video-downloader/src/lib/__tests__/ytdlp.test.ts

import { buildYtdlpArgs } from '../ytdlp'

const base = {
  url: 'https://www.youtube.com/watch?v=dQw4w9WgXcQ',
  uuid: 'abc-123',
  format: 'mp4',
  quality: 'best',
  subtitles: false,
  subtitleLangs: null,
  clipStart: null,
  clipEnd: null,
  audioQuality: null,
  extraArgs: null,
}

describe('buildYtdlpArgs', () => {
  it('always includes --no-playlist', () => {
    expect(buildYtdlpArgs(base)).toContain('--no-playlist')
  })

  it('sets output path with uuid and %(ext)s template', () => {
    const args = buildYtdlpArgs(base)
    const idx = args.indexOf('-o')
    expect(idx).toBeGreaterThan(-1)
    expect(args[idx + 1]).toContain('abc-123')
    expect(args[idx + 1]).toContain('%(ext)s')
  })

  it('always sets --merge-output-format to the chosen video format', () => {
    const args = buildYtdlpArgs(base)
    const idx = args.indexOf('--merge-output-format')
    expect(idx).toBeGreaterThan(-1)
    expect(args[idx + 1]).toBe('mp4')
  })

  it('adds a height filter to -f when quality is not "best"', () => {
    const args = buildYtdlpArgs({ ...base, quality: '1080p' })
    const idx = args.indexOf('-f')
    expect(idx).toBeGreaterThan(-1)
    expect(args[idx + 1]).toContain('height<=?1080')
  })

  it('does not add a height filter when quality is "best"', () => {
    const args = buildYtdlpArgs(base)
    const idx = args.indexOf('-f')
    expect(args[idx + 1]).not.toContain('height<=?')
  })

  it('extracts audio with -x and --audio-format when format is mp3', () => {
    const args = buildYtdlpArgs({ ...base, format: 'mp3' })
    expect(args).toContain('-x')
    const idx = args.indexOf('--audio-format')
    expect(args[idx + 1]).toBe('mp3')
    expect(args).not.toContain('--merge-output-format')
  })

  it('sets --audio-quality to 0 for best mp3 quality', () => {
    const args = buildYtdlpArgs({ ...base, format: 'mp3', audioQuality: 'best' })
    const idx = args.indexOf('--audio-quality')
    expect(args[idx + 1]).toBe('0')
  })

  it('sets --audio-quality to a bitrate when a specific mp3 quality is given', () => {
    const args = buildYtdlpArgs({ ...base, format: 'mp3', audioQuality: '192' })
    const idx = args.indexOf('--audio-quality')
    expect(args[idx + 1]).toBe('192K')
  })

  it('adds subtitle flags when subtitles is true', () => {
    const args = buildYtdlpArgs({ ...base, subtitles: true })
    expect(args).toContain('--write-subs')
    expect(args).toContain('--write-auto-subs')
    expect(args).toContain('--sub-lang')
  })

  it('does not add subtitle flags when subtitles is false', () => {
    expect(buildYtdlpArgs(base)).not.toContain('--write-subs')
  })

  it('defaults subtitle languages to fr,en when none are given', () => {
    const args = buildYtdlpArgs({ ...base, subtitles: true })
    const idx = args.indexOf('--sub-lang')
    expect(args[idx + 1]).toBe('fr,en')
  })

  it('uses the given subtitle languages when provided', () => {
    const args = buildYtdlpArgs({ ...base, subtitles: true, subtitleLangs: ['es', 'it'] })
    const idx = args.indexOf('--sub-lang')
    expect(args[idx + 1]).toBe('es,it')
  })

  it('adds --download-sections when a clip range is given', () => {
    const args = buildYtdlpArgs({ ...base, clipStart: 10, clipEnd: 30 })
    const idx = args.indexOf('--download-sections')
    expect(args[idx + 1]).toBe('*10-30')
  })

  it('defaults clip start to 0 when only clipEnd is given', () => {
    const args = buildYtdlpArgs({ ...base, clipEnd: 30 })
    const idx = args.indexOf('--download-sections')
    expect(args[idx + 1]).toBe('*0-30')
  })

  it('leaves the clip end open when only clipStart is given', () => {
    const args = buildYtdlpArgs({ ...base, clipStart: 10 })
    const idx = args.indexOf('--download-sections')
    expect(args[idx + 1]).toBe('*10-')
  })

  it('does not add --download-sections when no clip range is given', () => {
    expect(buildYtdlpArgs(base)).not.toContain('--download-sections')
  })

  it('appends extra args from a JSON array string', () => {
    const args = buildYtdlpArgs({
      ...base,
      extraArgs: '["--sponsorblock-remove","all"]',
    })
    expect(args).toContain('--sponsorblock-remove')
    expect(args).toContain('all')
  })

  it('ignores malformed extraArgs JSON', () => {
    expect(() =>
      buildYtdlpArgs({ ...base, extraArgs: 'not-json' })
    ).not.toThrow()
  })

  it('url is the last argument', () => {
    const args = buildYtdlpArgs(base)
    expect(args[args.length - 1]).toBe(base.url)
  })
})