/* * Copyright (C) 2020 Alex Yatskov <alex@foosoft.net> * Author: Alex Yatskov <alex@foosoft.net> * * 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 apiClipboardGet, jpIsStringPartiallyJapanese*/ class ClipboardMonitor { constructor() { this.timerId = null; this.timerToken = null; this.interval = 250; this.previousText = null; } onClipboardText(_text) { throw new Error('Override me'); } start() { this.stop(); // The token below is used as a unique identifier to ensure that a new clipboard monitor // hasn't been started during the await call. The check below the await apiClipboardGet() // call will exit early if the reference has changed. const token = {}; const intervalCallback = async () => { this.timerId = null; let text = null; try { text = await apiClipboardGet(); } catch (e) { // NOP } if (this.timerToken !== token) { return; } if ( typeof text === 'string' && (text = text.trim()).length > 0 && text !== this.previousText ) { this.previousText = text; if (jpIsStringPartiallyJapanese(text)) { this.onClipboardText(text); } } this.timerId = setTimeout(intervalCallback, this.interval); }; this.timerToken = token; intervalCallback(); } stop() { this.timerToken = null; if (this.timerId !== null) { clearTimeout(this.timerId); this.timerId = null; } } setPreviousText(text) { this.previousText = text; } }