Files
SubMiner/vendor/yomitan/js/background/offscreen-proxy.js
2026-02-09 19:04:19 -08:00

319 lines
12 KiB
JavaScript

/*
* Copyright (C) 2023-2025 Yomitan Authors
* Copyright (C) 2016-2022 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 {ExtensionError} from '../core/extension-error.js';
import {isObjectNotArray} from '../core/object-utilities.js';
import {base64ToArrayBuffer} from '../data/array-buffer-util.js';
/**
* This class is responsible for creating and communicating with an offscreen document.
* This offscreen document is used to solve three issues:
*
* - Provide clipboard access for the `ClipboardReader` class in the context of a MV3 extension.
* The background service workers doesn't have access a webpage to read the clipboard from,
* so it must be done in the offscreen page.
*
* - Create a worker for image rendering, which both selects the images from the database,
* decodes/rasterizes them, and then sends (= postMessage transfers) them back to a worker
* in the popup to be rendered onto OffscreenCanvas.
*
* - Provide a longer lifetime for the dictionary database. The background service worker can be
* terminated by the web browser, which means that when it restarts, it has to go through its
* initialization process again. This initialization process can take a non-trivial amount of
* time, which is primarily caused by the startup of the IndexedDB database, especially when a
* large amount of dictionary data is installed.
*
* The offscreen document stays alive longer, potentially forever, which may be an artifact of
* the clipboard access it requests in the `reasons` parameter. Therefore, this initialization
* process should only take place once, or at the very least, less frequently than the service
* worker.
*
* The long lifetime of the offscreen document is not guaranteed by the spec, which could
* result in this code functioning poorly in the future if a web browser vendor changes the
* APIs or the implementation substantially, and this is even referenced on the Chrome
* developer website.
* @see https://developer.chrome.com/blog/Offscreen-Documents-in-Manifest-v3
* @see https://developer.chrome.com/docs/extensions/reference/api/offscreen
*/
export class OffscreenProxy {
/**
* @param {import('../extension/web-extension.js').WebExtension} webExtension
*/
constructor(webExtension) {
/** @type {import('../extension/web-extension.js').WebExtension} */
this._webExtension = webExtension;
/** @type {?Promise<void>} */
this._creatingOffscreen = null;
/** @type {?MessagePort} */
this._currentOffscreenPort = null;
}
/**
* @see https://developer.chrome.com/docs/extensions/reference/offscreen/
*/
async prepare() {
if (await this._hasOffscreenDocument()) {
void this.sendMessagePromise({action: 'createAndRegisterPortOffscreen'});
return;
}
if (this._creatingOffscreen) {
await this._creatingOffscreen;
return;
}
this._creatingOffscreen = chrome.offscreen.createDocument({
url: 'offscreen.html',
reasons: [
/** @type {chrome.offscreen.Reason} */ ('CLIPBOARD'),
],
justification: 'Access to the clipboard',
});
await this._creatingOffscreen;
this._creatingOffscreen = null;
}
/**
* @returns {Promise<boolean>}
*/
async _hasOffscreenDocument() {
const offscreenUrl = chrome.runtime.getURL('offscreen.html');
if (!chrome.runtime.getContexts) { // Chrome version below 116
// Clients: https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerGlobalScope/clients
// @ts-expect-error - Types not set up for service workers yet
// eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
const matchedClients = await clients.matchAll();
// @ts-expect-error - Types not set up for service workers yet
return await matchedClients.some((client) => client.url === offscreenUrl);
}
const contexts = await chrome.runtime.getContexts({
contextTypes: [
/** @type {chrome.runtime.ContextType} */ ('OFFSCREEN_DOCUMENT'),
],
documentUrls: [offscreenUrl],
});
return contexts.length > 0;
}
/**
* @template {import('offscreen').ApiNames} TMessageType
* @param {import('offscreen').ApiMessage<TMessageType>} message
* @returns {Promise<import('offscreen').ApiReturn<TMessageType>>}
*/
async sendMessagePromise(message) {
const response = await this._webExtension.sendMessagePromise(message);
return this._getMessageResponseResult(/** @type {import('core').Response<import('offscreen').ApiReturn<TMessageType>>} */ (response));
}
/**
* @template [TReturn=unknown]
* @param {import('core').Response<TReturn>} response
* @returns {TReturn}
* @throws {Error}
*/
_getMessageResponseResult(response) {
const runtimeError = chrome.runtime.lastError;
if (typeof runtimeError !== 'undefined') {
throw new Error(runtimeError.message);
}
if (!isObjectNotArray(response)) {
throw new Error('Offscreen document did not respond');
}
const responseError = response.error;
if (responseError) {
throw ExtensionError.deserialize(responseError);
}
return response.result;
}
/**
* @param {MessagePort} port
*/
async registerOffscreenPort(port) {
if (this._currentOffscreenPort) {
this._currentOffscreenPort.close();
}
this._currentOffscreenPort = port;
}
/**
* When you need to transfer Transferable objects, you can use this method which uses postMessage over the MessageChannel port established with the offscreen document.
