Move bg/js (#1387)

* Move bg/js/anki.js to js/comm/anki.js

* Move bg/js/mecab.js to js/comm/mecab.js

* Move bg/js/search-main.js to js/display/search-main.js

* Move bg/js/template-patcher.js to js/templates/template-patcher.js

* Move bg/js/template-renderer-frame-api.js to js/templates/template-renderer-frame-api.js

* Move bg/js/template-renderer-frame-main.js to js/templates/template-renderer-frame-main.js

* Move bg/js/template-renderer-proxy.js to js/templates/template-renderer-proxy.js

* Move bg/js/template-renderer.js to js/templates/template-renderer.js

* Move bg/js/media-utility.js to js/media/media-utility.js

* Move bg/js/native-simple-dom-parser.js to js/dom/native-simple-dom-parser.js

* Move bg/js/simple-dom-parser.js to js/dom/simple-dom-parser.js

* Move bg/js/audio-downloader.js to js/media/audio-downloader.js

* Move bg/js/deinflector.js to js/language/deinflector.js

* Move bg/js/backend.js to js/background/backend.js

* Move bg/js/translator.js to js/language/translator.js

* Move bg/js/search-display-controller.js to js/display/search-display-controller.js

* Move bg/js/request-builder.js to js/background/request-builder.js

* Move bg/js/text-source-map.js to js/general/text-source-map.js

* Move bg/js/clipboard-reader.js to js/comm/clipboard-reader.js

* Move bg/js/clipboard-monitor.js to js/comm/clipboard-monitor.js

* Move bg/js/query-parser.js to js/display/query-parser.js

* Move bg/js/profile-conditions.js to js/background/profile-conditions.js

* Move bg/js/dictionary-database.js to js/language/dictionary-database.js

* Move bg/js/dictionary-importer.js to js/language/dictionary-importer.js

* Move bg/js/anki-note-builder.js to js/data/anki-note-builder.js

* Move bg/js/anki-note-data.js to js/data/anki-note-data.js

* Move bg/js/database.js to js/data/database.js

* Move bg/js/json-schema.js to js/data/json-schema.js

* Move bg/js/options.js to js/data/options-util.js

* Move bg/js/background-main.js to js/background/background-main.js

* Move bg/js/permissions-util.js to js/data/permissions-util.js

* Move bg/js/context-main.js to js/pages/action-popup-main.js

* Move bg/js/generic-page-main.js to js/pages/generic-page-main.js

* Move bg/js/info-main.js to js/pages/info-main.js

* Move bg/js/permissions-main.js to js/pages/permissions-main.js

* Move bg/js/welcome-main.js to js/pages/welcome-main.js

1 files changed, 230 insertions, 0 deletions

diff --git a/ext/js/comm/mecab.js b/ext/js/comm/mecab.js
new file mode 100644
index 00000000..4eff2927
--- /dev/null
+++ b/ext/js/comm/mecab.js
@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) 2019-2021  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/>.
+ */
+
+/**
+ * This class is used to connect Yomichan to a native component that is
+ * used to parse text into individual terms.
+ */
+class Mecab {
+    /**
+     * Creates a new instance of the class.
+     */
+    constructor() {
+        this._port = null;
+        this._sequence = 0;
+        this._invocations = new Map();
+        this._eventListeners = new EventListenerCollection();
+        this._timeout = 5000;
+        this._version = 1;
+        this._remoteVersion = null;
+        this._enabled = false;
+        this._setupPortPromise = null;
+    }
+
+    /**
+     * Returns whether or not the component is enabled.
+     */
+    isEnabled() {
+        return this._enabled;
+    }
+
+    /**
+     * Changes whether or not the component connection is enabled.
+     * @param enabled A boolean indicating whether or not the component should be enabled.
+     */
+    setEnabled(enabled) {
+        this._enabled = !!enabled;
+        if (!this._enabled && this._port !== null) {
+            this._clearPort();
+        }
+    }
+
+    /**
+     * Disconnects the current port, but does not disable future connections.
+     */
+    disconnect() {
+        if (this._port !== null) {
+            this._clearPort();
+        }
+    }
+
+    /**
+     * Returns whether or not the connection to the native application is active.
+     * @returns `true` if the connection is active, `false` otherwise.
+     */
+    isConnected() {
+        return (this._port !== null);
+    }
+
+    /**
+     * Returns whether or not any invocation is currently active.
+     * @returns `true` if an invocation is active, `false` otherwise.
+     */
+    isActive() {
+        return (this._invocations.size > 0);
+    }
+
+    /**
+     * Gets the local API version being used.
+     * @returns An integer representing the API version that Yomichan uses.
+     */
+    getLocalVersion() {
