Spotify playlist import

lib/api/deezer.dart

@@ -66,6 +66,15 @@ class DeezerAPI {
     return response.data;
   }
 
+  Future<Map> callPublicApi(String path) async {
+    Dio dio = Dio();
+    Response response = await dio.get(
+      'https://api.deezer.com/' + path,
+      options: Options(responseType: ResponseType.json, sendTimeout: 5000, receiveTimeout: 5000)
+    );
+    return response.data;
+  }
+
   //Authorize, bool = success
   Future<bool> authorize() async {
     try {
@@ -341,7 +350,7 @@ class DeezerAPI {
 
   //Create playlist
   //Status 1 - private, 2 - collaborative
-  Future createPlaylist(String title, {String description = "", int status = 1, List<String> trackIds = const []}) async {
+  Future<String> createPlaylist(String title, {String description = "", int status = 1, List<String> trackIds = const []}) async {
     Map data = await callApi('playlist.create', params: {
       'title': title,
       'description': description,
@@ -349,7 +358,7 @@ class DeezerAPI {
       'status': status
     });
     //Return playlistId
-    return data['results'];
+    return data['results'].toString();
   }
   
 }

lib/api/spotify.dart

@@ -0,0 +1,127 @@
+import 'package:dio/dio.dart';
+import 'package:freezer/api/deezer.dart';
+import 'package:freezer/api/download.dart';
+import 'package:freezer/api/definitions.dart';
+import 'package:html/parser.dart';
+import 'package:html/dom.dart';
+
+import 'dart:convert';
+import 'dart:async';
+
+
+SpotifyAPI spotify = SpotifyAPI();
+
+class SpotifyAPI {
+
+  SpotifyPlaylist importingSpotifyPlaylist;
+  StreamController importingStream = StreamController.broadcast();
+  bool doneImporting;
+
+  //Parse spotify URL to URI (spotify:track:1234)
+  String parseUrl(String url) {
+    Uri uri = Uri.parse(url);
+    if (uri.pathSegments.length > 3) return null; //Invalid URL
+    if (uri.pathSegments.length == 3) return 'spotify:${uri.pathSegments[1]}:${uri.pathSegments[2]}';
+    if (uri.pathSegments.length == 2) return 'spotify:${uri.pathSegments[0]}:${uri.pathSegments[1]}';
+    return null;
+  }
+
+  //Get spotify embed url from uri
+  String getEmbedUrl(String uri) => 'https://embed.spotify.com/?uri=$uri';
+
+  //Extract JSON data form spotify embed page
+  Future<Map> getEmbedData(String url) async {
+    //Fetch
+    Dio dio = Dio();
+    Response response = await dio.get(url);
+    //Parse
+    Document document = parse(response.data);
+    Element element = document.getElementById('resource');
+    return jsonDecode(element.innerHtml);
+  }
+
+  Future<SpotifyPlaylist> playlist(String uri) async {
+    //Load data
+    String url = getEmbedUrl(uri);
+    Map data = await getEmbedData(url);
+    //Parse
+    SpotifyPlaylist playlist = SpotifyPlaylist.fromJson(data);
+    return playlist;
+  }
+  
+  Future convertPlaylist(SpotifyPlaylist playlist, {bool downloadOnly = false}) async {
+    doneImporting = false;
+    importingSpotifyPlaylist = playlist;
+
+    //Create Deezer playlist
+    String playlistId;
+    if (!downloadOnly)
+      playlistId = await deezerAPI.createPlaylist(playlist.name, description: playlist.description);
+
+    //Search for tracks
+    for (SpotifyTrack track in playlist.tracks) {
+      Map deezer;
+      try {
+        //Search
+        deezer = await deezerAPI.callPublicApi('track/isrc:' + track.isrc);
+        if (deezer.containsKey('error')) throw Exception();
+        String id = deezer['id'].toString();
+        //Add
+        if (!downloadOnly)
+          await deezerAPI.addToPlaylist(id, playlistId);
+        if (downloadOnly)
+          await downloadManager.addOfflineTrack(Track(id: id), private: false);
+        track.state = TrackImportState.OK;
+      } catch (e) {
+        //On error
+        track.state = TrackImportState.ERROR;
+      }
+      //Add playlist id to stream, stream is for updating ui only
+      importingStream.add(playlistId);
+      importingSpotifyPlaylist = playlist;
+    }
+    doneImporting = true;
+    //Return DEEZER playlist id
+    return playlistId;
+  }
+
+}
+
+class SpotifyTrack {
+  String title;
+  String artists;
+  String isrc;
+  TrackImportState state = TrackImportState.NONE;
+
+  SpotifyTrack({this.title, this.artists, this.isrc});
+
+  //JSON
+  factory SpotifyTrack.fromJson(Map json) => SpotifyTrack(
+    title: json['name'],
+    artists: json['artists'].map((j) => j['name']).toList().join(', '),
+    isrc: json['external_ids']['isrc']
+  );
+}
+
+class SpotifyPlaylist {
+  String name;
+  String description;
+  List<SpotifyTrack> tracks;
+  String image;
+
+  SpotifyPlaylist({this.name, this.description, this.tracks, this.image});
+
+  //JSON
+  factory SpotifyPlaylist.fromJson(Map json) => SpotifyPlaylist(
+    name: json['name'],
+    description: json['description'],
+    image: json['images'][0]['url'],
+    tracks: json['tracks']['items'].map<SpotifyTrack>((j) => SpotifyTrack.fromJson(j['track'])).toList()
+  );
+}
+
+enum TrackImportState {
+  NONE,
+  ERROR,
+  OK
+}