchRegex = try? NSRegularExpression(
+            pattern: #"No of test patches\s*=\s*(\d+)"#,
+            options: [.caseInsensitive]
+        )
+        if let match = patchRegex?.firstMatch(
+            in: output,
+            options: [],
+            range: NSRange(output.startIndex..., in: output)
+        ), let range = Range(match.range(at: 1), in: output) {
+            let count = Int(output[range])
+            report.patchCount = count
+        }
+
+        // 2. JSON objects.
+        let jsonObjects = extractJSONObjects(from: output)
+        for object in jsonObjects {
+            if let event = object["event"] as? String, event == "report" {
+                if let parsed = metrics(from: object) {
+                    apply(metrics: parsed, to: &report)
+                    return report
+                }
+            }
+            if hasMetricKeys(object) {
+                if let parsed = metrics(from: object) {
+                    apply(metrics: parsed, to: &report)
+                    return report
+                }
+            }
+        }
+
+        // 3. Legacy text.
+        let textRegex = try? NSRegularExpression(
+            pattern: #"Profile check complete, errors\(CIEDE2000\): max\.\s*=\s*([0-9.]+),\s*avg\.\s*=\s*([0-9.]+),\s*RMS\s*=\s*([0-9.]+)"#,
+            options: [.caseInsensitive]
+        )
+        if let match = textRegex?.firstMatch(
+            in: output,
+            options: [],
+            range: NSRange(output.startIndex..., in: output)
+        ) {
+            let numbers = (1...3).compactMap { i -> Double? in
+                guard let range = Range(match.range(at: i), in: output) else { return nil }
+                return Double(output[range])
+            }
+            if numbers.count == 3 {
+                report.maxDE = numbers[0]
+                report.avgDE = numbers[1]
+                report.rmsDE = numbers[2]
+                report.status = report.avgDE.map { VerificationStatus.from(avgDE: $0) }
+                return report
+            }
+        }
+
+        // 4. Broad regex fallback.
+        if let fallback = parseRegexFallback(output) {
+            var merged = fallback
+            merged.patchCount = report.patchCount
+            return merged
+        }
+
+        // 5. Unparseable.
+        report.warning = "profcheck output did not contain a recognisable report."
+        return report
+    }
+
+    // MARK: - JSON extraction
+
+    private static func extractJSONObjects(from output: String) -> [[String: Any]] {
+        var objects: [[String: Any]] = []
+        var start: String.Index?
+        var depth = 0
+
+        for index in output.indices {
+            let char = output[index]
+            if char == "{" {
+                if depth == 0 {
+                    start = index
+                }
+                depth += 1
+            } else if char == "}" {
+                if depth > 0 {
+                    depth -= 1
+                    if depth == 0, let start = start {
+                        let jsonString = String(output[start...index])
+                        if let data = jsonString.data(using: .utf8),
+                           let object = try? JSONSerialization.jsonObject(with: data) as? [String: Any] {
+                            objects.append(object)
+                        }
+                    }
+                }
+            }
+        }
+
+        return objects
+    }
+
+    private static func hasMetricKeys(_ object: [String: Any]) -> Bool {
+        let keys = [
+            "avg_de", "avg_de2000",
+            "peak_de", "peak_de2000", "max_de",
+            "rms", "rms_de"
+        ]
+        return keys.contains { object[$0] != nil }
+    }
+
+    private struct Metrics {
+        var avg: Double?
+        var max: Double?
+        var rms: Double?
+    }
+
+    private static func metrics(from object: [String: Any]) -> Metrics? {
+        var m = Metrics()
+        m.avg = doubleValue(for: "avg_de2000", in: object)
+            ?? doubleValue(for: "avg_de", in: object)
+        m.max = doubleValue(for: "peak_de2000", in: object)
+            ?? doubleValue(for: "peak_de", in: object)
+            ?? doubleValue(for: "max_de", in: object)
+            ?? doubleValue(for: "max_de2000", in: object)
+        m.rms = doubleValue(for: "rms", in: object)
+            ?? doubleValue(for: "rms_de", in: object)
+            ?? doubleValue(for: "rms_de2000", in: object)
+
+        guard m.avg != nil || m.max != nil || m.rms != nil else { return nil }
+        return m
+    }
+
+    private static func doubleValue(for key: String, in object: [String: Any]) -> Double? {
+        if let number = object[key] as? Double { return number }
+        if let number = object[key] as? NSNumber { return number.doubleValue }
+        if let string = object[key] as? String { return Double(string) }
+        return nil
+    }
+
+    private static func apply(metrics: Metrics, to report: inout ProfcheckReport) {
+        report.avgDE = metrics.avg
+        report.maxDE = metrics.max
+        report.rmsDE = metrics.rms
+        if let avg = metrics.avg {
+            report.status = VerificationStatus.from(avgDE: avg)
+        }
+    }
+
+    // MARK: - Regex fallback
+
+    private static func parseRegexFallback(_ output: String) -> ProfcheckReport? {
+        var report = ProfcheckReport()
+
+        let avgRegex = try? NSRegularExpression(
+            pattern: #"(?:avg\.?|average)\s*(?:=|:)\s*([0-9.]+)"#,
+            options: [.caseInsensitive]
+        )
+        let maxRegex = try? NSRegularExpression(
+            pattern: #"(?:max\.?|peak|maximum)\s*(?:=|:)\s*([0-9.]+)"#,
+            options: [.caseInsensitive]
+        )
+        let rmsRegex = try? NSRegularExpression(
+            pattern: #"(?:rms)\s*(?:=|:)\s*([0-9.]+)"#,
+            options: [.caseInsensitive]
+        )
+
+        report.avgDE = firstDouble(from: output, regex: avgRegex)
+        report.maxDE = firstDouble(from: output, regex: maxRegex)
+        report.rmsDE = firstDouble(from: output, regex: rmsRegex)
+
+        guard report.avgDE != nil || report.maxDE != nil || report.rmsDE != nil else {
+            return nil
+        }
+
+        if let avg = report.avgDE {
+            report.status = VerificationStatus.from(avgDE: avg)
+        }
+
+        return report
+    }
+
+    private static func firstDouble(from output: String, regex: NSRegularExpression?) -> Double? {
+        guard let regex = regex,
+              let match = regex.firstMatch(
+                in: output,
+                options: [],
+                range: NSRange(output.startIndex..., in: output)
+              ),
+              let range = Range(match.range(at: 1), in: output) else { return nil }
+        return Double(output[range])
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ProfcheckReport.swift

@@ -0,0 +1,31 @@
+import Foundation
+
+/// Parsed result from a `profcheck -u` run.
+public struct ProfcheckReport: Sendable, Equatable, Codable {
+    public var patchCount: Int?
+    public var avgDE: Double?
+    public var maxDE: Double?
+    public var rmsDE: Double?
+    public var status: VerificationStatus?
+    public var warning: String?
+
+    public var isValid: Bool {
+        avgDE != nil && maxDE != nil && rmsDE != nil
+    }
+
+    public init(
+        patchCount: Int? = nil,
+        avgDE: Double? = nil,
+        maxDE: Double? = nil,
+        rmsDE: Double? = nil,
+        status: VerificationStatus? = nil,
+        warning: String? = nil
+    ) {
+        self.patchCount = patchCount
+        self.avgDE = avgDE
+        self.maxDE = maxDE
+        self.rmsDE = rmsDE
+        self.status = status
+        self.warning = warning
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/ProfileInstaller.swift

@@ -0,0 +1,238 @@
+import Foundation
+
+/// Errors thrown by `ProfileInstaller`.
+public enum ProfileInstallError: LocalizedError, Equatable, Sendable {
+    case unsafeStem(String)
+    case sourceMissing
+    case sourceNotProfile
+    case sourceTooSmall
+    case systemRequiresAdminRights
+    case copyFailed(String)
+    case cancelled
+
+    public var errorDescription: String? {
+        switch self {
+        case .unsafeStem(let stem):
+            return "Profile name contains unsafe characters: \(stem)"
+        case .sourceMissing:
+            return "Source profile does not exist"
+        case .sourceNotProfile:
+            return "Source must be a .icc or .icm file"
+        case .sourceTooSmall:
+            return "Source file is too small to be a valid profile"
+        case .systemRequiresAdminRights:
+            return "Installing to /Library/ColorSync/Profiles requires administrator rights"
+        case .copyFailed(let reason):
+            return "Could not install profile: \(reason)"
+        case .cancelled:
+            return "Install cancelled"
+        }
+    }
+}
+
+/// Installs an ICC/ICM profile into the OS colour store.
+public enum ProfileInstaller {
+
+    /// Resolves the destination URL that `install` would write to for the
+    /// given source and options, without copying anything. Useful for
+    /// collision previews in the UI.
+    public static func resolveDestinationURL(
+        for config: InstallProfileConfig,
+        fileManager: FileManager = .default
+    ) throws -> URL {
+        let sourceURL = config.sourceURL
+        let ext = sourceURL.pathExtension.lowercased()
+        guard ext == "icc" || ext == "icm" else {
+            throw ProfileInstallError.sourceNotProfile
+        }
+
+        try validateSourceURL(sourceURL)
+
+        let destDir = destinationDirectory(for: config.options, fileManager: fileManager)
+        return destDir.appendingPathComponent(sourceURL.lastPathComponent)
+    }
+
+    /// Installs `sourceURL` into `~/Library/ColorSync/Profiles` or
+    /// `/Library/ColorSync/Profiles`. Always copies, never moves.
+    public static func install(
+        config: InstallProfileConfig,
+        fileManager: FileManager = .default
+    ) throws -> InstallProfileResult {
+        let fm = fileManager
+
+        // Source validation.
+        let sourceURL = config.sourceURL
+        guard fm.fileExists(atPath: sourceURL.path) else {
+            throw ProfileInstallError.sourceMissing
+        }
+
+        let ext = sourceURL.pathExtension.lowercased()
+        guard ext == "icc" || ext == "icm" else {
+            throw ProfileInstallError.sourceNotProfile
+        }
+
+        let attrs = try? fm.attributesOfItem(atPath: sourceURL.path)
+        let size = attrs?[.size] as? UInt64 ?? 0
+        guard size >= 128 else {
+            throw ProfileInstallError.sourceTooSmall
+        }
+
+        try validateSourceURL(sourceURL)
+
+        // Destination directory.
+        let destURL = try resolveDestinationURL(for: config, fileManager: fm)
+        try? fm.createDirectory(
+            at: destURL.deletingLastPathComponent(),
+            withIntermediateDirectories: true
+        )
+
+        // Collision resolution.
+        let destExists = fm.fileExists(atPath: destURL.path)
+        if destExists {
+            if config.options.forceOverwrite {
+                return try performInstall(
+                    from: sourceURL,
+                    to: destURL,
+                    options: config.options,
+                    fileManager: fm,
+                    overwritten: true,
+                    renamed: false
+                )
+            } else if config.options.collisionPolicy == .rename {
+                let epoch = Int(Date().timeIntervalSince1970)
+                let stem = sourceURL.deletingPathExtension().lastPathComponent
+                let renamedURL = destURL.deletingLastPathComponent()
+                    .appendingPathComponent("\(stem)-\(epoch).\(ext)")
+                return try performInstall(
+                    from: sourceURL,
+                    to: renamedURL,
+                    options: config.options,
+                    fileManager: fm,
+                    overwritten: false,
+                    renamed: true
+                )
+            } else if config.options.collisionPolicy == .cancel {
+                throw ProfileInstallError.cancelled
+            } else {
+                // Default with askBeforeOverwrite — the app must decide.
+                throw ProfileInstallError.copyFailed("destination already exists")
+            }
+        }
+
+        return try performInstall(
+            from: sourceURL,
+            to: destURL,
+            options: config.options,
+            fileManager: fm,
+            overwritten: false,
+            renamed: false
+        )
+    }
+
+    // MARK: - Private helpers
+
+    private static func validateSourceURL(_ sourceURL: URL) throws {
+        let path = sourceURL.path
+        let stem = sourceURL.deletingPathExtension().lastPathComponent
+
+        // Reject backslashes anywhere in the path.
+        guard !path.contains("\\") else {
+            throw ProfileInstallError.unsafeStem(stem)
+        }
+
+        // Reject any path component that is literally "." or "..".
+        // This allows names like "foo..bar" while blocking real traversal.
+        for component in sourceURL.pathComponents {
+            if component == "." || component == ".." {
+                throw ProfileInstallError.unsafeStem(stem)
+            }
+        }
+    }
+
+    private static func destinationDirectory(
+        for options: InstallProfileOptions,
+        fileManager: FileManager
+    ) -> URL {
+        if options.preferSystem {
+            return URL(fileURLWithPath: "/Library/ColorSync/Profiles")
+        } else {
+            return fileManager.homeDirectoryForCurrentUser
+                .appendingPathComponent("Library/ColorSync/Profiles")
+        }
+    }
+
+    private static func performInstall(
+        from sourceURL: URL,
+        to destURL: URL,
+        options: InstallProfileOptions,
+        fileManager: FileManager,
+        overwritten: Bool,
+        renamed: Bool
+    ) throws -> InstallProfileResult {
+        let fm = fileManager
+        let tmpURL = destURL.appendingPathExtension("iccery-install.tmp")
+
+        // Remove stale tmp.
+        try? fm.removeItem(at: tmpURL)
+
+        do {
+            try fm.copyItem(at: sourceURL, to: tmpURL)
+
+            let attrs = try? fm.attributesOfItem(atPath: tmpURL.path)
+            let tmpSize = attrs?[.size] as? UInt64 ?? 0
+            guard tmpSize >= 128 else {
+                try? fm.removeItem(at: tmpURL)
+                throw ProfileInstallError.sourceTooSmall
+            }
+
+            if fm.fileExists(atPath: destURL.path) {
+                _ = try fm.replaceItemAt(destURL, withItemAt: tmpURL)
+            } else {
+                try fm.moveItem(at: tmpURL, to: destURL)
+            }
+        } catch {
+            try? fm.removeItem(at: tmpURL)
+
+            // Surface a clear admin-rights hint when writing to system.
+            if destURL.path.hasPrefix("/Library/") && !fm.fileExists(atPath: destURL.path) {
+                throw ProfileInstallError.systemRequiresAdminRights
+            }
+
+            if let installError = error as? ProfileInstallError {
+                throw installError
+            }
+            throw ProfileInstallError.copyFailed(error.localizedDescription)
+        }
+
+        let registered = fm.fileExists(atPath: destURL.path)
+
+        var openedPanel = false
+        if options.openColorPanel {
+            openedPanel = openColorSyncUtility()
+        }
+
+        return InstallProfileResult(
+            destPath: destURL.path,
+            registered: registered,
+            overwritten: overwritten,
+            renamed: renamed,
+            openedPanel: openedPanel,
+            message: "Profile installed to \(destURL.path)",
+            calibrationNote: options.calibrationNote
+        )
+    }
+
+    private static func openColorSyncUtility() -> Bool {
+        let task = Process()
+        task.launchPath = "/usr/bin/open"
+        task.arguments = ["-a", "ColorSync Utility"]
+        task.environment = ["ARGYLL_NOT_INTERACTIVE": "1"]
+        do {
+            try task.run()
+            task.waitUntilExit()
+        } catch {
+            return false
+        }
+        return true
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/VerificationHistoryStore.swift

@@ -0,0 +1,122 @@
+import Foundation
+
+/// Persistence for `VerificationRecord` entries.
+public actor VerificationHistoryStore {
+
+    /// Default cap.
+    public static let defaultCapacity = 1000
+
+    /// Path to the JSON store.
+    public let url: URL
+
+    /// In-memory cache, kept in sync with disk.
+    private var records: [VerificationRecord] = []
+
+    private let capacity: Int
+    private let encoder: JSONEncoder
+    private let decoder: JSONDecoder
+
+    public init(
+        url: URL = AppPaths.appDataDir.appendingPathComponent("verification_history.json"),
+        capacity: Int = defaultCapacity
+    ) {
+        self.url = url
+        self.capacity = capacity
+
+        self.encoder = JSONEncoder()
+        self.encoder.dateEncodingStrategy = .iso8601
+        self.encoder.outputFormatting = [.prettyPrinted, .sortedKeys]
+
+        self.decoder = JSONDecoder()
+        self.decoder.dateDecodingStrategy = .iso8601
+    }
+
+    /// Loads records from disk. Returns the existing cache if already loaded.
+    ///
+    /// Throws when the file exists but cannot be parsed; the existing file
+    /// is never overwritten in that case.
+    public func load() throws -> [VerificationRecord] {
+        guard records.isEmpty else { return records }
+        let fm = FileManager.default
+        guard fm.fileExists(atPath: url.path),
+              let data = try? Data(contentsOf: url) else { return [] }
+        records = try decoder.decode([VerificationRecord].self, from: data)
+        return records
+    }
+
+    /// Returns all records.
+    public func all() -> [VerificationRecord] {
+        records
+    }
+
+    /// Records matching the optional printer filter.
+    public func filtered(by printer: String?) -> [VerificationRecord] {
+        guard let printer = printer, !printer.isEmpty else { return records }
+        return records.filter { $0.printerName == printer }
+    }
+
+    /// Appends a record, trims to capacity, and writes atomically.
+    ///
+    /// Loads the existing history first and propagates any load error so an
+    /// unparseable file is never overwritten.
+    @discardableResult
+    public func append(_ record: VerificationRecord) throws -> [VerificationRecord] {
+        try load()
+
+        var updated = records
+        updated.append(record)
+        if updated.count > capacity {
+            updated.sort { $0.timestamp < $1.timestamp }
+            updated = Array(updated.suffix(capacity))
+        }
+
+        try write(updated)
+        records = updated
+        return updated
+    }
+
+    /// Removes all history and updates disk.
+    public func clear() throws {
+        try write([])
+        records = []
+    }
+
+    /// RFC-4180 CSV export.
+    public func exportCSV() -> String {
+        var lines: [String] = [
+            csvRow(["id", "profile_name", "printer_name", "avg_de", "max_de", "rms_de", "patch_count", "status", "timestamp"])
+        ]
+
+        for record in records {
+            lines.append(csvRow([
+                record.id,
+                record.profileName,
+                record.printerName,
+                String(record.avgDE),
+                String(record.maxDE),
+                String(record.rmsDE),
+                String(record.patchCount),
+                record.status.rawValue,
+                ISO8601DateFormatter().string(from: record.timestamp)
+            ]))
+        }
+
+        return lines.joined(separator: "\n") + "\n"
+    }
+
+    /// Writes `records` through a temp file and rename.
+    private func write(_ records: [VerificationRecord]) throws {
+        let data = try encoder.encode(records)
+        try AtomicFileWriter.write(data, to: url)
+    }
+
+    private func csvRow(_ fields: [String]) -> String {
+        fields.map { field in
+            let escaped = field.replacingOccurrences(of: "\"", with: "\"\"")
+            if field.contains(",") || field.contains("\"") || field.contains("\n") || field.contains("\r") {
+                return "\"\(escaped)\""
+            }
+            return escaped
+        }.joined(separator: ",")
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/VerificationRecord.swift

@@ -0,0 +1,36 @@
+import Foundation
+
+/// A single entry in the verification history store.
+public struct VerificationRecord: Sendable, Equatable, Codable, Identifiable {
+    public var id: String
+    public var profileName: String
+    public var printerName: String
+    public var avgDE: Double
+    public var maxDE: Double
+    public var rmsDE: Double
+    public var patchCount: Int
+    public var status: VerificationStatus
+    public var timestamp: Date
+
+    public init(
+        id: String,
+        profileName: String,
+        printerName: String,
+        avgDE: Double,
+        maxDE: Double,
+        rmsDE: Double,
+        patchCount: Int,
+        status: VerificationStatus,
+        timestamp: Date
+    ) {
+        self.id = id
+        self.profileName = profileName
+        self.printerName = printerName
+        self.avgDE = avgDE
+        self.maxDE = maxDE
+        self.rmsDE = rmsDE
+        self.patchCount = patchCount
+        self.status = status
+        self.timestamp = timestamp
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Profile/VerificationStatus.swift

@@ -0,0 +1,32 @@
+import Foundation
+
+/// ICCery quality band for a verification run.
+///
+/// Bands are on the **average** ΔE₀₀:
+/// - < 1.0 → Excellent
+/// - < 2.0 → Good
+/// - < 3.5 → Acceptable
+/// - ≥ 3.5 → Warning
+public enum VerificationStatus: String, Sendable, Equatable, Codable, CaseIterable {
+    case excellent
+    case good
+    case acceptable
+    case poor
+
+    public var displayName: String {
+        switch self {
+        case .excellent: return "Excellent"
+        case .good: return "Good"
+        case .acceptable: return "Acceptable"
+        case .poor: return "Warning"
+        }
+    }
+
+    /// Returns the quality band for the given average ΔE₀₀.
+    public static func from(avgDE: Double) -> VerificationStatus {
+        if avgDE < 1.0 { return .excellent }
+        if avgDE < 2.0 { return .good }
+        if avgDE < 3.5 { return .acceptable }
+        return .poor
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Settings/AppSettings.swift

@@ -0,0 +1,251 @@
+import Foundation
+
+/// Legacy M1 preset shape (`name` + opaque string dictionary). Retained
+/// solely to decode and migrate pre-M2 `settings.json`; new code uses
+/// `ProfilingPreset` (docs/22 §ProfilingPreset).
+public struct CustomPreset: Codable, Equatable, Sendable {
+    public var name: String
+    /// Opaque per-stage form values — keyed by field id.
+    public var values: [String: String]
+
+    public init(name: String, values: [String: String] = [:]) {
+        self.name = name
+        self.values = values
+    }
+}
+
+/// Where `install_profile` drops finished profiles (docs/22).
+public enum InstallLocation: String, Codable, Sendable, CaseIterable {
+    case user
+    case system
+}
+
+/// `settings.json` model (docs/22). snake_case keys match the v1 file
+/// so field names stay identical across rewrites.
+///
+/// Decoding is tolerant: missing keys take documented defaults and each
+/// `custom_presets` element is tried as a typed `ProfilingPreset` first
+/// and as a legacy M1 `CustomPreset` second — a malformed entry never
+/// drops the rest of the array (preset migration, issue #11).
+public struct AppSettings: Codable, Equatable, Sendable {
+
+    /// User override for Argyll binaries; `nil` → bundled sidecars.
+    public var argyllBinaryDir: String?
+
+    /// Stored but **never applied to argv** — Stage 2's own instrument
+    /// select is the live source (docs/04 §0.1).
+    public var defaultInstrument: String?
+
+    /// `nil` → `.debug` in debug builds, `.info` in release (#158).
+    public var logLevel: LogLevel?
+
+    public var deltaEGoodMax: Double
+    public var deltaEWarningMax: Double
+    public var customPresets: [ProfilingPreset]
+    public var enableI1Pro2Leds: Bool
+    public var calibrationStaleDays: Int
+    public var defaultInstallLocation: InstallLocation
+    public var askBeforeOverwriteProfile: Bool
+    public var openColorPanelAfterInstall: Bool
+
+    public init(
+        argyllBinaryDir: String? = nil,
+        defaultInstrument: String? = nil,
+        logLevel: LogLevel? = nil,
+        deltaEGoodMax: Double = 2.0,
+        deltaEWarningMax: Double = 5.0,
+        customPresets: [ProfilingPreset] = [],
+        enableI1Pro2Leds: Bool = false,
+        calibrationStaleDays: Int = 30,
+        defaultInstallLocation: InstallLocation = .user,
+        askBeforeOverwriteProfile: Bool = true,
+        openColorPanelAfterInstall: Bool = false
+    ) {
+        self.argyllBinaryDir = argyllBinaryDir
+        self.defaultInstrument = defaultInstrument
+        self.logLevel = logLevel
+        self.deltaEGoodMax = deltaEGoodMax
+        self.deltaEWarningMax = deltaEWarningMax
+        self.customPresets = customPresets
+        self.enableI1Pro2Leds = enableI1Pro2Leds
+        self.calibrationStaleDays = calibrationStaleDays
+        self.defaultInstallLocation = defaultInstallLocation
+        self.askBeforeOverwriteProfile = askBeforeOverwriteProfile
+        self.openColorPanelAfterInstall = openColorPanelAfterInstall
+    }
+
+    public static let `default` = AppSettings()
+
+    /// Effective log level — runtime state, not just persistence (#158).
+    public var effectiveLogLevel: LogLevel {
+        if let logLevel { return logLevel }
+        #if DEBUG
+        return .debug
+        #else
+        return .info
+        #endif
+    }
+
+    enum CodingKeys: String, CodingKey {
+        case argyllBinaryDir = "argyll_binary_dir"
+        case defaultInstrument = "default_instrument"
+        case logLevel = "log_level"
+        case deltaEGoodMax = "delta_e_good_max"
+        case deltaEWarningMax = "delta_e_warning_max"
+        case customPresets = "custom_presets"
+        case enableI1Pro2Leds = "enable_i1pro2_leds"
+        case calibrationStaleDays = "calibration_stale_days"
+        case defaultInstallLocation = "default_install_location"
+        case askBeforeOverwriteProfile = "ask_before_overwrite_profile"
+        case openColorPanelAfterInstall = "open_color_panel_after_install"
+    }
+
+    /// One element of `custom_presets`: typed first, legacy M1 second.
+    private enum AnyPreset: Decodable {
+        case typed(ProfilingPreset)
+        case legacy(CustomPreset)
+
+        init(from decoder: Decoder) throws {
+            if let p = try? ProfilingPreset(from: decoder) {
+                self = .typed(p)
+                return
+            }
+            self = .legacy(try CustomPreset(from: decoder))
+        }
+    }
+
+    public init(from decoder: Decoder) throws {
+        let c = try decoder.container(keyedBy: CodingKeys.self)
+        let d = AppSettings.default
+        argyllBinaryDir = try c.decodeIfPresent(String.self, forKey: .argyllBinaryDir) ?? d.argyllBinaryDir
+        defaultInstrument = try c.decodeIfPresent(String.self, forKey: .defaultInstrument) ?? d.defaultInstrument
+        logLevel = try c.decodeIfPresent(LogLevel.self, forKey: .logLevel) ?? d.logLevel
+        deltaEGoodMax = try c.decodeIfPresent(Double.self, forKey: .deltaEGoodMax) ?? d.deltaEGoodMax
+        deltaEWarningMax = try c.decodeIfPresent(Double.self, forKey: .deltaEWarningMax) ?? d.deltaEWarningMax
+        enableI1Pro2Leds = try c.decodeIfPresent(Bool.self, forKey: .enableI1Pro2Leds) ?? d.enableI1Pro2Leds
+        calibrationStaleDays = try c.decodeIfPresent(Int.self, forKey: .calibrationStaleDays) ?? d.calibrationStaleDays
+        defaultInstallLocation = try c.decodeIfPresent(InstallLocation.self, forKey: .defaultInstallLocation) ?? d.defaultInstallLocation
+        askBeforeOverwriteProfile = try c.decodeIfPresent(Bool.self, forKey: .askBeforeOverwriteProfile) ?? d.askBeforeOverwriteProfile
+        openColorPanelAfterInstall = try c.decodeIfPresent(Bool.self, forKey: .openColorPanelAfterInstall) ?? d.openColorPanelAfterInstall
+
+        // Per-element decode: typed presets win; a legacy M1 shape
+        // ({"name","values"}) migrates; unconvertible entries are
+        // skipped so one bad record never drops the array.
+        let elements = (try? c.decodeIfPresent(
+            [FailableDecodable<AnyPreset>].self, forKey: .customPresets
+        )) ?? nil
+        var migrated: [ProfilingPreset] = []
+        for (index, element) in (elements ?? []).enumerated() {
+            switch element.value {
+            case .typed(let preset):
+                migrated.append(preset)
+            case .legacy(let legacy):
+                if let converted = ProfilingPreset(migrating: legacy, index: index) {
+                    migrated.append(converted)
+                } else {
+                    AppLogger(category: "settings").warn(
+                        "Skipped unmigratable legacy preset: \(legacy.name)"
+                    )
+                }
+            case .none:
+                AppLogger(category: "settings").warn(
+                    "Skipped malformed preset entry at index \(index)"
+                )
+            }
+        }
+        customPresets = migrated
+    }
+
+    /// UI-facing validation. Strings are part of the contract (issue #5).
+    public static let errorNegativeDeltaE = "ΔE thresholds cannot be negative."
+    public static let errorThresholdOrder =
+        "Good ΔE threshold must be strictly less than the warning threshold."
+
+    /// All validation errors, in declaration order. Empty = valid.
+    public func validate() -> [String] {
+        var errors: [String] = []
+        if deltaEGoodMax < 0 || deltaEWarningMax < 0 {
+            errors.append(Self.errorNegativeDeltaE)
+        }
+        if deltaEGoodMax >= deltaEWarningMax {
+            errors.append(Self.errorThresholdOrder)
+        }
+        return errors
+    }
+
+    public var isValid: Bool { validate().isEmpty }
+}
+
+extension ProfilingPreset {
+
+    /// Migrates a legacy M1 `CustomPreset` (`name` + string values) to
+    /// the typed schema. Known keys are coerced; anything else is
+    /// ignored. Returns `nil` only when the name is unusable — a
+    /// deterministic `custom-{index}-{slug}` id is always produced.
+    init?(migrating legacy: CustomPreset, index: Int) {
+        let trimmedName = legacy.name.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !trimmedName.isEmpty else { return nil }
+
+        let v = legacy.values
+        func int(_ key: String) -> Int? {
+            v[key].flatMap { Int($0.trimmingCharacters(in: .whitespaces)) }
+        }
+        func double(_ key: String) -> Double? {
+            v[key].flatMap { Double($0.trimmingCharacters(in: .whitespaces)) }
+        }
+        func bool(_ key: String) -> Bool? {
+            v[key].flatMap { s in
+                switch s.trimmingCharacters(in: .whitespaces).lowercased() {
+                case "true", "1", "yes": return true
+                case "false", "0", "no": return false
+                default: return nil
+                }
+            }
+        }
+        func string(_ key: String) -> String? {
+            v[key].map { $0.trimmingCharacters(in: .whitespaces) }
+                .flatMap { $0.isEmpty ? nil : $0 }
+        }
+
+        let slug = trimmedName.lowercased()
+            .map { $0.isLetter || $0.isNumber ? $0 : "-" }
+            .reduce(into: "") { $0.append($1) }
+
+        self.init(
+            id: "custom-\(index)-\(slug)",
+            name: trimmedName,
+            description: string("description") ?? "",
+            colourSpace: string("colour_space")?.lowercased() ?? "rgb",
+            patchCount: int("patch_count") ?? 800,
+            whitePatches: int("white_patches") ?? 4,
+            blackPatches: int("black_patches") ?? 4,
+            greySteps: int("grey_steps"),
+            singleChannelSteps: int("single_channel_steps"),
+            neutralSteps: int("neutral_steps"),
+            neutralConcentration: double("neutral_concentration"),
+            preconditioningProfile: string("preconditioning_profile"),
+            ofpsHighQuality: bool("ofps_high_quality"),
+            ofpsAdaptation: double("ofps_adaptation"),
+            fullSpreadAlgorithm: string("full_spread_algorithm"),
+            totalInkLimit: int("total_ink_limit"),
+            darkEmphasis: double("dark_emphasis"),
+            devicePower: double("device_power"),
+            instrument: string("instrument") ?? "i1",
+            pageSize: string("page_size") ?? "A4",
+            bitDepth: int("bit_depth") ?? 8,
+            dpi: int("dpi") ?? 300,
+            randomSeed: int("random_seed"),
+            noRandomize: bool("no_randomize"),
+            calibrationFile: string("calibration_file"),
+            applyCalibration: bool("apply_calibration"),
+            colprofAlgorithm: string("colprof_algorithm"),
+            colprofQuality: string("colprof_quality"),
+            colprofIntent: string("colprof_intent"),
+            colprofFwa: string("colprof_fwa"),
+            colprofIlluminant: string("colprof_illuminant"),
+            colprofObserver: string("colprof_observer"),
+            colprofInputViewingCond: string("colprof_input_viewing_cond"),
+            colprofOutputViewingCond: string("colprof_output_viewing_cond")
+        )
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Settings/PresetCatalog.swift

