Improve youtube connector

Parse description to get track info.
Remove YouTube Topic support.

Resolves #1896.

src/connectors/youtube.js

@@ -22,17 +22,6 @@ const CATEGORIES = [
 	CATEGORY_SCIENCE_AND_TECHNOLOGY
 ];
 
-// Basic support for languages the extension is traslated to.
-// TODO: Remove if description parsing is implemented.
-const TOPIC_SUFFIXES = [
-	/(.+) - Topic/, // EN
-	/(.+) – Thema/, // DE
-	/(.+) – тема/, // RU
-	/(.+) - Tema/, // ES
-	/(.+) – temat/, // PL
-	/(.+) – Tópico/, // PT
-];
-
 /**
  * Array of categories allowed to be scrobbled.
  * @type {Array}
@@ -54,11 +43,19 @@ const videoSelector = '.html5-main-video';
 const videoTitleSelector = '.html5-video-player .ytp-title-link';
 const channelNameSelector = '#top-row .ytd-channel-name a';
 
+let currentVideoDescription = null;
+let artistTrackFromDescription = null;
+
 readConnectorOptions();
 
 Connector.playerSelector = '#content';
 
-Connector.getArtistTrack = () => {
+Connector.getTrackInfo = () => {
+	const trackInfo = getTrackInfoFromDescription();
+	if (!Util.isArtistTrackEmpty(trackInfo)) {
+		return trackInfo;
+	}
+
 	let { artist, track } = Util.processYoutubeVideoTitle(
 		Util.getTextFromSelectors(videoTitleSelector)
 	);
@@ -127,11 +124,7 @@ Connector.isScrobblingAllowed = () => {
 	return true;
 };
 
-Connector.applyFilter(
-	MetadataFilter.getYoutubeFilter().append({
-		artist: removeTopicSuffix,
-	})
-);
+Connector.applyFilter(MetadataFilter.getYoutubeFilter());
 
 /**
  * Get video category.
@@ -164,17 +157,6 @@ function getVideoCategory(videoId) {
 	return categoryCache.get(videoId);
 }
 
-function removeTopicSuffix(text) {
-	for (const regex of TOPIC_SUFFIXES) {
-		const topicMatch = text.match(regex);
-		if (topicMatch) {
-			return topicMatch[1];
-		}
-	}
-
-	return text;
-}
-
 async function fetchCategoryId() {
 	await fillMoreSection();
 
@@ -246,3 +228,19 @@ async function readConnectorOptions() {
 		allowedCategories.push(CATEGORY_ENTERTAINMENT);
 	}
 }
+
+function getVideoDescription() {
+	return $('#description').text();
+}
+
+function getTrackInfoFromDescription() {
+	const description = getVideoDescription();
+	if (currentVideoDescription === description) {
+		return artistTrackFromDescription;
+	}
+
+	currentVideoDescription = description;
+	artistTrackFromDescription = Util.parseYtVideoDescription(description);
+
+	return artistTrackFromDescription;
+}

src/core/content/util.js

@@ -505,6 +505,54 @@ const Util = {
 	 * @type {String}
 	 */
 	ARTIST_SEPARATOR: ', ',
+
+	descFirstLine: 'Provided to YouTube',
+
+	descLastLine: 'Auto-generated by YouTube.',
+
+	descArtistTrackSeparator: ' · ',
+
+	isYtVideoDescriptionValid(desc) {
+		return desc && (
+			desc.startsWith(this.descFirstLine) ||
+			desc.endsWith(this.descLastLine)
+		);
+	},
+
+	parseYtVideoDescription(desc) {
+		if (!this.isYtVideoDescriptionValid(desc)) {
+			return null;
+		}
+
+		const lines = desc.split('\n').filter((line) => {
+			return line.length > 0;
+		}).filter((line) => {
+			return !line.startsWith(this.descFirstLine);
+		});
+
+		const firstLine = lines[0];
+		const secondLine = lines[1];
+
+		const trackInfo = firstLine.split(this.descArtistTrackSeparator);
+		const numberOfFields = trackInfo.length;
+
+		const album = secondLine;
+		let artist = null;
+		let track = null;
+		let featArtists = null;
+
+		if (numberOfFields === 2) {
+			[track, artist] = trackInfo;
+		} else if (numberOfFields > 2) {
+			[track, artist, featArtists] = trackInfo;
+
+			const featArtistsStr = featArtists.split(this.ytDescSeparator)
+				.join(this.ARTIST_SEPARATOR);
+			track = `${track} (feat. ${featArtistsStr})`;
+		}
+
+		return { artist, track, album };
+	},
 };
 
