1 files changed, 241 insertions, 0 deletions
diff --git a/ext/js/yomitan.js b/ext/js/yomitan.js
new file mode 100644
index 00000000..5535aeb6
--- /dev/null
+++ b/ext/js/yomitan.js
@@ -0,0 +1,241 @@
+/*
+ * Copyright (C) 2023  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 {API} from './comm/api.js';
+import {CrossFrameAPI} from './comm/cross-frame-api.js';
+import {EventDispatcher, deferPromise, invokeMessageHandler, log, serializeError} from './core.js';
+
+// Set up chrome alias if it's not available (Edge Legacy)
+if ((() => {
+    let hasChrome = false;
+    let hasBrowser = false;
+    try {
+        hasChrome = (typeof chrome === 'object' && chrome !== null && typeof chrome.runtime !== 'undefined');
+    } catch (e) {
+        // NOP
+    }
+    try {
+        hasBrowser = (typeof browser === 'object' && browser !== null && typeof browser.runtime !== 'undefined');
+    } catch (e) {
+        // NOP
+    }
+    return (hasBrowser && !hasChrome);
+})()) {
+    chrome = browser;
+}
+
+/**
+ * The Yomitan class is a core component through which various APIs are handled and invoked.
+ */
+class Yomitan extends EventDispatcher {
+    /**
+     * Creates a new instance. The instance should not be used until it has been fully prepare()'d.
+     */
+    constructor() {
+        super();
+
+        try {
+            const manifest = chrome.runtime.getManifest();
+            this._extensionName = `${manifest.name} v${manifest.version}`;
+        } catch (e) {
+            this._extensionName = 'Yomitan';
+        }
+
+        try {
+            this._extensionUrlBase = chrome.runtime.getURL('/');
+        } catch (e) {
+            this._extensionUrlBase = null;
+        }
+
+        this._isBackground = null;
+        this._api = null;
+        this._crossFrame = null;
+        this._isExtensionUnloaded = false;
+        this._isTriggeringExtensionUnloaded = false;
+        this._isReady = false;
+
+        const {promise, resolve} = deferPromise();
+        this._isBackendReadyPromise = promise;
+        this._isBackendReadyPromiseResolve = resolve;
+
+        this._messageHandlers = new Map([
+            ['Yomitan.isReady',         {async: false, handler: this._onMessageIsReady.bind(this)}],
+            ['Yomitan.backendReady',    {async: false, handler: this._onMessageBackendReady.bind(this)}],
+            ['Yomitan.getUrl',          {async: false, handler: this._onMessageGetUrl.bind(this)}],
+            ['Yomitan.optionsUpdated',  {async: false, handler: this._onMessageOptionsUpdated.bind(this)}],
+            ['Yomitan.databaseUpdated', {async: false, handler: this._onMessageDatabaseUpdated.bind(this)}],
+            ['Yomitan.zoomChanged',     {async: false, handler: this._onMessageZoomChanged.bind(this)}]
+        ]);
+    }
+
+    /**
+     * Whether the current frame is the background page/service worker or not.
+     * @type {boolean}
+     */
+    get isBackground() {
+        return this._isBackground;
+    }
+
+    /**
+     * Whether or not the extension is unloaded.
+     * @type {boolean}
+     */
+    get isExtensionUnloaded() {
+        return this._isExtensionUnloaded;
+    }
+
+    /**
+     * Gets the API instance for communicating with the backend.
+     * This value will be null on the background page/service worker.
+     * @type {API}
+     */
+    get api() {
+        return this._api;
+    }
+
+    /**
+     * Gets the CrossFrameAPI instance for communicating with different frames.
+     * This value will be null on the background page/service worker.
+     * @type {CrossFrameAPI}
+     */
+    get crossFrame() {
+        return this._crossFrame;
+    }
+
+    /**
+     * Prepares the instance for use.
+     * @param {boolean} [isBackground=false] Assigns whether this instance is being used from the background page/service worker.
+     */
+    async prepare(isBackground=false) {
+        this._isBackground = isBackground;
+        chrome.runtime.onMessage.addListener(this._onMessage.bind(this));
+
+        if (!isBackground) {
+            this._api = new API(this);
+
+            this.sendMessage({action: 'requestBackendReadySignal'});
+            await this._isBackendReadyPromise;
+
+            this._crossFrame = new CrossFrameAPI();
+            await this._crossFrame.prepare();
+
+            log.on('log', this._onForwardLog.bind(this));
+        }
+    }
+
+    /**
+     * Sends a message to the backend indicating that the frame is ready and all script
+     * setup has completed.
+     */
+    ready() {
+        this._isReady = true;
+        this.sendMessage({action: 'yomitanReady'});
+    }
+
+    /**
+     * Checks whether or not a URL is an extension URL.
+     * @param {string} url The URL to check.
+     * @returns {boolean} `true` if the URL is an extension URL, `false` otherwise.
+     */
+    isExtensionUrl(url) {
+        return this._extensionUrlBase !== null && url.startsWith(this._extensionUrlBase);
+    }
+
+    /**
+     * Runs `chrome.runtime.sendMessage()` with additional exception handling events.
+     * @param {...*} args The arguments to be passed to `chrome.runtime.sendMessage()`.
+     * @returns {void} The result of the `chrome.runtime.sendMessage()` call.
+     * @throws {Error} Errors thrown by `chrome.runtime.sendMessage()` are re-thrown.
+     */
+    sendMessage(...args) {
+        try {
+            return chrome.runtime.sendMessage(...args);
+        } catch (e) {
+            this.triggerExtensionUnloaded();
+            throw e;
+        }
+    }
+
+    triggerExtensionUnloaded() {
+        this._isExtensionUnloaded = true;
+        if (this._isTriggeringExtensionUnloaded) { return; }
+        try {
+            this._isTriggeringExtensionUnloaded = true;
+            this.trigger('extensionUnloaded');
+        } finally {
+            this._isTriggeringExtensionUnloaded = false;
+        }
+    }
+
+    // Private
+
+    _getUrl() {
+        return location.href;
+    }
+
+    _getLogContext() {
+        return {url: this._getUrl()};
+    }
+
+    _onMessage({action, params}, sender, callback) {
+        const messageHandler = this._messageHandlers.get(action);
+        if (typeof messageHandler === 'undefined') { return false; }
+        return invokeMessageHandler(messageHandler, params, callback, sender);
+    }
+
+    _onMessageIsReady() {
+        return this._isReady;
+    }
+
+    _onMessageBackendReady() {
+        if (this._isBackendReadyPromiseResolve === null) { return; }
+        this._isBackendReadyPromiseResolve();
+        this._isBackendReadyPromiseResolve = null;
+    }
+
+    _onMessageGetUrl() {
+        return {url: this._getUrl()};
+    }
+
+    _onMessageOptionsUpdated({source}) {
+        if (source !== 'background') {
+            this.trigger('optionsUpdated', {source});
+        }
+    }
+
+    _onMessageDatabaseUpdated({type, cause}) {
+        this.trigger('databaseUpdated', {type, cause});
+    }
+
+    _onMessageZoomChanged({oldZoomFactor, newZoomFactor}) {
+        this.trigger('zoomChanged', {oldZoomFactor, newZoomFactor});
+    }
+
+    async _onForwardLog({error, level, context}) {
+        try {
+            await this._api.log(serializeError(error), level, context);
+        } catch (e) {
+            // NOP
+        }
+    }
+}
+
+/**
+ * The default Yomitan class instance.
+ */
+export const yomitan = new Yomitan();