@@ -0,0 +1,118 @@
+import Foundation
+
+/// Built-in presets shipped with the app (docs/22 §Built-in presets).
+/// All four: instrument `i1`, FWA `D50`, random seed `1`,
+/// `no_randomize == false`, colprof algorithm `l`.
+///
+/// Built-ins cannot be deleted; custom presets overlay by `id`.
+public enum PresetCatalog {
+
+    /// `preset-std-rgb` — Standard RGB Photo (800 patches).
+    public static let standardRGB = ProfilingPreset(
+        id: "preset-std-rgb",
+        name: "Standard RGB Photo (800 patches)",
+        description: "Everyday RGB driver printing — 800 patches on A4 at 300 dpi.",
+        colourSpace: "rgb",
+        patchCount: 800,
+        whitePatches: 4,
+        blackPatches: 4,
+        instrument: "i1",
+        pageSize: "A4",
+        bitDepth: 8,
+        dpi: 300,
+        randomSeed: 1,
+        noRandomize: false,
+        colprofAlgorithm: "l",
+        colprofQuality: "m",
+        colprofFwa: "D50"
+    )
+
+    /// `preset-hq-cmyk` — High-Gamut CMYK Proofing (1500 patches).
+    public static let highQualityCMYK = ProfilingPreset(
+        id: "preset-hq-cmyk",
+        name: "High-Gamut CMYK Proofing (1500 patches)",
+        description: "RIP-driven CMYK output — 1500 patches on A3, 16-bit, 320% ink limit.",
+        colourSpace: "cmyk",
+        patchCount: 1500,
+        whitePatches: 4,
+        blackPatches: 8,
+        totalInkLimit: 320,
+        instrument: "i1",
+        pageSize: "A3",
+        bitDepth: 16,
+        dpi: 300,
+        randomSeed: 1,
+        noRandomize: false,
+        colprofAlgorithm: "l",
+        colprofQuality: "h",
+        colprofFwa: "D50"
+    )
+
+    /// `preset-draft-rgb` — Fast RGB Draft (400 patches, **150 dpi**).
+    public static let draftRGB = ProfilingPreset(
+        id: "preset-draft-rgb",
+        name: "Fast RGB Draft (400 patches)",
+        description: "Quick sanity check — 400 patches on A4 at 150 dpi.",
+        colourSpace: "rgb",
+        patchCount: 400,
+        whitePatches: 4,
+        blackPatches: 4,
+        instrument: "i1",
+        pageSize: "A4",
+        bitDepth: 8,
+        dpi: 150,
+        randomSeed: 1,
+        noRandomize: false,
+        colprofAlgorithm: "l",
+        colprofQuality: "l",
+        colprofFwa: "D50"
+    )
+
+    /// `preset-ultra-rgb` — Ultra Precision RGB (2500 patches, `-G`).
+    public static let ultraRGB = ProfilingPreset(
+        id: "preset-ultra-rgb",
+        name: "Ultra Precision RGB (2500 patches)",
+        description: "Maximum coverage — 2500 patches on A3, 16-bit, OFPS high quality.",
+        colourSpace: "rgb",
+        patchCount: 2500,
+        whitePatches: 6,
+        blackPatches: 6,
+        ofpsHighQuality: true,
+        instrument: "i1",
+        pageSize: "A3",
+        bitDepth: 16,
+        dpi: 300,
+        randomSeed: 1,
+        noRandomize: false,
+        colprofAlgorithm: "l",
+        colprofQuality: "u",
+        colprofFwa: "D50"
+    )
+
+    public static let builtIns: [ProfilingPreset] = [
+        standardRGB, highQualityCMYK, draftRGB, ultraRGB,
+    ]
+
+    public static let builtInIDs: Set<String> = Set(builtIns.map(\.id))
+
+    public static func isBuiltIn(_ id: String) -> Bool {
+        builtInIDs.contains(id)
+    }
+
+    /// Built-ins plus custom presets, with custom entries overlaying by
+    /// `id` (a custom preset with a built-in id replaces that entry in
+    /// place — the built-in is still not deletable).
+    public static func all(custom: [ProfilingPreset]) -> [ProfilingPreset] {
+        var result = builtIns
+        var seen = builtInIDs
+        for custom in custom {
+            if let idx = result.firstIndex(where: { $0.id == custom.id }) {
+                result[idx] = custom
+            } else if !seen.contains(custom.id) {
+                result.append(custom)
+                seen.insert(custom.id)
+            }
+        }
+        return result
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Settings/PresetStore.swift

@@ -0,0 +1,98 @@
+import Foundation
+
+/// CRUD + import/export for profiling presets on top of `SettingsStore`
+/// (docs/22 §Built-in presets, issue #11).
+///
+/// - `all()` = built-ins overlaid by custom presets (by `id`).
+/// - Built-ins are never written to `settings.json` and cannot be
+///   deleted or overwritten by `saveCustom` (a custom id that collides
+///   with a built-in still overlays at read time, per spec).
+/// - Import/export is single-preset JSON with schema validation.
+/// - Imported names/descriptions are untrusted: callers must render
+///   them with `Text`, never HTML (#114).
+public final class PresetStore: Sendable {
+
+    public let settingsStore: SettingsStore
+
+    public init(settingsStore: SettingsStore = SettingsStore()) {
+        self.settingsStore = settingsStore
+    }
+
+    /// All presets: built-ins overlaid by customs, catalog order.
+    public func all() -> [ProfilingPreset] {
+        PresetCatalog.all(custom: settingsStore.load().customPresets)
+    }
+
+    /// Custom presets only, as persisted.
+    public func customs() -> [ProfilingPreset] {
+        settingsStore.load().customPresets
+    }
+
+    /// Insert or replace a custom preset (matched by `id`). Throws
+    /// `PresetStoreError.builtIn` when the id belongs to a built-in —
+    /// built-ins are immutable. Validates before persisting.
+    public func saveCustom(_ preset: ProfilingPreset) throws {
+        let validated = try preset.validated()
+        guard !PresetCatalog.isBuiltIn(validated.id) else {
+            throw PresetStoreError.builtInImmutable(validated.id)
+        }
+        var settings = settingsStore.load()
+        if let idx = settings.customPresets.firstIndex(where: { $0.id == validated.id }) {
+            settings.customPresets[idx] = validated
+        } else {
+            settings.customPresets.append(validated)
+        }
+        try settingsStore.save(settings)
+    }
+
+    /// Deletes a custom preset by id. Returns false when the id is a
+    /// built-in (undeletable) or no custom preset with that id exists.
+    @discardableResult
+    public func deleteCustom(id: String) throws -> Bool {
+        guard !PresetCatalog.isBuiltIn(id) else { return false }
+        var settings = settingsStore.load()
+        let before = settings.customPresets.count
+        settings.customPresets.removeAll { $0.id == id }
+        guard settings.customPresets.count != before else { return false }
+        try settingsStore.save(settings)
+        return true
+    }
+
+    /// Single-preset pretty JSON export.
+    public func export(_ preset: ProfilingPreset) throws -> Data {
+        let encoder = JSONEncoder()
+        encoder.outputFormatting = [.prettyPrinted, .sortedKeys]
+        return try encoder.encode(preset)
+    }
+
+    /// Parses + validates a preset from JSON. The preset is assigned a
+    /// fresh custom id when its id is empty or collides with a built-in.
+    /// Does **not** persist — call `saveCustom` to keep it.
+    public func `import`(_ data: Data) throws -> ProfilingPreset {
+        let decoded: ProfilingPreset
+        do {
+            decoded = try JSONDecoder().decode(ProfilingPreset.self, from: data)
+        } catch {
+            throw PresetStoreError.invalidJSON(error.localizedDescription)
+        }
+        var preset = try decoded.validated()
+        if preset.id.isEmpty || PresetCatalog.isBuiltIn(preset.id) {
+            preset.id = "custom-\(UUID().uuidString.lowercased())"
+        }
+        return preset
+    }
+
+    public enum PresetStoreError: LocalizedError, Equatable {
+        case builtInImmutable(String)
+        case invalidJSON(String)
+
+        public var errorDescription: String? {
+            switch self {
+            case .builtInImmutable(let id):
+                return "Built-in preset \"\(id)\" cannot be modified or deleted."
+            case .invalidJSON(let reason):
+                return "Not a valid preset file: \(reason)"
+            }
+        }
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Settings/ProfilingPreset.swift

@@ -0,0 +1,272 @@
+import Foundation
+
+/// A profiling preset: a complete snapshot of the Stage 1/2 form plus
+/// the Stage 4 fields that are stored now and applied in issue 23
+/// (docs/22 §ProfilingPreset).
+///
+/// snake_case keys match the v1 JSON schema so import/export stays
+/// compatible. Identity + Stage 1/2 core fields are required; every
+/// other field is optional-defaulted. Unknown keys are ignored on
+/// decode; missing required fields fail.
+public struct ProfilingPreset: Codable, Equatable, Sendable, Identifiable {
+
+    // Identity
+    public var id: String
+    public var name: String
+    public var description: String
+
+    // Stage 1 (required core)
+    public var colourSpace: String          // "rgb" | "cmyk"
+    public var patchCount: Int
+    public var whitePatches: Int
+    public var blackPatches: Int
+
+    // Stage 1 advanced (optional)
+    public var greySteps: Int?
+    public var singleChannelSteps: Int?
+    public var neutralSteps: Int?
+    public var neutralConcentration: Double?
+    public var preconditioningProfile: String?
+    public var ofpsHighQuality: Bool?
+    public var ofpsAdaptation: Double?
+    /// Stored as the flag letter: "ofps" or "t","r","R","q","Q","i","I".
+    public var fullSpreadAlgorithm: String?
+    public var totalInkLimit: Int?
+    public var darkEmphasis: Double?
+    public var devicePower: Double?
+
+    // Stage 2 (required core)
+    public var instrument: String
+    public var pageSize: String
+    public var bitDepth: Int
+    public var dpi: Int
+    public var randomSeed: Int?
+    public var noRandomize: Bool?
+
+    // Stage 0 / 2 calibration
+    public var calibrationFile: String?
+    public var applyCalibration: Bool?
+
+    // Stage 4 (stored now, applied by issue 23)
+    public var colprofAlgorithm: String?
+    public var colprofQuality: String?
+    public var colprofIntent: String?
+    public var colprofFwa: String?
+    public var colprofIlluminant: String?
+    public var colprofObserver: String?
+    public var colprofInputViewingCond: String?
+    public var colprofOutputViewingCond: String?
+
+    public init(
+        id: String,
+        name: String,
+        description: String = "",
+        colourSpace: String = "rgb",
+        patchCount: Int = 800,
+        whitePatches: Int = 4,
+        blackPatches: Int = 4,
+        greySteps: Int? = nil,
+        singleChannelSteps: Int? = nil,
+        neutralSteps: Int? = nil,
+        neutralConcentration: Double? = nil,
+        preconditioningProfile: String? = nil,
+        ofpsHighQuality: Bool? = nil,
+        ofpsAdaptation: Double? = nil,
+        fullSpreadAlgorithm: String? = nil,
+        totalInkLimit: Int? = nil,
+        darkEmphasis: Double? = nil,
+        devicePower: Double? = nil,
+        instrument: String = "i1",
+        pageSize: String = "A4",
+        bitDepth: Int = 8,
+        dpi: Int = 300,
+        randomSeed: Int? = 1,
+        noRandomize: Bool? = false,
+        calibrationFile: String? = nil,
+        applyCalibration: Bool? = nil,
+        colprofAlgorithm: String? = nil,
+        colprofQuality: String? = nil,
+        colprofIntent: String? = nil,
+        colprofFwa: String? = nil,
+        colprofIlluminant: String? = nil,
+        colprofObserver: String? = nil,
+        colprofInputViewingCond: String? = nil,
+        colprofOutputViewingCond: String? = nil
+    ) {
+        self.id = id
+        self.name = name
+        self.description = description
+        self.colourSpace = colourSpace
+        self.patchCount = patchCount
+        self.whitePatches = whitePatches
+        self.blackPatches = blackPatches
+        self.greySteps = greySteps
+        self.singleChannelSteps = singleChannelSteps
+        self.neutralSteps = neutralSteps
+        self.neutralConcentration = neutralConcentration
+        self.preconditioningProfile = preconditioningProfile
+        self.ofpsHighQuality = ofpsHighQuality
+        self.ofpsAdaptation = ofpsAdaptation
+        self.fullSpreadAlgorithm = fullSpreadAlgorithm
+        self.totalInkLimit = totalInkLimit
+        self.darkEmphasis = darkEmphasis
+        self.devicePower = devicePower
+        self.instrument = instrument
+        self.pageSize = pageSize
+        self.bitDepth = bitDepth
+        self.dpi = dpi
+        self.randomSeed = randomSeed
+        self.noRandomize = noRandomize
+        self.calibrationFile = calibrationFile
+        self.applyCalibration = applyCalibration
+        self.colprofAlgorithm = colprofAlgorithm
+        self.colprofQuality = colprofQuality
+        self.colprofIntent = colprofIntent
+        self.colprofFwa = colprofFwa
+        self.colprofIlluminant = colprofIlluminant
+        self.colprofObserver = colprofObserver
+        self.colprofInputViewingCond = colprofInputViewingCond
+        self.colprofOutputViewingCond = colprofOutputViewingCond
+    }
+
+    enum CodingKeys: String, CodingKey {
+        case id, name, description
+        case colourSpace = "colour_space"
+        case patchCount = "patch_count"
+        case whitePatches = "white_patches"
+        case blackPatches = "black_patches"
+        case greySteps = "grey_steps"
+        case singleChannelSteps = "single_channel_steps"
+        case neutralSteps = "neutral_steps"
+        case neutralConcentration = "neutral_concentration"
+        case preconditioningProfile = "preconditioning_profile"
+        case ofpsHighQuality = "ofps_high_quality"
+        case ofpsAdaptation = "ofps_adaptation"
+        case fullSpreadAlgorithm = "full_spread_algorithm"
+        case totalInkLimit = "total_ink_limit"
+        case darkEmphasis = "dark_emphasis"
+        case devicePower = "device_power"
+        case instrument
+        case pageSize = "page_size"
+        case bitDepth = "bit_depth"
+        case dpi
+        case randomSeed = "random_seed"
+        case noRandomize = "no_randomize"
+        case calibrationFile = "calibration_file"
+        case applyCalibration = "apply_calibration"
+        case colprofAlgorithm = "colprof_algorithm"
+        case colprofQuality = "colprof_quality"
+        case colprofIntent = "colprof_intent"
+        case colprofFwa = "colprof_fwa"
+        case colprofIlluminant = "colprof_illuminant"
+        case colprofObserver = "colprof_observer"
+        case colprofInputViewingCond = "colprof_input_viewing_cond"
+        case colprofOutputViewingCond = "colprof_output_viewing_cond"
+    }
+
+    /// Strict decode: required identity + Stage 1/2 core fields must be
+    /// present; optionals default to nil. Unknown keys are ignored.
+    public init(from decoder: Decoder) throws {
+        let c = try decoder.container(keyedBy: CodingKeys.self)
+        id = try c.decode(String.self, forKey: .id)
+        name = try c.decode(String.self, forKey: .name)
+        description = try c.decodeIfPresent(String.self, forKey: .description) ?? ""
+        colourSpace = try c.decode(String.self, forKey: .colourSpace)
+        patchCount = try c.decode(Int.self, forKey: .patchCount)
+        whitePatches = try c.decode(Int.self, forKey: .whitePatches)
+        blackPatches = try c.decode(Int.self, forKey: .blackPatches)
+        greySteps = try c.decodeIfPresent(Int.self, forKey: .greySteps)
+        singleChannelSteps = try c.decodeIfPresent(Int.self, forKey: .singleChannelSteps)
+        neutralSteps = try c.decodeIfPresent(Int.self, forKey: .neutralSteps)
+        neutralConcentration = try c.decodeIfPresent(Double.self, forKey: .neutralConcentration)
+        preconditioningProfile = try c.decodeIfPresent(String.self, forKey: .preconditioningProfile)
+        ofpsHighQuality = try c.decodeIfPresent(Bool.self, forKey: .ofpsHighQuality)
+        ofpsAdaptation = try c.decodeIfPresent(Double.self, forKey: .ofpsAdaptation)
+        fullSpreadAlgorithm = try c.decodeIfPresent(String.self, forKey: .fullSpreadAlgorithm)
+        totalInkLimit = try c.decodeIfPresent(Int.self, forKey: .totalInkLimit)
+        darkEmphasis = try c.decodeIfPresent(Double.self, forKey: .darkEmphasis)
+        devicePower = try c.decodeIfPresent(Double.self, forKey: .devicePower)
+        instrument = try c.decode(String.self, forKey: .instrument)
+        pageSize = try c.decode(String.self, forKey: .pageSize)
+        bitDepth = try c.decode(Int.self, forKey: .bitDepth)
+        dpi = try c.decode(Int.self, forKey: .dpi)
+        randomSeed = try c.decodeIfPresent(Int.self, forKey: .randomSeed)
+        noRandomize = try c.decodeIfPresent(Bool.self, forKey: .noRandomize)
+        calibrationFile = try c.decodeIfPresent(String.self, forKey: .calibrationFile)
+        applyCalibration = try c.decodeIfPresent(Bool.self, forKey: .applyCalibration)
+        colprofAlgorithm = try c.decodeIfPresent(String.self, forKey: .colprofAlgorithm)
+        colprofQuality = try c.decodeIfPresent(String.self, forKey: .colprofQuality)
+        colprofIntent = try c.decodeIfPresent(String.self, forKey: .colprofIntent)
+        colprofFwa = try c.decodeIfPresent(String.self, forKey: .colprofFwa)
+        colprofIlluminant = try c.decodeIfPresent(String.self, forKey: .colprofIlluminant)
+        colprofObserver = try c.decodeIfPresent(String.self, forKey: .colprofObserver)
+        colprofInputViewingCond = try c.decodeIfPresent(String.self, forKey: .colprofInputViewingCond)
+        colprofOutputViewingCond = try c.decodeIfPresent(String.self, forKey: .colprofOutputViewingCond)
+    }
+
+    // MARK: - Validation (import path)
+
+    public enum ValidationError: LocalizedError, Equatable {
+        case emptyID
+        case emptyName
+        case invalidColourSpace(String)
+        case invalidPatchCount(Int)
+        case invalidBitDepth(Int)
+        case invalidDPI(Int)
+        case emptyPageSize
+        case emptyInstrument
+
+        public var errorDescription: String? {
+            switch self {
+            case .emptyID: return "Preset is missing an id."
+            case .emptyName: return "Preset is missing a name."
+            case .invalidColourSpace(let v):
+                return "colour_space must be \"rgb\" or \"cmyk\", got \"\(v)\"."
+            case .invalidPatchCount(let v):
+                return "patch_count must be positive, got \(v)."
+            case .invalidBitDepth(let v):
+                return "bit_depth must be 8 or 16, got \(v)."
+            case .invalidDPI(let v):
+                return "dpi must be between 72 and 600, got \(v)."
+            case .emptyPageSize: return "page_size is empty."
+            case .emptyInstrument: return "instrument is empty."
+            }
+        }
+    }
+
+    /// Validates the required fields for import / catalog use.
+    /// `colourSpace` is normalized to lowercase before comparison.
+    @discardableResult
+    public func validated() throws -> ProfilingPreset {
+        var p = self
+        p.id = id.trimmingCharacters(in: .whitespacesAndNewlines)
+        p.name = name.trimmingCharacters(in: .whitespacesAndNewlines)
+        p.colourSpace = colourSpace.lowercased()
+        guard !p.id.isEmpty else { throw ValidationError.emptyID }
+        guard !p.name.isEmpty else { throw ValidationError.emptyName }
+        guard p.colourSpace == "rgb" || p.colourSpace == "cmyk" else {
+            throw ValidationError.invalidColourSpace(colourSpace)
+        }
+        guard p.patchCount > 0 else { throw ValidationError.invalidPatchCount(patchCount) }
+        guard p.bitDepth == 8 || p.bitDepth == 16 else {
+            throw ValidationError.invalidBitDepth(bitDepth)
+        }
+        guard (72...600).contains(p.dpi) else { throw ValidationError.invalidDPI(dpi) }
+        guard !p.pageSize.trimmingCharacters(in: .whitespaces).isEmpty else {
+            throw ValidationError.emptyPageSize
+        }
+        guard !p.instrument.trimmingCharacters(in: .whitespaces).isEmpty else {
+            throw ValidationError.emptyInstrument
+        }
+        return p
+    }
+}
+
+/// Per-element non-throwing decode wrapper — one malformed preset entry
+/// must not drop the whole `custom_presets` array during migration.
+struct FailableDecodable<T: Decodable>: Decodable {
+    let value: T?
+    init(from decoder: Decoder) throws {
+        value = try? T(from: decoder)
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Settings/SettingsStore.swift

@@ -0,0 +1,47 @@
+import Foundation
+
+/// Persists `AppSettings` to
+/// `~/Library/Application Support/com.gronod.iccery2/settings.json`
+/// (issue #5 — the v1 path is never read).
+///
+/// Writes are atomic (`AtomicFileWriter`). Invalid/corrupt JSON falls
+/// back to defaults. Saving posts `settingsDidChange` so #20 can
+/// reclassify swatches.
+public final class SettingsStore: Sendable {
+
+    /// Posted on `NotificationCenter.default` after every successful save.
+    public static let settingsDidChange =
+        Notification.Name("com.gronod.iccery2.settingsDidChange")
+
+    public let fileURL: URL
+
+    public init(fileURL: URL = AppPaths.appDataDir.appendingPathComponent("settings.json")) {
+        self.fileURL = fileURL
+    }
+
+    public func load() -> AppSettings {
+        guard let data = try? Data(contentsOf: fileURL),
+              let settings = try? JSONDecoder().decode(AppSettings.self, from: data)
+        else {
+            return .default
+        }
+        return settings
+    }
+
+    /// Validates before persisting — throws `SettingsError` listing
+    /// every violation; nothing is written on failure.
+    public func save(_ settings: AppSettings) throws {
+        let errors = settings.validate()
+        guard errors.isEmpty else {
+            throw SettingsError.validationFailed(errors)
+        }
+        let encoder = JSONEncoder()
+        encoder.outputFormatting = [.prettyPrinted, .sortedKeys]
+        try AtomicFileWriter.write(encoder.encode(settings), to: fileURL)
+        NotificationCenter.default.post(name: Self.settingsDidChange, object: nil)
+    }
+
+    public enum SettingsError: Error, Equatable {
+        case validationFailed([String])
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Wizard/WizardGating.swift

@@ -0,0 +1,59 @@
+import Foundation
+
+/// Artefact-driven stage gating (issue #4, docs/06 §Stages).
+///
+/// Navigation is *disk*, not buttons: a stage unlocks only when its
+/// predecessor artefacts exist. Forward moves are gated; backward is
+/// always allowed. Gating is re-evaluated on window focus and on stage
+/// entry (#151 — files can disappear in Finder).
+public enum WizardGating {
+
+    /// Whether `stage` is reachable given the probed artefacts.
+    ///
+    /// - Stage 0 (calibrate): always — it is out-of-band, not gated.
+    /// - Stage 1: always.
+    /// - Stage 2: `.ti1` exists.
+    /// - Stage 3: `.ti1` **and** `.ti2`.
+    /// - Stage 4: `.ti3` exists (accepted measurement only — a `.ti2`
+    ///   alone never unlocks it; #109/#110).
+    /// - Stage 5: `.ti3` **and** `.icc`/`.icm`.
+    public static func isUnlocked(
+        _ stage: WizardStage,
+        artefacts: StageArtefacts
+    ) -> Bool {
+        switch stage {
+        case .calibrate:     return true
+        case .generate:      return true
+        case .layOutPrint:   return artefacts.stage1Complete
+        case .measure:       return artefacts.stage1Complete && artefacts.stage2Complete
+        case .buildProfile:  return artefacts.stage3Complete
+        case .verifyInstall: return artefacts.stage3Complete && artefacts.stage4Complete
+        }
+    }
+
+    /// Whether `go(to:)` may proceed. Backward moves and the current
+    /// stage are always allowed; forward moves must be unlocked.
+    public static func canNavigate(
+        to target: WizardStage,
+        from current: WizardStage,
+        artefacts: StageArtefacts
+    ) -> Bool {
+        if target == current { return true }
+        if target == .calibrate || current == .calibrate {
+            // Stage 0 is a side-trip, not stepper navigation.
+            return true
+        }
+        if target.rawValue < current.rawValue { return true }
+        return isUnlocked(target, artefacts: artefacts)
+    }
+
+    /// The deepest unlocked stepper stage — used when revalidation
+    /// locks the current stage (#151).
+    public static func deepestUnlocked(artefacts: StageArtefacts) -> WizardStage {
+        for stage in WizardStage.stepperStages.reversed()
+        where isUnlocked(stage, artefacts: artefacts) {
+            return stage
+        }
+        return .generate
+    }
+}

Packages/ICCeryCore/Sources/ICCeryCore/Wizard/WizardState.swift

@@ -0,0 +1,72 @@
+import Foundation
+
+/// Session mode (docs/06 §wizardState). `"calibration"` is set while
+/// Stage 0 is driving a `CAL_` chart through the same pipeline.
+public enum SessionMode: String, Codable, Sendable {
+    case profile
+    case calibration
+}
+
+/// Persisted wizard state (docs/06 §wizardState fields) —
+/// `wizard_state.json` in app data.
+public struct WizardState: Codable, Equatable, Sendable {
+    /// 0–5 (`WizardStage.rawValue`).
+    public var currentStage: Int
+    /// Run name without extension — never invented (#60).
+    public var basename: String
+    /// Working directory for artefacts; empty → `resolveSafeCwd` (#59).
+    public var cwd: String
+    /// Last spooled printer, for calibration drift history.
+    public var printerName: String?
+    public var sessionMode: SessionMode
+    /// May differ from `basename` after a `.ti3` import (#94).
+    public var profileBasename: String?
+
+    public init(
+        currentStage: Int = WizardStage.generate.rawValue,
+        basename: String = "",
+        cwd: String = "",
+        printerName: String? = nil,
+        sessionMode: SessionMode = .profile,
+        profileBasename: String? = nil
+    ) {
+        self.currentStage = currentStage
+        self.basename = basename
+        self.cwd = cwd
+        self.printerName = printerName
+        self.sessionMode = sessionMode
+        self.profileBasename = profileBasename
+    }
+
+    public static let `default` = WizardState()
+
+    /// The stage a saved `currentStage` resolves to, clamped to a valid
+    /// value (corrupt ints fall back to Stage 1).
+    public var stage: WizardStage {
+        WizardStage(rawValue: currentStage) ?? .generate
+    }
+}
+
+/// Atomic JSON persistence for `WizardState` (issue #4).
+public final class WizardStateStore: Sendable {
+    public let fileURL: URL
+
+    public init(
+        fileURL: URL = AppPaths.appDataDir.appendingPathComponent("wizard_state.json")
+    ) {
+        self.fileURL = fileURL
+    }
+
+    public func load() -> WizardState {
+        guard let data = try? Data(contentsOf: fileURL),
+              let state = try? JSONDecoder().decode(WizardState.self, from: data)
+        else { return .default }
+        return state
+    }
+
+    public func save(_ state: WizardState) throws {
+        let encoder = JSONEncoder()
+        encoder.outputFormatting = [.prettyPrinted, .sortedKeys]
+        try AtomicFileWriter.write(encoder.encode(state), to: fileURL)
+    }
+}

Resources/Argyll/mocks/chartread.mock

@@ -0,0 +1,79 @@
+#!/bin/bash
+# Mock chartread for bundled/manual testing.
+# Supports handheld and XY modes. Writes basename.ti3 on 'd'.
+MODE="${MOCK_CHARTREAD_MODE:-strip}"
+BASENAME=""
+
+# Basename is the last non-flag argument.
+for arg in "$@"; do
+  case "$arg" in
+    -*) ;;
+    *) BASENAME="$arg" ;;
+  esac
+done
+
+read_input() {
+  IFS= read -r line || return 1
+}
+
+emit_row() {
+  printf 'ROW_COLORS_JSON: %s\n' "$1"
+}
+
+write_ti3() {
+  if [ -n "$BASENAME" ]; then
+    echo "MOCK_TI3" > "${BASENAME}.ti3"
+  fi
+}
+
+if [ "$MODE" = "xy" ]; then
+  echo "Place instrument on calibration tile and hit [Space] to calibrate."
+  read_input
+  echo "Calibration successful."
+
+  echo "Please place sheet 1 of 1 on the table"
+  echo "hit return to continue, Esc or 'q' to give up"
+  read_input
+
+  echo "locate patch A1 with the sight,"
+  echo "then hit return to continue"
+  read_input
+
+  echo "Reading sheet 1..."
+  emit_row '{"event": "row_complete", "row_id": "A", "row_index": 0, "total_rows": 1, "patch_count": 3, "patches": [{"id": "1", "loc": "A1", "is_pad": false, "device": [0.0, 50.0, 100.0], "expected": {"XYZ": [18.4210, 20.1234, 15.6789], "Lab": [51.98, -8.45, 12.32]}, "measured": {"XYZ": [18.5120, 20.0451, 15.7100], "Lab": [51.89, -8.31, 12.15]}}, {"id": "2", "loc": "A2", "is_pad": false, "device": [10.0, 60.0, 90.0], "expected": {"Lab": [60.0, 10.0, -20.0]}, "measured": {"Lab": [60.1, 10.5, -19.5]}}, {"id": "3", "loc": "A3", "is_pad": true, "device": [100.0, 100.0, 100.0], "measured": {"Lab": [95.0, 0.0, 0.0]}}]}'
+
+  echo "Sheet 1 of 1 read OK"
+  echo "Please remove last sheet from table"
+  echo "'d' if/when done"
+  while read_input; do
+    case "$line" in
+      d*) write_ti3; exit 0 ;;
+      q*) exit 0 ;;
+    esac
+  done
+  exit 0
+fi
+
+# Handheld / strip mode (default)
+echo "Place instrument on calibration tile and hit [Space] to calibrate."
+read_input
+echo "Calibration successful."
+
+echo "Hit [Space] to read strip A"
+read_input
+echo "Reading strip A..."
+emit_row '{"event": "row_complete", "row_id": "A", "row_index": 0, "total_rows": 2, "patch_count": 3, "patches": [{"id": "1", "loc": "A1", "is_pad": false, "device": [0.0, 50.0, 100.0], "expected": {"XYZ": [18.4210, 20.1234, 15.6789], "Lab": [51.98, -8.45, 12.32]}, "measured": {"XYZ": [18.5120, 20.0451, 15.7100], "Lab": [51.89, -8.31, 12.15]}}, {"id": "2", "loc": "A2", "is_pad": false, "device": [10.0, 60.0, 90.0], "expected": {"Lab": [60.0, 10.0, -20.0]}, "measured": {"Lab": [60.1, 10.5, -19.5]}}, {"id": "3", "loc": "A3", "is_pad": true, "device": [100.0, 100.0, 100.0], "measured": {"Lab": [95.0, 0.0, 0.0]}}]}'
+
+echo "Hit [Space] to read strip B"
+read_input
+echo "Reading strip B..."
+emit_row '{"event": "row_complete", "row_id": "B", "row_index": 1, "total_rows": 2, "patch_count": 2, "patches": [{"id": "4", "loc": "B1", "is_pad": false, "device": [100.0, 0.0, 0.0], "expected": {"Lab": [40.0, 40.0, 40.0]}, "measured": {"Lab": [38.0, 41.0, 39.0]}}, {"id": "5", "loc": "B2", "is_pad": false, "device": [0.0, 100.0, 0.0], "expected": {"Lab": [80.0, -50.0, 50.0]}, "measured": {"Lab": [79.0, -49.0, 51.0]}}]}'
+
+echo "'d' if/when done"
+while read_input; do
+  case "$line" in
+    d*) write_ti3; exit 0 ;;
+    q*) exit 0 ;;
+  esac
+done
+exit 0

