src/sources/deezer.js

import crypto from 'node:crypto'
import { Buffer } from 'node:buffer'
import { PassThrough } from 'node:stream'

import config from '../../config.js'
import { debugLog, makeRequest, encodeTrack } from '../utils.js'

let sourceInfo = {
  licenseToken: null,
  csrfToken: null,
  mediaUrl: null,
  Cookie: null,
  jwtToken: null
}

const bufferSize = 2048
const IV = Buffer.from(Array.from({ length: 8 }, (_i, x) => x))

async function init() {
  if (sourceInfo.licenseToken) return;
  // TODO: Need to reset when timestamp is expired

  debugLog('deezer', 5, { type: 1, message: 'Fetching user data...' })

  const res = await makeRequest(`https://www.deezer.com/ajax/gw-light.php?method=deezer.getUserData&input=3&api_version=1.0&api_token=${config.search.sources.deezer.apiToken}`, {
    method: 'GET',
    getCookies: true
  })

  sourceInfo.Cookie = res.headers['set-cookie'].join('; ')
  
  if (config.search.sources.deezer.arl !== 'DISABLED') {
    sourceInfo.Cookie += `; arl=${config.search.sources.deezer.arl}`

    const { body: jwtInfo } = await makeRequest('https://auth.deezer.com/login/arl?jo=p&rto=c&i=c', {
      headers: {
        Cookie: sourceInfo.Cookie
      },
      method: 'POST'
    })

    sourceInfo.jwtToken = JSON.parse(jwtInfo).jwt
  } 

  sourceInfo.licenseToken = res.body.results.USER.OPTIONS.license_token
  sourceInfo.csrfToken = res.body.results.checkForm
  sourceInfo.mediaUrl = res.body.results.URL_MEDIA

  debugLog('deezer', 5, { type: 1, message: 'Successfully fetched user data.' })
}

async function loadFrom(query, type) {
  let endpoint

  switch (type[1]) {
    case 'track':
      endpoint = `track/${type[2]}`
      break
    case 'playlist':
      endpoint = `playlist/${type[2]}`
      break
    case 'album':
      endpoint = `album/${type[2]}`
      break
    default: {
      return {
        loadType: 'empty',
        data: {}
      }
    }
  }

  debugLog('loadtracks', 4, { type: 1, loadType: type[1], sourceName: 'Deezer', query })

  const { body: data } = await makeRequest(`https://api.deezer.com/2.0/${endpoint}`, { method: 'GET' })

  if (data.error) {
    if (data.error.code === 800) {
      return {
        loadType: 'empty',
        data: {}
      }
    }

    return {
      loadType: 'error',
      data: {
        message: data.error.message,
        severity: 'fault',
        cause: 'Unknown'
      }
    }
  }

  switch (type[1]) {
    case 'track': {
      const track = {
        identifier: data.id.toString(),
        isSeekable: true,
        author: data.artist.name,
        length: data.duration * 1000,
        isStream: false,
        position: 0,
        title: data.title,
        uri: data.link,
        artworkUrl: data.album.cover_xl,
        isrc: data.isrc,
        sourceName: 'deezer'
      }

      debugLog('loadtracks', 4, { type: 2, loadType: 'track', sourceName: 'Deezer', track, query })

      return {
        loadType: 'track',
        data: {
          encoded: encodeTrack(track),
          info: track,
          pluginInfo: {}
        }
      }
    }
    case 'album':
    case 'playlist': {
      const tracks = []

      if (data.tracks.data.length > config.options.maxAlbumPlaylistLength)
        data.tracks.data = data.tracks.data.slice(0, config.options.maxAlbumPlaylistLength)

      data.tracks.data.forEach(async (item, i) => {
        const track = {
          identifier: item.id.toString(),
          isSeekable: true,
          author: item.artist.name,
          length: item.duration * 1000,
          isStream: false,
          position: 0,
          title: item.title,
          uri: item.link,
          artworkUrl: type[1] === 'album' ? data.cover_xl : data.picture_xl,
          isrc: null,
          sourceName: 'deezer'
        }

        tracks.push({
          encoded: encodeTrack(track),
          info: track,
          pluginInfo: {}
        })
      })

