/* * Copyright (C) 2023-2024 Yomitan Authors * Copyright (C) 2020-2022 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/>. */ import {EventDispatcher} from '../core/event-dispatcher.js'; /** * @augments EventDispatcher<import('clipboard-monitor').Events> */ export class ClipboardMonitor extends EventDispatcher { /** * @param {import('clipboard-monitor').ClipboardReaderLike} clipboardReader */ constructor(clipboardReader) { super(); /** @type {import('clipboard-monitor').ClipboardReaderLike} */ this._clipboardReader = clipboardReader; /** @type {?import('core').Timeout} */ this._timerId = null; /** @type {?import('core').TokenObject} */ this._timerToken = null; /** @type {number} */ this._interval = 250; /** @type {?string} */ this._previousText = null; } /** * @returns {void} */ start() { this.stop(); let canChange = false; /** * This token 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 call * will exit early if the reference has changed. * @type {?import('core').TokenObject} */ const token = {}; const intervalCallback = async () => { this._timerId = null; let text = null; try { text = await this._clipboardReader.getText(false); } catch (e) { // NOP } if (this._timerToken !== token) { return; } if ( typeof text === 'string' && (text = text.trim()).length > 0 && text !== this._previousText ) { this._previousText = text; if (canChange) { this.trigger('change', {text}); } } canChange = true; this._timerId = setTimeout(intervalCallback, this._interval); }; this._timerToken = token; void intervalCallback(); } /** * @returns {void} */ stop() { this._timerToken = null; this._previousText = null; if (this._timerId !== null) { clearTimeout(this._timerId); this._timerId = null; } } /** * @param {?string} text */ setPreviousText(text) { this._previousText = text; } }