Resources/Argyll/mocks/colprof.mock

@@ -0,0 +1,20 @@
+#!/bin/bash
+# Mock script for colprof
+# Simulates colprof execution and outputs progress log
+
+basename="$1"
+# Find last argument if -D or other flags are used
+for arg in "$@"; do
+    basename="$arg"
+done
+
+echo "colprof: Starting profile calculation for $basename"
+sleep 1
+echo "Gamut mapping calculation..."
+sleep 1
+echo "Fitting cLUT grid points..."
+sleep 1
+echo "Writing ICC profile $basename.icc..."
+touch "$basename.icc"
+echo "Done."
+exit 0

Resources/Argyll/mocks/profcheck.mock

@@ -0,0 +1,12 @@
+#!/bin/bash
+# Mock script for profcheck
+# Simulates real ArgyllCMS profcheck -v -k -s -u output
+
+echo "profcheck: Checking profile accuracy..."
+echo "No of test patches = 52"
+sleep 1
+cat << 'EOF'
+{"event": "report", "peak_de2000": 2.41, "avg_de2000": 0.85, "rms": 1.02}
+EOF
+echo "Profile check complete, errors(CIEDE2000): max. = 2.41, avg. = 0.85, RMS = 1.02"
+exit 0

Resources/ICCery.entitlements

@@ -4,5 +4,7 @@
 <dict>
 	<!-- App Sandbox intentionally absent: ICCery must spawn Argyll tools,
 	     read/write user-chosen working directories, and talk to lp/CUPS. -->
+	<key>com.apple.security.device.usb</key>
+	<true/>
 </dict>
 </plist>

Sources/ICCery/AppEnvironment.swift

@@ -0,0 +1,124 @@
+import Foundation
+import ICCeryCore
+
+/// App dependency container (docs/02). Production builds resolve the
+/// user's `argyll_binary_dir` override or bundled sidecars; DEBUG UI
+/// tests inject fixture binaries via `ICCERY_ARGYLL_BINARY_DIR` and
+/// redirect `AppPaths` via `ICCERY_TEST_ROOT`, so tests never touch the
+/// developer's settings, wizard state, or real Argyll install.
+struct AppEnvironment: Sendable {
+    let stateStore: WizardStateStore
+    let settingsStore: SettingsStore
+    let presetStore: PresetStore
+    let runner: ArgyllRunner
+    let cupsService: CupsService
+    let historyStore: VerificationHistoryStore
+
+    static func live(
+        environment: [String: String] = ProcessInfo.processInfo.environment
+    ) -> AppEnvironment {
+        let settingsStore = SettingsStore()
+        var overrideDir = settingsStore.load().argyllBinaryDir
+            .map { URL(fileURLWithPath: $0) }
+        var cupsDir = URL(fileURLWithPath: "/usr/bin")
+        #if DEBUG
+        if let dir = environment["ICCERY_ARGYLL_BINARY_DIR"], !dir.isEmpty {
+            overrideDir = URL(fileURLWithPath: dir)
+        }
+        if let dir = environment["ICCERY_CUPS_BIN_DIR"], !dir.isEmpty {
+            cupsDir = URL(fileURLWithPath: dir)
+        }
+        #endif
+        return AppEnvironment(
+            stateStore: WizardStateStore(),
+            settingsStore: settingsStore,
+            presetStore: PresetStore(settingsStore: settingsStore),
+            runner: ArgyllRunner(
+                processManager: .shared,
+                binaryResolver: BinaryResolver(overrideDir: overrideDir)
+            ),
+            cupsService: CupsService(
+                processManager: .shared,
+                binaryDir: cupsDir),
+            historyStore: VerificationHistoryStore()
+        )
+    }
+}
+
+/// DEBUG-only UI-test hooks. When `ICCERY_UI_TESTING=1` the workflow
+/// honours these env-provided paths instead of presenting modal panels
+/// (XCUITest cannot drive NSOpenPanel/NSSavePanel reliably). These are
+/// compiled out of release builds.
+enum UITestHooks {
+    private static var env: [String: String] {
+        ProcessInfo.processInfo.environment
+    }
+
+    static var isEnabled: Bool {
+        #if DEBUG
+        return env["ICCERY_UI_TESTING"] == "1"
+        #else
+        return false
+        #endif
+    }
+
+    /// `select_target_file` result (Stage 1 save picker).
+    static var saveTargetURL: URL? { url("ICCERY_TEST_SAVE_TARGET") }
+    /// `select_existing_target` result (`.ti1`/`.ti2` resume).
+    static var existingTargetURL: URL? { url("ICCERY_TEST_EXISTING_TARGET") }
+    /// `select_directory` result (working-directory browse).
+    static var workDirURL: URL? { url("ICCERY_TEST_WORKDIR") }
+    /// Dataset import file (`.ti3`, `.txt`, `.cgats`, `.csv`).
+    static var datasetImportURL: URL? { url("ICCERY_TEST_DATASET_IMPORT") }
+    /// Preset import file.
+    static var presetImportURL: URL? { url("ICCERY_TEST_PRESET_IMPORT") }
+    /// Preset export destination.
+    static var presetExportURL: URL? { url("ICCERY_TEST_PRESET_EXPORT") }
+
+    // MARK: - Print panel / CUPS stubs (issue 13/17)
+
+    /// Directory of mock `lp`/`lpstat`/`lpoptions` fixture scripts —
+    /// `CupsService.binaryDir` under UI tests.
+    static var cupsBinaryDir: URL? { url("ICCERY_CUPS_BIN_DIR") }
+
+    /// Path the mock `lp` script appends its argv to, for assertions.
+    static var lpArgvOutURL: URL? { url("ICCERY_TEST_LP_ARGV") }
+
+    /// Whether the `NSPrintPanel` should be stubbed under UI testing —
+    /// separate from the stub's *result* so "cancel" (`nil`) does not
+    /// fall through to the real modal.
+    static var printPanelStubbed: Bool { isEnabled }
+
+    /// Canned `NSPrintPanel` outcome — XCUITest cannot drive the
+    /// system modal. `ICCERY_TEST_PRINT_PANEL`:
+    /// - `cancel` (or unset while testing) → user cancelled → `nil`
+    /// - `ok` → `PrintPropertiesResult` with
+    ///   `ICCERY_TEST_PANEL_OPTIONS` (captured `k=v` string) and
+    ///   `ICCERY_TEST_PANEL_PRINTER` (selected queue; default = the
+    ///   queue the panel was opened for).
+    static func printPanelResult(forQueue queue: String) -> PrintPropertiesResult? {
+        switch env["ICCERY_TEST_PRINT_PANEL"] {
+        case "ok":
+            let options = env["ICCERY_TEST_PANEL_OPTIONS"].flatMap {
+                $0.isEmpty ? nil : $0
+            }
+            return PrintPropertiesResult(
+                selectedPrinter: env["ICCERY_TEST_PANEL_PRINTER"].flatMap {
+                    $0.isEmpty ? nil : $0
+                } ?? queue,
+                options: PrintOptions(
+                    mediaType: options.flatMap {
+                        CupsParsers.extractMediaType(fromOptionsString: $0)
+                    },
+                    ppdUncorrectedPassthrough: true,
+                    cupsOptions: options))
+        default:
+            return nil
+        }
+    }
+
+    private static func url(_ key: String) -> URL? {
+        guard let raw = env[key], !raw.isEmpty else { return nil }
+        return URL(fileURLWithPath: raw)
+    }
+}

Sources/ICCery/DriftChartView.swift

@@ -0,0 +1,121 @@
+import SwiftUI
+import ICCeryCore
+
+/// Minimal line chart for drift history without depending on the
+/// `Charts` framework link. Renders avg/max series with shaded quality
+/// bands.
+struct DriftChartView: View {
+    let records: [VerificationRecord]
+
+    var body: some View {
+        GeometryReader { geometry in
+            let width = geometry.size.width
+            let height = geometry.size.height
+
+            ZStack(alignment: .topLeading) {
+                if let (_, _, _, maxV) = scales(in: height) {
+                    // Quality bands — bottom (red, > 3.5) drawn first, then
+                    // orange, yellow, green so the upper-most bands overlay.
+                    band(from: 3.5, to: maxV, color: .red.opacity(0.12), height: height, maxValue: maxV)
+                    band(from: 2.0, to: 3.5, color: .orange.opacity(0.12), height: height, maxValue: maxV)
+                    band(from: 1.0, to: 2.0, color: .yellow.opacity(0.12), height: height, maxValue: maxV)
+                    band(from: 0.0, to: 1.0, color: .green.opacity(0.12), height: height, maxValue: maxV)
+                }
+
+                if !records.isEmpty, let (minT, maxT, minV, maxV) = scales(in: height) {
+                    // Average ΔE series
+                    Path { path in
+                        for (index, record) in records.enumerated() {
+                            let pt = point(
+                                for: record,
+                                minTime: minT,
+                                maxTime: maxT,
+                                minValue: minV,
+                                maxValue: maxV,
+                                width: width,
+                                height: height,
+                                keyPath: \.avgDE
+                            )
+                            if index == 0 {
+                                path.move(to: pt)
+                            } else {
+                                path.addLine(to: pt)
+                            }
+                        }
+                    }
+                    .stroke(Color.blue, lineWidth: 2)
+                    .accessibilityIdentifier("driftAvgSeries")
+
+                    // Max ΔE series
+                    Path { path in
+                        for (index, record) in records.enumerated() {
+                            let pt = point(
+                                for: record,
+                                minTime: minT,
+                                maxTime: maxT,
+                                minValue: minV,
+                                maxValue: maxV,
+                                width: width,
+                                height: height,
+                                keyPath: \.maxDE
+                            )
+                            if index == 0 {
+                                path.move(to: pt)
+                            } else {
+                                path.addLine(to: pt)
+                            }
+                        }
+                    }
+                    .stroke(Color.orange, lineWidth: 2)
+                    .accessibilityIdentifier("driftMaxSeries")
+                } else {
+                    Text("No data")
+                        .font(.caption)
+                        .foregroundStyle(.secondary)
+                        .frame(maxWidth: .infinity, maxHeight: .infinity)
+                }
+            }
+        }
+    }
+
+    private func band(
+        from lower: Double,
+        to upper: Double,
+        color: Color,
+        height: CGFloat,
+        maxValue: Double
+    ) -> some View {
+        let yTop = valueY(lower, minValue: 0, maxValue: maxValue, height: height)
+        let yBottom = valueY(upper, minValue: 0, maxValue: maxValue, height: height)
+        return color
+            .frame(height: yBottom - yTop)
+            .offset(y: yTop)
+    }
+
+    private func scales(in height: CGFloat) -> (Date, Date, Double, Double)? {
+        guard let minT = records.first?.timestamp, let maxT = records.last?.timestamp else { return nil }
+        let maxV = max(records.map { max($0.avgDE, $0.maxDE) }.max() ?? 5.0, 5.0)
+        return (minT, maxT, 0.0, maxV)
+    }
+
+    private func point(
+        for record: VerificationRecord,
+        minTime: Date,
+        maxTime: Date,
+        minValue: Double,
+        maxValue: Double,
+        width: CGFloat,
+        height: CGFloat,
+        keyPath: KeyPath<VerificationRecord, Double>
+    ) -> CGPoint {
+        let timeSpan = max(1, maxTime.timeIntervalSince(minTime))
+        let x = width * CGFloat(record.timestamp.timeIntervalSince(minTime) / timeSpan)
+        let y = valueY(record[keyPath: keyPath], minValue: minValue, maxValue: maxValue, height: height)
+        return CGPoint(x: x, y: y)
+    }
+
+    private func valueY(_ value: Double, minValue: Double, maxValue: Double, height: CGFloat) -> CGFloat {
+        let valueSpan = max(1, maxValue - minValue)
+        return height - height * CGFloat((value - minValue) / valueSpan)
+    }
+}

Sources/ICCery/FileDialogService.swift

@@ -0,0 +1,129 @@
+import AppKit
+import UniformTypeIdentifiers
+
+/// Dedicated NSOpenPanel / NSSavePanel wrappers (issue #6) — one method
+/// per purpose, matching the v1 `select_*` commands (docs/21 §Dialogs).
+/// No call site shares a generic picker (#103/#210/#211).
+@MainActor
+final class FileDialogService {
+
+    static let shared = FileDialogService()
+    private init() {}
+
+    // MARK: - selectDirectory
+
+    /// `#btnBrowse` — working directory for Argyll artefacts.
+    /// Defaults to Documents (docs/06 §Empty cwd).
+    func selectDirectory(startingAt start: URL? = nil) -> URL? {
+        let panel = NSOpenPanel()
+        panel.canChooseDirectories = true
+        panel.canChooseFiles = false
+        panel.allowsMultipleSelection = false
+        panel.directoryURL = start
+            ?? FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first
+        panel.prompt = "Choose"
+        return run(panel)
+    }
+
+    // MARK: - Dedicated open pickers
+
+    /// `selectTargetFile` — **save** panel for the new `.ti1` target.
+    func selectTargetFile(startingAt start: URL? = nil) -> URL? {
+        let panel = NSSavePanel()
+        panel.nameFieldStringValue = "target.ti1"
+        panel.allowedContentTypes = utTypes(["ti1"])
+        panel.allowsOtherFileTypes = false
+        panel.directoryURL = start
+        panel.message = "Choose the .ti1 target file to create"
+        return run(panel)
+    }
+
+    /// `selectExistingTarget` — open `.ti1`/`.ti2` (docs/06 §Resume, #140).
+    func selectExistingTarget(startingAt start: URL? = nil) -> URL? {
+        open(extensions: ["ti1", "ti2"], startingAt: start,
+             message: "Open an existing target (.ti1 or .ti2)")
+    }
+
+    /// `selectProfileFile` — `.icc`/`.icm`/`.mpp` only — **never** `.ti*`
+    /// (#172: the profile filter must not accept datasets).
+    func selectProfileFile(startingAt start: URL? = nil) -> URL? {
+        open(extensions: ["icc", "icm", "mpp"], startingAt: start,
+             message: "Choose an ICC/ICM profile or measurement preconditioning file")
+    }
+
+    /// `selectSpectrumFile` — `.sp` illuminant spectrum (colprof -i).
+    func selectSpectrumFile(startingAt start: URL? = nil) -> URL? {
+        open(extensions: ["sp"], startingAt: start,
+             message: "Choose a custom illuminant spectrum (.sp)")
+    }
+
+    /// `selectDatasetFile` — open a measured dataset (`.ti3`, `.txt`,
+    /// `.cgats`, `.csv`). Always an *open* dialog, never save (#211).
+    func selectDatasetFile(startingAt start: URL? = nil) -> URL? {
+        open(extensions: ["ti3", "txt", "cgats", "csv"], startingAt: start,
+             message: "Import a measured dataset")
+    }
+
+    /// `selectCsvSavePath` — verification-history CSV export.
+    func selectCsvSavePath(startingAt start: URL? = nil) -> URL? {
+        let panel = NSSavePanel()
+        panel.nameFieldStringValue = "verification-history.csv"
+        panel.allowedContentTypes = utTypes(["csv"])
+        panel.allowsOtherFileTypes = false
+        panel.directoryURL = start
+        return run(panel)
+    }
+
+    /// `selectCalFile` — `.cal` calibration curves.
+    func selectCalFile(startingAt start: URL? = nil) -> URL? {
+        open(extensions: ["cal"], startingAt: start,
+             message: "Choose a calibration file (.cal)")
+    }
+
+    /// `btnImportPreset` — open a `.json` preset file.
+    func selectPresetFile(startingAt start: URL? = nil) -> URL? {
+        open(extensions: ["json"], startingAt: start,
+             message: "Import a profiling preset (.json)")
+    }
+
+    /// `btnExportActivePreset` — save a `.json` preset file.
+    func selectPresetSavePath(name: String, startingAt start: URL? = nil) -> URL? {
+        let panel = NSSavePanel()
+        panel.nameFieldStringValue = "\(name).json"
+        panel.allowedContentTypes = utTypes(["json"])
+        panel.allowsOtherFileTypes = false
+        panel.directoryURL = start
+        panel.message = "Export this preset as JSON"
+        return run(panel)
+    }
+
+    // MARK: - Internals (private — not a shared public picker API)
+
+    private func open(
+        extensions: [String],
+        startingAt start: URL?,
+        message: String?
+    ) -> URL? {
+        let panel = NSOpenPanel()
+        panel.canChooseDirectories = false
+        panel.canChooseFiles = true
+        panel.allowsMultipleSelection = false
+        panel.allowedContentTypes = utTypes(extensions)
+        panel.allowsOtherFileTypes = true
+        panel.directoryURL = start
+        if let message { panel.message = message }
+        return run(panel)
+    }
+
+    private func utTypes(_ extensions: [String]) -> [UTType] {
+        extensions.compactMap { UTType(filenameExtension: $0) }
+    }
+
+    private func run(_ panel: NSOpenPanel) -> URL? {
+        panel.runModal() == .OK ? panel.url : nil
+    }
+
+    private func run(_ panel: NSSavePanel) -> URL? {
+        panel.runModal() == .OK ? panel.url : nil
+    }
+}

Sources/ICCery/ICCeryApp.swift

@@ -1,15 +1,25 @@
 import AppKit
+import ICCeryCore
 import SwiftUI
 
 @main
 struct ICCeryApp: App {
     @NSApplicationDelegateAdaptor(AppDelegate.self) private var appDelegate
-    @State private var model = WizardViewModel()
+    @State private var workflow: TargetWorkflowViewModel
+
+    init() {
+        let environment = AppEnvironment.live()
+        _workflow = State(initialValue: TargetWorkflowViewModel(environment: environment))
+        try? AppPaths.ensureDirectories()
+        // Log level is runtime state — apply persisted settings at
+        // startup (#158); the Settings sheet re-applies on save.
+        LogSink.shared.applySettings(environment.settingsStore.load())
+    }
 
     var body: some Scene {
         // Single fixed window (docs/21 §Shell: 1280×800, min 1100×700).
         Window("ICCery", id: "main") {
-            RootView(model: model)
+            RootView(workflow: workflow)
                 .frame(minWidth: 1100, minHeight: 700)
                 .preferredColorScheme(.dark)
         }
@@ -19,15 +29,24 @@ struct ICCeryApp: App {
     }
 }
 
-/// AppDelegate: quit when the single window closes, and give later
-/// milestones a hook to `killAll` Argyll children before teardown
-/// (#147/#149 — wired once ProcessManager exists in #2).
+/// AppDelegate: quit when the single window closes, and `killAll` Argyll
+/// children before teardown (#147/#149). Termination is deferred until
+/// `killAll` has signaled every child so `chartread` can park an XY head
+/// when the UI already sent `q\n`.
 final class AppDelegate: NSObject, NSApplicationDelegate {
+    private var terminationRequested = false
+
     func applicationShouldTerminateAfterLastWindowClosed(_ sender: NSApplication) -> Bool {
         true
     }
 
-    func applicationWillTerminate(_ notification: Notification) {
-        // Issue #2+: ProcessManager.shared.killAll()
+    func applicationShouldTerminate(_ sender: NSApplication) -> NSApplication.TerminateReply {
+        guard !terminationRequested else { return .terminateNow }
+        terminationRequested = true
+        Task {
+            await ProcessManager.shared.killAll()
+            NSApplication.shared.reply(toApplicationShouldTerminate: true)
+        }
+        return .terminateLater
     }
 }

Sources/ICCery/MeasurementWorkflowViewModel.swift

@@ -0,0 +1,462 @@
+import Foundation
+import Observation
+import SwiftUI
+import ICCeryCore
+
+/// A single evaluated swatch for the live grid.
+struct Swatch: Sendable, Equatable, Identifiable {
+    let rowId: String
+    let loc: String
+    let isPad: Bool
+    let intended: DisplayRGB
+    let measured: DisplayRGB
+    let deltaE: Double?
+    let classification: SwatchClassification
+
+    var id: String { "\(rowId)\(loc)" }
+}
+
+/// A row of swatches in display order.
+struct SwatchRow: Sendable, Equatable, Identifiable {
+    let index: Int
+    let rowId: String
+    let patches: [Swatch]
+
+    var id: String { rowId }
+}
+
+/// Stage of the XY-table badge bar.
+enum XYStep: Equatable, Sendable {
+    case place, align, scan, remove
+}
+
+/// Stage 3 workflow state and interaction (issues #18–#22).
+@MainActor
+@Observable
+final class MeasurementWorkflowViewModel {
+
+    // MARK: - Authorities
+
+    let wizard: WizardViewModel
+    let environment: AppEnvironment
+
+    // MARK: - Settings-driven thresholds
+
+    private(set) var goodMax: Double = 2.0
+    private(set) var warningMax: Double = 5.0
+    private(set) var enableLEDs: Bool = false
+
+    // MARK: - Instrument detection
+
+    var instruments: [InstrumentDevice] = []
+    var selectedInstrument: InstrumentSelection = .auto
+    var isDetecting = false
+    var detectionError: String?
+
+    // MARK: - Chartread session
+
+    var isChartreadRunning = false
+    var chartreadState: ChartreadState = .idle
+    var currentPrompt: String?
+    var requestedWarningKey: String?
+    var chartreadLog: [String] = []
+    var rows: [ChartreadRow] = []
+    var swatchRows: [SwatchRow] = []
+    var showRemoveSheetNotice = false
+    var lastError: String?
+    private var chartreadTask: Task<Void, Never>?
+
+    // MARK: - Averaging
+
+    var passSnapshots: [URL] = []
+    var isFinishing = false
+    var finishNotice: String?
+    var finishNoticeIsError = false
+    var resumedFromTi2 = false
+
+    init(wizard: WizardViewModel, environment: AppEnvironment) {
+        self.wizard = wizard
+        self.environment = environment
+        loadSettings()
+        discoverPassSnapshots()
+    }
+
+    // MARK: - Derived state
+
+    var basename: String { wizard.basename }
+    var workingDirectory: URL? { wizard.effectiveWorkingDirectory }
+
+    var canDetect: Bool { !isDetecting }
+
+    var canStartRead: Bool {
+        !basename.isEmpty && workingDirectory != nil && !isChartreadRunning
+    }
+
+    var canMeasureAnotherSheet: Bool {
+        isFinished && !passSnapshots.isEmpty
+    }
+
+    var canFinish: Bool {
+        isFinished && !passSnapshots.isEmpty
+    }
+
+    var isFinished: Bool {
+        chartreadState == .allStripsRead || chartreadState == .finished
+    }
+
+    var xyStep: XYStep {
+        if showRemoveSheetNotice { return .remove }
+        switch chartreadState {
+        case .tablePlaceSheet:
+            return .place
+        case .tableAlign:
+            return .align
+        case .reading, .awaitingStrip:
+            return .scan
+        default:
+            return .place
+        }
+    }
+
+    var hasCanonicalTi3: Bool {
+        guard let cwd = workingDirectory else { return false }
+        let url = cwd.appendingPathComponent("\(basename).ti3")
+        return FileManager.default.fileExists(atPath: url.path)
+    }
+
+    // MARK: - Settings
+
+    func loadSettings() {
+        let settings = environment.settingsStore.load()
+        goodMax = settings.deltaEGoodMax
+        warningMax = settings.deltaEWarningMax
+        enableLEDs = settings.enableI1Pro2Leds
+    }
+
+    // MARK: - Instrument detection
+
+    func detectInstruments() {
+        guard !isDetecting else { return }
+        isDetecting = true
+        detectionError = nil
+
+        Task { @MainActor [weak self] in
+            guard let self else { return }
+            do {
+                let devices = try await self.environment.runner.detectInstruments()
+                self.instruments = devices
+                if case .device(let selected) = self.selectedInstrument,
+                   !devices.contains(where: { $0.port == selected.port }) {
+                    self.selectedInstrument = .auto
+                }
+            } catch {
+                self.detectionError = error.localizedDescription
+            }
+            self.isDetecting = false
+        }
+    }
+
+    // MARK: - Chartread lifecycle
+
+    func startRead() {
+        guard canStartRead, let cwd = workingDirectory else { return }
+        let config = buildChartreadConfig(cwd: cwd)
+        startChartread(config: config)
+    }
+
+    func measureAnotherSheet() {
+        guard let cwd = workingDirectory, isFinished else { return }
+        let config = buildChartreadConfig(cwd: cwd)
+        startChartread(config: config)
+    }
+
+    private func buildChartreadConfig(cwd: URL) -> ChartreadConfig {
+        ChartreadConfig(
+            basename: basename,
+            workingDirectory: cwd,
+            selectedPort: selectedInstrument.chartreadPort,
+            enableLEDs: enableLEDs,
+            isXY: selectedInstrument.isXY
+        )
+    }
+
+    private func startChartread(config: ChartreadConfig) {
+        guard !isChartreadRunning else { return }
+
+        isChartreadRunning = true
+        chartreadState = .idle
+        currentPrompt = nil
+        lastError = nil
+        chartreadLog.removeAll()
+
+        // Optional: reset rows when starting a fresh first pass.
+        if passSnapshots.isEmpty {
+            rows.removeAll()
+            swatchRows.removeAll()
+        }
+
+        let stream = environment.runner.runChartread(config: config)
+
+        chartreadTask = Task { @MainActor [weak self] in
+            guard let self else { return }
+            for await event in stream {
+                self.handle(event: event)
+            }
+            self.isChartreadRunning = false
+        }
+    }
+
+    private func handle(event: ChartreadEvent) {
+        switch event {
+        case .prompt(let result):
+            chartreadState = result.state
+            currentPrompt = promptText(for: result)
+            requestedWarningKey = result.requestedWarningKey
+            showRemoveSheetNotice = result.isRemoveSheetNotice
+
+        case .row(let row):
+            upsert(row: row)
+            if row.isFinalRow {
+                chartreadState = .allStripsRead
+            }
+
+        case .log(let batch):
+            chartreadLog.append(contentsOf: batch)
+
+        case .removeSheetNotice:
+            showRemoveSheetNotice = true
+
+        case .exit(let code):
+            if code != 0 {
+                lastError = "chartread exited with code \(code)"
+            }
+
+        case .completed(let canonicalURL):
+            chartreadState = .finished
+            completePass(canonicalURL: canonicalURL)
+
+        case .failed(let error):
+            lastError = error.localizedDescription
+            chartreadState = .error
+            isChartreadRunning = false
+        }
+    }
+
+    private func promptText(for result: ChartreadClassifyResult) -> String {
+        switch result.state {
+        case .calibrating:
+            return "Place instrument on calibration tile and press Calibrate."
+        case .awaitingStrip:
+            return "Press a key to read the next strip."
+        case .allStripsRead:
+            return "All strips read. Press Done & Save when ready."
+        case .warning:
+            if let key = result.requestedWarningKey {
+                return "Warning — press '\(key.uppercased())' to continue."
+            }
+            return "Warning — press Continue."
+        case .promptContinue:
+            return "Press Continue."
+        case .tablePlaceSheet:
+            if let n = result.sheetNumber, let t = result.sheetTotal {
+                return "Place sheet \(n) of \(t) on the table."
+            }
+            return "Place the sheet on the table."
+        case .tableAlign:
+            if let patch = result.alignmentPatch {
+                return "Locate patch \(patch) with the sight, then continue."
+            }
+            return "Align the fiducial, then continue."
+        case .reading:
+            return "Reading..."
+        case .error:
+            return "Read error — you can Retry or Cancel."
+        case .finished:
+            return "Measurement saved."
+        case .idle:
+            return "Press Start to begin reading."
+        }
+    }
+
+    // MARK: - User actions
+
+    func calibrate() {
+        send(.trigger)
+    }
+
+    func accept() {
+        if let key = requestedWarningKey {
+            send(.customKey(key))
+            requestedWarningKey = nil
+        } else {
+            send(.accept)
+        }
+    }
+
+    func retry() {
+        send(.trigger)
+    }
+
+    func doneAndSave() {
+        send(.done)
+    }
+
+    func cancelRead() {
+        environment.runner.cancelChartread(basename: basename, isXY: selectedInstrument.isXY)
+        chartreadTask?.cancel()
+        isChartreadRunning = false
+        chartreadState = .idle
+        currentPrompt = nil
+        requestedWarningKey = nil
+        showRemoveSheetNotice = false
+    }
+
+    func sendWarningKey(_ key: String) {
+        send(.customKey(key))
+    }
+
+    private func send(_ input: ChartreadInput) {
+        Task { @MainActor [weak self] in
+            guard let self, self.isChartreadRunning else { return }
+            try? await self.environment.runner.sendChartreadInput(basename: self.basename, input: input)
+        }
+    }
+
+    // MARK: - Rows and swatches
+
+    private func upsert(row: ChartreadRow) {
+        if let index = rows.firstIndex(where: { $0.rowIndex == row.rowIndex }) {
+            rows[index] = row
+        } else {
+            rows.append(row)
+        }
+        rows.sort { $0.rowIndex < $1.rowIndex }
+        recomputeSwatches()
+    }
+
+    func recomputeSwatches() {
+        var displayRows: [SwatchRow] = []
+        for (rowIndex, row) in rows.enumerated() {
+            var swatches: [Swatch] = []
+            for patch in row.patches {
+                let skip = shouldSkipPad(patch)
+                if skip { continue }
+
+                let eval = ColorDifference.evaluate(
+                    patch: patch,
+                    goodMax: goodMax,
+                    warningMax: warningMax
+                )
+                if let eval {
+                    swatches.append(Swatch(
+                        rowId: row.rowId,
+                        loc: patch.loc,
+                        isPad: patch.isPad,
+                        intended: eval.intended,
+                        measured: eval.measured,
+                        deltaE: eval.deltaE,
+                        classification: eval.classification
+                    ))
+                }
+            }
+            if !swatches.isEmpty {
+                displayRows.append(SwatchRow(index: rowIndex, rowId: row.rowId, patches: swatches))
+            }
+        }
+        swatchRows = displayRows
+    }
+
+    private func shouldSkipPad(_ patch: ChartreadPatch) -> Bool {
+        guard patch.isPad else { return false }
+        let measuredEmpty = patch.measured.xyz == nil && patch.measured.lab == nil
+        let deviceAllZero = patch.device.allSatisfy { $0 == 0 }
+        return measuredEmpty && deviceAllZero
+    }
+
+    // MARK: - Pass management
+
+    private func completePass(canonicalURL: URL) {
+        guard let cwd = workingDirectory else { return }
+        do {
+            _ = try MeasurementArtefacts.snapshotPass(basename: basename, cwd: cwd)
+            discoverPassSnapshots()
+            wizard.refreshGating()
+        } catch {
+            lastError = "Could not snapshot pass: \(error.localizedDescription)"
+        }
+    }
+
+    func discoverPassSnapshots() {
+        guard let cwd = workingDirectory else {
+            passSnapshots = []
+            return
+        }
+        passSnapshots = MeasurementArtefacts.passSnapshots(basename: basename, cwd: cwd)
+    }
+
+    // MARK: - Finish / Average
+
+    func finishAndAverage() {
+        guard !isFinishing, let cwd = workingDirectory, !passSnapshots.isEmpty else { return }
+        isFinishing = true
+        finishNotice = nil
+        finishNoticeIsError = false
+
+        Task { @MainActor [weak self] in
+            guard let self else { return }
+            do {
+                let canonical: URL
+                if self.passSnapshots.count == 1, let pass = self.passSnapshots.first {
+                    canonical = try MeasurementArtefacts.promotePass(
+                        pass: pass,
+                        basename: self.basename,
+                        cwd: cwd
+                    )
+                } else {
+                    let config = AverageConfig(
+                        workingDirectory: cwd,
+                        basename: self.basename,
+                        passFiles: self.passSnapshots
+                    )
+                    canonical = try await self.environment.runner.runAverage(
+                        config: config,
+                        onLogBatch: { [weak self] batch in
+                            Task { @MainActor [weak self] in
+                                self?.chartreadLog.append(contentsOf: batch)
+                            }
+                        }
+                    )
+                }
+                self.discoverPassSnapshots()
+                self.wizard.refreshGating()
+                if self.wizard.isUnlocked(.buildProfile) {
+                    self.wizard.go(to: .buildProfile)
+                } else {
+                    self.finishNotice = "Finished: \(canonical.lastPathComponent) ready."
+                }
+            } catch {
+                // Fallback to pass 1 promotion if averaging failed.
+                if let pass = self.passSnapshots.first {
+                    do {
+                        _ = try MeasurementArtefacts.promotePass(
+                            pass: pass,
+                            basename: self.basename,
+                            cwd: cwd
+                        )
+                        self.discoverPassSnapshots()
+                        self.wizard.refreshGating()
+                        self.finishNotice = "Averaging failed — promoted first pass."
+                        self.finishNoticeIsError = true
+                    } catch {
+                        self.finishNotice = "Finish failed: \(error.localizedDescription)"
+                        self.finishNoticeIsError = true
+                    }
+                } else {
+                    self.finishNotice = "Finish failed: \(error.localizedDescription)"
+                    self.finishNoticeIsError = true
+                }
+            }
+            self.isFinishing = false
+        }
+    }
+}