      debugLog('loadtracks', 4, { type: 2, loadType: type[1], sourceName: 'Deezer', playlistName: data.title })

      return {
        loadType: type[1],
        data: {
          info: {
            name: data.title,
            selectedTrack: 0
          },
          pluginInfo: {},
          tracks
        }
      }
    }
  }
}

async function search(query, shouldLog) {
  if (shouldLog) debugLog('search', 4, { type: 1, sourceName: 'Deezer', query })

  const { body: data } = await makeRequest(`https://api.deezer.com/2.0/search?q=${encodeURI(query)}`, { method: 'GET' })

  // This API doesn't give ISRC, must change to internal API

  if (data.error) {
    return {
      loadType: 'error',
      data: {
        message: data.error.message,
        severity: 'fault',
        cause: 'Unknown'
      }
    }
  }

  if (data.total === 0) {
    if (shouldLog) debugLog('search', 4, { type: 3, sourceName: 'Deezer', query, message: 'No matches found.' })

    return {
      loadType: 'empty',
      data: {}
    }
  }

  const tracks = []

  if (data.data.length > config.options.maxResultsLength)
    data.data = data.data.filter((item, i) => i < config.options.maxResultsLength || item.type === 'track')

  data.data.forEach(async (item) => {
    const track = {
      identifier: item.id.toString(),
      isSeekable: true,
      author: item.artist.name,
      length: item.duration * 1000,
      isStream: false,
      position: 0,
      title: item.title,
      uri: item.link,
      artworkUrl: item.album.cover_xl,
      isrc: item.isrc,
      sourceName: 'deezer'
    }

    tracks.push({
      encoded: encodeTrack(track),
      info: track,
      pluginInfo: {}
    })
  })

  if (shouldLog)
    debugLog('search', 4, { type: 2, sourceName: 'Deezer', tracksLen: tracks.length, query })

  return {
    loadType: 'search',
    data: tracks
  }
}

async function retrieveStream(identifier, title) {
  const { body: data } = await makeRequest(`https://www.deezer.com/ajax/gw-light.php?method=song.getListData&input=3&api_version=1.0&api_token=${sourceInfo.csrfToken}`, {
    body: {
      sng_ids: [ identifier ]
    },
    headers: {
      Cookie: sourceInfo.Cookie
    },
    method: 'POST',
    disableBodyCompression: true
  })

  if (data.error.length !== 0) {
    const errorMessage = Object.keys(data.error).map((err) => data.error[err]).join('; ')

    debugLog('retrieveStream', 4, { type: 2, sourceName: 'Deezer', query: title, message: errorMessage })

    return {
      exception: {
        message: errorMessage,
        severity: 'fault',
        cause: 'Unknown'
      }
    }
  }

  const trackInfo = data.results.data[0]

  const { body: streamData } = await makeRequest('https://media.deezer.com/v1/get_url', {
    body: {
      license_token: sourceInfo.licenseToken,
      media: [{
        type: 'FULL',
        formats: [{
          cipher: 'BF_CBC_STRIPE',
          format: 'FLAC'
        }, {
          cipher: 'BF_CBC_STRIPE',
          format: 'MP3_256'
        }, {
          cipher: 'BF_CBC_STRIPE',
          format: 'MP3_128'
        }, {
          cipher: 'BF_CBC_STRIPE',
          format: 'MP3_MISC'
        }]
      }],
      track_tokens: [ trackInfo.TRACK_TOKEN ]
    },
    method: 'POST',
    disableBodyCompression: true
  })

  return {
    url: streamData.data[0].media[0].sources[0].url,
    protocol: 'https',
    format: 'arbitrary',
    additionalData: trackInfo
  }
}

