/* * Copyright (C) 2019-2020 Yomichan Authors * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <https://www.gnu.org/licenses/>. */ /* global * CacheMap * TextToSpeechAudio */ class AudioSystem { constructor({getAudioInfo, cacheSize=32}) { this._cache = new CacheMap(cacheSize); this._getAudioInfo = getAudioInfo; } prepare() { // speechSynthesis.getVoices() will not be populated unless some API call is made. if (typeof speechSynthesis === 'undefined') { return; } const eventListeners = new EventListenerCollection(); const onVoicesChanged = () => { eventListeners.removeAllEventListeners(); }; eventListeners.addEventListener(speechSynthesis, 'voiceschanged', onVoicesChanged, false); } async createDefinitionAudio(sources, expression, reading, details) { const key = [expression, reading]; const cacheValue = this._cache.get(key); if (typeof cacheValue !== 'undefined') { const {audio, source} = cacheValue; const index = sources.indexOf(source); if (index >= 0) { return {audio, index}; } } for (let i = 0, ii = sources.length; i < ii; ++i) { const source = sources[i]; const info = await this._getAudioInfo(source, expression, reading, details); if (info === null) { continue; } let audio; try { switch (info.type) { case 'url': { const {details: {url}} = info; audio = await this.createAudio(url); } break; case 'tts': { const {details: {text, voice}} = info; audio = this.createTextToSpeechAudio(text, voice); } break; default: throw new Error(`Unsupported type: ${info.type}`); } } catch (e) { continue; } this._cache.set(key, {audio, source}); return {audio, index: i}; } throw new Error('Could not create audio'); } createAudio(url) { return new Promise((resolve, reject) => { const audio = new Audio(url); audio.addEventListener('loadeddata', () => { if (!this._isAudioValid(audio)) { reject(new Error('Could not retrieve audio')); } else { resolve(audio); } }); audio.addEventListener('error', () => reject(audio.error)); }); } createTextToSpeechAudio(text, voiceUri) { const voice = this._getTextToSpeechVoiceFromVoiceUri(voiceUri); if (voice === null) { throw new Error('Invalid text-to-speech voice'); } return new TextToSpeechAudio(text, voice); } // Private _isAudioValid(audio) { const duration = audio.duration; return ( duration !== 5.694694 && // jpod101 invalid audio (Chrome) duration !== 5.720718 // jpod101 invalid audio (Firefox) ); } _getTextToSpeechVoiceFromVoiceUri(voiceUri) { try { for (const voice of speechSynthesis.getVoices()) { if (voice.voiceURI === voiceUri) { return voice; } } } catch (e) { // NOP } return null; } }