Sources/ICCery/NoticeBanner.swift

@@ -42,6 +42,8 @@ struct NoticeBanner: View {
                 .font(.callout)
                 .foregroundStyle(Theme.text)
                 .lineLimit(3)
+                .accessibilityIdentifier("noticeText")
+                .accessibilityValue(notice.text)
             Spacer()
             Button(action: onClose) {
                 Image(systemName: "xmark")

Sources/ICCery/PresetDialogs.swift

@@ -0,0 +1,92 @@
+import SwiftUI
+import ICCeryCore
+
+/// `#savePresetDialog` — save the live Stage 1/2 form as a custom
+/// preset (issue #11). Names/descriptions render via `Text` only (#114).
+struct SavePresetDialog: View {
+    @Bindable var workflow: TargetWorkflowViewModel
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: 14) {
+            Text("Save Preset").font(.title3).foregroundStyle(Theme.text)
+            TextField("Name", text: $workflow.savePresetName)
+                .textFieldStyle(.roundedBorder)
+                .accessibilityIdentifier("savePresetName")
+            TextField("Description (optional)", text: $workflow.savePresetDesc)
+                .textFieldStyle(.roundedBorder)
+                .accessibilityIdentifier("savePresetDesc")
+            HStack {
+                Spacer()
+                Button("Cancel") { workflow.showingSavePreset = false }
+                    .accessibilityIdentifier("btnCloseSavePresetDialog")
+                Button("Save") { workflow.saveCurrentAsPreset() }
+                    .accessibilityIdentifier("btnConfirmSavePreset")
+                    .disabled(workflow.savePresetName
+                        .trimmingCharacters(in: .whitespaces).isEmpty)
+            }
+        }
+        .padding(20)
+        .frame(width: 380)
+        .background(Theme.background)
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("savePresetDialog")
+    }
+}
+
+/// `#managePresetsDialog` — list, delete (custom only), import, export.
+struct ManagePresetsDialog: View {
+    @Bindable var workflow: TargetWorkflowViewModel
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            Text("Manage Presets").font(.title3).foregroundStyle(Theme.text)
+            List {
+                ForEach(workflow.presets) { preset in
+                    HStack {
+                        VStack(alignment: .leading, spacing: 2) {
+                            Text(preset.name).foregroundStyle(Theme.text)
+                            if !preset.description.isEmpty {
+                                Text(preset.description)
+                                    .font(.caption).foregroundStyle(.secondary)
+                            }
+                        }
+                        Spacer()
+                        if PresetCatalog.isBuiltIn(preset.id) {
+                            Text("Built-in")
+                                .font(.caption).foregroundStyle(.secondary)
+                        } else {
+                            Button("Export") { workflow.exportPreset(preset) }
+                                .accessibilityIdentifier(
+                                    "btnExportPreset-\(preset.id)")
+                            Button("Delete", role: .destructive) {
+                                workflow.deletePreset(preset)
+                            }
+                            .accessibilityIdentifier("btnDeletePreset-\(preset.id)")
+                        }
+                    }
+                    .accessibilityElement(children: .contain)
+                    .accessibilityIdentifier("presetRow-\(preset.id)")
+                }
+            }
+            .accessibilityIdentifier("managePresetsList")
+            .frame(minHeight: 240)
+            HStack {
+                Button("Import…") { workflow.importPreset() }
+                    .accessibilityIdentifier("btnImportPreset")
+                if let selected = workflow.selectedPreset,
+                   !PresetCatalog.isBuiltIn(selected.id) {
+                    Button("Export Active") { workflow.exportPreset(selected) }
+                        .accessibilityIdentifier("btnExportActivePreset")
+                }
+                Spacer()
+                Button("Close") { workflow.showingManagePresets = false }
+                    .accessibilityIdentifier("btnCloseManagePresetsDialog")
+            }
+        }
+        .padding(20)
+        .frame(width: 480)
+        .background(Theme.background)
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("managePresetsDialog")
+    }
+}

Sources/ICCery/Print/ColorSyncSuppressor.swift

@@ -0,0 +1,171 @@
+import AppKit
+import ApplicationServices
+import ICCeryCore
+
+/// Private Print Manager SPI: `(PMPrintSession, CFStringRef) -> OSStatus`.
+/// The second argument is the mode string — never integer `1` (#188).
+typealias ColorMatchingModeFunction =
+    @convention(c) (PMPrintSession, CFString) -> OSStatus
+
+/// `PMPrintSettingsToOptions` — public symbol, resolved via dlsym so a
+/// missing SDK declaration can't break the build.
+typealias PrintSettingsToOptionsFunction =
+    @convention(c) (PMPrintSettings, UnsafeMutablePointer<UnsafeMutablePointer<CChar>?>) -> OSStatus
+
+/// The six-layer unmanaged-printing engine (issue 14, docs/11):
+///
+/// ① session binding — done by `PrintPanelService` before calling us.
+/// ② private SPI `PMSessionSetColorMatchingMode{Lock,,NoLock}` —
+///    resolved by `dlsym(RTLD_DEFAULT,…)`; first `(symbol, mode)`
+///    returning `0` wins.
+/// ③ `PMPrintSettingsSetValue` both `AP_ColorMatchingMode` and
+///    `AP.ColorMatchingMode` = `AP_ApplicationColorMatching`, locked.
+/// ④ driver "no colour adjustment" pre-select from `lpoptions -l`
+///    keys, unlocked (`detectDriverColorBypass`).
+/// ⑤ mirror ③+④ into `NSPrintInfo.printSettings` so the PDE sees them.
+/// ⑥ after "Use Settings": `PMPrintSettingsToOptions` →
+///    `CupsOptionsFilter` → captured `cupsOptions` + `mediaType`.
+///
+/// All layers degrade gracefully — a missing symbol or non-zero status
+/// is logged and the next layer still runs.
+@MainActor
+struct ColorSyncSuppressor {
+
+    /// Injected for tests: symbol → function. Default resolves via
+    /// `dlsym(RTLD_DEFAULT, …)`.
+    typealias ModeResolver = (String) -> ColorMatchingModeFunction?
+    typealias OptionsResolver = () -> PrintSettingsToOptionsFunction?
+
+    var modeResolver: ModeResolver = Self.dlsymMode
+    var optionsResolver: OptionsResolver = Self.dlsymOptions
+    var log: (String) -> Void = { AppLogger.shared.log(.info, $0) }
+
+    // MARK: - Layer ② SPI
+
+    /// Walk `ColorMatchingAttempts.attempts` (Lock → plain → NoLock ×
+    /// `AP_ApplicationColorMatching` → `ApplicationColorMatching`); the
+    /// first call returning `0` wins. `false` when nothing worked.
+    @discardableResult
+    func applySPIMode(to session: PMPrintSession) -> Bool {
+        for attempt in ColorMatchingAttempts.attempts {
+            guard let function = modeResolver(attempt.symbol) else {
+                continue
+            }
+            let status = function(session, attempt.mode as CFString)
+            if status == 0 {
+                log("ColorSync: \(attempt.symbol) accepted "
+                    + "\(attempt.mode)")
+                return true
+            }
+        }
+        log("ColorSync: no PMSessionSetColorMatchingMode* accepted a "
+            + "mode — falling back to PMPrintSettingsSetValue")
+        return false
+    }
+
+    // MARK: - Layer ③ locked AP_* keys
+
+    /// `PMPrintSettingsSetValue` both key spellings, locked.
+    @discardableResult
+    func applyLockedKeys(to settings: PMPrintSettings) -> Int {
+        var applied = 0
+        for key in ColorMatchingAttempts.printSettingsKeys {
+            let status = PMPrintSettingsSetValue(
+                settings,
+                key as CFString,
+                ColorMatchingAttempts.applicationMatchingValue as CFString,
+                true)
+            if status == 0 { applied += 1 }
+        }
+        if applied == 0 {
+            log("ColorSync: PMPrintSettingsSetValue could not lock "
+                + "AP_ColorMatchingMode")
+        }
+        return applied
+    }
+
+    // MARK: - Layer ④ driver bypass
+
+    /// Pre-select the driver "no colour adjustment" option, unlocked —
+    /// the PDE may override it. Returns the `(key, value)` applied.
+    @discardableResult
+    func applyDriverBypass(
+        to settings: PMPrintSettings,
+        optionKeys: Set<String>
+    ) -> (key: String, value: String)? {
+        guard let bypass = CupsParsers.detectDriverColorBypass(
+            optionKeys: optionKeys)
+        else { return nil }
+        let status = PMPrintSettingsSetValue(
+            settings,
+            bypass.key as CFString,
+            bypass.value as CFString,
+            false)
+        if status != 0 {
+            log("ColorSync: driver bypass \(bypass.key)=\(bypass.value) "
+                + "rejected (\(status))")
+            return nil
+        }
+        return bypass
+    }
+
+    // MARK: - Layer ⑤ NSPrintInfo mirror
+
+    /// Mirror the applied keys into `printSettings` so the PDE pick
+    /// sees them.
+    func mirror(
+        into printInfo: NSPrintInfo,
+        driverBypass: (key: String, value: String)?
+    ) {
+        let settings = printInfo.printSettings
+        for key in ColorMatchingAttempts.printSettingsKeys {
+            settings[key as NSString] = ColorMatchingAttempts.applicationMatchingValue as NSString
+        }
+        if let driverBypass {
+            settings[driverBypass.key as NSString] = driverBypass.value as NSString
+        }
+    }
+
+    // MARK: - Layer ⑥ capture
+
+    /// `PMPrintSettingsToOptions` → filter → `(cupsOptions, mediaType)`.
+    /// The malloc'd C string is freed after copying.
+    func captureOptions(
+        from settings: PMPrintSettings
+    ) -> (cupsOptions: String?, mediaType: String?) {
+        guard let toOptions = optionsResolver() else {
+            log("ColorSync: PMPrintSettingsToOptions unavailable — "
+                + "panel options not captured")
+            return (nil, nil)
+        }
+        var raw: UnsafeMutablePointer<CChar>?
+        guard toOptions(settings, &raw) == 0, let raw else {
+            return (nil, nil)
+        }
+        defer { free(raw) }
+        let unfiltered = String(cString: raw)
+        let filtered = CupsOptionsFilter.filter(unfiltered)
+        return (
+            filtered.isEmpty ? nil : filtered,
+            CupsParsers.extractMediaType(fromOptionsString: unfiltered)
+        )
+    }
+
+    // MARK: - dlsym
+
+    private static func dlsymMode(_ name: String) -> ColorMatchingModeFunction? {
+        guard let symbol = dlsym(Self.rtldDefault, name) else { return nil }
+        return unsafeBitCast(symbol, to: ColorMatchingModeFunction.self)
+    }
+
+    private static func dlsymOptions() -> PrintSettingsToOptionsFunction? {
+        guard let symbol = dlsym(Self.rtldDefault, "PMPrintSettingsToOptions")
+        else { return nil }
+        return unsafeBitCast(symbol, to: PrintSettingsToOptionsFunction.self)
+    }
+
+    /// `RTLD_DEFAULT` — `UnsafeMutableRawPointer(bitPattern: -2)`.
+    private static var rtldDefault: UnsafeMutableRawPointer? {
+        UnsafeMutableRawPointer(bitPattern: -2)
+    }
+}

Sources/ICCery/Print/PrintPanelService.swift

@@ -0,0 +1,186 @@
+import AppKit
+import ApplicationServices
+import ICCeryCore
+
+/// Errors raised while preparing the bound print panel.
+enum PrintPanelError: LocalizedError {
+    case sessionBindingFailed(OSStatus)
+    case noPrinterFound(String)
+
+    var errorDescription: String? {
+        switch self {
+        case .sessionBindingFailed(let status):
+            return "Could not bind the print session to the queue (OSStatus \(status))."
+        case .noPrinterFound(let name):
+            return "No printer found for '\(name)'."
+        }
+    }
+}
+
+/// Preferences → native `NSPrintPanel` bound to the selected CUPS
+/// queue (issue 13, docs/11).
+///
+/// This is a **settings-capture** dialog — the default button is
+/// "Use Settings", never "Print". It is never System Settings, the
+/// CUPS web UI, or an `NSWorkspace` open (#188). Cancel returns `nil`
+/// and is not an error.
+///
+/// Binding: `PMPrinterCreateFromPrinterID(CUPS queue id)` →
+/// `PMSessionSetCurrentPMPrinter` → session default settings/page
+/// format. `PMPrinter` is `PMRelease`d on every path. Fallback when PM
+/// binding fails: `NSPrinter(name: displayName)` (the `printer-info`
+/// label) → `printInfo.printer`.
+@MainActor
+struct PrintPanelService {
+
+    /// The suppression engine — injectable for tests.
+    var suppressor = ColorSyncSuppressor()
+
+    /// Resolves the display name (off-panel `lpoptions` fetch) and runs
+    /// the modal panel. Returns `nil` when the user cancels.
+    func showProperties(
+        queue: String,
+        displayName: String?,
+        cupsService: CupsService
+    ) async throws -> PrintPropertiesResult? {
+        #if DEBUG
+        if UITestHooks.printPanelStubbed {
+            return UITestHooks.printPanelResult(forQueue: queue)
+        }
+        #endif
+        // `??` rhs is a non-async @autoclosure — fetch first.
+        let fetched = try? await cupsService.displayName(for: queue)
+        let display = displayName ?? fetched
+        // Layer ④ needs the queue's option keys (lpoptions -l) to pick
+        // the driver colour-bypass before the panel opens.
+        let optionKeys = (try? await cupsService.optionKeys(for: queue))
+            ?? []
+        return try runNativePanel(
+            queue: queue, displayName: display, optionKeys: optionKeys)
+    }
+
+    // MARK: - Panel
+
+    private func runNativePanel(
+        queue: String,
+        displayName: String?,
+        optionKeys: Set<String>
+    ) throws -> PrintPropertiesResult? {
+        let printInfo = NSPrintInfo()
+        var pmPrinter: PMPrinter?
+        var boundViaPM = false
+
+        // ① Bind the session to the selected CUPS queue (docs/11).
+        if let printer = PMPrinterCreateFromPrinterID(queue as CFString) {
+            pmPrinter = printer
+            let session = unsafeBitCast(
+                printInfo.pmPrintSession(), to: PMPrintSession.self)
+            let settings = unsafeBitCast(
+                printInfo.pmPrintSettings(), to: PMPrintSettings.self)
+            let pageFormat = unsafeBitCast(
+                printInfo.pmPageFormat(), to: PMPageFormat.self)
+
+            let status = PMSessionSetCurrentPMPrinter(session, printer)
+            if status != 0 {
+                PMRelease(Self.pmObject(printer))
+                throw PrintPanelError.sessionBindingFailed(status)
+            }
+            // Warn-only: defaults keep the panel consistent with the
+            // queue but are not fatal when they fail.
+            _ = PMSessionDefaultPrintSettings(session, settings)
+            _ = PMSessionDefaultPageFormat(session, pageFormat)
+            boundViaPM = true
+        } else {
+            // Fallback: NSPrinter by display name (docs/11 §binding).
+            guard let displayName,
+                  let nsPrinter = NSPrinter(name: displayName)
+            else {
+                throw PrintPanelError.noPrinterFound(
+                    displayName ?? queue)
+            }
+            printInfo.printer = nsPrinter
+            printInfo.setUpPrintOperationDefaultValues()
+        }
+        defer {
+            if let printer = pmPrinter {
+                PMRelease(Self.pmObject(printer))
+            }
+        }
+
+        // ②–⑤ ColourSync suppression — only on the PM path: the SPI
+        // and PMPrintSettingsSetValue need a session with a current
+        // printer to attach to.
+        var settings = unsafeBitCast(
+            printInfo.pmPrintSettings(), to: PMPrintSettings.self)
+        var driverBypass: (key: String, value: String)?
+        if boundViaPM {
+            let session = unsafeBitCast(
+                printInfo.pmPrintSession(), to: PMPrintSession.self)
+            suppressor.applySPIMode(to: session)                    // ②
+            suppressor.applyLockedKeys(to: settings)                // ③
+            driverBypass = suppressor.applyDriverBypass(            // ④
+                to: settings, optionKeys: optionKeys)
+            suppressor.mirror(into: printInfo, driverBypass: driverBypass) // ⑤
+        }
+
+        let panel = NSPrintPanel()
+        panel.options = [
+            .showsCopies, .showsPageRange, .showsPaperSize,
+            .showsOrientation, .showsScaling, .showsPrintSelection,
+            .showsPageSetupAccessory, .showsPreview,
+        ]
+        panel.setDefaultButtonTitle("Use Settings")
+
+        let response = panel.runModal(with: printInfo)
+        guard response == NSApplication.ModalResponse.OK.rawValue else {
+            return nil
+        }
+
+        // ⑥ Capture the user's choices — filtered replay options plus
+        // the media type they picked. Re-fetch the settings handle so
+        // we read back what the modal wrote.
+        var cupsOptions: String?
+        var mediaType: String?
+        if boundViaPM {
+            settings = unsafeBitCast(
+                printInfo.pmPrintSettings(), to: PMPrintSettings.self)
+            let captured = suppressor.captureOptions(from: settings)
+            cupsOptions = captured.cupsOptions
+            mediaType = captured.mediaType
+        }
+        return PrintPropertiesResult(
+            selectedPrinter: boundViaPM
+                ? Self.currentPrinterID(
+                    session: unsafeBitCast(
+                        printInfo.pmPrintSession(), to: PMPrintSession.self),
+                    fallback: queue)
+                : nil,
+            options: PrintOptions(
+                mediaType: mediaType,
+                ppdUncorrectedPassthrough: true,
+                cupsOptions: cupsOptions))
+    }
+
+    // MARK: - PM helpers
+
+    /// `PMPrinter` → `PMObject` for `PMRelease` — the Carbon API wants
+    /// `UnsafeRawPointer`, Swift imports `PMPrinter` as `OpaquePointer`.
+    static func pmObject(_ printer: PMPrinter) -> PMObject {
+        unsafeBitCast(printer, to: PMObject.self)
+    }
+
+    /// `PMSessionGetCurrentPrinter` → `PMPrinterGetID` → String.
+    private static func currentPrinterID(
+        session: PMPrintSession,
+        fallback: String
+    ) -> String {
+        var current: PMPrinter?
+        guard PMSessionGetCurrentPrinter(session, &current) == 0,
+              let printer = current
+        else { return fallback }
+        defer { PMRelease(pmObject(printer)) }
+        guard let id = PMPrinterGetID(printer)
+        else { return fallback }
+        return id.takeUnretainedValue() as String
+    }
+}

Sources/ICCery/ProfileWorkflowViewModel.swift

@@ -0,0 +1,506 @@
+import Foundation
+import Observation
+import SwiftUI
+import ICCeryCore
+
+/// User-facing FWA selection for the Stage 4 form.
+enum ColprofFwaSelection: String, CaseIterable, Sendable, Equatable {
+    case none = "none"
+    case empty = ""
+    case D50 = "D50"
+    case D65 = "D65"
+    case custom = "custom"
+
+    var displayName: String {
+        switch self {
+        case .none: return "None"
+        case .empty: return "Bare (-f)"
+        case .D50: return "D50"
+        case .D65: return "D65"
+        case .custom: return "Custom .sp"
+        }
+    }
+}
+
+/// Stage 4/5 workflow: build a profile, verify it, track drift, and install.
+@MainActor
+@Observable
+final class ProfileWorkflowViewModel {
+
+    let wizard: WizardViewModel
+    let environment: AppEnvironment
+    private let fileDialogs = FileDialogService.shared
+
+    // MARK: - Stage 4 form
+
+    var algorithm: String = "l"      // l | x | X | m
+    var quality: String = "m"        // l | m | h | u
+    var intent: String = ""          // usually empty at Stage 4
+    var fwaSelection: ColprofFwaSelection = .none
+    var fwaCustomPath: String = ""
+    var illuminant: String = ""
+    var observer: String = ""
+    var inputViewingCond: String = ""
+    var outputViewingCond: String = ""
+    var profileDescription: String = ""
+    var copyright: String = ""
+
+    // MARK: - Run state
+
+    var isColprofRunning = false
+    var colprofLog: [String] = []
+    var colprofProgress: String?
+    var lastError: String?
+    var createdProfileURL: URL?
+
+    // MARK: - Stage 4/5 calibration (issue #24)
+
+    var applyCalibration = false
+    var calibrationFile: String = ""
+
+    // MARK: - Stage 5 verification (issue #25)
+
+    var profcheckReport: ProfcheckReport?
+    var profcheckWarning: String?
+    var isProfcheckRunning = false
+
+    // MARK: - History / drift (issue #26)
+
+    var verificationHistory: [VerificationRecord] = []
+    var driftPrinterFilter: String? = nil
+    var driftAlert: String?
+    var isHistoryStoreError: String?
+
+    // MARK: - Install (issue #27)
+
+    var installResult: InstallProfileResult?
+    var showingInstallCollision = false
+    var installCollisionMessage: String = ""
+    var pendingInstallOptions: InstallProfileOptions?
+
+    init(wizard: WizardViewModel, environment: AppEnvironment) {
+        self.wizard = wizard
+        self.environment = environment
+        restoreCreatedProfileURL()
+    }
+
+    /// Restores `createdProfileURL` from the wizard artefacts or by probing
+    /// the working directory for an existing `.icc`/`.icm` (#52).
+    func restoreCreatedProfileURL() {
+        let cwd = wizard.effectiveWorkingDirectory ?? PathSecurity.resolveSafeCwd(nil)
+        createdProfileURL = wizard.artefacts.profilePath
+            ?? ArtefactProbe.resolveProfile(basename: wizard.basename, cwd: cwd)
+    }
+
+    // MARK: - Derived
+
+    var canCreateProfile: Bool {
+        !wizard.basename.isEmpty && wizard.effectiveWorkingDirectory != nil && !isColprofRunning
+    }
+
+    var canVerify: Bool {
+        createdProfileURL != nil && !isProfcheckRunning
+    }
+
+    var fwaValue: String? {
+        switch fwaSelection {
+        case .none: return nil
+        case .empty: return ""
+        case .D50: return "D50"
+        case .D65: return "D65"
+        case .custom: return fwaCustomPath
+        }
+    }
+
+    // MARK: - Preset application
+
+    func applyPreset(_ preset: ProfilingPreset?) {
+        guard let preset else { return }
+        algorithm = preset.colprofAlgorithm ?? "l"
+        quality = preset.colprofQuality ?? "m"
+        intent = preset.colprofIntent ?? ""
+
+        if let fwa = preset.colprofFwa {
+            switch fwa.lowercased() {
+            case "none": fwaSelection = .none
+            case "": fwaSelection = .empty
+            case "d50": fwaSelection = .D50
+            case "d65": fwaSelection = .D65
+            default:
+                fwaSelection = .custom
+                fwaCustomPath = fwa
+            }
+        }
+
+        illuminant = preset.colprofIlluminant ?? ""
+        observer = preset.colprofObserver ?? ""
+        inputViewingCond = preset.colprofInputViewingCond ?? ""
+        outputViewingCond = preset.colprofOutputViewingCond ?? ""
+    }
+
+    /// Stage 4 form values for saving into a custom preset.
+    func presetSnapshot() -> (
+        algorithm: String,
+        quality: String,
+        intent: String?,
+        fwa: String?,
+        illuminant: String?,
+        observer: String?,
+        inputViewingCond: String?,
+        outputViewingCond: String?
+    ) {
+        (
+            algorithm: algorithm,
+            quality: quality,
+            intent: intent.isEmpty ? nil : intent,
+            fwa: fwaValue,
+            illuminant: illuminant.isEmpty ? nil : illuminant,
+            observer: observer.isEmpty ? nil : observer,
+            inputViewingCond: inputViewingCond.isEmpty ? nil : inputViewingCond,
+            outputViewingCond: outputViewingCond.isEmpty ? nil : outputViewingCond
+        )
+    }
+
+    // MARK: - Stage 4: build profile
+
+    func buildColprofConfig() -> ColprofConfig {
+        let description = profileDescription.isEmpty ? wizard.basename : profileDescription
+        return ColprofConfig(
+            algorithm: algorithm,
+            quality: quality,
+            intent: intent.isEmpty ? nil : intent,
+            fwa: fwaValue,
+            illuminant: illuminant.isEmpty ? nil : illuminant,
+            observer: observer.isEmpty ? nil : observer,
+            inputViewingCond: inputViewingCond.isEmpty ? nil : inputViewingCond,
+            outputViewingCond: outputViewingCond.isEmpty ? nil : outputViewingCond,
+            description: description,
+            copyright: copyright.isEmpty ? nil : copyright,
+            basename: wizard.basename,
+            workingDirectory: wizard.effectiveWorkingDirectory
+        )
+    }
+
+    func createProfile() {
+        guard canCreateProfile, let _ = wizard.effectiveWorkingDirectory else { return }
+        let config = buildColprofConfig()
+
+        isColprofRunning = true
+        colprofLog = []
+        colprofProgress = nil
+        lastError = nil
+        createdProfileURL = nil
+
+        let runner = environment.runner
+        Task { @MainActor [weak self] in
+            guard let self else { return }
+            defer { self.isColprofRunning = false }
+
+            do {
+                let url = try await runner.runColprof(config: config) { [weak self] batch in
+                    Task { @MainActor [weak self] in
+                        guard let self else { return }
+                        self.colprofLog.append(contentsOf: batch)
+                        if let last = batch.last {
+                            let progress = ColprofProgressClassifier.classify(line: last)
+                            self.updateProgress(progress)
+                        }
+                    }
+                }
+
+                var finalProfileURL = url
+
+                if self.applyCalibration, !self.calibrationFile.isEmpty {
+                    let applyConfig = ApplycalConfig(
+                        calibrationPath: self.calibrationFile,
+                        inputProfileURL: url
+                    )
+                    assert(!applyConfig.unapply, "applycal unapply is not supported in v2.0")
+                    finalProfileURL = try await runner.runApplycal(config: applyConfig)
+                    self.colprofLog.append("Calibration embedded: \(self.calibrationFile)")
+                }
+
+                // Gamut extraction is best-effort for Stage 5 / M6 viewer.
+                do {
+                    let gamConfig = IccgamutConfig(profileURL: finalProfileURL)
+                    _ = try await runner.runIccgamut(config: gamConfig) { [weak self] batch in
+                        Task { @MainActor [weak self] in
+                            self?.colprofLog.append(contentsOf: batch)
+                        }
+                    }
+                    self.colprofLog.append("Gamut mesh extracted.")
+                } catch {
+                    self.wizard.showNotice(
+                        "Gamut extraction skipped: \(error.localizedDescription)",
+                        kind: .info
+                    )
+                }
+
+                self.createdProfileURL = finalProfileURL
+                self.wizard.refreshGating()
+                self.wizard.showNotice("Profile created: \(finalProfileURL.lastPathComponent)")
+                self.wizard.go(to: .verifyInstall)
+            } catch {
+                self.lastError = error.localizedDescription
+                self.wizard.showNotice(
+                    "Profile creation failed: \(error.localizedDescription)",
+                    kind: .error
+                )
+            }
+        }
+    }
+
+    private func updateProgress(_ progress: ColprofProgress) {
+        switch progress {
+        case .gamutMapping:
+            colprofProgress = "Gamut mapping calculation…"
+        case .fittingClut:
+            colprofProgress = "Fitting cLUT grid points…"
+        case .writingIcc:
+            colprofProgress = "Writing ICC profile…"
+        case .unknown:
+            break
+        }
+    }
+
+    // MARK: - Stage 5: verify profile
+
+    var knownPrinters: [String] {
+        var names = Set<String>()
+        for record in verificationHistory {
+            if record.printerName.isEmpty {
+                names.insert("Unknown")
+            } else {
+                names.insert(record.printerName)
+            }
+        }
+        return Array(names).sorted()
+    }
+
+    func loadHistory() {
+        Task { @MainActor [weak self] in
+            guard let self else { return }
+            do {
+                self.verificationHistory = try await self.environment.historyStore.load()
+                self.driftAlert = DriftAlert.compute(from: self.filteredHistory)
+            } catch {
+                self.isHistoryStoreError = error.localizedDescription
+                self.wizard.showNotice(
+                    "Could not load verification history: \(error.localizedDescription)",
+                    kind: .error
+                )
+            }
+        }
+    }
+
+    var filteredHistory: [VerificationRecord] {
+        guard let filter = driftPrinterFilter, !filter.isEmpty else {
+            return verificationHistory
+        }
+        return verificationHistory.filter { $0.printerName == filter }
+    }
+
+    func verifyProfile() {
+        guard canVerify,
+              let cwd = wizard.effectiveWorkingDirectory,
+              let profileURL = createdProfileURL else { return }
+
+        let ti3URL = ArtefactProbe.artefact(wizard.basename, "ti3", cwd)
+        let config = ProfcheckConfig(ti3URL: ti3URL, iccURL: profileURL)
+
+        isProfcheckRunning = true
+        profcheckReport = nil
+        profcheckWarning = nil
+
+        let runner = environment.runner
+        Task { @MainActor [weak self] in
+            guard let self else { return }
+            defer { self.isProfcheckRunning = false }
+
+            do {
+                let report = try await runner.runProfcheck(config: config) { [weak self] batch in
+                    Task { @MainActor [weak self] in
+                        self?.colprofLog.append(contentsOf: batch)
+                    }
+                }
+                self.profcheckReport = report
+                if let record = self.makeVerificationRecord(from: report) {
+                    let updated = try await self.environment.historyStore.append(record)
+                    self.verificationHistory = updated
+                    self.driftAlert = DriftAlert.compute(from: self.filteredHistory)
+                }
+            } catch let error as ArgyllRunnerError where error == .profcheckUnparseable {
+                self.profcheckWarning = "profcheck output could not be parsed."
+                self.profcheckReport = ProfcheckReport(warning: self.profcheckWarning)
+            } catch {
+                self.profcheckWarning = error.localizedDescription
+                self.profcheckReport = ProfcheckReport(warning: self.profcheckWarning)
+                self.wizard.showNotice(
+                    "Verification failed: \(error.localizedDescription)",
+                    kind: .error
+                )
+            }
+        }
+    }
+
+    func makeVerificationRecord(from report: ProfcheckReport) -> VerificationRecord? {
+        guard let avg = report.avgDE,
+              let max = report.maxDE,
+              let rms = report.rmsDE,
+              let status = report.status else { return nil }
+
+        let timestamp = Date()
+        let id = "vr-\(Int(timestamp.timeIntervalSince1970))-\(Self.nextSeq())"
+        let printerName = wizard.printerName?.isEmpty == false ? wizard.printerName! : "Unknown"
+        return VerificationRecord(
+            id: id,
+            profileName: createdProfileURL?.lastPathComponent ?? wizard.basename,
+            printerName: printerName,
+            avgDE: avg,
+            maxDE: max,
+            rmsDE: rms,
+            patchCount: report.patchCount ?? 0,
+            status: status,
+            timestamp: timestamp
+        )
+    }
+
+    private static func nextSeq() -> Int {
+        Int.random(in: 0..<1_000_000)
+    }
+
+    func clearHistory() {
+        Task { @MainActor [weak self] in
+            guard let self else { return }
+            do {
+                try await self.environment.historyStore.clear()
+                self.verificationHistory = []
+                self.driftAlert = nil
+            } catch {
+                self.wizard.showNotice(
+                    "Could not clear history: \(error.localizedDescription)",
+                    kind: .error
+                )
+            }
+        }
+    }
+
+    // MARK: - Profile install
+
+    func beginInstallProfile() {
+        guard let sourceURL = createdProfileURL,
+              let _ = wizard.effectiveWorkingDirectory else { return }
+
+        let settings = environment.settingsStore.load()
+        let preferSystem = settings.defaultInstallLocation == .system
+        let options = InstallProfileOptions(
+            forceOverwrite: !settings.askBeforeOverwriteProfile,
+            preferSystem: preferSystem,
+            collisionPolicy: .overwrite,
+            openColorPanel: settings.openColorPanelAfterInstall
+        )
+
+        do {
+            let config = InstallProfileConfig(sourceURL: sourceURL, options: options)
+            let destURL = try ProfileInstaller.resolveDestinationURL(for: config)
+            let collision = FileManager.default.fileExists(atPath: destURL.path)
+
+            if collision && settings.askBeforeOverwriteProfile {
+                pendingInstallOptions = options
+                installCollisionMessage = "A profile named \(destURL.lastPathComponent) already exists."
+                showingInstallCollision = true
+                return
+            }
+
+            runInstall(sourceURL: sourceURL, options: options)
+        } catch {
+            wizard.showNotice(
+                "Install failed: \(error.localizedDescription)",
+                kind: .error
+            )
+        }
+    }
+
+    func resolveInstallCollision(policy: ProfileCollisionPolicy) {
+        showingInstallCollision = false
+        guard let sourceURL = createdProfileURL,
+              var options = pendingInstallOptions else { return }
+
+        if policy == .cancel {
+            installResult = InstallProfileResult(
+                destPath: "",
+                registered: false,
+                overwritten: false,
+                renamed: false,
+                openedPanel: false,
+                message: "Install cancelled."
+            )
+            return
+        }
+
+        options.collisionPolicy = policy
+        if policy == .overwrite {
+            options.forceOverwrite = true
+        }
+        runInstall(sourceURL: sourceURL, options: options)
+    }
+
+    private func runInstall(sourceURL: URL, options: InstallProfileOptions) {
+        let config = InstallProfileConfig(sourceURL: sourceURL, options: options)
+        Task(priority: .userInitiated) { [weak self] in
+            do {
+                let result = try ProfileInstaller.install(config: config)
+                await MainActor.run { [weak self] in
+                    self?.installResult = result
+                    self?.wizard.showNotice(result.message)
+                }
+            } catch {
+                await MainActor.run { [weak self] in
+                    self?.wizard.showNotice(
+                        "Install failed: \(error.localizedDescription)",
+                        kind: .error
+                    )
+                }
+            }
+        }
+    }
+
+    func exportHistory() {
+        guard let url = fileDialogs.selectCsvSavePath() else { return }
+        Task { @MainActor [weak self] in
+            guard let self else { return }
+            let csv = await self.environment.historyStore.exportCSV()
+            do {
+                try csv.write(to: url, atomically: true, encoding: .utf8)
+                self.wizard.showNotice("History exported: \(url.lastPathComponent)")
+            } catch {
+                self.wizard.showNotice(
+                    "Export failed: \(error.localizedDescription)",
+                    kind: .error
+                )
+            }
+        }
+    }
+
+    // MARK: - File pickers
+
+    func browseForSpectrumFile() {
+        let start = wizard.effectiveWorkingDirectory
+        let url = UITestHooks.isEnabled
+            ? nil
+            : fileDialogs.selectSpectrumFile(startingAt: start)
+        if let url {
+            fwaSelection = .custom
+            fwaCustomPath = url.path
+        }
+    }
+
+    func browseForCalibrationFile() {
+        let start = wizard.effectiveWorkingDirectory
+        let url = fileDialogs.selectCalFile(startingAt: start)
+        if let url {
+            calibrationFile = url.path
+            applyCalibration = true
+        }
+    }
+}