async function loadLyrics(decodedTrack, _language) {
  const { body: video } = await makeRequest('https://pipe.deezer.com/api', {
    headers: {
      Cookie: sourceInfo.Cookie,
      Authorization: `Bearer ${sourceInfo.jwtToken}`
    },
    body: {
      operationName: 'SynchronizedTrackLyrics',
      query: 'query SynchronizedTrackLyrics($trackId: String!) {\n  track(trackId: $trackId) {\n    ...SynchronizedTrackLyrics\n    __typename\n  }\n}\n\nfragment SynchronizedTrackLyrics on Track {\n  id\n  lyrics {\n    ...Lyrics\n    __typename\n  }\n  album {\n    cover {\n      small: urls(pictureRequest: {width: 100, height: 100})\n      medium: urls(pictureRequest: {width: 264, height: 264})\n      large: urls(pictureRequest: {width: 800, height: 800})\n      explicitStatus\n      __typename\n    }\n    __typename\n  }\n  __typename\n}\n\nfragment Lyrics on Lyrics {\n  id\n  copyright\n  text\n  writers\n  synchronizedLines {\n    ...LyricsSynchronizedLines\n    __typename\n  }\n  __typename\n}\n\nfragment LyricsSynchronizedLines on LyricsSynchronizedLine {\n  lrcTimestamp\n  line\n  lineTranslated\n  milliseconds\n  duration\n  __typename\n}',
      variables: {
        trackId: decodedTrack.identifier
      }
    },
    method: 'POST',
    disableBodyCompression: true
  })

  if (video.errors) {
    const errorMessage = video.errors.map((err) => `${err.message} (${err.type})`).join('; ')

    debugLog('loadlyrics', 4, { type: 3, track: decodedTrack, sourceName: 'Deezer', message: errorMessage })
        
    return {
      loadType: 'error',
      data: {
        message: errorMessage,
        severity: 'common',
        cause: 'Unknown'
      }
    }
  }

  const lyricsEvents = video.data.track.lyrics.synchronizedLines.map((event) => {
    return {
      startTime: event.milliseconds,
      endTime: event.milliseconds + event.duration,
      text: event.line
    }
  })

  return {
    loadType: 'lyricsSingle',
    data: {
      name: 'original',
      synced: true,
      data: lyricsEvents,
      rtl: false
    }
  }
}

function _calculateKey(songId) {
  const key = config.search.sources.deezer.decryptionKey
  const songIdHash = crypto.createHash('md5').update(songId, 'ascii').digest('hex')
  const trackKey = Buffer.alloc(16)

  for (let i = 0; i < 16; i++) {
    trackKey.writeInt8(songIdHash[i].charCodeAt(0) ^ songIdHash[i + 16].charCodeAt(0) ^ key[i].charCodeAt(0), i)
  }

  return trackKey
}

function loadTrack(title, url, trackInfos) {
  return new Promise(async (resolve) => {
    const stream = new PassThrough()

    const trackKey = _calculateKey(trackInfos.SNG_ID)
    let buf = Buffer.alloc(0)
    let i = 0

    const res = await makeRequest(url, {
      method: 'GET',
      streamOnly: true
    })

    res.stream.on('end', () => stream.end())
    res.stream.on('error', (error) => {
      debugLog('retrieveStream', 4, { type: 2, sourceName: 'Deezer', query: title, message: error.message })

      resolve({
        status: 1,
        exception: {
          message: error.message,
          severity: 'fault',
          cause: 'Unknown'
        }
      })
    })

    res.stream.on('readable', () => {
      let chunk = null
      while (1) {
        chunk = res.stream.read(bufferSize)

        if (!chunk) {
          if (res.stream.readableLength) {
            chunk = res.stream.read(res.stream.readableLength)
            buf = Buffer.concat([ buf, chunk ])
          }

          break
        } else {
          buf = Buffer.concat([ buf, chunk ])
        }

        while (buf.length >= bufferSize) {
          const bufferSized = buf.subarray(0, bufferSize)

          if (i % 3 === 0) {
            const decipher = crypto.createDecipheriv('bf-cbc', trackKey, IV).setAutoPadding(false)
    
            stream.push(decipher.update(bufferSized))
            stream.push(decipher.final())
          } else {
            stream.push(bufferSized)
          }

          i++
      
          buf = buf.subarray(bufferSize)
        }
      }

      resolve(stream)
    })
  })
}

export default {
  init,
  loadFrom,
  search,
  retrieveStream,
  loadLyrics,
  loadTrack
}