 /**

tests/content/util.js

@@ -295,6 +295,80 @@ const IS_ARTIST_TRACK_EMPTY_DATA = [{
 	expected: false
 }];
 
+const YT_DESCRIPTION_EXAMPLE_1 = `Provided to YouTube by IDOL
+
+Tranquility (Forces of Nature Remix) · Aquasky
+
+Shadow Era, Pt. 2
+
+℗ Passenger Ltd
+
+Released on: 2015-10-09
+
+Lyricist: B. Newitt
+Lyricist: D. Wallace
+Lyricist: K. Bailey
+Composer: B. Newitt
+Composer: D. Wallace
+Composer: K. Bailey
+
+Auto-generated by YouTube.`;
+
+const YT_DESCRIPTION_EXAMPLE_2 = `Capoeira (Airbase pres. Scarab Remix) · Under Sun
+
+Capoeira
+
+℗ Armada Music B.V.
+
+Released on: 2006-08-21
+
+A R T I S T: Under Sun
+
+Auto-generated by YouTube.`;
+
+const YT_DESCRIPTION_EXAMPLE_3 = `Provided to YouTube by The Orchard Enterprises
+
+Fugitive · Time, The Valuator · Mattéo Gelsomino
+
+How Fleeting, How Fragile
+
+℗ 2018 Long Branch Records
+
+Released on: 2018-08-03
+
+Auto-generated by YouTube.`;
+
+const PARSE_YT_VIDEO_DESCRIPTION_DATA = [{
+	description: 'should not parse null description',
+	source: null,
+	expected: null
+}, {
+	description: 'should parse normal description',
+	source: YT_DESCRIPTION_EXAMPLE_1,
+	expected: {
+		album: 'Shadow Era, Pt. 2',
+		track: 'Tranquility (Forces of Nature Remix)',
+		artist: 'Aquasky',
+	}
+}, {
+	description: 'should parse description w/o "Autogenerated" header',
+	source: YT_DESCRIPTION_EXAMPLE_2,
+	expected: {
+		album: 'Capoeira',
+		track: 'Capoeira (Airbase pres. Scarab Remix)',
+		artist: 'Under Sun',
+	}
+}, {
+	description: 'should parse description w/ featuring artists',
+	source: YT_DESCRIPTION_EXAMPLE_3,
+	expected: {
+		album: 'How Fleeting, How Fragile',
+		track: 'Fugitive (feat. Mattéo Gelsomino)',
+		artist: 'Time, The Valuator',
+	}
+}];
+
+
 /**
  * Test 'Util.splitArtistTrack' function.
  */
@@ -401,20 +475,36 @@ function testIsArtistTrackEmpty() {
 	testFunction(Util.isArtistTrackEmpty, IS_ARTIST_TRACK_EMPTY_DATA);
 }
 
+/**
+ * Test 'Util.parseYtVideoDescription' function.
+ */
+function testParseYtVideoDescription() {
+	testFunction(
+		Util.parseYtVideoDescription,
+		PARSE_YT_VIDEO_DESCRIPTION_DATA,
+		{ isDeepEqual: true }
+	);
+}
+
 /**
  * Test function.
  * @param  {Function} func Function to be tested
  * @param  {Array} testData Array of test data
+ * @param  {Boolean} isDeepEqual Should use deep equal
  */
-function testFunction(func, testData) {
+function testFunction(func, testData, { isDeepEqual = false } = {}) {
 	const boundFunc = func.bind(Util);
 
 	for (let data of testData) {
 		let { description, source, expected } = data;
 		let actual = boundFunc(source);
 
 		it(description, function() {
-			expect(actual).to.be.equal(expected);
+			if (isDeepEqual) {
+				expect(actual).to.be.deep.equal(expected);
+			} else {
+				expect(actual).to.be.equal(expected);
+			}
 		});
 	}
 }
@@ -429,6 +519,7 @@ function runTests() {
 	describe('splitArtistTrack', testSplitArtistTrack);
 	describe('isArtistTrackEmpty', testIsArtistTrackEmpty);
 	describe('escapeBadTimeValues', testEscapeBadTimeValues);
+	describe('parseYtVideoDescription', testParseYtVideoDescription);
 	describe('extractUrlFromCssProperty', testExtractTrackArtFromCss);
 	describe('processYoutubeVideoTitle', testProcessYoutubeVideoTitle);
 	describe('getYoutubeVideoIdFromUrl', testGetYoutubeVideoIdFromUrl);