Implementation of Youtube Search API with Pure Javascript

YoutubeSearcher.js

var YoutubeSearcher = (function() {

	function YoutubeSearcher() {
		this.configuration = {};
		this.dependencies = {};
	}

	YoutubeSearcher.prototype.searchSongs = function(query) {

		var dependencies = this.dependencies;
		var q = dependencies.q;
		var rootScope = dependencies.rootScope;
		var httpService = dependencies.httpService;

		var defered = q.defer();
		var promise = defered.promise;

		//-----------------First request-----------------

		var apiKey = this.configuration.api_key;
		var urlRequest = 'https://www.googleapis.com/youtube/v3/search?videoEmbeddable=true&order=relevance&part=id&q=' + query + '&type=video&maxResults=50&key=' + apiKey;

		var errorCallback = function(data) {

			var message = 'GENERAL_ERROR';

			if (data.status === 0) {
				message = 'NETWORK_ERROR';
			}

			rootScope.$broadcast('showSongsSearchResults', new RequestResponse('Error', message, {}));
		};

		var successCallback = function(data) {

			var songsId = YoutubeSearcher.prototype.getResourcesIdFromYoutubeResponse(data.data.items, 'searches-songs');

			if (songsId === '') {

				rootScope.$broadcast('showSongsSearchResults', new RequestResponse('Error', 'SEARCH_SONGS_NOT_FOUND', {
					results_not_found: true
				}));

			} else {
				defered.resolve(songsId);
			}

		};

		httpService.get(urlRequest, {}, successCallback, errorCallback);



		//-----------------Second request-----------------

		var resolveCallback = function(songsId) {

			urlRequest = 'https://www.googleapis.com/youtube/v3/videos?part=snippet%2C+contentDetails%2C+statistics&id=' + songsId + '&key=' + apiKey;

			var successCallback = function(data) {

				var songsList = YoutubeSearcher.prototype.getSongsListFromYoutubeResponse(data.data.items, dependencies, true);
				songsList.toArray().sort(SongUtilities.sortByViews);

				var response = {
					songs: songsList,
					query: query
				};

				if (songsList.size() === 0) {
					response = new RequestResponse('Error', 'SEARCH_SONGS_NOT_FOUND', response);
				} else {
					response = new RequestResponse('Success', '', response);
				}

				rootScope.$broadcast('showSongsSearchResults', response);
			};

			httpService.get(urlRequest, {}, successCallback, errorCallback);
		};

		promise.then(resolveCallback);
	};

	YoutubeSearcher.prototype.getSuggestedSongs = function(songSourceId) {

		var dependencies = this.dependencies;
		var q = dependencies.q;
		var rootScope = dependencies.rootScope;
		var httpService = dependencies.httpService;

		var defered = q.defer();
		var promise = defered.promise;

		//-----------------First request-----------------

		var apiKey = this.configuration.api_key;
		var urlRequest = 'https://www.googleapis.com/youtube/v3/search?part=snippet&&maxResults=10&relatedToVideoId=' + songSourceId + '&type=video&key=' + apiKey;

		var errorCallback = function(data) {

			var message = 'GENERAL_ERROR';

			if (data.status === 0) {
				message = 'NETWORK_ERROR';
			}

			rootScope.$broadcast('updateSuggestedSongs', new RequestResponse('Error', message, {}));
		};

		var successCallback = function(data) {

			var songsId = YoutubeSearcher.prototype.getResourcesIdFromYoutubeResponse(data.data.items, 'suggested-songs');

			if (songsId === '') {
				rootScope.$broadcast('updateSuggestedSongs', new RequestResponse('Error', 'RELATED_SONGS_NOT_FOUND', {}));
			} else {
				defered.resolve(songsId);
			}

		};

		httpService.get(urlRequest, {}, successCallback, errorCallback);



