/* * Copyright (C) 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/>. */ class FrameClient { constructor() { this._secret = null; this._token = null; this._frameId = null; } get frameId() { return this._frameId; } async connect(frame, targetOrigin, hostFrameId, setupFrame, timeout=10000) { const {secret, token, frameId} = await this._connectIternal(frame, targetOrigin, hostFrameId, setupFrame, timeout); this._secret = secret; this._token = token; this._frameId = frameId; } isConnected() { return (this._secret !== null); } createMessage(data) { if (!this.isConnected()) { throw new Error('Not connected'); } return { token: this._token, secret: this._secret, data }; } _connectIternal(frame, targetOrigin, hostFrameId, setupFrame, timeout) { return new Promise((resolve, reject) => { const tokenMap = new Map(); let timer = null; let { promise: frameLoadedPromise, resolve: frameLoadedResolve, reject: frameLoadedReject } = deferPromise(); const postMessage = (action, params) => { const contentWindow = frame.contentWindow; if (contentWindow === null) { throw new Error('Frame missing content window'); } let validOrigin = true; try { validOrigin = (contentWindow.location.origin === targetOrigin); } catch (e) { // NOP } if (!validOrigin) { throw new Error('Unexpected frame origin'); } contentWindow.postMessage({action, params}, targetOrigin); }; const onMessage = (message) => { onMessageInner(message); return false; }; const onMessageInner = async (message) => { try { if (!isObject(message)) { return; } const {action, params} = message; if (!isObject(params)) { return; } await frameLoadedPromise; if (timer === null) { return; } // Done switch (action) { case 'frameEndpointReady': { const {secret} = params; const token = yomichan.generateId(16); tokenMap.set(secret, token); postMessage('frameEndpointConnect', {secret, token, hostFrameId}); } break; case 'frameEndpointConnected': { const {secret, token} = params; const frameId = message.frameId; const token2 = tokenMap.get(secret); if (typeof token2 !== 'undefined' && token === token2) { cleanup(); resolve({secret, token, frameId}); } } break; } } catch (e) { cleanup(); reject(e); } }; const onLoad = () => { if (frameLoadedResolve === null) { cleanup(); reject(new Error('Unexpected load event')); return; } if (FrameClient.isFrameAboutBlank(frame)) { return; } frameLoadedResolve(); frameLoadedResolve = null; frameLoadedReject = null; }; const cleanup = () => { if (timer === null) { return; } // Done clearTimeout(timer); timer = null; frameLoadedResolve = null; if (frameLoadedReject !== null) { frameLoadedReject(new Error('Terminated')); frameLoadedReject = null; } chrome.runtime.onMessage.removeListener(onMessage); frame.removeEventListener('load', onLoad); }; // Start timer = setTimeout(() => { cleanup(); reject(new Error('Timeout')); }, timeout); chrome.runtime.onMessage.addListener(onMessage); frame.addEventListener('load', onLoad); // Prevent unhandled rejections frameLoadedPromise.catch(() => {}); // NOP setupFrame(frame); }); } static isFrameAboutBlank(frame) { try { const contentDocument = frame.contentDocument; if (contentDocument === null) { return false; } const url = contentDocument.location.href; return /^about:blank(?:[#?]|$)/.test(url); } catch (e) { return false; } } }