// ── Format Utilities ───────────────────────────────────────────

/**
 * Format milliseconds as HH:MM:SS or MM:SS
 */
export function formatDuration(ms: number): string {
  if (ms <= 0) return '00:00';
  const totalSeconds = Math.floor(ms / 1000);
  const hours = Math.floor(totalSeconds / 3600);
  const minutes = Math.floor((totalSeconds % 3600) / 60);
  const seconds = totalSeconds % 60;

  const pad = (n: number) => n.toString().padStart(2, '0');

  if (hours > 0) {
    return `${pad(hours)}:${pad(minutes)}:${pad(seconds)}`;
  }
  return `${pad(minutes)}:${pad(seconds)}`;
}

/**
 * Format milliseconds as compact string: "2h 15m", "45m", "30s"
 */
export function formatDurationCompact(ms: number): string {
  if (ms <= 0) return '0s';
  const totalSeconds = Math.floor(ms / 1000);
  const hours = Math.floor(totalSeconds / 3600);
  const minutes = Math.floor((totalSeconds % 3600) / 60);
  const seconds = totalSeconds % 60;

  if (hours > 0 && minutes > 0) return `${hours}h ${minutes}m`;
  if (hours > 0) return `${hours}h`;
  if (minutes > 0 && seconds > 0 && minutes < 5) return `${minutes}m ${seconds}s`;
  if (minutes > 0) return `${minutes}m`;
  return `${seconds}s`;
}

/**
 * Format a timestamp as relative time: "in 5m", "2h ago", "now"
 */
export function formatRelativeTime(targetTime: number, now: number = Date.now()): string {
  const diff = targetTime - now;
  const absDiff = Math.abs(diff);

  if (absDiff < 30_000) return 'now';

  const compact = formatDurationCompact(absDiff);
  return diff > 0 ? `in ${compact}` : `${compact} ago`;
}

/**
 * Format time as HH:MM AM/PM
 */
export function formatTime(timestamp: number): string {
  const date = new Date(timestamp);
  return date.toLocaleTimeString('en-US', {
    hour: 'numeric',
    minute: '2-digit',
    hour12: true,
  });
}

/**
 * Format date as "Mon, Feb 27"
 */
export function formatDate(timestamp: number): string {
  const date = new Date(timestamp);
  return date.toLocaleDateString('en-US', {
    weekday: 'short',
    month: 'short',
    day: 'numeric',
  });
}