/**
 * Shared yt-dlp stderr parsing. Used by both download.ts and probe.ts so the
 * error-extraction logic lives in one place (audit M1).
 */

/** Trim yt-dlp's noisy stderr down to the most useful trailing error line. */
export function cleanError(stderr: string): string {
  const lines = stderr
    .split('\n')
    .map((l) => l.trim())
    .filter(Boolean)
  const errLine = [...lines].reverse().find((l) => /^error/i.test(l))
  return (errLine ?? lines[lines.length - 1] ?? '').replace(/^error:\s*/i, '').trim()
}