Sources/ICCery/RootView.swift

@@ -1,16 +1,20 @@
+import AppKit
 import SwiftUI
+import ICCeryCore
 
 /// Root layout: 270 pt sidebar + main stage area with the notification
 /// banner pinned to the top (docs/21 §Shell).
 struct RootView: View {
-    @Bindable var model: WizardViewModel
+    @Bindable var workflow: TargetWorkflowViewModel
     @State private var showingSettings = false
     @State private var showingAbout = false
 
+    private var model: WizardViewModel { workflow.wizard }
+
     var body: some View {
         HStack(spacing: 0) {
             SidebarView(
-                model: model,
+                workflow: workflow,
                 onOpenSettings: { showingSettings = true },
                 onOpenAbout: { showingAbout = true }
             )
@@ -23,21 +27,26 @@ struct RootView: View {
                 if let notice = model.notice {
                     NoticeBanner(notice: notice, onClose: model.dismissNotice)
                 }
-                StagePlaceholderView(stage: model.stage)
+                stageContent
             }
         }
         .frame(minWidth: 1100, minHeight: 700)
         .background(Theme.background)
+        // #151: re-probe artefacts when the window regains focus —
+        // files deleted in Finder must re-lock stages.
+        .onReceive(
+            NotificationCenter.default.publisher(
+                for: NSWindow.didBecomeKeyNotification
+            )
+        ) { _ in model.windowDidBecomeKey() }
         .sheet(isPresented: $showingSettings) {
-            // Full settings dialog lands in issue #5.
-            VStack(spacing: 12) {
-                Text("Settings").font(.headline)
-                Text("Implemented in issue #5.")
-                    .foregroundStyle(.secondary)
-                Button("Close") { showingSettings = false }
-            }
-            .padding(24)
-            .frame(width: 420)
+            SettingsView()
+        }
+        .sheet(isPresented: $workflow.showingSavePreset) {
+            SavePresetDialog(workflow: workflow)
+        }
+        .sheet(isPresented: $workflow.showingManagePresets) {
+            ManagePresetsDialog(workflow: workflow)
         }
         .alert("ICCery 2.0.0", isPresented: $showingAbout) {
             Button("OK") {}
@@ -45,4 +54,22 @@ struct RootView: View {
             Text("Native macOS printer profiling workstation.\nFull About dialog lands in issue #31.")
         }
     }
+
+    @ViewBuilder
+    private var stageContent: some View {
+        switch model.stage {
+        case .generate:
+            Stage1View(workflow: workflow)
+        case .layOutPrint:
+            Stage2View(workflow: workflow)
+        case .measure:
+            Stage3View(model: workflow.measurement)
+        case .buildProfile:
+            Stage4View(model: workflow.profile)
+        case .verifyInstall:
+            Stage5View(model: workflow.profile)
+        default:
+            StagePlaceholderView(stage: model.stage)
+        }
+    }
 }

Sources/ICCery/SettingsView.swift

@@ -0,0 +1,169 @@
+import SwiftUI
+import ICCeryCore
+
+/// Settings sheet (issue #5, docs/21 §Settings). Dark-theme Form with
+/// the full v1 field set; ΔE validation shows inline under the fields.
+struct SettingsView: View {
+    @State var model = SettingsViewModel()
+    @Environment(\.dismiss) private var dismiss
+
+    private static let instruments: [(code: String, label: String)] = [
+        ("i1", "X-Rite i1Pro / i1Pro 2"),
+        ("p3", "X-Rite i1Pro 3 / 3 Plus"),
+        ("CM", "ColorMunki"),
+        ("SS", "Specbos / Spectraval"),
+        ("20", "Gretag i1Display 2"),
+        ("22", "X-Rite i1Display Pro / ColorMunki Display"),
+        ("41", "Datacolor Spyder 4/5"),
+        ("51", "Spyder X"),
+    ]
+
+    var body: some View {
+        VStack(spacing: 0) {
+            Form {
+                Section("Argyll") {
+                    HStack {
+                        TextField(
+                            "Bundled sidecars",
+                            text: Binding(
+                                get: { model.settings.argyllBinaryDir ?? "" },
+                                set: {
+                                    model.settings.argyllBinaryDir =
+                                        $0.isEmpty ? nil : $0
+                                }
+                            )
+                        )
+                        Button("Browse…") {
+                            if let dir = FileDialogService.shared.selectDirectory() {
+                                model.settings.argyllBinaryDir = dir.path
+                            }
+                        }
+                    }
+                    Text("Leave empty to use the bundled Argyll tools.")
+                        .font(.caption)
+                        .foregroundStyle(.secondary)
+
+                    Picker(
+                        "Default instrument",
+                        selection: Binding(
+                            get: { model.settings.defaultInstrument ?? "" },
+                            set: {
+                                model.settings.defaultInstrument =
+                                    $0.isEmpty ? nil : $0
+                            }
+                        )
+                    ) {
+                        Text("None").tag("")
+                        ForEach(Self.instruments, id: \.code) {
+                            Text($0.label).tag($0.code)
+                        }
+                    }
+                    Text("Display-only — Stage 2's instrument select is used for actual runs.")
+                        .font(.caption)
+                        .foregroundStyle(.secondary)
+
+                    Toggle(
+                        "Enable i1Pro 2 LEDs",
+                        isOn: $model.settings.enableI1Pro2Leds
+                    )
+                }
+
+                Section("Verification") {
+                    HStack {
+                        Text("Good ΔE ≤")
+                        TextField(
+                            "2.0",
+                            value: $model.settings.deltaEGoodMax,
+                            format: .number
+                        )
+                        .frame(width: 60)
+                        Text("Warning ΔE ≤")
+                        TextField(
+                            "5.0",
+                            value: $model.settings.deltaEWarningMax,
+                            format: .number
+                        )
+                        .frame(width: 60)
+                    }
+                    ForEach(model.validationErrors, id: \.self) { error in
+                        Text(error)
+                            .font(.caption)
+                            .foregroundStyle(.red)
+                    }
+                }
+
+                Section("Calibration") {
+                    HStack {
+                        Text("Stale after")
+                        TextField(
+                            "30",
+                            value: $model.settings.calibrationStaleDays,
+                            format: .number
+                        )
+                        .frame(width: 60)
+                        Text("days")
+                    }
+                }
+
+                Section("Profile install") {
+                    Picker(
+                        "Install location",
+                        selection: $model.settings.defaultInstallLocation
+                    ) {
+                        Text("User library").tag(InstallLocation.user)
+                        Text("System library").tag(InstallLocation.system)
+                    }
+                    Toggle(
+                        "Ask before overwriting a profile",
+                        isOn: $model.settings.askBeforeOverwriteProfile
+                    )
+                    Toggle(
+                        "Open ColorSync after install",
+                        isOn: $model.settings.openColorPanelAfterInstall
+                    )
+                }
+
+                Section("Logging") {
+                    Picker(
+                        "Log level",
+                        selection: Binding(
+                            get: { model.settings.logLevel },
+                            set: { model.settings.logLevel = $0 }
+                        )
+                    ) {
+                        Text("Default").tag(LogLevel?.none)
+                        ForEach(LogLevel.allCases, id: \.self) {
+                            Text($0.rawValue.capitalized).tag(LogLevel?.some($0))
+                        }
+                    }
+                    HStack {
+                        Button("Open log folder") { model.openLogFolder() }
+                        Button("Copy path") { model.copyLogPath() }
+                        Button("Copy excerpt") { model.copyLogExcerpt() }
+                    }
+                }
+            }
+            .formStyle(.grouped)
+
+            Divider()
+
+            HStack {
+                if model.savedFlash {
+                    Text("Saved")
+                        .foregroundStyle(.green)
+                        .font(.callout)
+                }
+                Spacer()
+                Button("Cancel") { dismiss() }
+                    .keyboardShortcut(.cancelAction)
+                Button("Save") {
+                    if model.save() { dismiss() }
+                }
+                .keyboardShortcut(.defaultAction)
+            }
+            .padding(12)
+        }
+        .frame(width: 560, height: 620)
+        .background(Theme.background)
+    }
+}

Sources/ICCery/SettingsViewModel.swift

@@ -0,0 +1,68 @@
+import AppKit
+import Foundation
+import ICCeryCore
+
+/// Backs the Settings sheet (issue #5). Load → edit → save with
+/// validation; the log level is applied live via `LogSink` (#158) and a
+/// `settingsDidChange` notification fans out to #20.
+@MainActor
+@Observable
+final class SettingsViewModel {
+
+    var settings: AppSettings
+    var validationErrors: [String] = []
+    var savedFlash = false
+
+    private let store: SettingsStore
+    private let sink: LogSink
+
+    init(store: SettingsStore = SettingsStore(), sink: LogSink = .shared) {
+        self.store = store
+        self.sink = sink
+        self.settings = store.load()
+    }
+
+    /// Persists after validation. Returns false (and shows inline
+    /// errors) when the form is invalid.
+    @discardableResult
+    func save() -> Bool {
+        validationErrors = settings.validate()
+        guard validationErrors.isEmpty else { return false }
+        do {
+            try store.save(settings)
+            sink.applySettings(settings)
+            savedFlash = true
+            Task {
+                try? await Task.sleep(for: .seconds(1.5))
+                savedFlash = false
+            }
+            return true
+        } catch {
+            validationErrors = ["Could not save settings: \(error.localizedDescription)"]
+            return false
+        }
+    }
+
+    // MARK: - Log helpers
+
+    var logFileURL: URL { AppPaths.logFile }
+
+    func openLogFolder() {
+        try? FileManager.default.createDirectory(
+            at: AppPaths.logDir, withIntermediateDirectories: true
+        )
+        NSWorkspace.shared.selectFile(
+            AppPaths.logFile.path, inFileViewerRootedAtPath: AppPaths.logDir.path
+        )
+    }
+
+    func copyLogPath() {
+        NSPasteboard.general.clearContents()
+        NSPasteboard.general.setString(AppPaths.logFile.path, forType: .string)
+    }
+
+    func copyLogExcerpt() {
+        NSPasteboard.general.clearContents()
+        NSPasteboard.general.setString(sink.tailExcerpt(), forType: .string)
+    }
+}

Sources/ICCery/SidebarView.swift

@@ -4,10 +4,12 @@ import ICCeryCore
 /// 270 pt sidebar (docs/21 §Shell): logo, settings/about buttons, preset
 /// select, Calibrate Printer + status chip, and the 1–5 stepper.
 struct SidebarView: View {
-    @Bindable var model: WizardViewModel
+    @Bindable var workflow: TargetWorkflowViewModel
     var onOpenSettings: () -> Void
     var onOpenAbout: () -> Void
 
+    private var model: WizardViewModel { workflow.wizard }
+
     var body: some View {
         VStack(alignment: .leading, spacing: 0) {
             HStack {
@@ -31,21 +33,46 @@ struct SidebarView: View {
 
             Divider().overlay(Theme.border)
 
-            // Preset select (`#presetSelect`). Preset engine lands in #11.
-            Picker("Preset", selection: .constant("none")) {
+            // Preset select (`#presetSelect`) — issue #11. Selection
+            // applies the preset immediately; names render via Text only.
+            Picker("Preset", selection: Binding(
+                get: { workflow.selectedPresetID },
+                set: { id in
+                    if id == "none" {
+                        workflow.selectedPresetID = "none"
+                    } else if let preset = workflow.presets.first(where: { $0.id == id }) {
+                        workflow.applyPreset(preset)
+                    }
+                }
+            )) {
                 Text("No preset").tag("none")
+                ForEach(workflow.presets) { preset in
+                    Text(preset.name).tag(preset.id)
+                }
             }
             .pickerStyle(.menu)
+            .accessibilityIdentifier("presetSelect")
             .padding(.horizontal, 12)
             .padding(.vertical, 8)
 
-            // Calibrate Printer (`#btnCalibratePrinter`); `#calStatusChip`
-            // is hidden until the calibration library lands in #29.
+            HStack(spacing: 8) {
+                Button("Save") { workflow.showingSavePreset = true }
+                    .accessibilityIdentifier("btnSavePresetModal")
+                Button("Manage") { workflow.showingManagePresets = true }
+                    .accessibilityIdentifier("btnOpenPresetsDialog")
+                Spacer()
+            }
+            .padding(.horizontal, 12)
+            .padding(.bottom, 8)
+
+            // Calibrate Printer (`#btnCalibratePrinter`). Disabled until
+            // Stage 0 lands in issue #29; `#calStatusChip` likewise.
             Button(action: { model.enterCalibration() }) {
                 Label("Calibrate Printer", systemImage: "slider.horizontal.3")
                     .frame(maxWidth: .infinity)
             }
             .controlSize(.large)
+            .disabled(true)
             .padding(.horizontal, 12)
 
             Divider().overlay(Theme.border)
@@ -56,7 +83,9 @@ struct SidebarView: View {
                 ForEach(WizardStage.stepperStages, id: \.self) { stage in
                     StepperRow(
                         stage: stage,
-                        isActive: model.stage == stage
+                        isActive: model.stage == stage,
+                        // Artefact gating (issue #4) — disk is truth.
+                        isEnabled: model.isUnlocked(stage)
                     ) {
                         model.go(to: stage)
                     }
@@ -74,6 +103,7 @@ struct SidebarView: View {
 private struct StepperRow: View {
     let stage: WizardStage
     let isActive: Bool
+    let isEnabled: Bool
     let action: () -> Void
 
     var body: some View {
@@ -97,6 +127,8 @@ private struct StepperRow: View {
             .contentShape(Rectangle())
         }
         .buttonStyle(.plain)
+        .disabled(!isEnabled)
+        .opacity(isEnabled ? 1 : 0.45)
         .background(
             RoundedRectangle(cornerRadius: Theme.Metrics.cornerMedium)
                 .fill(isActive ? Theme.accent.opacity(0.15) : .clear)

Sources/ICCery/Stage1View.swift

@@ -0,0 +1,255 @@
+import SwiftUI
+import ICCeryCore
+
+/// Stage 1 — `#stage-1` Generate Target (`targen` → `.ti1`, issue #7,
+/// docs/08). All documented element ids are wired as accessibility
+/// identifiers so the UI-test contract stays stable.
+struct Stage1View: View {
+    @Bindable var workflow: TargetWorkflowViewModel
+
+    var body: some View {
+        ScrollView {
+            VStack(alignment: .leading, spacing: 16) {
+                colourSpaceSection
+                patchSection
+                targetSection
+                advancedSection
+                actionRow
+                logSection
+            }
+            .padding(20)
+            .frame(maxWidth: .infinity, alignment: .leading)
+        }
+        .background(Theme.background)
+        .accessibilityIdentifier("stage-1")
+    }
+
+    // MARK: - Colour space (name="colourSpace")
+
+    private var colourSpaceSection: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            Text("Colour space").font(.headline).foregroundStyle(Theme.text)
+            Picker("Colour space", selection: $workflow.colourSpace) {
+                Text("RGB (print drivers)").tag(ColourSpace.rgb)
+                Text("CMYK (RIP output)").tag(ColourSpace.cmyk)
+            }
+            .pickerStyle(.segmented)
+            .accessibilityIdentifier("colourSpace")
+        }
+    }
+
+    // MARK: - Patch count + white/black
+
+    private var patchSection: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            Text("Patches").font(.headline).foregroundStyle(Theme.text)
+            HStack(spacing: 16) {
+                Picker("Patch count", selection: $workflow.patchPreset) {
+                    ForEach(PatchCountPreset.allCases, id: \.self) {
+                        Text($0.title).tag($0)
+                    }
+                }
+                .accessibilityIdentifier("patchCountPreset")
+                .frame(maxWidth: 220)
+
+                if workflow.patchPreset == .custom {
+                    TextField("Patches", value: $workflow.customPatchCount, format: .number)
+                        .textFieldStyle(.roundedBorder)
+                        .frame(width: 90)
+                        .accessibilityIdentifier("patchCountCustom")
+                }
+            }
+            HStack(spacing: 16) {
+                Stepper(value: $workflow.whitePatches, in: 0...50) {
+                    Text("White patches: \(workflow.whitePatches)")
+                }
+                .accessibilityIdentifier("whitePatches")
+                Stepper(value: $workflow.blackPatches, in: 0...50) {
+                    Text("Black patches: \(workflow.blackPatches)")
+                }
+                .accessibilityIdentifier("blackPatches")
+            }
+            .foregroundStyle(Theme.text)
+        }
+    }
+
+    // MARK: - Target file / working directory
+
+    private var targetSection: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            Text("Target file").font(.headline).foregroundStyle(Theme.text)
+            HStack(spacing: 8) {
+                TextField("Basename (no extension)", text: $workflow.targetBasename)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("targetBasename")
+                Button("Browse…") { workflow.browseForTargetFile() }
+                    .accessibilityIdentifier("btnBrowse")
+                Button("Working Dir…") { workflow.browseForWorkingDirectory() }
+                Button("Open Existing…") { workflow.openExistingTarget() }
+                    .accessibilityIdentifier("btnOpenExisting")
+                Button("Import Dataset…") { workflow.importMeasurementDataset() }
+                    .accessibilityIdentifier("btn-import-dataset")
+            }
+            Text(workflow.targetDirectory?.path ?? "No working directory selected")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+                .textSelection(.enabled)
+                .accessibilityIdentifier("selectedPathDisplay")
+        }
+    }
+
+    // MARK: - Advanced (#targenAdvancedDetails)
+
+    /// UI tests pre-expand the group — XCUI cannot reliably toggle a
+    /// macOS `DisclosureTriangle` (its click lands on the label).
+    @State private var advancedExpanded = UITestHooks.isEnabled
+
+    private var advancedSection: some View {
+        DisclosureGroup("Advanced", isExpanded: $advancedExpanded) {
+            VStack(alignment: .leading, spacing: 12) {
+                HStack(alignment: .top, spacing: 24) {
+                    VStack(alignment: .leading, spacing: 10) {
+                        optionalInt("Grey steps (-g)",
+                                    enabled: $workflow.greyStepsEnabled,
+                                    value: $workflow.greySteps)
+                        .accessibilityIdentifier("targenGreySteps")
+                        optionalInt("Single-channel steps (-s)",
+                                    enabled: $workflow.singleChannelEnabled,
+                                    value: $workflow.singleChannelSteps)
+                        .accessibilityIdentifier("targenSingleChannelSteps")
+                        optionalInt("Neutral steps (-n)",
+                                    enabled: $workflow.neutralStepsEnabled,
+                                    value: $workflow.neutralSteps)
+                        .accessibilityIdentifier("targenNeutralSteps")
+                        optionalDouble("Neutral concentration (-N)",
+                                       enabled: $workflow.neutralConcEnabled,
+                                       value: $workflow.neutralConcentration,
+                                       range: 0.0...1.0)
+                        .accessibilityIdentifier("targenNeutralConcentration")
+                        optionalDouble("OFPS adaptation (-A)",
+                                       enabled: $workflow.adaptationEnabled,
+                                       value: $workflow.adaptation,
+                                       range: 0.0...1.0)
+                        .accessibilityIdentifier("targenAdaptation")
+                    }
+                    VStack(alignment: .leading, spacing: 10) {
+                        HStack {
+                            TextField("Preconditioning profile",
+                                      text: Binding(
+                                        get: { workflow.preconditioningProfile ?? "" },
+                                        set: {
+                                            workflow.preconditioningProfile =
+                                                $0.isEmpty ? nil : $0
+                                        }))
+                                .textFieldStyle(.roundedBorder)
+                                .accessibilityIdentifier("targenPrecondProfile")
+                            Button("…") { workflow.browseForPreconditioningProfile() }
+                                .accessibilityIdentifier("btnBrowsePrecondProfile")
+                        }
+                        Toggle("OFPS high quality (-G)", isOn: $workflow.highQuality)
+                            .accessibilityIdentifier("targenHighQuality")
+                        Picker("Full-spread algorithm", selection: $workflow.algorithm) {
+                            ForEach(FullSpreadAlgorithm.allCases, id: \.self) {
+                                Text($0.displayName).tag($0)
+                            }
+                        }
+                        .accessibilityIdentifier("targenAlgorithm")
+                        if workflow.colourSpace == .cmyk {
+                            optionalInt("Total ink limit (-l)",
+                                        enabled: $workflow.inkLimitEnabled,
+                                        value: $workflow.totalInkLimit)
+                            .accessibilityElement(children: .contain)
+                            .accessibilityIdentifier("targenInkLimitGroup")
+                        }
+                        optionalDouble("Dark emphasis (-V)",
+                                       enabled: $workflow.darkEmphasisEnabled,
+                                       value: $workflow.darkEmphasis,
+                                       range: 0.0...3.0)
+                        .accessibilityIdentifier("targenDarkEmphasis")
+                        optionalDouble("Device power (-p)",
+                                       enabled: $workflow.devicePowerEnabled,
+                                       value: $workflow.devicePower,
+                                       range: 0.0...3.0)
+                        .accessibilityIdentifier("targenDevicePower")
+                    }
+                }
+            }
+            .foregroundStyle(Theme.text)
+            .padding(.top, 8)
+        }
+        .foregroundStyle(Theme.text)
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("targenAdvancedDetails")
+    }
+
+    private func optionalInt(
+        _ title: String,
+        enabled: Binding<Bool>,
+        value: Binding<Int>
+    ) -> some View {
+        HStack {
+            Toggle(title, isOn: enabled)
+                .toggleStyle(.checkbox)
+            if enabled.wrappedValue {
+                TextField("", value: value, format: .number)
+                    .textFieldStyle(.roundedBorder)
+                    .frame(width: 70)
+            }
+        }
+    }
+
+    private func optionalDouble(
+        _ title: String,
+        enabled: Binding<Bool>,
+        value: Binding<Double>,
+        range: ClosedRange<Double>
+    ) -> some View {
+        VStack(alignment: .leading) {
+            Toggle(title, isOn: enabled)
+                .toggleStyle(.checkbox)
+            if enabled.wrappedValue {
+                HStack {
+                    Slider(value: value, in: range)
+                    Text(value.wrappedValue, format: .number.precision(.fractionLength(2)))
+                        .frame(width: 44)
+                        .monospacedDigit()
+                }
+            }
+        }
+    }
+
+    // MARK: - Actions + log
+
+    private var actionRow: some View {
+        HStack {
+            Button(action: workflow.generateTarget) {
+                Label(workflow.targenRunning ? "Generating…" : "Generate Target",
+                      systemImage: "square.grid.3x3")
+            }
+            .controlSize(.large)
+            .disabled(!workflow.canGenerate || workflow.targenRunning)
+            .accessibilityIdentifier("btnGenerate")
+            if workflow.targenRunning {
+                ProgressView().controlSize(.small)
+            }
+            Spacer()
+        }
+    }
+
+    private var logSection: some View {
+        DisclosureGroup("Process log") {
+            ScrollView {
+                Text(workflow.targenLog.joined(separator: "\n"))
+                    .font(.system(.caption, design: .monospaced))
+                    .foregroundStyle(Theme.text)
+                    .frame(maxWidth: .infinity, alignment: .leading)
+                    .textSelection(.enabled)
+            }
+            .frame(minHeight: 120, maxHeight: 200)
+            .accessibilityIdentifier("targenLog")
+        }
+        .foregroundStyle(Theme.text)
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("targenLogContainer")
+    }
+}

