// Copyright (c) 2026 Gordon Bolton. MIT License.

export function formatSize(size) {
  if (!size) return 'N/A';
  // If already a formatted string (e.g., "21.5 GB"), return as-is
  if (typeof size === 'string') {
    return size;
  }
  // If it's a number (bytes), format it
  const sizes = ['B', 'KB', 'MB', 'GB', 'TB'];
  const i = Math.floor(Math.log(size) / Math.log(1024));
  return Math.round(size / Math.pow(1024, i) * 100) / 100 + ' ' + sizes[i];
}

export function formatSpeed(bytesPerSecond) {
  if (!bytesPerSecond || bytesPerSecond === 0) return '0 B/s';
  
  const units = ['B/s', 'KB/s', 'MB/s', 'GB/s'];
  let value = bytesPerSecond;
  let unitIndex = 0;
  
  while (value >= 1024 && unitIndex < units.length - 1) {
    value /= 1024;
    unitIndex++;
  }
  
  return `${value.toFixed(2)} ${units[unitIndex]}`;
}

export function formatDate(dateString) {
  if (!dateString) return 'N/A';
  return new Date(dateString).toLocaleString();
}

export function formatTimeAgo(timestamp) {
  if (!timestamp) return 'Never';
  const seconds = Math.floor((Date.now() - timestamp) / 1000);
  if (seconds < 60) return seconds + 's ago';
  const minutes = Math.floor(seconds / 60);
  if (minutes < 60) return minutes + 'm ago';
  const hours = Math.floor(minutes / 60);
  if (hours < 24) return hours + 'h ago';
  return Math.floor(hours / 24) + 'd ago';
}

export function escapeHtml(str) {
  const div = document.createElement('div');
  div.textContent = str;
  return div.innerHTML;
}

// Build an episode-info element for series downloads/history.
// Single episode: "S01E05 — Episode Title"
// Multiple episodes: "Multiple episodes" with tooltip listing them all.
// Returns null if no episode data.
export function formatEpisodeInfo(episodes) {
  if (!episodes || episodes.length === 0) return null;
  const el = document.createElement('p');
  el.className = 'episode-info';
  if (episodes.length === 1) {
    const ep = episodes[0];
    const code = 'S' + String(ep.season).padStart(2, '0') + 'E' + String(ep.episode).padStart(2, '0');
    el.textContent = ep.title ? code + ' \u2014 ' + ep.title : code;
  } else {
    el.textContent = 'Multiple episodes';
    el.classList.add('multi-episode');
    const lines = episodes.map(ep => {
      const code = 'S' + String(ep.season).padStart(2, '0') + 'E' + String(ep.episode).padStart(2, '0');
      return ep.title ? code + ' \u2014 ' + ep.title : code;
    });
    el.setAttribute('data-tooltip', lines.join('\n'));
  }
  return el;
}