* @template {import('offscreen').McApiNames} TMessageType
* @param {import('offscreen').McApiMessage<TMessageType>} message
* @param {Transferable[]} transfers
*/
sendMessageViaPort(message, transfers) {
if (this._currentOffscreenPort !== null) {
this._currentOffscreenPort.postMessage(message, transfers);
} else {
void this.sendMessagePromise({action: 'createAndRegisterPortOffscreen'});
}
}
}
export class DictionaryDatabaseProxy {
/**
* @param {OffscreenProxy} offscreen
*/
constructor(offscreen) {
/** @type {OffscreenProxy} */
this._offscreen = offscreen;
}
/**
* @returns {Promise<void>}
*/
async prepare() {
await this._offscreen.sendMessagePromise({action: 'databasePrepareOffscreen'});
}
/**
* @returns {Promise<import('dictionary-importer').Summary[]>}
*/
async getDictionaryInfo() {
return this._offscreen.sendMessagePromise({action: 'getDictionaryInfoOffscreen'});
}
/**
* @returns {Promise<boolean>}
*/
async purge() {
return await this._offscreen.sendMessagePromise({action: 'databasePurgeOffscreen'});
}
/**
* @param {import('dictionary-database').MediaRequest[]} targets
* @returns {Promise<import('dictionary-database').Media[]>}
*/
async getMedia(targets) {
const serializedMedia = /** @type {import('dictionary-database').Media<string>[]} */ (await this._offscreen.sendMessagePromise({action: 'databaseGetMediaOffscreen', params: {targets}}));
return serializedMedia.map((m) => ({...m, content: base64ToArrayBuffer(m.content)}));
}
/**
* @param {MessagePort} port
* @returns {Promise<void>}
*/
async connectToDatabaseWorker(port) {
this._offscreen.sendMessageViaPort({action: 'connectToDatabaseWorker'}, [port]);
}
}
export class TranslatorProxy {
/**
* @param {OffscreenProxy} offscreen
*/
constructor(offscreen) {
/** @type {OffscreenProxy} */
this._offscreen = offscreen;
}
/** */
async prepare() {
await this._offscreen.sendMessagePromise({action: 'translatorPrepareOffscreen'});
}
/**
* @param {string} text
* @param {import('translation').FindKanjiOptions} options
* @returns {Promise<import('dictionary').KanjiDictionaryEntry[]>}
*/
async findKanji(text, options) {
const enabledDictionaryMapList = [...options.enabledDictionaryMap];
/** @type {import('offscreen').FindKanjiOptionsOffscreen} */
const modifiedOptions = {
...options,
enabledDictionaryMap: enabledDictionaryMapList,
};
return this._offscreen.sendMessagePromise({action: 'findKanjiOffscreen', params: {text, options: modifiedOptions}});
}
/**
* @param {import('translator').FindTermsMode} mode
* @param {string} text
* @param {import('translation').FindTermsOptions} options
* @returns {Promise<import('translator').FindTermsResult>}
*/
async findTerms(mode, text, options) {
const {enabledDictionaryMap, excludeDictionaryDefinitions, textReplacements} = options;
const enabledDictionaryMapList = [...enabledDictionaryMap];
const excludeDictionaryDefinitionsList = excludeDictionaryDefinitions ? [...excludeDictionaryDefinitions] : null;
const textReplacementsSerialized = textReplacements.map((group) => {
return group !== null ? group.map((opt) => ({...opt, pattern: opt.pattern.toString()})) : null;
});
/** @type {import('offscreen').FindTermsOptionsOffscreen} */
const modifiedOptions = {
...options,
enabledDictionaryMap: enabledDictionaryMapList,
excludeDictionaryDefinitions: excludeDictionaryDefinitionsList,
textReplacements: textReplacementsSerialized,
};
return this._offscreen.sendMessagePromise({action: 'findTermsOffscreen', params: {mode, text, options: modifiedOptions}});
}
/**
* @param {import('translator').TermReadingList} termReadingList
* @param {string[]} dictionaries
* @returns {Promise<import('translator').TermFrequencySimple[]>}
*/
async getTermFrequencies(termReadingList, dictionaries) {
return this._offscreen.sendMessagePromise({action: 'getTermFrequenciesOffscreen', params: {termReadingList, dictionaries}});
}
/** */
async clearDatabaseCaches() {
await this._offscreen.sendMessagePromise({action: 'clearDatabaseCachesOffscreen'});
}
}
export class ClipboardReaderProxy {
/**
* @param {OffscreenProxy} offscreen
*/
constructor(offscreen) {
/** @type {?import('environment').Browser} */
this._browser = null;
/** @type {OffscreenProxy} */
this._offscreen = offscreen;
}
/** @type {?import('environment').Browser} */
get browser() { return this._browser; }
set browser(value) {
if (this._browser === value) { return; }
this._browser = value;
void this._offscreen.sendMessagePromise({action: 'clipboardSetBrowserOffscreen', params: {value}});
}
/**
* @param {boolean} useRichText
* @returns {Promise<string>}
*/
async getText(useRichText) {
return await this._offscreen.sendMessagePromise({action: 'clipboardGetTextOffscreen', params: {useRichText}});
}
/**
* @returns {Promise<?string>}
*/
async getImage() {
return await this._offscreen.sendMessagePromise({action: 'clipboardGetImageOffscreen'});
}
}