Sources/ICCery/Stage2View.swift

@@ -0,0 +1,377 @@
+import SwiftUI
+import ICCeryCore
+
+/// Stage 2 — `#stage-2` Lay Out & Print (`printtarg` → `.ti2` + TIFFs,
+/// issues #9/#10, docs/09). Print controls are visible but inert —
+/// real spooling lands in M3.
+struct Stage2View: View {
+    @Bindable var workflow: TargetWorkflowViewModel
+
+    var body: some View {
+        ScrollView {
+            VStack(alignment: .leading, spacing: 16) {
+                cmWarning
+                formSection
+                labelSection
+                actionRow
+                logSection
+                gallerySection
+                printPanel
+            }
+            .padding(20)
+            .frame(maxWidth: .infinity, alignment: .leading)
+        }
+        .background(Theme.background)
+        .accessibilityIdentifier("stage-2")
+    }
+
+    // MARK: - Colour-management warning (#cmWarningBanner)
+
+    private var cmWarning: some View {
+        HStack(spacing: 10) {
+            Image(systemName: "exclamationmark.triangle.fill")
+                .foregroundStyle(.orange)
+            Text("Set your printer driver to “No Colour Adjustment” " +
+                 "(Epson) / “Off (No Colour Adjustment)” (Canon) before printing. " +
+                 "Any driver colour management corrupts the target.")
+                .font(.callout)
+                .foregroundStyle(Theme.text)
+            Spacer()
+        }
+        .padding(10)
+        .background(Color.orange.opacity(0.12))
+        .clipShape(RoundedRectangle(cornerRadius: Theme.Metrics.cornerMedium))
+        .overlay(
+            RoundedRectangle(cornerRadius: Theme.Metrics.cornerMedium)
+                .stroke(Color.orange.opacity(0.4))
+        )
+        .accessibilityIdentifier("cmWarningBanner")
+    }
+
+    // MARK: - Layout form
+
+    private var formSection: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            HStack(spacing: 16) {
+                Picker("Instrument", selection: $workflow.instrument) {
+                    ForEach(PrintInstrument.allCases, id: \.self) {
+                        Text($0.displayName).tag($0)
+                    }
+                }
+                .accessibilityIdentifier("instrumentSelect")
+                Picker("Page size", selection: $workflow.pageSize) {
+                    ForEach(PageSize.allCases, id: \.self) {
+                        Text($0.rawValue).tag($0)
+                    }
+                }
+                .accessibilityIdentifier("pageSizeSelect")
+            }
+            if workflow.pageSize == .custom {
+                HStack(spacing: 8) {
+                    Text("Custom size (mm):")
+                    TextField("W", value: $workflow.customPageW, format: .number)
+                        .textFieldStyle(.roundedBorder).frame(width: 70)
+                        .accessibilityIdentifier("customPageW")
+                    Text("×")
+                    TextField("H", value: $workflow.customPageH, format: .number)
+                        .textFieldStyle(.roundedBorder).frame(width: 70)
+                        .accessibilityIdentifier("customPageH")
+                }
+                .accessibilityElement(children: .contain)
+                .accessibilityIdentifier("customPageSizeRow")
+            }
+            HStack(spacing: 16) {
+                Picker("Bit depth", selection: $workflow.bitDepth) {
+                    Text("8-bit TIFF").tag(TiffBitDepth.eight)
+                    Text("16-bit TIFF").tag(TiffBitDepth.sixteen)
+                }
+                Stepper("DPI: \(workflow.tiffDpi)",
+                        value: $workflow.tiffDpi, in: 72...600, step: 1)
+                    .accessibilityIdentifier("tiffDpi")
+            }
+            HStack(spacing: 16) {
+                Picker("Layout order", selection: $workflow.layoutOrder) {
+                    ForEach(LayoutOrder.allCases, id: \.self) {
+                        Text($0.displayName).tag($0)
+                    }
+                }
+                .accessibilityIdentifier("printtargLayoutOrder")
+                if workflow.layoutOrder == .customSeed {
+                    HStack {
+                        Text("Seed:")
+                        TextField("", value: $workflow.customSeed, format: .number)
+                            .textFieldStyle(.roundedBorder).frame(width: 80)
+                            .accessibilityIdentifier("printtargCustomSeed")
+                    }
+                    .accessibilityElement(children: .contain)
+                    .accessibilityIdentifier("printtargCustomSeedGroup")
+                }
+            }
+        }
+        .foregroundStyle(Theme.text)
+    }
+
+    // MARK: - Label (#btnToggleLabelEdit / #targetLabelPreview)
+
+    private var labelSection: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            HStack {
+                Text("Chart label").font(.headline).foregroundStyle(Theme.text)
+                Spacer()
+                Button(workflow.labelIsCustom ? "Use automatic label" : "Edit label…") {
+                    workflow.labelIsCustom.toggle()
+                }
+                .accessibilityIdentifier("btnToggleLabelEdit")
+            }
+            HStack(spacing: 12) {
+                TextField("Printer", text: $workflow.metaPrinter)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("targetMetadataPrinter")
+                TextField("Ink set", text: $workflow.metaInkSet)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("targetMetadataInkSet")
+            }
+            HStack(spacing: 12) {
+                TextField("Driver paper", text: $workflow.metaDriverPaper)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("targetMetadataDriverPaper")
+                TextField("Actual paper", text: $workflow.metaActualPaper)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("targetMetadataActualPaper")
+            }
+            if workflow.labelIsCustom {
+                TextField("Custom label", text: $workflow.customLabel)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("targetLabelPreview")
+            } else {
+                Text(workflow.automaticLabel)
+                    .font(.caption)
+                    .foregroundStyle(.secondary)
+                    .accessibilityIdentifier("targetLabelPreview")
+            }
+        }
+    }
+
+    // MARK: - Actions + log
+
+    private var actionRow: some View {
+        HStack {
+            Button(action: workflow.createLayout) {
+                Label(workflow.printtargRunning ? "Creating layout…" : "Create Layout",
+                      systemImage: "rectangle.grid.2x2")
+            }
+            .controlSize(.large)
+            .disabled(workflow.printtargRunning || workflow.wizard.basename.isEmpty)
+            .accessibilityIdentifier("btnCreateLayout")
+            if workflow.printtargRunning {
+                ProgressView().controlSize(.small)
+            }
+            Spacer()
+        }
+    }
+
+    private var logSection: some View {
+        DisclosureGroup("Process log") {
+            ScrollView {
+                Text(workflow.printtargLog.joined(separator: "\n"))
+                    .font(.system(.caption, design: .monospaced))
+                    .foregroundStyle(Theme.text)
+                    .frame(maxWidth: .infinity, alignment: .leading)
+                    .textSelection(.enabled)
+            }
+            .frame(minHeight: 100, maxHeight: 180)
+            .accessibilityIdentifier("printtargLog")
+        }
+        .foregroundStyle(Theme.text)
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("printtargLogContainer")
+    }
+
+    // MARK: - TIFF gallery (#tiffGallery) — host-side PNG only (#58)
+
+    @ViewBuilder
+    private var gallerySection: some View {
+        if let result = workflow.printtargResult {
+            VStack(alignment: .leading, spacing: 8) {
+                Text("Target pages — \(result.manifest.pages.count) page(s), " +
+                     "\(result.manifest.pages.reduce(0) { $0 + $1.patches }) patches")
+                    .font(.headline).foregroundStyle(Theme.text)
+                    .accessibilityIdentifier("galleryInfo")
+                LazyVGrid(
+                    columns: [GridItem(.adaptive(minimum: 220))],
+                    spacing: 12
+                ) {
+                    ForEach(result.pages) { page in
+                        GalleryPageView(page: page, workflow: workflow)
+                    }
+                }
+                .accessibilityElement(children: .contain)
+                .accessibilityIdentifier("galleryGrid")
+            }
+            .accessibilityElement(children: .contain)
+            .accessibilityIdentifier("tiffGallery")
+        }
+    }
+
+    // MARK: - Raw print panel (#rawPrintPanel) — unmanaged lp path
+
+    private var printPanel: some View {
+        VStack(alignment: .leading, spacing: 10) {
+            HStack(spacing: 12) {
+                Text("Print").font(.headline).foregroundStyle(Theme.text)
+                if let notice = workflow.printNotice {
+                    Image(systemName: workflow.printNoticeIsError
+                          ? "xmark.circle.fill" : "info.circle.fill")
+                        .foregroundStyle(workflow.printNoticeIsError
+                                         ? .red : .blue)
+                        .accessibilityIdentifier("printNotificationIcon")
+                    Text(notice)
+                        .font(.caption)
+                        .foregroundStyle(workflow.printNoticeIsError
+                                         ? .red : .secondary)
+                        .accessibilityIdentifier("printNotificationText")
+                        .accessibilityValue(notice)
+                }
+                Spacer()
+            }
+
+            // Printer row: select + status + refresh + Preferences.
+            HStack(spacing: 10) {
+                Picker("Printer", selection: $workflow.selectedPrinter) {
+                    ForEach(workflow.printers, id: \.name) { printer in
+                        Text(printer.displayName ?? printer.name)
+                            .tag(printer.name)
+                    }
+                }
+                .frame(maxWidth: 320)
+                .accessibilityIdentifier("printerSelect")
+                .onChange(of: workflow.selectedPrinter) { _, _ in
+                    workflow.selectedTray = nil
+                    workflow.selectedMediaType = nil
+                    Task { @MainActor in await workflow.reloadSelectedCapabilities() }
+                }
+                if let selected = workflow.printers
+                    .first(where: { $0.name == workflow.selectedPrinter }) {
+                    Text(selected.status.rawValue)
+                        .font(.caption).foregroundStyle(.secondary)
+                        .padding(.horizontal, 8).padding(.vertical, 3)
+                        .background(Theme.background)
+                        .clipShape(Capsule())
+                        .accessibilityIdentifier("printerStatusBadge")
+                }
+                Button(action: workflow.refreshPrinters) {
+                    Image(systemName: "arrow.clockwise")
+                }
+                .help("Refresh printer list")
+                .accessibilityIdentifier("btnRefreshPrinters")
+                Button(action: workflow.openPrinterPreferences) {
+                    Image(systemName: "gearshape")
+                }
+                .help("Printer properties — bound NSPrintPanel")
+                .disabled(workflow.selectedPrinter.isEmpty)
+                .accessibilityIdentifier("btnPrinterProperties")
+            }
+
+            // Tray / media / orientation — from queue capabilities.
+            HStack(spacing: 14) {
+                if !workflow.printerCaps.trays.isEmpty {
+                    Picker("Tray", selection: $workflow.selectedTray) {
+                        ForEach(workflow.printerCaps.trays, id: \.id) {
+                            Text($0.name).tag(Optional($0.id))
+                        }
+                    }
+                    .frame(maxWidth: 200)
+                    .accessibilityIdentifier("printerTraySelect")
+                }
+                if !workflow.printerCaps.mediaTypes.isEmpty {
+                    Picker("Media", selection: $workflow.selectedMediaType) {
+                        ForEach(workflow.printerCaps.mediaTypes, id: \.id) {
+                            Text($0.name).tag(Optional($0.id))
+                        }
+                    }
+                    .frame(maxWidth: 240)
+                    .accessibilityElement(children: .contain)
+                    .accessibilityIdentifier("mediaTypeGroup")
+                    .accessibilityIdentifier("printerMediaTypeSelect")
+                }
+                HStack(spacing: 0) {
+                    Button("Portrait") { workflow.printOrientation = "portrait" }
+                        .buttonStyle(.bordered)
+                        .tint(workflow.printOrientation == "portrait" ? .accentColor : .gray)
+                        .accessibilityIdentifier("btnOrientPortrait")
+                    Button("Landscape") { workflow.printOrientation = "landscape" }
+                        .buttonStyle(.bordered)
+                        .tint(workflow.printOrientation == "landscape" ? .accentColor : .gray)
+                        .accessibilityIdentifier("btnOrientLandscape")
+                }
+                Spacer()
+            }
+
+            HStack(spacing: 8) {
+                Button(action: workflow.printAllPages) {
+                    Label(workflow.isPrinting ? "Printing…" : "Print All",
+                          systemImage: "printer")
+                }
+                .controlSize(.large)
+                .disabled(workflow.isPrinting
+                          || workflow.printtargResult == nil
+                          || workflow.selectedPrinter.isEmpty)
+                .accessibilityIdentifier("btnPrintAll")
+                Spacer()
+                Button("Advance to Stage 3") { workflow.advanceToStage3() }
+                    .accessibilityIdentifier("btnAdvanceToStage3")
+                    .disabled(workflow.printtargResult == nil
+                              || !workflow.wizard.isUnlocked(.measure))
+            }
+        }
+        .padding(12)
+        .background(Theme.panel)
+        .clipShape(RoundedRectangle(cornerRadius: Theme.Metrics.cornerMedium))
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("rawPrintPanel")
+        .task(id: workflow.printtargResult?.pages.count) {
+            // Auto-enumerate once a manifest exists and whenever it
+            // changes (e.g. resume from .ti2).
+            if workflow.printers.isEmpty, workflow.printtargResult != nil {
+                workflow.refreshPrinters()
+            }
+        }
+    }
+}
+
+/// One gallery cell: PNG preview + per-page Print button.
+private struct GalleryPageView: View {
+    let page: GalleryPage
+    let workflow: TargetWorkflowViewModel
+
+    var body: some View {
+        VStack(spacing: 6) {
+            if let png = page.previewPNG, let image = NSImage(data: png) {
+                Image(nsImage: image)
+                    .resizable()
+                    .scaledToFit()
+                    .frame(maxHeight: 240)
+            } else {
+                ZStack {
+                    Rectangle().fill(Theme.panel).frame(height: 160)
+                    Text(page.previewError ?? "No preview")
+                        .font(.caption).foregroundStyle(.secondary)
+                }
+            }
+            Text(page.page.filename)
+                .font(.caption).foregroundStyle(Theme.text)
+            Text("\(page.page.patches) patches · " +
+                 "\(Int(page.page.widthMm))×\(Int(page.page.heightMm)) mm")
+                .font(.caption2).foregroundStyle(.secondary)
+            Button("Print") { workflow.printPage(page) }
+                .disabled(workflow.isPrinting
+                          || workflow.selectedPrinter.isEmpty)
+                .accessibilityIdentifier("btnPrintPage-\(page.index)")
+        }
+        .padding(8)
+        .background(Theme.panel)
+        .clipShape(RoundedRectangle(cornerRadius: Theme.Metrics.cornerMedium))
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("galleryPage-\(page.index)")
+    }
+}

Sources/ICCery/Stage3View.swift

@@ -0,0 +1,385 @@
+import Combine
+import SwiftUI
+import ICCeryCore
+
+/// Stage 3 — measurement, live swatches, and multi-pass averaging.
+struct Stage3View: View {
+    @Bindable var model: MeasurementWorkflowViewModel
+
+    var body: some View {
+        VStack(spacing: 0) {
+            header
+            ScrollView {
+                VStack(alignment: .leading, spacing: 16) {
+                    instrumentSection
+                    chartreadControlsSection
+                    xyTableSection
+                    swatchGridSection
+                    averagingSection
+                }
+                .padding(20)
+            }
+        }
+        .frame(maxWidth: .infinity, maxHeight: .infinity)
+        .background(Theme.background)
+        .onAppear { model.discoverPassSnapshots() }
+        .onReceive(NotificationCenter.default.publisher(for: SettingsStore.settingsDidChange)) { _ in
+            model.loadSettings()
+            model.recomputeSwatches()
+        }
+    }
+
+    // MARK: - Header
+
+    @ViewBuilder
+    private var header: some View {
+        HStack(alignment: .firstTextBaseline) {
+            VStack(alignment: .leading, spacing: 4) {
+                if model.resumedFromTi2 {
+                    Label("Resumed from .ti2", systemImage: "arrow.uturn.right")
+                        .font(.callout)
+                        .foregroundStyle(Theme.accent)
+                        .accessibilityIdentifier("stage3LoadedTargetBanner")
+                }
+                Text(model.basename)
+                    .font(.title3)
+                    .foregroundStyle(Theme.text)
+                    .accessibilityIdentifier("stage3TargetBasename")
+                Text("Measure the printed chart with a spectrophotometer.")
+                    .font(.callout)
+                    .foregroundStyle(.secondary)
+                    .accessibilityIdentifier("stage3TargetMeta")
+            }
+
+            Spacer()
+
+            if model.isChartreadRunning {
+                ProgressView()
+                    .scaleEffect(0.8)
+                    .accessibilityIdentifier("readProgress")
+            }
+
+            if let badge = targetBadge {
+                Text(badge)
+                    .font(.caption)
+                    .padding(.horizontal, 8)
+                    .padding(.vertical, 4)
+                    .background(Theme.border)
+                    .cornerRadius(4)
+                    .foregroundStyle(Theme.text)
+                    .accessibilityIdentifier("stage3TargetBadge")
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    private var targetBadge: String? {
+        if model.isFinished { return "All strips read" }
+        if model.isChartreadRunning { return "Reading" }
+        if !model.passSnapshots.isEmpty { return "\(model.passSnapshots.count) pass(es)" }
+        return nil
+    }
+
+    // MARK: - Instrument detection
+
+    @ViewBuilder
+    private var instrumentSection: some View {
+        VStack(alignment: .leading, spacing: 10) {
+            HStack {
+                Text("Instrument")
+                    .font(.headline)
+                    .foregroundStyle(Theme.text)
+                Spacer()
+                Button(action: { model.detectInstruments() }) {
+                    Image(systemName: "arrow.clockwise")
+                }
+                .disabled(!model.canDetect)
+                .accessibilityIdentifier("btnDetectInstruments")
+            }
+
+            if model.detectionError != nil {
+                Text(model.detectionError ?? "")
+                    .font(.caption)
+                    .foregroundStyle(.red)
+            }
+
+            Picker("Instrument", selection: Binding(
+                get: { instrumentTag },
+                set: { newTag in
+                    if newTag.isEmpty {
+                        model.selectedInstrument = .auto
+                    } else if let device = model.instruments.first(where: { "\($0.port)" == newTag }) {
+                        model.selectedInstrument = .device(device)
+                    }
+                }
+            )) {
+                Text("Auto (first available port)").tag("")
+                ForEach(model.instruments) { device in
+                    Text(device.displayName).tag("\(device.port)")
+                }
+            }
+            .pickerStyle(.menu)
+            .accessibilityIdentifier("chartreadInstrumentSelect")
+
+            if model.selectedInstrument.isXY {
+                Text("XY table workflow selected.")
+                    .font(.caption)
+                    .foregroundStyle(Theme.accent)
+                    .accessibilityIdentifier("xyTableHint")
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    private var instrumentTag: String {
+        switch model.selectedInstrument {
+        case .auto:
+            return ""
+        case .device(let device):
+            return "\(device.port)"
+        }
+    }
+
+    // MARK: - Chartread controls
+
+    @ViewBuilder
+    private var chartreadControlsSection: some View {
+        VStack(alignment: .leading, spacing: 10) {
+            HStack {
+                Text("Status")
+                    .font(.headline)
+                    .foregroundStyle(Theme.text)
+                Spacer()
+                Text(model.currentPrompt ?? "Press Start to begin reading.")
+                    .font(.callout)
+                    .foregroundStyle(Theme.text)
+                    .accessibilityIdentifier("chartreadPrompt")
+            }
+
+            if model.showRemoveSheetNotice {
+                Text("Please remove last sheet from table.")
+                    .font(.caption)
+                    .foregroundStyle(Theme.accent)
+            }
+
+            if let lastError = model.lastError {
+                Text(lastError)
+                    .font(.caption)
+                    .foregroundStyle(.red)
+                    .accessibilityIdentifier("chartreadLastError")
+                    .accessibilityValue(lastError)
+            }
+
+            controlButtons
+
+            if !model.chartreadLog.isEmpty {
+                DisclosureGroup("Log") {
+                    VStack(alignment: .leading) {
+                        ForEach(model.chartreadLog, id: \.self) { line in
+                            Text(line)
+                                .font(.system(.caption, design: .monospaced))
+                                .foregroundStyle(.secondary)
+                        }
+                    }
+                }
+                .foregroundStyle(Theme.text)
+                .accessibilityIdentifier("chartreadLogContainer")
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    @ViewBuilder
+    private var controlButtons: some View {
+        HStack(spacing: 12) {
+            if !model.isChartreadRunning {
+                Button("Start Read") {
+                    model.startRead()
+                }
+                .disabled(!model.canStartRead)
+                .accessibilityIdentifier("btnStartRead")
+            }
+
+            if model.isChartreadRunning {
+                switch model.chartreadState {
+                case .calibrating:
+                    Button("Calibrate") { model.calibrate() }
+                        .accessibilityIdentifier("btnCalibrate")
+                case .awaitingStrip:
+                    Button("Trigger") { model.calibrate() }
+                        .accessibilityIdentifier("btnTrigger")
+                    Button("Done & Save") { model.doneAndSave() }
+                        .accessibilityIdentifier("btnDoneReadEarly")
+                case .tablePlaceSheet, .tableAlign, .promptContinue, .warning:
+                    Button(continueTitle) { model.accept() }
+                        .accessibilityIdentifier("btnAccept")
+                case .error:
+                    Button("Retry") { model.retry() }
+                        .accessibilityIdentifier("btnRetry")
+                case .allStripsRead:
+                    Button("Done & Save") { model.doneAndSave() }
+                        .accessibilityIdentifier("btnDoneRead")
+                default:
+                    EmptyView()
+                }
+
+                Button("Cancel") { model.cancelRead() }
+                    .accessibilityIdentifier("btnCancel")
+            }
+        }
+    }
+
+    private var continueTitle: String {
+        if let key = model.requestedWarningKey {
+            return "Continue (send '\(key.uppercased())')"
+        }
+        return "Continue"
+    }
+
+    // MARK: - XY table badges
+
+    @ViewBuilder
+    private var xyTableSection: some View {
+        if model.selectedInstrument.isXY {
+            HStack(spacing: 8) {
+                xyStep("Place", active: model.xyStep == .place, id: "xyStepPlace")
+                xyStep("Align", active: model.xyStep == .align, id: "xyStepAlign")
+                xyStep("Scan", active: model.xyStep == .scan, id: "xyStepScan")
+                xyStep("Remove", active: model.xyStep == .remove, id: "xyStepRemove")
+            }
+            .padding(12)
+            .background(Theme.panel)
+            .accessibilityIdentifier("xyTablePanel")
+        }
+    }
+
+    private func xyStep(_ label: String, active: Bool, id: String) -> some View {
+        Text(label)
+            .font(.caption)
+            .fontWeight(active ? .bold : .regular)
+            .padding(.horizontal, 12)
+            .padding(.vertical, 6)
+            .background(active ? Theme.accent : Theme.border)
+            .foregroundStyle(active ? Color.white : Theme.text)
+            .cornerRadius(4)
+            .accessibilityIdentifier(id)
+    }
+
+    // MARK: - Swatch grid
+
+    @ViewBuilder
+    private var swatchGridSection: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            HStack {
+                Text("Swatches")
+                    .font(.headline)
+                    .foregroundStyle(Theme.text)
+                Spacer()
+                statsView
+            }
+
+            ScrollView([.horizontal, .vertical]) {
+                VStack(alignment: .leading, spacing: 2) {
+                    ForEach(model.swatchRows) { row in
+                        HStack(spacing: 2) {
+                            Text(row.rowId)
+                                .font(.caption)
+                                .foregroundStyle(.secondary)
+                                .frame(width: 24)
+                            ForEach(row.patches) { swatch in
+                                SwatchPatchView(swatch: swatch)
+                            }
+                        }
+                    }
+                }
+                .padding(8)
+            }
+            .frame(minHeight: 120, maxHeight: 360)
+            .background(Theme.panel)
+            .accessibilityIdentifier("swatchGrid")
+        }
+        .padding(16)
+        .background(Theme.background)
+    }
+
+    @ViewBuilder
+    private var statsView: some View {
+        let patches = model.swatchRows.flatMap(\.patches)
+        let valid = patches.compactMap(\.deltaE)
+        let avg = valid.isEmpty ? nil : valid.reduce(0, +) / Double(valid.count)
+        let max = valid.max() ?? 0
+
+        HStack(spacing: 12) {
+            if let avg = avg {
+                Text("avg ΔE \(String(format: "%.2f", avg))")
+                    .font(.caption)
+                    .foregroundStyle(.secondary)
+            }
+            Text("max ΔE \(String(format: "%.2f", max))")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+            Text("\(patches.count) patches")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+        }
+        .accessibilityIdentifier("readStats")
+    }
+
+    // MARK: - Averaging
+
+    @ViewBuilder
+    private var averagingSection: some View {
+        if !model.passSnapshots.isEmpty || model.isFinished {
+            VStack(alignment: .leading, spacing: 10) {
+                HStack {
+                    Text("Averaging")
+                        .font(.headline)
+                        .foregroundStyle(Theme.text)
+                    Spacer()
+                    Text("\(model.passSnapshots.count) pass(es)")
+                        .font(.caption)
+                        .foregroundStyle(Theme.text)
+                        .padding(.horizontal, 8)
+                        .padding(.vertical, 4)
+                        .background(Theme.border)
+                        .cornerRadius(4)
+                        .accessibilityIdentifier("passCounterBadge")
+                }
+
+                ForEach(model.passSnapshots, id: \.lastPathComponent) { url in
+                    Text(url.lastPathComponent)
+                        .font(.caption)
+                        .foregroundStyle(.secondary)
+                }
+                .accessibilityIdentifier("passesList")
+
+                HStack(spacing: 12) {
+                    Button("Measure Another Sheet") {
+                        model.measureAnotherSheet()
+                    }
+                    .disabled(!model.isFinished || model.isChartreadRunning)
+                    .accessibilityIdentifier("btnMeasureAnotherSheet")
+
+                    Button("Finish & Average") {
+                        model.finishAndAverage()
+                    }
+                    .disabled(!model.canFinish || model.isFinishing)
+                    .accessibilityIdentifier("btnFinishAndAverage")
+                }
+
+                if let notice = model.finishNotice {
+                    Text(notice)
+                        .font(.caption)
+                        .foregroundStyle(model.finishNoticeIsError ? .red : .green)
+                }
+            }
+            .padding(16)
+            .background(Theme.panel)
+            .accessibilityElement(children: .contain)
+            .accessibilityIdentifier("chartreadAveragingPanel")
+        }
+    }
+}

Sources/ICCery/Stage4View.swift

@@ -0,0 +1,195 @@
+import SwiftUI
+import ICCeryCore
+
+/// Stage 4 — build an ICC/ICM profile from the canonical `.ti3`.
+struct Stage4View: View {
+    @Bindable var model: ProfileWorkflowViewModel
+
+    var body: some View {
+        VStack(spacing: 0) {
+            header
+            ScrollView {
+                VStack(alignment: .leading, spacing: 16) {
+                    formSection
+                    runSection
+                }
+                .padding(20)
+            }
+        }
+        .frame(maxWidth: .infinity, maxHeight: .infinity)
+        .background(Theme.background)
+        .onAppear { model.restoreCreatedProfileURL() }
+    }
+
+    // MARK: - Header
+
+    @ViewBuilder
+    private var header: some View {
+        HStack(alignment: .firstTextBaseline) {
+            VStack(alignment: .leading, spacing: 4) {
+                Text(model.wizard.basename)
+                    .font(.title3)
+                    .foregroundStyle(Theme.text)
+                    .accessibilityIdentifier("stage4TargetBasename")
+                Text("Build the ICC profile from the measured .ti3.")
+                    .font(.callout)
+                    .foregroundStyle(.secondary)
+                    .accessibilityIdentifier("stage4TargetMeta")
+            }
+
+            Spacer()
+
+            if let progress = model.colprofProgress, model.isColprofRunning {
+                Text(progress)
+                    .font(.caption)
+                    .padding(.horizontal, 8)
+                    .padding(.vertical, 4)
+                    .background(Theme.border)
+                    .cornerRadius(4)
+                    .foregroundStyle(Theme.text)
+                    .accessibilityIdentifier("colprofProgress")
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    // MARK: - Form
+
+    @ViewBuilder
+    private var formSection: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            Text("Profile settings")
+                .font(.headline)
+                .foregroundStyle(Theme.text)
+
+            HStack(spacing: 16) {
+                Picker("Algorithm", selection: $model.algorithm) {
+                    Text("Lab cLUT").tag("l")
+                    Text("XYZ cLUT").tag("x")
+                    Text("Display XYZ+matrix").tag("X")
+                    Text("Matrix").tag("m")
+                }
+                .accessibilityIdentifier("colprofAlgorithm")
+
+                Picker("Quality", selection: $model.quality) {
+                    Text("Low").tag("l")
+                    Text("Medium").tag("m")
+                    Text("High").tag("h")
+                    Text("Ultra").tag("u")
+                }
+                .accessibilityIdentifier("colprofQuality")
+            }
+
+            Picker("FWA / OBA compensation", selection: $model.fwaSelection) {
+                ForEach(ColprofFwaSelection.allCases, id: \.self) { selection in
+                    Text(selection.displayName).tag(selection)
+                }
+            }
+            .accessibilityIdentifier("colprofFwa")
+
+            if model.fwaSelection == .custom {
+                HStack {
+                    TextField("Custom .sp spectrum path", text: $model.fwaCustomPath)
+                        .textFieldStyle(.roundedBorder)
+                        .accessibilityIdentifier("colprofFwaCustomPath")
+                    Button("Browse…") { model.browseForSpectrumFile() }
+                        .accessibilityIdentifier("btnBrowseFwaSp")
+                }
+            }
+
+            HStack(spacing: 16) {
+                TextField("Illuminant", text: $model.illuminant)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("colprofIlluminant")
+
+                TextField("Observer", text: $model.observer)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("colprofObserver")
+            }
+
+            HStack(spacing: 16) {
+                TextField("Input viewing condition", text: $model.inputViewingCond)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("colprofInputViewCond")
+
+                TextField("Output viewing condition", text: $model.outputViewingCond)
+                    .textFieldStyle(.roundedBorder)
+                    .accessibilityIdentifier("colprofOutputViewCond")
+            }
+
+            Text("Use 'none' to skip a viewing condition.")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+
+            TextField("Description", text: $model.profileDescription)
+                .textFieldStyle(.roundedBorder)
+                .accessibilityIdentifier("colprofDescription")
+
+            TextField("Copyright", text: $model.copyright)
+                .textFieldStyle(.roundedBorder)
+                .accessibilityIdentifier("colprofCopyright")
+
+            Toggle("Apply calibration curve", isOn: $model.applyCalibration)
+                .accessibilityIdentifier("colprofApplyCalibration")
+
+            if model.applyCalibration {
+                HStack {
+                    TextField("Calibration .cal file", text: $model.calibrationFile)
+                        .textFieldStyle(.roundedBorder)
+                        .accessibilityIdentifier("colprofCalibrationFile")
+                    Button("Browse…") { model.browseForCalibrationFile() }
+                        .accessibilityIdentifier("btnBrowseCalibrationFile")
+                }
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    // MARK: - Run controls
+
+    @ViewBuilder
+    private var runSection: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            HStack(spacing: 12) {
+                Button("Create Profile") {
+                    model.createProfile()
+                }
+                .disabled(!model.canCreateProfile)
+                .accessibilityIdentifier("btnCreateProfile")
+
+                if model.isColprofRunning {
+                    ProgressView()
+                        .scaleEffect(0.8)
+                        .accessibilityIdentifier("colprofProgressIndicator")
+                }
+
+                Spacer()
+
+                if let lastError = model.lastError {
+                    Text(lastError)
+                        .font(.caption)
+                        .foregroundStyle(.red)
+                        .accessibilityIdentifier("colprofLastError")
+                }
+            }
+
+            if !model.colprofLog.isEmpty {
+                DisclosureGroup("Log") {
+                    VStack(alignment: .leading) {
+                        ForEach(model.colprofLog, id: \.self) { line in
+                            Text(line)
+                                .font(.system(.caption, design: .monospaced))
+                                .foregroundStyle(.secondary)
+                        }
+                    }
+                }
+                .foregroundStyle(Theme.text)
+                .accessibilityIdentifier("colprofLogContainer")
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+}

