import { execFile } from 'child_process'
import { existsSync } from 'fs'
import { getFfmpegPath, getFfprobePath } from './binaries'
import type { FfmpegVersionResult } from '@shared/ipc'

/**
 * Read the version token from an ffmpeg/ffprobe binary. Both print a first line
 * of the form "<tool> version <VERSION> Copyright ..." (e.g.
 * "ffmpeg version 6.1.1-full_build-www.gyan.dev Copyright ..."), so we return the
 * token after "version". Resolves null if the binary is absent, errors, times
 * out, or the line doesn't parse — Settings then shows "not found" instead of
 * failing. Unlike yt-dlp these are never self-updated, so there's no update path.
 */
function readToolVersion(path: string): Promise<string | null> {
  if (!existsSync(path)) return Promise.resolve(null)
  return new Promise((resolve) => {
    execFile(path, ['-version'], { windowsHide: true, timeout: 15_000 }, (err, stdout) => {
      if (err) {
        resolve(null)
        return
      }
      const firstLine = stdout.split('\n', 1)[0] ?? ''
      const m = firstLine.match(/version\s+(\S+)/i)
      resolve(m?.[1] ?? null)
    })
  })
}

/** Versions of the bundled ffmpeg + ffprobe, read in parallel for the Settings panel. */
export async function getFfmpegVersions(): Promise<FfmpegVersionResult> {
  const [ffmpeg, ffprobe] = await Promise.all([
    readToolVersion(getFfmpegPath()),
    readToolVersion(getFfprobePath())
  ])
  return { ffmpeg, ffprobe }
}