		//-----------------Second request-----------------

		var resolveCallback = function(songsId) {

			urlRequest = 'https://www.googleapis.com/youtube/v3/videos?part=snippet%2C+contentDetails%2C+statistics&id=' + songsId + '&key=' + apiKey;

			var successCallback = function(data) {

				var songsList = YoutubeSearcher.prototype.getSongsListFromYoutubeResponse(data.data.items, dependencies, true);
				songsList.toArray().sort(SongUtilities.sortByViews);

				var response = {
					songs: songsList
				};

				if (songsList.size() === 0) {
					response = new RequestResponse('Error', 'RELATED_SONGS_NOT_FOUND', response);
				} else {
					response = new RequestResponse('Success', '', response);
				}

				rootScope.$broadcast('updateSuggestedSongs', response);
			};

			httpService.get(urlRequest, {}, successCallback, errorCallback);
		};

		promise.then(resolveCallback);
	};

	YoutubeSearcher.prototype.searchPlaylists = function(query) {

		var dependencies = this.dependencies;
		var q = dependencies.q;
		var rootScope = dependencies.rootScope;
		var httpService = dependencies.httpService;

		var defered = q.defer();
		var promise = defered.promise;

		//-----------------First request-----------------

		var apiKey = this.configuration.api_key;
		var urlRequest = 'https://www.googleapis.com/youtube/v3/search?part=snippet&q=' + query + '&type=playlist&fields=items%2Fid&maxResults=3&key=' + apiKey;

		var errorCallback = function(data) {

			var message = 'GENERAL_ERROR';

			if (data.status === 0) {
				message = 'NETWORK_ERROR';
			}

			rootScope.$broadcast('showPlaylistsSearchResults', new RequestResponse('Error', message, {}));
		};

		var successCallback = function(data) {

			var playlistsId = YoutubeSearcher.prototype.getResourcesIdFromYoutubeResponse(data.data.items, 'searches-playlists');

			if (playlistsId === '') {

				rootScope.$broadcast('showPlaylistsSearchResults', new RequestResponse('Error', 'SEARCH_PLAYLISTS_NOT_FOUND', {
					results_not_found: true
				}));

			} else {
				defered.resolve(playlistsId);
			}

		};

		httpService.get(urlRequest, {}, successCallback, errorCallback);



		//-----------------Second request-----------------

		var resolveCallback = function(playlistsId) {

			urlRequest = 'https://www.googleapis.com/youtube/v3/playlists?part=contentDetails%2C+snippet&fields=items(contentDetails%2Cid%2Csnippet)&id=' + playlistsId + '&key=' + apiKey;

			var successCallback = function(data) {

				var playlists = new List();
				var responseData = data.data.items;
				var numberResults = responseData.length;

				for (var i = 0; i < numberResults; i++) {

					var item = responseData[i];
					var playlist = new Playlist();

					playlist.index = i;
					playlist.source = 'Youtube';
					playlist.source_id = item.id;
					playlist.thumbnail = item.snippet.thumbnails && item.snippet.thumbnails.default ? item.snippet.thumbnails.default.url : 'https://i.ytimg.com/vi/6F4BU6OakHY/mqdefault.jpg';
					playlist.title = item.snippet.title;
					playlists.add(playlist);
				}

				var response = new RequestResponse('Success', '', {
					playlists: playlists
				});

				rootScope.$broadcast('showPlaylistsSearchResults', response);
			};

			httpService.get(urlRequest, {}, successCallback, errorCallback);
		};

		promise.then(resolveCallback);
	};

	YoutubeSearcher.prototype.getPlaylistSongs = function(playlist) {

		var dependencies = this.dependencies;
		var q = dependencies.q;
		var rootScope = dependencies.rootScope;
		var httpService = dependencies.httpService;

		var defered = q.defer();
		var promise = defered.promise;

		//-----------------First request-----------------

		var apiKey = this.configuration.api_key;
		var urlRequest = 'https://www.googleapis.com/youtube/v3/playlistItems?part=contentDetails&playlistId=' + playlist.source_id + '&maxResults=50&key=' + apiKey;

		var errorCallback = function(data) {

			var message = 'GENERAL_ERROR';

			if (data.status === 0) {
				message = 'NETWORK_ERROR';
			}

			rootScope.$broadcast('getPlaylistSongs', new RequestResponse('Error', message, {
				playlist: playlist
			}));
		};

		var successCallback = function(data) {

			var songsId = YoutubeSearcher.prototype.getResourcesIdFromYoutubeResponse(data.data.items, 'get-playlist-songs');

			if (songsId === '') {

				rootScope.$broadcast('getPlaylistSongs', new RequestResponse('Error', 'PLAYLIST_SONGS_NOT_FOUND', {
					playlist: playlist
				}));