Sources/ICCery/Stage5View.swift

@@ -0,0 +1,275 @@
+import SwiftUI
+import ICCeryCore
+
+/// Stage 5 — verify the generated profile, track drift, and install.
+struct Stage5View: View {
+    @Bindable var model: ProfileWorkflowViewModel
+
+    var body: some View {
+        VStack(spacing: 0) {
+            header
+            ScrollView {
+                VStack(alignment: .leading, spacing: 16) {
+                    verifySection
+                    if let report = model.profcheckReport {
+                        resultSection(report: report)
+                    }
+                    historySection
+                }
+                .padding(20)
+            }
+        }
+        .frame(maxWidth: .infinity, maxHeight: .infinity)
+        .background(Theme.background)
+        .onAppear {
+            model.restoreCreatedProfileURL()
+            model.loadHistory()
+        }
+        .alert("Install profile", isPresented: $model.showingInstallCollision) {
+            Button("Overwrite", role: .destructive) {
+                model.resolveInstallCollision(policy: .overwrite)
+            }
+            .accessibilityIdentifier("profileOverwriteBtn")
+            Button("Rename") {
+                model.resolveInstallCollision(policy: .rename)
+            }
+            .accessibilityIdentifier("profileRenameBtn")
+            Button("Cancel", role: .cancel) {
+                model.resolveInstallCollision(policy: .cancel)
+            }
+            .accessibilityIdentifier("profileCancelCollisionBtn")
+        } message: {
+            Text(model.installCollisionMessage)
+                .accessibilityIdentifier("profileInstallCollisionMessage")
+        }
+    }
+
+    // MARK: - Header
+
+    @ViewBuilder
+    private var header: some View {
+        HStack(alignment: .firstTextBaseline) {
+            VStack(alignment: .leading, spacing: 4) {
+                Text(model.wizard.basename)
+                    .font(.title3)
+                    .foregroundStyle(Theme.text)
+                    .accessibilityIdentifier("stage5TargetBasename")
+                Text("Verify the profile and compare against historical results.")
+                    .font(.callout)
+                    .foregroundStyle(.secondary)
+                    .accessibilityIdentifier("stage5TargetMeta")
+            }
+
+            Spacer()
+
+            if let alert = model.driftAlert {
+                Text(alert)
+                    .font(.caption)
+                    .padding(.horizontal, 8)
+                    .padding(.vertical, 4)
+                    .background(Color.red.opacity(0.2))
+                    .cornerRadius(4)
+                    .foregroundStyle(.red)
+                    .accessibilityIdentifier("driftAlert")
+            }
+
+            if let warning = model.profcheckWarning, !warning.isEmpty {
+                Text("⚠ \(warning)")
+                    .font(.caption)
+                    .padding(.horizontal, 8)
+                    .padding(.vertical, 4)
+                    .background(Color.red.opacity(0.2))
+                    .cornerRadius(4)
+                    .foregroundStyle(.red)
+                    .accessibilityIdentifier("profcheckWarningBanner")
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    // MARK: - Verify
+
+    @ViewBuilder
+    private var verifySection: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            HStack(spacing: 12) {
+                Button("Verify Profile") {
+                    model.verifyProfile()
+                }
+                .disabled(!model.canVerify)
+                .accessibilityIdentifier("btnVerifyProfile")
+
+                if model.isProfcheckRunning {
+                    ProgressView()
+                        .scaleEffect(0.8)
+                        .accessibilityIdentifier("profcheckProgressIndicator")
+                }
+
+                Spacer()
+
+                if let profileURL = model.createdProfileURL {
+                    Text(profileURL.lastPathComponent)
+                        .font(.caption)
+                        .foregroundStyle(.secondary)
+                        .accessibilityIdentifier("stage5ProfilePath")
+                }
+            }
+
+            if !model.colprofLog.isEmpty {
+                DisclosureGroup("Log") {
+                    VStack(alignment: .leading) {
+                        ForEach(model.colprofLog, id: \.self) { line in
+                            Text(line)
+                                .font(.system(.caption, design: .monospaced))
+                                .foregroundStyle(.secondary)
+                        }
+                    }
+                }
+                .foregroundStyle(Theme.text)
+                .accessibilityIdentifier("profcheckLogContainer")
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    // MARK: - Result cards
+
+    @ViewBuilder
+    private func resultSection(report: ProfcheckReport) -> some View {
+        VStack(alignment: .leading, spacing: 12) {
+            HStack {
+                Text("Verification result")
+                    .font(.headline)
+                    .foregroundStyle(Theme.text)
+
+                Spacer()
+
+                Button("Install Profile") { model.beginInstallProfile() }
+                    .disabled(model.createdProfileURL == nil)
+                    .accessibilityIdentifier("btnInstallProfile")
+            }
+
+            HStack(spacing: 16) {
+                metricCard(title: "Avg ΔE", value: report.avgDE)
+                metricCard(title: "Max ΔE", value: report.maxDE)
+                metricCard(title: "RMS", value: report.rmsDE)
+                metricCard(title: "Patches", value: report.patchCount.map(Double.init))
+            }
+
+            if let status = report.status {
+                HStack {
+                    Text("Status")
+                    Spacer()
+                    Text(status.displayName)
+                        .fontWeight(.semibold)
+                        .foregroundStyle(statusColor(status))
+                        .accessibilityIdentifier("profcheckStatus")
+                }
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    @ViewBuilder
+    private func metricCard(title: String, value: Double?) -> some View {
+        VStack(alignment: .leading, spacing: 4) {
+            Text(title)
+                .font(.caption)
+                .foregroundStyle(.secondary)
+            Text(value.map { String(format: "%.2f", $0) } ?? "—")
+                .font(.title3)
+                .foregroundStyle(Theme.text)
+        }
+        .frame(maxWidth: .infinity, alignment: .leading)
+    }
+
+    // MARK: - History
+
+    @ViewBuilder
+    private var historySection: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            Text("History & drift")
+                .font(.headline)
+                .foregroundStyle(Theme.text)
+
+            HStack {
+                Picker("Printer", selection: Binding(
+                    get: { model.driftPrinterFilter ?? "" },
+                    set: { model.driftPrinterFilter = $0.isEmpty ? nil : $0 }
+                )) {
+                    Text("All").tag("")
+                    ForEach(model.knownPrinters, id: \.self) { printer in
+                        Text(printer.isEmpty ? "Unknown" : printer).tag(printer)
+                    }
+                }
+                .accessibilityIdentifier("driftPrinterFilter")
+                .frame(width: 200)
+
+                Spacer()
+
+                Button("Export CSV") { model.exportHistory() }
+                    .accessibilityIdentifier("btnExportHistory")
+
+                Button("Clear") { model.clearHistory() }
+                    .accessibilityIdentifier("btnClearHistory")
+            }
+
+            driftChart
+
+            if !model.filteredHistory.isEmpty {
+                Table(of: VerificationRecord.self) {
+                    TableColumn("Date") { record in
+                        Text(record.timestamp.formatted(date: .numeric, time: .shortened))
+                    }
+                    TableColumn("Profile") { record in
+                        Text(record.profileName)
+                    }
+                    TableColumn("Avg") { record in
+                        Text(String(format: "%.2f", record.avgDE))
+                    }
+                    TableColumn("Max") { record in
+                        Text(String(format: "%.2f", record.maxDE))
+                    }
+                    TableColumn("RMS") { record in
+                        Text(String(format: "%.2f", record.rmsDE))
+                    }
+                    TableColumn("Status") { record in
+                        Text(record.status.displayName)
+                            .foregroundStyle(statusColor(record.status))
+                    }
+                } rows: {
+                    ForEach(model.filteredHistory) { record in
+                        TableRow(record)
+                    }
+                }
+                .frame(minHeight: 120)
+                .accessibilityIdentifier("verificationHistoryTable")
+            } else {
+                Text("No verification records yet.")
+                    .font(.callout)
+                    .foregroundStyle(.secondary)
+            }
+        }
+        .padding(16)
+        .background(Theme.panel)
+    }
+
+    @ViewBuilder
+    private var driftChart: some View {
+        let records = model.filteredHistory.sorted { $0.timestamp < $1.timestamp }
+        DriftChartView(records: records)
+            .frame(height: 160)
+            .accessibilityIdentifier("driftChart")
+    }
+
+    private func statusColor(_ status: VerificationStatus) -> Color {
+        switch status {
+        case .excellent, .good: return .green
+        case .acceptable: return .yellow
+        case .poor: return .red
+        }
+    }
+}

Sources/ICCery/SwatchPatchView.swift

@@ -0,0 +1,75 @@
+import SwiftUI
+import ICCeryCore
+
+private extension DisplayRGB {
+    var color: Color {
+        Color(red: r, green: g, blue: b)
+    }
+}
+
+/// One swatch in the live grid, with a 135° intended/measured diagonal split.
+struct SwatchPatchView: View {
+    let swatch: Swatch
+
+    private var indicatorColor: Color {
+        switch swatch.classification {
+        case .good: return .green
+        case .warning: return .yellow
+        case .bad: return .red
+        }
+    }
+
+    var body: some View {
+        ZStack {
+            // Background: measured
+            swatch.measured.color
+                .clipShape(DiagonalClip(side: .bottomRight))
+
+            // Foreground: intended
+            swatch.intended.color
+                .clipShape(DiagonalClip(side: .topLeft))
+
+            // Classification dot
+            Circle()
+                .fill(indicatorColor)
+                .frame(width: 6, height: 6)
+                .offset(x: 6, y: 6)
+        }
+        .frame(width: 32, height: 32)
+        .overlay(
+            Rectangle()
+                .stroke(Color.primary.opacity(0.2), lineWidth: 0.5)
+        )
+        .accessibilityIdentifier("swatch-\(swatch.rowId)\(swatch.loc)")
+        .accessibilityLabel("\(swatch.loc) intended \(String(format: "%.0f", swatch.intended.r * 255)), measured \(String(format: "%.0f", swatch.measured.r * 255))")
+    }
+}
+
+/// 135° diagonal clipping: top-left or bottom-right triangle.
+///
+/// A 135° line from the top-right corner to the bottom-left corner gives
+/// top-left and bottom-right triangles.
+private enum DiagonalSide {
+    case topLeft
+    case bottomRight
+}
+
+private struct DiagonalClip: Shape {
+    let side: DiagonalSide
+
+    func path(in rect: CGRect) -> Path {
+        var path = Path()
+        switch side {
+        case .topLeft:
+            path.move(to: CGPoint(x: rect.minX, y: rect.minY))
+            path.addLine(to: CGPoint(x: rect.maxX, y: rect.minY))
+            path.addLine(to: CGPoint(x: rect.minX, y: rect.maxY))
+        case .bottomRight:
+            path.move(to: CGPoint(x: rect.maxX, y: rect.minY))
+            path.addLine(to: CGPoint(x: rect.maxX, y: rect.maxY))
+            path.addLine(to: CGPoint(x: rect.minX, y: rect.maxY))
+        }
+        path.closeSubpath()
+        return path
+    }
+}

Sources/ICCery/TargetWorkflowViewModel.swift

@@ -0,0 +1,700 @@
+import Foundation
+import Observation
+import ICCeryCore
+
+/// Stage 1/2 form state, runner orchestration, resume flow, and preset
+/// application (issues #7–#11).
+///
+/// `wizard` stays authoritative for persisted identity + disk gating;
+/// this model owns the editable form, logs, gallery, and preset state.
+/// All process work runs through `ArgyllRunner` off `@MainActor`; only
+/// coalesced log batches and completion hop back.
+@MainActor
+@Observable
+final class TargetWorkflowViewModel {
+
+    let wizard: WizardViewModel
+    let environment: AppEnvironment
+    private let fileDialogs = FileDialogService.shared
+
+    // MARK: - Stage 1 form (targen)
+
+    var colourSpace: ColourSpace = .rgb {
+        didSet {
+            guard colourSpace != oldValue else { return }
+            // CMYK black patches default to 0, RGB to 4 (docs/08).
+            blackPatches = colourSpace == .cmyk ? 0 : 4
+        }
+    }
+    var patchPreset: PatchCountPreset = .standard800
+    /// `#patchCountCustom` — used when `patchPreset == .custom`.
+    var customPatchCount = 2500
+    var whitePatches = 4
+    var blackPatches = 4
+
+    // Advanced — each optional flag is enabled + value, so an untouched
+    // control emits nothing (#advanced fields are opt-in).
+    var greyStepsEnabled = false
+    var greySteps = 5
+    var singleChannelEnabled = false
+    var singleChannelSteps = 5
+    var neutralStepsEnabled = false
+    var neutralSteps = 3
+    var neutralConcEnabled = false
+    var neutralConcentration = 0.50
+    var preconditioningProfile: String?
+    var highQuality = false
+    var adaptationEnabled = false
+    var adaptation = 0.10
+    var algorithm: FullSpreadAlgorithm = .ofps
+    var inkLimitEnabled = false
+    var totalInkLimit = 320
+    var darkEmphasisEnabled = false
+    var darkEmphasis = 1.0
+    var devicePowerEnabled = false
+    var devicePower = 1.0
+
+    /// `#targetBasename` — no placeholder is ever invented (#60).
+    var targetBasename = ""
+    /// `#selectedPathDisplay` / resolved cwd.
+    var targetDirectory: URL?
+
+    // MARK: - Stage 2 form (printtarg)
+
+    var instrument: PrintInstrument = .i1
+    var pageSize: PageSize = .a4
+    var customPageW = 210.0
+    var customPageH = 297.0
+    var bitDepth: TiffBitDepth = .eight
+    /// `#tiffDpi` — two-way bound; presets can change it (150-DPI draft
+    /// regression must be visible here).
+    var tiffDpi = 300
+    var layoutOrder: LayoutOrder = .deterministic
+    var customSeed = 1
+    var labelIsCustom = false
+    var customLabel = ""
+    var metaPrinter = ""
+    var metaInkSet = ""
+    var metaDriverPaper = ""
+    var metaActualPaper = ""
+
+    // MARK: - Run state
+
+    var targenRunning = false
+    var targenLog: [String] = []
+    var printtargRunning = false
+    var printtargLog: [String] = []
+    var printtargResult: PrinttargResult?
+    /// Sticky until the target changes: `.ti2` resume landed us on
+    /// Stage 3 (`#stage3LoadedTargetBanner` data).
+    var resumedFromTi2 = false
+
+    // MARK: - Print panel (issue 17)
+
+    /// CUPS destinations from `lpstat` (#printerSelect).
+    var printers: [Printer] = []
+    /// Selected queue name.
+    var selectedPrinter = ""
+    /// Capabilities of the selected queue (#printerTraySelect /
+    /// #printerMediaTypeSelect / PageSize source).
+    var printerCaps = PrinterCapabilities()
+    var selectedTray: Int?
+    var selectedMediaType: String?
+    /// "portrait" | "landscape" (#btnOrientPortrait/#btnOrientLandscape).
+    var printOrientation = "portrait"
+    /// Per-queue captured `key=value` strings from Preferences — replayed
+    /// on `lp` (session-only, docs/11 §capturedCupsOptions).
+    var capturedCupsOptions: [String: String] = [:]
+    /// In-panel notice (#printNotification) — cancel → info, not error.
+    var printNotice: String?
+    var printNoticeIsError = false
+    var isPrinting = false
+
+    // MARK: - Presets
+
+    var presets: [ProfilingPreset] = []
+    var selectedPresetID = "none"
+    var showingSavePreset = false
+    var showingManagePresets = false
+    var savePresetName = ""
+    var savePresetDesc = ""
+
+    /// Stage 3 measurement workflow, owned at the app level so it persists
+    /// across stage switches and can observe settings changes.
+    var measurement: MeasurementWorkflowViewModel
+    /// Stage 4/5 profile workflow, owned at the app level so it persists
+    /// across stage switches and can apply preset values.
+    var profile: ProfileWorkflowViewModel
+
+    init(environment: AppEnvironment = .live()) {
+        self.environment = environment
+        self.wizard = WizardViewModel(stateStore: environment.stateStore)
+        self.measurement = MeasurementWorkflowViewModel(
+            wizard: wizard,
+            environment: environment
+        )
+        self.profile = ProfileWorkflowViewModel(
+            wizard: wizard,
+            environment: environment
+        )
+        reloadPresets()
+    }
+
+    // MARK: - Derived
+
+    var effectivePatchCount: Int {
+        patchPreset.patchCount ?? customPatchCount
+    }
+
+    var canGenerate: Bool {
+        PathSecurity.isValidBasename(targetBasename) && targetDirectory != nil
+    }
+
+    var labelMetadata: TargetLabelMetadata {
+        TargetLabelMetadata(
+            printer: metaPrinter, inkSet: metaInkSet,
+            driverPaper: metaDriverPaper, actualPaper: metaActualPaper)
+    }
+
+    /// `#targetLabelPreview` — live preview of the automatic label.
+    var automaticLabel: String {
+        PrinttargLabel.automatic(
+            basename: wizard.basename.isEmpty ? "target" : wizard.basename,
+            metadata: labelMetadata)
+    }
+
+    var selectedPreset: ProfilingPreset? {
+        presets.first { $0.id == selectedPresetID }
+    }
+
+    // MARK: - Stage 1: generate
+
+    func buildTargenConfig() -> TargenConfig {
+        TargenConfig(
+            colourSpace: colourSpace,
+            patchCount: effectivePatchCount,
+            whitePatches: whitePatches,
+            blackPatches: blackPatches,
+            greySteps: greyStepsEnabled ? greySteps : nil,
+            singleChannelSteps: singleChannelEnabled ? singleChannelSteps : nil,
+            neutralSteps: neutralStepsEnabled ? neutralSteps : nil,
+            neutralConcentration: neutralConcEnabled ? neutralConcentration : nil,
+            preconditioningProfile: preconditioningProfile,
+            ofpsHighQuality: highQuality ? true : nil,
+            ofpsAdaptation: adaptationEnabled ? adaptation : nil,
+            fullSpreadAlgorithm: algorithm == .ofps ? nil : algorithm,
+            totalInkLimit: inkLimitEnabled ? totalInkLimit : nil,
+            darkEmphasis: darkEmphasisEnabled ? darkEmphasis : nil,
+            devicePower: devicePowerEnabled ? devicePower : nil,
+            basename: targetBasename,
+            workingDirectory: targetDirectory
+        )
+    }
+
+    func browseForTargetFile() {
+        let url = UITestHooks.isEnabled
+            ? UITestHooks.saveTargetURL
+            : fileDialogs.selectTargetFile()
+        guard let url else { return }
+        targetBasename = url.deletingPathExtension().lastPathComponent
+        targetDirectory = url.deletingLastPathComponent()
+    }
+
+    func browseForWorkingDirectory() {
+        let url = UITestHooks.isEnabled
+            ? UITestHooks.workDirURL
+            : fileDialogs.selectDirectory()
+        if let url { targetDirectory = url }
+    }
+
+    func browseForPreconditioningProfile() {
+        if let url = fileDialogs.selectProfileFile() {
+            preconditioningProfile = url.path
+        }
+    }
+
+    func generateTarget() {
+        guard canGenerate, !targenRunning else { return }
+        let config = buildTargenConfig()
+        targenRunning = true
+        targenLog = []
+        resumedFromTi2 = false
+        let runner = environment.runner
+        Task { @MainActor in
+            do {
+                let url = try await runner.runTargen(config: config) { [weak self] batch in
+                    Task { @MainActor [weak self] in
+                        self?.targenLog.append(contentsOf: batch)
+                    }
+                }
+                wizard.setTarget(
+                    basename: config.basename,
+                    workingDirectory: config.workingDirectory)
+                wizard.refreshGating()
+                wizard.showNotice("Target generated: \(url.lastPathComponent)")
+                wizard.go(to: .layOutPrint)
+            } catch {
+                wizard.showNotice(
+                    "targen failed: \(error.localizedDescription)", kind: .error)
+            }
+            targenRunning = false
+        }
+    }
+
+    // MARK: - Issue 8: resume an existing target
+
+    /// `#btn-import-dataset` — open a measured dataset, write a canonical
+    /// `.ti3` to the working directory, and set the target (issue #30).
+    func importMeasurementDataset() {
+        let url = UITestHooks.isEnabled
+            ? UITestHooks.datasetImportURL
+            : fileDialogs.selectDatasetFile()
+        guard let url else { return }
+
+        do {
+            let dataset = try CGATSParser.parse(url: url)
+            guard let directory = targetDirectory ?? wizard.effectiveWorkingDirectory else {
+                wizard.showNotice("Choose a working directory before importing.", kind: .warning)
+                return
+            }
+
+            let stem = url.deletingPathExtension().lastPathComponent
+            let output = directory.appendingPathComponent("\(stem).ti3")
+            try CGATSWriter.write(dataset, to: output)
+
+            wizard.setTarget(basename: stem, workingDirectory: directory)
+            wizard.refreshGating()
+            wizard.showNotice("Imported \(dataset.samples.count) patches from \(url.lastPathComponent)")
+
+            if wizard.isUnlocked(.verifyInstall) {
+                wizard.go(to: .verifyInstall)
+            } else if wizard.isUnlocked(.buildProfile) {
+                wizard.go(to: .buildProfile)
+            } else {
+                wizard.showNotice("Imported dataset is not ready for profiling.", kind: .warning)
+            }
+        } catch let error as CGATSParseError {
+            wizard.showNotice("Import failed: \(error.localizedDescription)", kind: .error)
+        } catch {
+            wizard.showNotice("Import failed: \(error.localizedDescription)", kind: .error)
+        }
+    }
+
+    /// `#btnOpenExisting` — open `.ti1`/`.ti2` (open dialog, #103).
+    /// `.ti1` → Stage 2; `.ti2` → Stage 3 with the resume notice, but
+    /// only when the sibling `.ti1` exists so the artefact gate holds.
+    func openExistingTarget() {
+        let url = UITestHooks.isEnabled
+            ? UITestHooks.existingTargetURL
+            : fileDialogs.selectExistingTarget()
+        guard let url else { return }
+
+        let stem = url.deletingPathExtension().lastPathComponent
+        let dir = url.deletingLastPathComponent()
+        guard PathSecurity.isValidBasename(stem) else {
+            wizard.showNotice("Invalid target name.", kind: .error)
+            return
+        }
+
+        switch url.pathExtension.lowercased() {
+        case "ti1":
+            wizard.setTarget(basename: stem, workingDirectory: dir)
+            wizard.refreshGating()
+            resumedFromTi2 = false
+            measurement.resumedFromTi2 = false
+            wizard.go(to: .layOutPrint)
+        case "ti2":
+            let header = Ti2Header.parse(url)
+            guard header.hasSiblingTi1 else {
+                wizard.showNotice(
+                    "Cannot resume \(stem).ti2 — the sibling \(stem).ti1 is missing.",
+                    kind: .error)
+                return
+            }
+            wizard.setTarget(basename: stem, workingDirectory: dir)
+            wizard.refreshGating()
+            resumedFromTi2 = true
+            measurement.resumedFromTi2 = true
+            wizard.showNotice("Resumed from .ti2", kind: .info, autoHideAfter: nil)
+            wizard.go(to: .measure)
+        default:
+            wizard.showNotice(
+                "Not a target file — choose a .ti1 or .ti2.", kind: .error)
+        }
+    }
+
+    // MARK: - Stage 2: create layout
+
+    func buildPrinttargConfig() -> PrinttargConfig {
+        PrinttargConfig(
+            instrument: instrument,
+            pageSize: pageSize,
+            customPageWidth: customPageW,
+            customPageHeight: customPageH,
+            bitDepth: bitDepth,
+            dpi: tiffDpi,
+            layoutOrder: layoutOrder,
+            customSeed: customSeed,
+            label: PrinttargLabel.resolved(
+                customLabel: labelIsCustom ? customLabel : nil,
+                basename: wizard.basename,
+                metadata: labelMetadata),
+            basename: wizard.basename,
+            workingDirectory: wizard.effectiveWorkingDirectory
+        )
+    }
+
+    func createLayout() {
+        guard wizard.isUnlocked(.layOutPrint), !printtargRunning else { return }
+        let config = buildPrinttargConfig()
+        printtargRunning = true
+        printtargLog = []
+        printtargResult = nil
+        let runner = environment.runner
+        Task { @MainActor in
+            do {
+                let result = try await runner.runPrinttarg(config: config) { [weak self] batch in
+                    Task { @MainActor [weak self] in
+                        self?.printtargLog.append(contentsOf: batch)
+                    }
+                }
+                printtargResult = result
+                wizard.refreshGating()
+                wizard.showNotice(
+                    "Layout created — \(result.manifest.pages.count) page(s) ready.")
+            } catch {
+                // Stay on Stage 2: non-zero exit, malformed manifest, or
+                // missing .ti2 must never advance the wizard (#156).
+                wizard.showNotice(
+                    "printtarg failed: \(error.localizedDescription)", kind: .error)
+            }
+            printtargRunning = false
+        }
+    }
+
+    /// `#btnAdvanceToStage3` — manual advance once `.ti2` exists.
+    func advanceToStage3() {
+        wizard.refreshGating()
+        wizard.go(to: .measure)
+    }
+
+    // MARK: - Print panel actions (issue 17)
+
+    /// `#btnRefreshPrinters` — re-enumerate CUPS destinations and load
+    /// capabilities for the selection. Auto-runs when the panel first
+    /// appears with a manifest.
+    func refreshPrinters() {
+        let cups = environment.cupsService
+        Task { @MainActor in
+            do {
+                let list = try await cups.listPrinters()
+                printers = list
+                if !list.contains(where: { $0.name == selectedPrinter }) {
+                    selectedPrinter = list.first { $0.isDefault }?.name
+                        ?? list.first?.name ?? ""
+                }
+                await reloadSelectedCapabilities()
+            } catch {
+                printNotice = "Could not list printers: \(error.localizedDescription)"
+                printNoticeIsError = true
+            }
+        }
+    }
+
+    /// Capabilities for `selectedPrinter` — trays / media / sizes feed
+    /// the selects.
+    func reloadSelectedCapabilities() async {
+        guard !selectedPrinter.isEmpty else {
+            printerCaps = PrinterCapabilities()
+            return
+        }
+        do {
+            printerCaps = try await environment.cupsService
+                .capabilities(for: selectedPrinter)
+            // Default selections only when the captured options didn't
+            // already pin them (Preferences round-trip wins).
+            if selectedMediaType == nil {
+                selectedMediaType = printerCaps.mediaTypes.first?.id
+            }
+            if selectedTray == nil {
+                selectedTray = printerCaps.trays.first?.id
+            }
+        } catch {
+            printerCaps = PrinterCapabilities()
+        }
+    }
+
+    /// `#btnPrinterProperties` — bound NSPrintPanel ("Use Settings").
+    /// Cancel → info notice, never an error, cache untouched. On OK the
+    /// captured options are stored per-queue; a panel-side queue switch
+    /// updates `printerSelect` when the returned CUPS id is in the list.
+    func openPrinterPreferences() {
+        guard !selectedPrinter.isEmpty else { return }
+        let queue = selectedPrinter
+        let displayName = printers.first { $0.name == queue }?.displayName
+        let cups = environment.cupsService
+        Task { @MainActor in
+            do {
+                guard let result = try await PrintPanelService()
+                    .showProperties(
+                        queue: queue, displayName: displayName,
+                        cupsService: cups)
+                else {
+                    printNotice = "Printer properties dialog cancelled."
+                    printNoticeIsError = false
+                    return
+                }
+                if let selected = result.selectedPrinter,
+                   printers.contains(where: { $0.name == selected }),
+                   selected != queue {
+                    selectedPrinter = selected
+                    await reloadSelectedCapabilities()
+                }
+                if let captured = result.options.cupsOptions {
+                    capturedCupsOptions[selectedPrinter] = captured
+                }
+                if let media = result.options.mediaType {
+                    selectedMediaType = media
+                }
+                printNotice = "Settings captured for \(selectedPrinter)."
+                printNoticeIsError = false
+            } catch {
+                printNotice = error.localizedDescription
+                printNoticeIsError = true
+            }
+        }
+    }
+
+    /// `#btnPrintAll` — spool every gallery TIFF, sequentially. Stops on
+    /// the first failure so the user sees which page failed.
+    func printAllPages() {
+        guard let result = printtargResult, !isPrinting else { return }
+        isPrinting = true
+        Task { @MainActor in
+            var printed = 0
+            for page in result.pages {
+                do {
+                    try await spool(page, index: page.index)
+                    printed += 1
+                } catch {
+                    printNotice = "Print failed on \(page.page.filename): "
+                        + error.localizedDescription
+                    printNoticeIsError = true
+                    isPrinting = false
+                    return
+                }
+            }
+            printNotice = "Sent \(printed) page(s) to \(selectedPrinter)."
+            printNoticeIsError = false
+            isPrinting = false
+        }
+    }
+
+    /// `#btnPrintPage-N` — one TIFF.
+    func printPage(_ page: GalleryPage) {
+        guard !isPrinting else { return }
+        isPrinting = true
+        Task { @MainActor in
+            do {
+                try await spool(page, index: page.index)
+                printNotice = "Sent \(page.page.filename) to \(selectedPrinter)."
+                printNoticeIsError = false
+            } catch {
+                printNotice = "Print failed: \(error.localizedDescription)"
+                printNoticeIsError = true
+            }
+            isPrinting = false
+        }
+    }
+
+    private func spool(_ page: GalleryPage, index: Int) async throws {
+        guard !selectedPrinter.isEmpty else {
+            throw CupsError.noPrinterSelected
+        }
+        let options = PrintOptions(
+            orientation: printOrientation,
+            paperSize: pageSize == .custom ? nil : pageSize.rawValue,
+            mediaType: selectedMediaType,
+            ppdUncorrectedPassthrough: true,
+            cupsOptions: capturedCupsOptions[selectedPrinter])
+        try await environment.cupsService.printTarget(
+            queue: selectedPrinter,
+            tiffPath: page.fileURL.path,
+            options: options,
+            page: index)
+        // For Stage 5 history (#95): record which queue printed.
+        wizard.printerName = selectedPrinter
+    }
+
+    // MARK: - Presets
+
+    func reloadPresets() {
+        presets = environment.presetStore.all()
+    }
+
+    /// Applies every Stage 1/2 field of the preset to the live form
+    /// (bidirectional — the draft preset's dpi=150 must be visible).
+    func applyPreset(_ preset: ProfilingPreset) {
+        colourSpace = preset.colourSpace == "cmyk" ? .cmyk : .rgb
+        patchPreset = PatchCountPreset(rawValue: "\(preset.patchCount)") ?? .custom
+        customPatchCount = preset.patchCount
+        whitePatches = preset.whitePatches
+        blackPatches = preset.blackPatches
+        greySteps = preset.greySteps ?? 5; greyStepsEnabled = preset.greySteps != nil
+        singleChannelSteps = preset.singleChannelSteps ?? 5
+        singleChannelEnabled = preset.singleChannelSteps != nil
+        neutralSteps = preset.neutralSteps ?? 3
+        neutralStepsEnabled = preset.neutralSteps != nil
+        neutralConcentration = preset.neutralConcentration ?? 0.50
+        neutralConcEnabled = preset.neutralConcentration != nil
+        preconditioningProfile = preset.preconditioningProfile
+        highQuality = preset.ofpsHighQuality == true
+        adaptation = preset.ofpsAdaptation ?? 0.10
+        adaptationEnabled = preset.ofpsAdaptation != nil
+        algorithm = preset.fullSpreadAlgorithm
+            .flatMap { FullSpreadAlgorithm(presetValue: $0) } ?? .ofps
+        totalInkLimit = preset.totalInkLimit ?? 320
+        inkLimitEnabled = preset.totalInkLimit != nil
+        darkEmphasis = preset.darkEmphasis ?? 1.0
+        darkEmphasisEnabled = preset.darkEmphasis != nil
+        devicePower = preset.devicePower ?? 1.0
+        devicePowerEnabled = preset.devicePower != nil
+
+        instrument = PrintInstrument(rawValue: preset.instrument) ?? .i1
+        if let size = PageSize(rawValue: preset.pageSize) {
+            pageSize = size
+        } else if let (w, h) = Self.parseCustomPage(preset.pageSize) {
+            pageSize = .custom; customPageW = w; customPageH = h
+        } else {
+            pageSize = .a4
+        }
+        bitDepth = preset.bitDepth == 16 ? .sixteen : .eight
+        tiffDpi = preset.dpi
+        if preset.noRandomize == true {
+            layoutOrder = .raster
+        } else if (preset.randomSeed ?? 1) == 1 {
+            layoutOrder = .deterministic
+        } else {
+            layoutOrder = .customSeed
+        }
+        customSeed = preset.randomSeed ?? 1
+
+        profile.applyPreset(preset)
+
+        selectedPresetID = preset.id
+    }
+
+    /// Snapshot of the live Stage 1/2 form as a custom preset.
+    func saveCurrentAsPreset() {
+        let name = savePresetName.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !name.isEmpty else {
+            wizard.showNotice("Preset needs a name.", kind: .warning)
+            return
+        }
+        let preset = ProfilingPreset(
+            id: "custom-\(UUID().uuidString.lowercased())",
+            name: name,
+            description: savePresetDesc.trimmingCharacters(in: .whitespacesAndNewlines),
+            colourSpace: colourSpace == .cmyk ? "cmyk" : "rgb",
+            patchCount: effectivePatchCount,
+            whitePatches: whitePatches,
+            blackPatches: blackPatches,
+            greySteps: greyStepsEnabled ? greySteps : nil,
+            singleChannelSteps: singleChannelEnabled ? singleChannelSteps : nil,
+            neutralSteps: neutralStepsEnabled ? neutralSteps : nil,
+            neutralConcentration: neutralConcEnabled ? neutralConcentration : nil,
+            preconditioningProfile: preconditioningProfile,
+            ofpsHighQuality: highQuality ? true : nil,
+            ofpsAdaptation: adaptationEnabled ? adaptation : nil,
+            fullSpreadAlgorithm: algorithm.presetValue,
+            totalInkLimit: inkLimitEnabled ? totalInkLimit : nil,
+            darkEmphasis: darkEmphasisEnabled ? darkEmphasis : nil,
+            devicePower: devicePowerEnabled ? devicePower : nil,
+            instrument: instrument.rawValue,
+            pageSize: pageSize == .custom
+                ? "\(Int(customPageW))x\(Int(customPageH))"
+                : pageSize.rawValue,
+            bitDepth: bitDepth.rawValue,
+            dpi: tiffDpi,
+            randomSeed: layoutOrder == .deterministic ? 1 : customSeed,
+            noRandomize: layoutOrder == .raster,
+            calibrationFile: profile.calibrationFile.isEmpty ? nil : profile.calibrationFile,
+            applyCalibration: profile.applyCalibration ? true : nil,
+            colprofAlgorithm: profile.algorithm,
+            colprofQuality: profile.quality,
+            colprofIntent: profile.intent.isEmpty ? nil : profile.intent,
+            colprofFwa: profile.fwaValue,
+            colprofIlluminant: profile.illuminant.isEmpty ? nil : profile.illuminant,
+            colprofObserver: profile.observer.isEmpty ? nil : profile.observer,
+            colprofInputViewingCond: profile.inputViewingCond.isEmpty ? nil : profile.inputViewingCond,
+            colprofOutputViewingCond: profile.outputViewingCond.isEmpty ? nil : profile.outputViewingCond
+        )
+        do {
+            try environment.presetStore.saveCustom(preset)
+            reloadPresets()
+            selectedPresetID = preset.id
+            showingSavePreset = false
+            savePresetName = ""
+            savePresetDesc = ""
+            wizard.showNotice("Preset saved: \(preset.name)")
+        } catch {
+            wizard.showNotice(
+                "Could not save preset: \(error.localizedDescription)", kind: .error)
+        }
+    }
+
+    func deletePreset(_ preset: ProfilingPreset) {
+        do {
+            if try environment.presetStore.deleteCustom(id: preset.id) {
+                if selectedPresetID == preset.id { selectedPresetID = "none" }
+                reloadPresets()
+            } else {
+                wizard.showNotice("Built-in presets cannot be deleted.", kind: .warning)
+            }
+        } catch {
+            wizard.showNotice(
+                "Could not delete preset: \(error.localizedDescription)", kind: .error)
+        }
+    }
+
+    func importPreset() {
+        let url = UITestHooks.isEnabled
+            ? UITestHooks.presetImportURL
+            : fileDialogs.selectPresetFile()
+        guard let url else { return }
+        do {
+            let data = try Data(contentsOf: url)
+            let preset = try environment.presetStore.import(data)
+            try environment.presetStore.saveCustom(preset)
+            reloadPresets()
+            selectedPresetID = preset.id
+            wizard.showNotice("Preset imported: \(preset.name)")
+        } catch {
+            wizard.showNotice(
+                "Import failed: \(error.localizedDescription)", kind: .error)
+        }
+    }
+
+    func exportPreset(_ preset: ProfilingPreset) {
+        let url = UITestHooks.isEnabled
+            ? UITestHooks.presetExportURL
+            : fileDialogs.selectPresetSavePath(name: preset.id)
+        guard let url else { return }
+        do {
+            try environment.presetStore.export(preset)
+                .write(to: url, options: .atomic)
+            wizard.showNotice("Preset exported: \(url.lastPathComponent)")
+        } catch {
+            wizard.showNotice(
+                "Export failed: \(error.localizedDescription)", kind: .error)
+        }
+    }
+
+    static func parseCustomPage(_ raw: String) -> (Double, Double)? {
+        let parts = raw.lowercased().split(separator: "x")
+        guard parts.count == 2,
+              let w = Double(parts[0]), let h = Double(parts[1]),
+              w >= 50, h >= 50 else { return nil }
+        return (w, h)
+    }
+}

