mucke/lib/system/datasources/music_data_source_contract.dart

import '../models/album_model.dart';
import '../models/song_model.dart';

abstract class MusicDataSource {
  Future<List<AlbumModel>> getAlbums();
  Future<bool> albumExists(AlbumModel albumModel);
  Future<void> insertAlbum(AlbumModel albumModel);

  Future<List<SongModel>> getSongs();
  Future<List<SongModel>> getSongsFromAlbum(AlbumModel album);
  Future<bool> songExists(SongModel songModel);
  Future<void> insertSong(SongModel songModel);
}