+        return this._version;
+    }
+
+    /**
+     * Gets the version of the MeCab component.
+     * @returns The version of the MeCab component, or `null` if the component was not found.
+     */
+    async getVersion() {
+        try {
+            await this._setupPort();
+        } catch (e) {
+            // NOP
+        }
+        return this._remoteVersion;
+    }
+
+    /**
+     * Parses a string of Japanese text into arrays of lines and terms.
+     *
+     * Return value format:
+     * ```js
+     * [
+     *     {
+     *         name: (string),
+     *         lines: [
+     *             {expression: (string), reading: (string), source: (string)},
+     *             ...
+     *         ]
+     *     },
+     *     ...
+     * ]
+     * ```
+     * @param text The string to parse.
+     * @returns A collection of parsing results of the text.
+     */
+    async parseText(text) {
+        await this._setupPort();
+        const rawResults = await this._invoke('parse_text', {text});
+        return this._convertParseTextResults(rawResults);
+    }
+
+    // Private
+
+    _onMessage({sequence, data}) {
+        const invocation = this._invocations.get(sequence);
+        if (typeof invocation === 'undefined') { return; }
+
+        const {resolve, timer} = invocation;
+        clearTimeout(timer);
+        resolve(data);
+        this._invocations.delete(sequence);
+    }
+
+    _onDisconnect() {
+        if (this._port === null) { return; }
+        const e = chrome.runtime.lastError;
+        const error = new Error(e ? e.message : 'MeCab disconnected');
+        for (const {reject, timer} of this._invocations.values()) {
+            clearTimeout(timer);
+            reject(error);
+        }
+        this._clearPort();
+    }
+
+    _invoke(action, params) {
+        return new Promise((resolve, reject) => {
+            if (this._port === null) {
+                reject(new Error('Port disconnected'));
+            }
+
+            const sequence = this._sequence++;
+
+            const timer = setTimeout(() => {
+                this._invocations.delete(sequence);
+                reject(new Error(`MeCab invoke timed out after ${this._timeout}ms`));
+            }, this._timeout);
+
+            this._invocations.set(sequence, {resolve, reject, timer}, this._timeout);
+
+            this._port.postMessage({action, params, sequence});
+        });
+    }
+
+    _convertParseTextResults(rawResults) {
+        const results = [];
+        for (const [name, rawLines] of Object.entries(rawResults)) {
+            const lines = [];
+            for (const rawLine of rawLines) {
+                const line = [];
+                for (let {expression, reading, source} of rawLine) {
+                    if (typeof expression !== 'string') { expression = ''; }
+                    if (typeof reading !== 'string') { reading = ''; }
+                    if (typeof source !== 'string') { source = ''; }
+                    line.push({expression, reading, source});
+                }
+                lines.push(line);
+            }
+            results.push({name, lines});
+        }
+        return results;
+    }
+
+    async _setupPort() {
+        if (!this._enabled) {
+            throw new Error('MeCab not enabled');
+        }
+        if (this._setupPortPromise === null) {
+            this._setupPortPromise = this._setupPort2();
+        }
+        try {
+            await this._setupPortPromise;
+        } catch (e) {
+            throw new Error(e.message);
+        }
+    }
+
+    async _setupPort2() {
+        const port = chrome.runtime.connectNative('yomichan_mecab');
+        this._eventListeners.addListener(port.onMessage, this._onMessage.bind(this));
+        this._eventListeners.addListener(port.onDisconnect, this._onDisconnect.bind(this));
+        this._port = port;
+
+        try {
+            const {version} = await this._invoke('get_version', {});
+            this._remoteVersion = version;
+            if (version !== this._version) {
+                throw new Error(`Unsupported MeCab native messenger version ${version}. Yomichan supports version ${this._version}.`);
+            }
+        } catch (e) {
+            if (this._port === port) {
+                this._clearPort();
+            }
+            throw e;
+        }
+    }
+
+    _clearPort() {
+        this._port.disconnect();
+        this._port = null;
+        this._invocations.clear();
+        this._eventListeners.removeAllEventListeners();
+        this._sequence = 0;
+        this._setupPortPromise = null;
+    }
+}