Sources/ICCery/WizardViewModel.swift

@@ -2,44 +2,142 @@ import Foundation
 import Observation
 import ICCeryCore
 
-/// Wizard shell state (issue #1). Artefact gating, persistence and the
-/// "open existing" flow land in issue #4.
+/// Wizard state machine + artefact gating (issue #4, docs/06).
+///
+/// `wizardState` fields (`currentStage`, `basename`, `cwd`,
+/// `printerName`, `sessionMode`, `profileBasename`) are persisted to
+/// `wizard_state.json`; unlocks come from `ArtefactProbe.verify` —
+/// navigation is disk, not buttons.
 @MainActor
 @Observable
 final class WizardViewModel {
-    /// Currently displayed stage.
-    var stage: WizardStage = .generate
+
+    // MARK: - wizardState fields (persisted)
+
+    var stage: WizardStage {
+        didSet { if stage != oldValue { persist() } }
+    }
+    /// `wizardState.basename` — empty until a real artefact names it (#60).
+    var basename: String {
+        didSet { if basename != oldValue { refreshGating(); persist() } }
+    }
+    /// `wizardState.cwd` — resolved via `resolveSafeCwd` (#59).
+    var workingDirectory: URL? {
+        didSet { if workingDirectory != oldValue { refreshGating(); persist() } }
+    }
+    var printerName: String? {
+        didSet { if printerName != oldValue { persist() } }
+    }
+    var sessionMode: SessionMode {
+        didSet { if sessionMode != oldValue { persist() } }
+    }
+    /// `profileBasename` may differ after a `.ti3` import (#94).
+    var profileBasename: String? {
+        didSet { if profileBasename != oldValue { persist() } }
+    }
+
+    // MARK: - Ephemeral
 
     /// Banner notice currently displayed (`#wizardNotification`).
     var notice: Notice?
+    /// Current artefact probe result; recomputed on `refreshGating()`.
+    private(set) var artefacts = StageArtefacts()
 
-    /// Target basename shared across stages (`targetBasename`).
-    var basename: String = ""
-
-    /// Working directory for all Argyll artefacts.
-    var workingDirectory: URL?
-
-    /// Printer queue selected in Stage 2; retained across stages.
-    var printerName: String?
-
+    private let stateStore: WizardStateStore
     private var noticeDismissTask: Task<Void, Never>?
 
-    /// `true` while Stage 0 (printer calibration) is shown instead of a
-    /// stepper stage.
+    init(stateStore: WizardStateStore = WizardStateStore()) {
+        self.stateStore = stateStore
+        let s = stateStore.load()
+        self.stage = s.stage
+        self.basename = s.basename
+        self.workingDirectory = s.cwd.isEmpty ? nil : URL(fileURLWithPath: s.cwd)
+        self.printerName = s.printerName
+        self.sessionMode = s.sessionMode
+        self.profileBasename = s.profileBasename
+        refreshGating()
+        // A restored stage may have been locked since (#151).
+        if !WizardGating.isUnlocked(stage, artefacts: artefacts), stage != .calibrate {
+            stage = WizardGating.deepestUnlocked(artefacts: artefacts)
+        }
+    }
+
+    // MARK: - Gating
+
+    /// `isUnlocked` for the sidebar stepper.
+    func isUnlocked(_ stage: WizardStage) -> Bool {
+        WizardGating.isUnlocked(stage, artefacts: artefacts)
+    }
+
+    /// `true` while Stage 0 (printer calibration) is shown.
     var isCalibrating: Bool { stage == .calibrate }
 
-    func go(to stage: WizardStage) {
-        self.stage = stage
+    /// Re-probes the artefact directory and re-locks (#151). Called on
+    /// window focus, stage entry, and basename/cwd changes.
+    func refreshGating() {
+        guard !basename.isEmpty, let dir = effectiveWorkingDirectory else {
+            artefacts = StageArtefacts()
+            return
+        }
+        artefacts = ArtefactProbe.verify(basename: basename, cwd: dir)
+    }
+
+    /// `setTarget(basename, cwd)` — validates the basename (no `/`, `\`,
+    /// `..`; no placeholders — #60) and resolves the cwd (#59).
+    func setTarget(basename: String, workingDirectory: URL?) {
+        do {
+            self.basename = try PathSecurity.sanitizeBasename(basename)
+        } catch {
+            showNotice("Invalid target name.", kind: .error)
+            return
+        }
+        self.workingDirectory = PathSecurity.resolveSafeCwd(workingDirectory)
+    }
+
+    /// cwd never stays empty once a basename exists (#59).
+    var effectiveWorkingDirectory: URL? {
+        if let workingDirectory { return workingDirectory }
+        return basename.isEmpty ? nil : PathSecurity.resolveSafeCwd(nil)
+    }
+
+    // MARK: - Navigation
+
+    /// `navigateToStage(n)` — refuses locked forward moves with a
+    /// warning banner; backward is always allowed (docs/06).
+    func go(to target: WizardStage) {
+        guard target != .calibrate else { enterCalibration(); return }
+        if WizardGating.canNavigate(to: target, from: stage, artefacts: artefacts) {
+            stage = target
+        } else {
+            showNotice(
+                "Stage \(target.stepperIndex ?? 0) is locked — the required artefact is missing.",
+                kind: .warning
+            )
+        }
     }
 
     func enterCalibration() {
+        sessionMode = .calibration
         stage = .calibrate
     }
 
     func exitCalibration() {
+        sessionMode = .profile
         stage = .generate
     }
 
+    /// Window-focus hook (#151): files deleted in Finder re-lock stages.
+    /// If the current stage re-locked, fall back to the deepest unlocked.
+    func windowDidBecomeKey() {
+        refreshGating()
+        if stage != .calibrate,
+           !WizardGating.isUnlocked(stage, artefacts: artefacts) {
+            stage = WizardGating.deepestUnlocked(artefacts: artefacts)
+        }
+    }
+
+    // MARK: - Notice
+
     func showNotice(_ text: String, kind: Notice.Kind = .info, autoHideAfter: TimeInterval? = 6) {
         noticeDismissTask?.cancel()
         let notice = Notice(kind: kind, text: text, autoHideAfter: autoHideAfter)
@@ -59,4 +157,18 @@ final class WizardViewModel {
         noticeDismissTask?.cancel()
         notice = nil
     }
+
+    // MARK: - Persistence
+
+    private func persist() {
+        let state = WizardState(
+            currentStage: stage.rawValue,
+            basename: basename,
+            cwd: workingDirectory?.path ?? "",
+            printerName: printerName,
+            sessionMode: sessionMode,
+            profileBasename: profileBasename
+        )
+        try? stateStore.save(state)
+    }
 }

Tests/ICCeryCoreTests/ApplycalArgsTests.swift

@@ -0,0 +1,30 @@
+import Foundation
+import Testing
+@testable import ICCeryCore
+
+@Suite("ApplycalArgs")
+struct ApplycalArgsTests {
+
+    @Test("Apply argv")
+    func applyArgv() throws {
+        let config = ApplycalConfig(
+            calibrationPath: "/tmp/cal.cal",
+            inputProfileURL: URL(fileURLWithPath: "/tmp/profile.icc")
+        )
+        let args = try ApplycalArgs.build(config: config)
+        #expect(args == ["-v", "-a", "/tmp/cal.cal", "/tmp/profile.icc"])
+    }
+
+    @Test("Unapply is emitted when the caller explicitly sets it")
+    func unapplyEmittedWhenConfigSet() throws {
+        let config = ApplycalConfig(
+            calibrationPath: "/tmp/cal.cal",
+            inputProfileURL: URL(fileURLWithPath: "/tmp/profile.icc"),
+            unapply: true
+        )
+        let args = try ApplycalArgs.build(config: config)
+        // Builder emits -u only when the caller explicitly sets unapply.
+        // The UI layer never passes unapply: true in v2.0.
+        #expect(args == ["-v", "-u", "/tmp/cal.cal", "/tmp/profile.icc"])
+    }
+}

Tests/ICCeryCoreTests/ArgyllRunnerColprofTests.swift

@@ -0,0 +1,52 @@
+import Foundation
+import Testing
+@testable import ICCeryCore
+
+final class LogHolder: @unchecked Sendable {
+    private let lock = NSLock()
+    private var _lines: [String] = []
+
+    func append(_ batch: [String]) {
+        lock.lock()
+        _lines.append(contentsOf: batch)
+        lock.unlock()
+    }
+
+    var lines: [String] {
+        lock.lock()
+        defer { lock.unlock() }
+        return _lines
+    }
+}
+
+@Suite("ArgyllRunner colprof")
+struct ArgyllRunnerColprofTests {
+
+    @Test("Mock colprof produces .icc")
+    func colprofProducesIcc() async throws {
+        let binDir = URL(fileURLWithPath: #filePath)
+            .deletingLastPathComponent()
+            .deletingLastPathComponent()
+            .appendingPathComponent("ICCeryUITests/Fixtures/bin")
+        let testRoot = FileManager.default.temporaryDirectory
+            .appendingPathComponent("colprof-test-\(UUID().uuidString)")
+        try FileManager.default.createDirectory(at: testRoot, withIntermediateDirectories: true)
+
+        let runner = ArgyllRunner(
+            processManager: .shared,
+            binaryResolver: BinaryResolver(overrideDir: binDir)
+        )
+
+        let holder = LogHolder()
+        let config = ColprofConfig(basename: "testrun", workingDirectory: testRoot)
+        let url = try await runner.runColprof(config: config) { batch in
+            holder.append(batch)
+        }
+
+        #expect(url.lastPathComponent == "testrun.icc")
+        #expect(FileManager.default.fileExists(atPath: url.path))
+        #expect(holder.lines.contains { $0.contains("Gamut mapping") })
+
+        try? FileManager.default.removeItem(at: testRoot)
+    }
+}

Tests/ICCeryCoreTests/ArtefactFilesTests.swift

@@ -0,0 +1,124 @@
+import Testing
+import Foundation
+import ImageIO
+import UniformTypeIdentifiers
+@testable import ICCeryCore
+
+private func tempURL(_ name: String) -> URL {
+    FileManager.default.temporaryDirectory
+        .appendingPathComponent("iccery-af-\(UUID().uuidString)")
+        .appendingPathComponent(name)
+}
+
+@Suite("Ti2Header")
+struct Ti2HeaderTests {
+    @Test func parsesKeywordsAndSibling() throws {
+        let dir = FileManager.default.temporaryDirectory
+            .appendingPathComponent("iccery-ti2-\(UUID().uuidString)")
+        try FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)
+        try """
+        CTI2
+        TARGET_INSTRUMENT "i1iO"
+        NUMBER_OF_FIELDS 9
+        NUMBER_OF_SETS 800
+        NUMBER_OF_PAGES 3
+        BEGIN_DATA_FORMAT
+        SAMPLE_ID RGB_R
+        END_DATA_FORMAT
+        """.write(to: dir.appendingPathComponent("job.ti2"), atomically: true, encoding: .utf8)
+        try "CGATS".write(
+            to: dir.appendingPathComponent("job.ti1"), atomically: true, encoding: .utf8
+        )
+
+        let h = Ti2Header.parse(dir.appendingPathComponent("job.ti2"))
+        #expect(h.instrument == "i1iO")
+        #expect(h.patchCount == 800)
+        #expect(h.pageCount == 3)
+        #expect(h.hasSiblingTi1)
+    }
+
+    @Test func missingFileYieldsEmptyHeader() {
+        let h = Ti2Header.parse(URL(fileURLWithPath: "/nonexistent/x.ti2"))
+        #expect(h.instrument == nil && h.patchCount == nil && !h.hasSiblingTi1)
+    }
+
+    @Test func numberOfFieldsIsNotPatchCount() throws {
+        let url = tempURL("t.ti2")
+        try FileManager.default.createDirectory(
+            at: url.deletingLastPathComponent(), withIntermediateDirectories: true
+        )
+        try "NUMBER_OF_FIELDS 9\nNUMBER_OF_SETS 52\nBEGIN_DATA\n".write(
+            to: url, atomically: true, encoding: .utf8
+        )
+        #expect(Ti2Header.parse(url).patchCount == 52)
+    }
+}
+
+@Suite("TiffPreview")
+struct TiffPreviewTests {
+    /// Builds a real 2000×1000 TIFF in a temp dir via ImageIO.
+    private func makeTiff(width: Int = 2000, height: Int = 1000) throws -> URL {
+        let url = tempURL("big.tif")
+        try FileManager.default.createDirectory(
+            at: url.deletingLastPathComponent(), withIntermediateDirectories: true
+        )
+        let colorSpace = CGColorSpace(name: CGColorSpace.sRGB)!
+        let ctx = CGContext(
+            data: nil, width: width, height: height,
+            bitsPerComponent: 8, bytesPerRow: width * 4,
+            space: colorSpace,
+            bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
+        )!
+        ctx.setFillColor(CGColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 1))
+        ctx.fill(CGRect(x: 0, y: 0, width: width, height: height))
+        let image = ctx.makeImage()!
+
+        guard let dest = CGImageDestinationCreateWithURL(
+            url as CFURL, UTType.tiff.identifier as CFString, 1, nil
+        ) else { throw CocoaError(.fileWriteUnknown) }
+        CGImageDestinationAddImage(dest, image, nil)
+        guard CGImageDestinationFinalize(dest) else { throw CocoaError(.fileWriteUnknown) }
+        return url
+    }
+
+    @Test func producesCappedPNG() throws {
+        let tiff = try makeTiff()
+        let png = TiffPreview.previewPNG(tiff: tiff)
+        #expect(png != nil)
+        // PNG magic
+        #expect(png!.prefix(8) == Data([0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A]))
+        // Verify the cap by decoding the thumbnail header.
+        let src = CGImageSourceCreateWithData(png! as CFData, nil)!
+        let img = CGImageSourceCreateImageAtIndex(src, 0, nil)!
+        #expect(max(img.width, img.height) <= TiffPreview.maxEdge)
+        #expect(img.width == 1200)
+    }
+
+    @Test func nonTiffReturnsNil() throws {
+        let url = tempURL("not-tiff.txt")
+        try FileManager.default.createDirectory(
+            at: url.deletingLastPathComponent(), withIntermediateDirectories: true
+        )
+        try "hello".write(to: url, atomically: true, encoding: .utf8)
+        #expect(TiffPreview.previewPNG(tiff: url) == nil)
+    }
+}
+
+@Suite("ArtefactFiles")
+struct ArtefactFilesTests {
+    @Test func base64RoundTrip() throws {
+        let url = tempURL("a.txt")
+        try FileManager.default.createDirectory(
+            at: url.deletingLastPathComponent(), withIntermediateDirectories: true
+        )
+        try "hello".write(to: url, atomically: true, encoding: .utf8)
+        let b64 = try ArtefactFiles.readBase64(url)
+        #expect(Data(base64Encoded: b64) == Data("hello".utf8))
+    }
+
+    @Test func defaultWorkingDirExists() {
+        #expect(FileManager.default.fileExists(
+            atPath: ArtefactFiles.defaultWorkingDirectory().path
+        ))
+    }
+}

Tests/ICCeryCoreTests/BinaryResolverTests.swift

@@ -0,0 +1,83 @@
+import Testing
+import Foundation
+@testable import ICCeryCore
+
+@Suite("BinaryResolver")
+struct BinaryResolverTests {
+
+    private func makeTree(_ body: (URL) throws -> Void) throws -> URL {
+        let root = FileManager.default.temporaryDirectory
+            .appendingPathComponent("iccery-resolver-\(UUID().uuidString)")
+        try FileManager.default.createDirectory(at: root, withIntermediateDirectories: true)
+        try body(root)
+        return root
+    }
+
+    private func touch(_ url: URL, executable: Bool = true) throws {
+        FileManager.default.createFile(atPath: url.path, contents: Data())
+        if executable {
+            try FileManager.default.setAttributes(
+                [.posixPermissions: 0o755], ofItemAtPath: url.path
+            )
+        }
+    }
+
+    @Test func overrideDirWinsWhenFileExists() throws {
+        let override = try makeTree { root in
+            try touch(root.appendingPathComponent("targen"))
+        }
+        let bundled = try makeTree { _ in }
+        let r = BinaryResolver(bundledRoot: bundled, overrideDir: override)
+        #expect(r.resolve("targen") == override.appendingPathComponent("targen"))
+    }
+
+    @Test func overrideFallsThroughWhenMissing() throws {
+        let override = try makeTree { _ in }
+        let bundled = try makeTree { root in
+            let dir = root.appendingPathComponent("macos-universal")
+            try FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)
+            try touch(dir.appendingPathComponent("instlist"))
+        }
+        let r = BinaryResolver(bundledRoot: bundled, overrideDir: override)
+        #expect(r.resolve("targen").path.contains("macos-universal/targen"))
+    }
+
+    @Test func universalPreferredWhenMarkerPresent() throws {
+        let bundled = try makeTree { root in
+            for dir in ["macos-universal", "macos-x86_64"] {
+                let d = root.appendingPathComponent(dir)
+                try FileManager.default.createDirectory(at: d, withIntermediateDirectories: true)
+                try touch(d.appendingPathComponent("instlist"))
+            }
+        }
+        let r = BinaryResolver(bundledRoot: bundled)
+        #expect(r.platformDir() == "macos-universal")
+    }
+
+    @Test func fallsBackToArchDir() throws {
+        let bundled = try makeTree { root in
+            let d = root.appendingPathComponent("macos-x86_64")
+            try FileManager.default.createDirectory(at: d, withIntermediateDirectories: true)
+            try touch(d.appendingPathComponent("instlist"))
+        }
+        let r = BinaryResolver(
+            bundledRoot: bundled,
+            archDirs: ["macos-universal", "macos-x86_64"]
+        )
+        #expect(r.platformDir() == "macos-x86_64")
+    }
+
+    @Test func missingEverythingReturnsConstructedPath() throws {
+        let bundled = try makeTree { _ in }
+        let r = BinaryResolver(bundledRoot: bundled)
+        // v1 semantic: path is returned; spawn surfaces the error.
+        #expect(r.resolve("targen").path.hasSuffix("macos-universal/targen"))
+        #expect(!r.exists(r.resolve("targen")))
+    }
+
+    @Test func mockAndGamutPaths() throws {
+        let r = BinaryResolver(bundledRoot: URL(fileURLWithPath: "/x"))
+        #expect(r.mock("chartread").path == "/x/mocks/chartread.mock")
+        #expect(r.referenceGamut("sRGB.gam").path == "/x/reference_gamuts/sRGB.gam")
+    }
+}

Tests/ICCeryCoreTests/CGATSParserTests.swift

@@ -0,0 +1,134 @@
+import Foundation
+import Testing
+@testable import ICCeryCore
+
+@Suite("CGATS Parser & Writer")
+struct CGATSParserTests {
+
+    private static let canonicalCTI3 = """
+    CTI3
+    DESCRIPTOR "Sample target"
+    COLOR_REP "RGB"
+    DEVICE_CLASS "DISPLAY"
+    NUMBER_OF_FIELDS 11
+    NUMBER_OF_SETS 2
+    BEGIN_DATA_FORMAT
+    SAMPLE_ID\tSAMPLE_LOC\tRGB_R\tRGB_G\tRGB_B\tXYZ_X\tXYZ_Y\tXYZ_Z\tLAB_L\tLAB_A\tLAB_B
+    END_DATA_FORMAT
+    BEGIN_DATA
+    1\tA1\t50.0\t0.0\t0.0\t20.0\t10.0\t5.0\t50.0\t60.0\t30.0
+    2\tA2\t0.0\t50.0\t0.0\t10.0\t30.0\t5.0\t60.0\t-50.0\t40.0
+    END_DATA
+    """
+
+    @Test("Parses CTI3 with canonical field names")
+    func parseCTI3() throws {
+        let dataset = try CGATSParser.parse(Self.canonicalCTI3)
+        #expect(dataset.format == .cti3)
+        #expect(dataset.samples.count == 2)
+        #expect(dataset.colorRep == "RGB")
+        #expect(dataset.deviceClass == "DISPLAY")
+        #expect(dataset.samples[0].id == "1")
+        #expect(dataset.samples[0].loc == "A1")
+        #expect(dataset.samples[1].values["RGB_G"] == "50.0000")
+    }
+
+    @Test("Round-trips parse, write, reparse")
+    func roundTrip() throws {
+        let first = try CGATSParser.parse(Self.canonicalCTI3)
+        let text = try CGATSWriter.write(first)
+        let second = try CGATSParser.parse(text)
+        #expect(second.format == first.format)
+        #expect(second.samples.count == first.samples.count)
+        #expect(second.colorRep == first.colorRep)
+        #expect(second.deviceClass == first.deviceClass)
+    }
+
+    @Test("Parses CSV with comma delimiters")
+    func parseCSV() throws {
+        let csv = """
+        SAMPLE_ID,SAMPLE_LOC,RGB_R,RGB_G,RGB_B,XYZ_X,XYZ_Y,XYZ_Z,LAB_L,LAB_A,LAB_B
+        1,A1,50,0,0,20,10,5,50,60,30
+        2,A2,0,50,0,10,30,5,60,-50,40
+        """
+        let dataset = try CGATSParser.parse(csv, sourceURL: URL(fileURLWithPath: "/tmp/sample.csv"))
+        #expect(dataset.format == .csv)
+        #expect(dataset.samples.count == 2)
+        #expect(dataset.samples[0].values["RGB_R"] == "50.0000")
+    }
+
+    @Test("Converts 0-255 device values to 0-100")
+    func converts255To100() throws {
+        let rgb = """
+        CTI3
+        COLOR_REP RGB
+        NUMBER_OF_FIELDS 6
+        NUMBER_OF_SETS 1
+        BEGIN_DATA_FORMAT
+        SAMPLE_ID RGB_R RGB_G RGB_B XYZ_X XYZ_Y
+        END_DATA_FORMAT
+        BEGIN_DATA
+        1 255 128 0 50 25
+        END_DATA
+        """
+        let dataset = try CGATSParser.parse(rgb)
+        #expect(dataset.samples[0].values["RGB_R"] == "100.0000")
+        #expect(dataset.samples[0].values["RGB_G"] == "50.1961")
+    }
+
+    @Test("Synthesizes COLOR_REP and DEVICE_CLASS when missing")
+    func synthesizesMetadata() throws {
+        let cmyk = """
+        CTI3
+        NUMBER_OF_FIELDS 6
+        NUMBER_OF_SETS 1
+        BEGIN_DATA_FORMAT
+        SAMPLE_ID CMYK_C CMYK_M CMYK_Y CMYK_K LAB_L
+        END_DATA_FORMAT
+        BEGIN_DATA
+        1 50 50 50 50 50
+        END_DATA
+        """
+        let dataset = try CGATSParser.parse(cmyk)
+        #expect(dataset.colorRep == "CMYK")
+        #expect(dataset.deviceClass == "PRINTER")
+    }
+
+    @Test("Rejects empty file")
+    func rejectsEmpty() {
+        #expect(throws: (any Error).self) {
+            _ = try CGATSParser.parse("")
+        }
+    }
+
+    @Test("Rejects malformed arity")
+    func rejectsArity() {
+        let bad = """
+        CTI3
+        NUMBER_OF_FIELDS 2
+        NUMBER_OF_SETS 1
+        BEGIN_DATA_FORMAT
+        SAMPLE_ID RGB_R
+        END_DATA_FORMAT
+        BEGIN_DATA
+        1
+        END_DATA
+        """
+        #expect(throws: (any Error).self) {
+            _ = try CGATSParser.parse(bad)
+        }
+    }
+
+    @Test("Writer emits valid .ti3 with tabs and required keywords")
+    func writerFormat() throws {
+        let dataset = try CGATSParser.parse(Self.canonicalCTI3)
+        let text = try CGATSWriter.write(dataset)
+        #expect(text.contains("CTI3"))
+        #expect(text.contains("BEGIN_DATA_FORMAT"))
+        #expect(text.contains("BEGIN_DATA"))
+        #expect(text.contains("END_DATA"))
+        #expect(text.contains("COLOR_REP"))
+        #expect(text.contains("DEVICE_CLASS"))
+        #expect(text.contains("\t"))
+    }
+}

Tests/ICCeryCoreTests/ColprofArgsTests.swift

@@ -0,0 +1,72 @@
+import Foundation
+import Testing
+@testable import ICCeryCore
+
+@Suite("ColprofArgs")
+struct ColprofArgsTests {
+
+    @Test("Default algorithm and quality")
+    func defaults() throws {
+        let config = ColprofConfig(basename: "target")
+        let args = try ColprofArgs.build(config: config)
+        #expect(args == ["-v", "-a", "l", "-q", "m", "target"])
+    }
+
+    @Test("FWA bare -f when empty string")
+    func fwaBareFlag() throws {
+        let config = ColprofConfig(fwa: "", basename: "target")
+        let args = try ColprofArgs.build(config: config)
+        #expect(args == ["-v", "-a", "l", "-q", "m", "-f", "target"])
+    }
+
+    @Test("FWA D50 and D65 emit -f value")
+    func fwaD50() throws {
+        let config = ColprofConfig(fwa: "D50", basename: "target")
+        let args = try ColprofArgs.build(config: config)
+        #expect(args.contains("-f"))
+        #expect(args.contains("D50"))
+        #expect(args.last == "target")
+    }
+
+    @Test("FWA none is omitted")
+    func fwaNoneOmitted() throws {
+        let config = ColprofConfig(fwa: "none", basename: "target")
+        let args = try ColprofArgs.build(config: config)
+        #expect(!args.contains("-f"))
+    }
+
+    @Test("Viewing conditions skip none")
+    func viewingCondNoneSkipped() throws {
+        let config = ColprofConfig(
+            inputViewingCond: "none",
+            outputViewingCond: "mt",
+            basename: "target"
+        )
+        let args = try ColprofArgs.build(config: config)
+        #expect(!args.contains("-c"))
+        #expect(args.contains("-d"))
+        #expect(args.contains("mt"))
+    }
+
+    @Test("Description falls back to basename when empty")
+    func descriptionFallback() throws {
+        let config = ColprofConfig(description: "", basename: "target")
+        let args = try ColprofArgs.build(config: config)
+        #expect(!args.contains("-D"))
+    }
+
+    @Test("Copyright only when non-empty")
+    func copyright() throws {
+        let config = ColprofConfig(copyright: "Gronod 2026", basename: "target")
+        let args = try ColprofArgs.build(config: config)
+        #expect(args.contains("-C"))
+        #expect(args.contains("Gronod 2026"))
+    }
+
+    @Test("No -u passed")
+    func noProgressJsonFlag() throws {
+        let config = ColprofConfig(basename: "target")
+        let args = try ColprofArgs.build(config: config)
+        #expect(!args.contains("-u"))
+    }
+}