Translate a webpage Translation with built-in AI into your preferred language, making browsing easier and faster.
// ==UserScript==
// @name Enhanced Translation
// @namespace your-namespace
// @description Translate a webpage Translation with built-in AI into your preferred language, making browsing easier and faster.
// @version 1.5
// @author UniverseDev
// @license GPL-3.0-or-later
// @match *://*/*
// @grant none
// ==/UserScript==
(async function () {
'use strict';
const CONFIG = {
targetLanguage: 'en',
debugMode: true,
translationAttribute: 'data-gm-translated',
excludedElementsSelector: 'code, pre, .notranslate, img, svg, video, audio, kbd, samp, var, math, noscript, script, style',
translationBatchSize: 250, // Reduced batch size for smoother updates
dynamicContentDebounceDelay: 300,
translationQueueDebounceDelay: 100, // Debounce for the translation queue processing
textContainingElementsSelector: 'p, h1, h2, h3, h4, h5, h6, span, a, div, li, dt, dd, blockquote, th, td, summary, figcaption, label, button, textarea, select, option, sr-only',
translatableAttributes: ['title', 'placeholder', 'alt', 'aria-label'],
loadingIndicatorStyle: `
position: fixed;
top: 10px;
left: 10px;
background-color: rgba(0, 0, 0, 0.7);
color: white;
padding: 8px 15px;
border-radius: 5px;
z-index: 10000;
font-size: 14px;
`,
loadingIndicatorText: 'Translating Initial Visible Content...', // Updated initial text
loadingIndicatorUpdatingText: (translatedCount, queueSize) => `Translating... (${translatedCount} translated, ${queueSize} in queue)`, // More informative
useIntersectionObserver: true,
intersectionObserverOptions: {
rootMargin: '0px',
threshold: 0.1
},
showErrorBanners: false, // Option to disable error banners
useTurboMode: true, // NEW: Turbo mode for faster translation
};
let dynamicContentTimer;
let translationQueueTimer;
let pageLanguage;
let loadingIndicator;
let translatedElementCount = 0;
const translationQueue = new Set();
let isIdleCallbackRunning = false;
let intersectionObserver;
let langAttributeObserver;
const targetLanguageCode = CONFIG.targetLanguage.toLowerCase(); // More descriptive variable name
const isTrulyVisibleCache = new WeakMap();
const domManipulationQueue = [];
// Track active translators and detectors to allow for destruction
const activeTranslators = new Map();
const activeDetectors = new Map();
function logDebug(message, ...args) {
if (CONFIG.debugMode) {
console.log(`${new Date().toLocaleTimeString()} - DEBUG: ${message}`, ...args);
}
}
function normalizeLang(lang) {
return lang ? lang.toLowerCase().split('-')[0] : '';
}
function showTranslationError(message) {
if (CONFIG.showErrorBanners) {
const errorBanner = document.createElement('div');
errorBanner.style.cssText = `position: fixed; bottom: 0; width: 100%; background-color: #f44336; color: #fff; text-align: center; padding: 10px; z-index: 9999;`;
errorBanner.textContent = `Translation Error: ${message}`;
document.body.appendChild(errorBanner);
setTimeout(() => errorBanner.remove(), 5000);
}
console.error(`Translation Error: ${message}`);
}
const isTranslationSupported = (() => {
try {
return 'translation' in self && typeof self.translation.createTranslator === 'function';
} catch (error) {
console.error("Error checking translation API:", error);
return false;
}
})();
if (!isTranslationSupported) {
logDebug("Translation features are unavailable.");
return;
}
let globalLanguageDetector = null;
async function getLanguageDetector(options = {}) {
if (globalLanguageDetector) {
return globalLanguageDetector;
}
try {
const controller = new AbortController();
const detector = await self.translation.createDetector({ signal: options.signal });
activeDetectors.set(detector, controller);
globalLanguageDetector = detector;
return detector;
} catch (error) {
logDebug(`Error creating language detector: ${error.message}`);
if (error.name !== 'AbortError') {
showTranslationError(error.message);
}
return null;
}
}
async function destroyLanguageDetector() {
if (globalLanguageDetector) {
const controller = activeDetectors.get(globalLanguageDetector);
if (controller) {
controller.abort();
activeDetectors.delete(globalLanguageDetector);
}
globalLanguageDetector.destroy();
globalLanguageDetector = null;
logDebug('Language detector destroyed and resources released.');
}
}
async function detectLanguage(text) { // Centralized language detection
const detector = await getLanguageDetector();
if (!detector) return 'unknown';
try {
const detectionResult = (await detector.detect(text))[0];
if (!detectionResult || detectionResult.confidence < 0.5) {
logDebug(`Detected language uncertain: ${detectionResult?.detectedLanguage}, confidence: ${detectionResult?.confidence}`);
return 'unknown';
}
logDebug(`Detected source language: ${detectionResult.detectedLanguage}, confidence: ${(detectionResult.confidence * 100).toFixed(1)}%`);