			} else {
				defered.resolve(songsId);
			}

		};

		httpService.get(urlRequest, {}, successCallback, errorCallback);



		//-----------------Second request-----------------

		var resolveCallback = function(songsId) {

			urlRequest = 'https://www.googleapis.com/youtube/v3/videos?videoEmbeddable=true&part=snippet%2C+contentDetails&id=' + songsId + '&key=' + apiKey;

			var successCallback = function(data) {

				var songsList = YoutubeSearcher.prototype.getSongsListFromYoutubeResponse(data.data.items, dependencies);

				var response = {
					playlist: playlist,
					songs: songsList
				};

				if (songsList.size() === 0) {
					response = new RequestResponse('Error', 'PLAYLIST_SONGS_NOT_FOUND', response);
				} else {
					response = new RequestResponse('Success', '', response);
				}

				rootScope.$broadcast('getPlaylistSongs', response);
			};

			httpService.get(urlRequest, {}, successCallback, errorCallback);
		};

		promise.then(resolveCallback);
	};

	YoutubeSearcher.prototype.getResourcesIdFromYoutubeResponse = function(items, source) {

		var resourcesId = '';
		var numberSongs = items.length;

		if (numberSongs > 0) {

			var i;

			if (source === 'suggested-songs') {
				numberSongs = (numberSongs > 5 ? 5 : numberSongs);
			}

			if (source === 'searches-songs' || source === 'suggested-songs') {

				for (i = 0; i < numberSongs; i++) {
					resourcesId += items[i].id.videoId + ',';
				}

			} else if (source === 'searches-playlists') {

				for (i = 0; i < numberSongs; i++) {
					resourcesId += items[i].id.playlistId + ',';
				}

			} else if (source === 'get-playlist-songs') {

				for (i = 0; i < numberSongs; i++) {
					resourcesId += items[i].contentDetails.videoId + ',';
				}

			}

			resourcesId = resourcesId.substring(0, resourcesId.length - 1);
		}

		return resourcesId;
	};

	YoutubeSearcher.prototype.getSongsListFromYoutubeResponse = function(items, dependencies, getStatistics) {

		var maxDurationSongs = dependencies.maxDurationSongs;
		var blacklistConfig = {};

		var songsList = new List();
		var numberSongs = items.length;

		if (dependencies.rootScope.blacklistConfig) {
			blacklistConfig = dependencies.rootScope.blacklistConfig;
		}

		for (var i = 0; i < numberSongs; i++) {

			var item = items[i];
			var song = new Song();

			song.source = 'Youtube';
			song.source_id = item.id;
			song.thumbnail = item.snippet.thumbnails && item.snippet.thumbnails.medium ? item.snippet.thumbnails.medium.url : 'https://i.ytimg.com/vi/6F4BU6OakHY/mqdefault.jpg';
			song.title = item.snippet.title;

			var blackListValidation = blacklistConfig.is_enabled && blacklistConfig.words !== '' ? SongUtilities.areKeywordsContainedInTitle(song.title, blacklistConfig.words) : false;

			if (song.title.toLowerCase().indexOf('cover') !== -1 || song.title.toLowerCase().indexOf('tutorial') !== -1 || blackListValidation) {
				continue;
			}

			if (item.snippet.categoryId === '10') {

				var duration = item.contentDetails.duration;
				duration = SongUtilities.normalizeDuration(duration, maxDurationSongs);

				if (duration !== null) {

					song.duration = duration;

					if (getStatistics) {
						if (item.statistics && item.statistics.viewCount) {
							song.views = parseInt(item.statistics.viewCount);
						} else {
							song.views = numberSongs - i;
						}
					}

					songsList.add(song);
				}
			}
		}

		return songsList;
	};

	return YoutubeSearcher;

})();