freezer/lib/api/pipe_api.dart

import 'dart:convert';

import 'package:dio/dio.dart';
import 'package:freezer/api/deezer.dart';
import 'package:freezer/api/definitions.dart';
import 'package:logging/logging.dart';

final pipeAPI = PipeAPI._();

class PipeAPI {
  PipeAPI._();

  // JWT for pipe.deezer.com
  String? _jwt;
  int _jwtExpiration = 0;

  final _logger = Logger('PipeAPI');

  Dio get dio => deezerAPI.dio;

  Future<void> authorize({bool force = false}) async {
    // authorize on pipe.deezer.com

    if (!force &&
        DateTime.timestamp().millisecondsSinceEpoch ~/ 1000 < _jwtExpiration) {
      // only continue if JWT expired!
      return;
    }

    // arl should be contained in cookies, so we should be fine
    var res = await dio.post('https://auth.deezer.com/login/arl?jo=p&rto=c&i=c',
        options: Options(responseType: ResponseType.plain));
    final data = jsonDecode(res.data);

    if (res.statusCode == 400) {
      // renew token (refresh token should be in cookies)
      res = await dio.post('https://auth.deezer.com/login/renew?jo=p&rto=c&i=c',
          options: Options(responseType: ResponseType.plain));
    }

    if (res.statusCode != 200 || data['jwt'] == null || data['jwt'] == '') {
      throw Exception('Pipe authentication failed!');
    }

    _jwt = data['jwt'];
    _logger.fine('got jwt: $_jwt');
    // decode JWT
    final parts = _jwt!.split('.');
    final jwtData = jsonDecode(utf8.decode(base64Url.decode(parts[1])));
    _jwtExpiration = jwtData['exp'];
  }

  Future<Map<dynamic, dynamic>> callApi(
      String operationName, String query, Map<String, dynamic> variables,
      {CancelToken? cancelToken}) async {
    // authorize if necessary.
    await authorize();

    final res = await dio.post('https://pipe.deezer.com/api',
        data: jsonEncode({
          'operationName': operationName,
          'variables': variables,
          'query': query,
        }),
        options: Options(headers: {'Authorization': 'Bearer $_jwt'}),
        cancelToken: cancelToken);
    return res.data;
  }

  // -- Not working --
  Future<(String, int)> getTrackToken(String trackId) async {
    final data = await callApi(
      'TrackMediaToken',
      'query TrackMediaToken(\$trackId: String!) {\n track(trackId: \$trackId) {\n media {\n token {\n payload\n expiresAt\n __typename\n }\n __typename\n }\n __typename\n }\n}',
      {'trackId': trackId},
    );

    print('[getTrackToken] $data');

    return (
      data['data']['track']['media']['token']['payload'] as String,
      data['data']['track']['media']['token']['expiresAt'] as int
    );
  }

  Future<Lyrics?> lyrics(String trackId, {CancelToken? cancelToken}) async {
    final data = await callApi(
      'SynchronizedTrackLyrics',
      r'''query SynchronizedTrackLyrics($trackId: String!) {
  track(trackId: $trackId) {
    ...SynchronizedTrackLyrics
    __typename
  }
}

fragment SynchronizedTrackLyrics on Track {
  id
  lyrics {
    ...Lyrics
    __typename
  }
  __typename
}

fragment Lyrics on Lyrics {
  id
  copyright
  text
  writers
  synchronizedLines {
    ...LyricsSynchronizedLines
    __typename
  }
  __typename
}

fragment LyricsSynchronizedLines on LyricsSynchronizedLine {
  lrcTimestamp
  line
  lineTranslated
  milliseconds
  duration
  __typename
}''',
      {'trackId': trackId},
      cancelToken: cancelToken,
    );
    if (data['errors'] != null && data['errors'].isNotEmpty) {
      for (final Map error in data['errors']) {
        if (error['type'] == 'JwtTokenExpiredError') {
          await authorize(force: true);
          return lyrics(trackId, cancelToken: cancelToken);
        }
      }

      throw Exception(data['errors']);
    }

    final lrc = data['data']['track']['lyrics'] as Map?;
    if (lrc == null) {
      return null;
    }

    if (lrc['synchronizedLines'] != null) {
      return Lyrics(
          id: lrc['id'],
          writers: lrc['writers'],
          sync: true,
          lyrics: (lrc['synchronizedLines'] as List)
              .map<Lyric>((lrc) => Lyric.fromPrivateJson(lrc as Map))
              .toList(growable: false));
    }

    return Lyrics(
        id: lrc['id'],
        writers: lrc['writers'],
        sync: false,
        lyrics: [Lyric(text: lrc['text'])]);
  }
}