MacMonitor/Sources/UI/Settings/AlertsSettingsView.swift

import SwiftUI
import UserNotifications

// MARK: - Alerts Settings Pane

/// Preferences UI for threshold alert rules. Bound directly to
/// `AlertEngine.shared.configuration`, which auto-persists to `UserDefaults`.
public struct AlertsSettingsView: View {
    @Bindable private var engine = AlertEngine.shared
    @State private var authorizationStatus: UNAuthorizationStatus = .notDetermined

    public init() {}

    public var body: some View {
        Form {
            Section("Notifications") {
                Toggle("Enable Threshold Alerts", isOn: $engine.configuration.alertsEnabled)

                HStack {
                    Text("Notification Permission")
                    Spacer()
                    Text(statusText)
                        .foregroundStyle(statusColor)
                    if authorizationStatus == .notDetermined {
                        Button("Request Permission") {
                            engine.requestNotificationAuthorization()
                            refreshAuthorizationStatus()
                        }
                    } else if authorizationStatus == .denied {
                        Button("Open System Settings") {
                            if let url = URL(string: "x-apple.systempreferences:com.apple.preference.notifications") {
                                NSWorkspace.shared.open(url)
                            }
                        }
                    }
                }

                Button("Send Test Notification") {
                    engine.dispatcher.dispatch(SystemAlert(
                        id: "testNotification",
                        kind: .cpuTemperature,
                        severity: .warning,
                        title: String(localized: "MacMonitor Test Alert"),
                        message: String(localized: "Notifications are configured correctly."),
                        timestamp: Date()
                    ))
                }
                .disabled(!engine.configuration.alertsEnabled)

                Picker("Alert Cooldown", selection: $engine.configuration.cooldownMinutes) {
                    Text("1 minute").tag(1.0)
                    Text("5 minutes").tag(5.0)
                    Text("15 minutes").tag(15.0)
                    Text("30 minutes").tag(30.0)
                    Text("1 hour").tag(60.0)
                }
            }

            Section("CPU Temperature") {
                Toggle("High CPU Temperature Alert", isOn: $engine.configuration.cpuTempEnabled)
                LabeledContent("Threshold") {
                    Slider(value: $engine.configuration.cpuTempThresholdC, in: 60...110, step: 1) {
                        EmptyView()
                    }
                    Text("\(Int(engine.configuration.cpuTempThresholdC))°C")
                        .monospacedDigit()
                        .frame(width: 48, alignment: .trailing)
                }
            }

            Section("Cooling Fans") {
                Toggle("Fan Stall Alert", isOn: $engine.configuration.fanStallEnabled)
                LabeledContent("Alert when CPU above") {
                    Slider(value: $engine.configuration.fanStallTempThresholdC, in: 40...100, step: 1) {
                        EmptyView()
                    }
                    Text("\(Int(engine.configuration.fanStallTempThresholdC))°C")
                        .monospacedDigit()
                        .frame(width: 48, alignment: .trailing)
                }
                Text("Triggers when a fan reports 0 RPM while the CPU is hot.")
                    .font(.caption)
                    .foregroundStyle(.secondary)
            }

            Section("Memory") {
                Toggle("Low Memory Alert", isOn: $engine.configuration.memoryEnabled)
                LabeledContent("Free RAM below") {
                    Slider(value: $engine.configuration.memoryFreeMBThreshold, in: 100...4096, step: 50) {
                        EmptyView()
                    }
                    Text("\(Int(engine.configuration.memoryFreeMBThreshold)) MB")
                        .monospacedDigit()
                        .frame(width: 64, alignment: .trailing)
                }
                Toggle("Alert on Critical Memory Pressure", isOn: $engine.configuration.memoryAlertOnCriticalPressure)
            }

            Section("Storage") {
                Toggle("Low Disk Space Alert", isOn: $engine.configuration.storageEnabled)
                LabeledContent("Free space below") {
                    Slider(value: $engine.configuration.storageFreeGBThreshold, in: 1...100, step: 1) {
                        EmptyView()
                    }
                    Text("\(Int(engine.configuration.storageFreeGBThreshold)) GB")
                        .monospacedDigit()
                        .frame(width: 48, alignment: .trailing)
                }
                LabeledContent("Free percent below") {
                    Slider(value: $engine.configuration.storageFreePercentThreshold, in: 1...50, step: 1) {
                        EmptyView()
                    }
                    Text("\(Int(engine.configuration.storageFreePercentThreshold))%")
                        .monospacedDigit()
                        .frame(width: 48, alignment: .trailing)
                }
            }

            Section("Battery") {
                Toggle("Low Battery Alert", isOn: $engine.configuration.batteryEnabled)
                LabeledContent("Charge below") {
                    Slider(value: $engine.configuration.batteryPercentThreshold, in: 1...50, step: 1) {
                        EmptyView()
                    }
                    Text("\(Int(engine.configuration.batteryPercentThreshold))%")
                        .monospacedDigit()
                        .frame(width: 48, alignment: .trailing)
                }
                Text("Only fires while discharging on battery power.")
                    .font(.caption)
                    .foregroundStyle(.secondary)
            }
        }
        .formStyle(.grouped)
        .frame(minWidth: 480, minHeight: 520)
        .task { await refreshAuthorizationStatus() }
    }

    private var statusText: String {
        switch authorizationStatus {
        case .authorized, .provisional, .ephemeral: return "Authorized"
        case .denied: return "Denied"
        case .notDetermined: return "Not Requested"
        @unknown default: return "Unknown"
        }
    }

    private var statusColor: Color {
        switch authorizationStatus {
        case .authorized, .provisional, .ephemeral: return .green
        case .denied: return .red
        default: return .secondary
        }
    }

    private func refreshAuthorizationStatus() {
        Task {
            authorizationStatus = await engine.notificationAuthorizationStatus()
        }
    }

    private func refreshAuthorizationStatus() async {
        authorizationStatus = await engine.notificationAuthorizationStatus()
    }
}