return normalizeLang(detectionResult.detectedLanguage) || 'unknown';
} catch (error) {
logDebug(`Language detection error: ${error}`);
return 'unknown';
}
}
const translatorCache = new Map();
async function getTranslator(sourceLang, options = {}) {
const key = `${sourceLang}-${targetLanguageCode}`;
if (translatorCache.has(key)) {
return translatorCache.get(key);
}
try {
const controller = new AbortController();
const translator = await self.translation.createTranslator({
sourceLanguage: sourceLang,
targetLanguage: targetLanguageCode,
signal: options.signal
});
activeTranslators.set(translator, controller);
translatorCache.set(key, translator);
return translator;
} catch (error) {
logDebug(`Error creating translator for ${key}: ${error.message}`);
if (error.name !== 'AbortError') {
showTranslationError(error.message);
}
return null;
}
}
async function destroyTranslator(translator) {
if (activeTranslators.has(translator)) {
const controller = activeTranslators.get(translator);
controller.abort(); // Abort any ongoing operations
activeTranslators.delete(translator);
for (const [key, cachedTranslator] of translatorCache.entries()) {
if (cachedTranslator === translator) {
translatorCache.delete(key);
break;
}
}
translator.destroy();
logDebug('Translator destroyed and resources released.');
}
}
async function destroyAllTranslators() {
for (const translator of activeTranslators.keys()) {
await destroyTranslator(translator);
}
}
async function translateContent(text, sourceLang, options = {}) {
if (!text || text.trim() === '') {
return text;
}
const translator = await getTranslator(sourceLang, { signal: options.signal });
if (!translator || typeof translator.translate !== 'function') {
logDebug("Translation API's `translate` method not found or invalid.");
return text;
}
try {
return await translator.translate(text, { signal: options.signal });
} catch (error) {
logDebug(`Error during translation: ${error.message}`);
if (error.name !== 'AbortError') {
showTranslationError(error.message);
}
return text;
}
}
function isTrulyVisible(element) {
if (!element) return false;
if (isTrulyVisibleCache.has(element)) {
return isTrulyVisibleCache.get(element);
}
const style = window.getComputedStyle(element);
const isVisible = style.display !== 'none' && style.visibility !== 'hidden' && parseFloat(style.opacity) > 0 && element.offsetParent !== null;
isTrulyVisibleCache.set(element, isVisible);
return isVisible;
}
function queueDOMManipulation(callback) {
domManipulationQueue.push(callback);
if (domManipulationQueue.length === 1) {
requestAnimationFrame(processDOMManipulationQueue);
}
}
function processDOMManipulationQueue() {
while (domManipulationQueue.length > 0) {
const callback = domManipulationQueue.shift();
callback();
}
}
async function translateTextNode(node, sourceLang, options = {}) {
if (node.nodeType === Node.TEXT_NODE && node.textContent.trim()) {
const originalText = node.textContent;
const translatedText = await translateContent(originalText, sourceLang, options);
if (translatedText && translatedText !== originalText) {
queueDOMManipulation(() => {
node.textContent = translatedText;
logDebug(`Translated text node: "${originalText}" to "${translatedText}"`);
});
}
}
}
async function translateAttributes(element, sourceLang, options = {}) {
let didTranslate = false;
const translations = {};
for (const attribute of CONFIG.translatableAttributes) {
if (element.hasAttribute(attribute)) {
const originalValue = element.getAttribute(attribute);
const translatedValue = await translateContent(originalValue, sourceLang, options);
if (translatedValue && translatedValue !== originalValue) {
translations[attribute] = translatedValue;
didTranslate = true;
}
}
}
if (Object.keys(translations).length > 0) {
queueDOMManipulation(() => {
for (const attribute in translations) {
element.setAttribute(attribute, translations[attribute]);
logDebug(`Translated ${attribute}: "${element.getAttribute(attribute)}" to "${translations[attribute]}"`);
}
});
}
return didTranslate;
}
async function translateElementContent(element, sourceLang, options = {}) {
const textNodePromises = [];
for (const node of element.childNodes) {
if (node.nodeType === Node.TEXT_NODE) {
const originalText = node.textContent;
const translatedTextPromise = translateContent(originalText, sourceLang, options);
textNodePromises.push(translatedTextPromise);
translatedTextPromise.then(translatedText => {
if (translatedText && translatedText !== originalText) {
queueDOMManipulation(() => {
node.textContent = translatedText;
logDebug(`Translated text node: "${originalText}" to "${translatedText}"`);
});
}
});
}
}
const results = await Promise.all(textNodePromises);
return results.some(translatedText => translatedText !== undefined);
}
function shouldTranslateElement(element) {
return isTrulyVisible(element) && !element.hasAttribute(CONFIG.translationAttribute);
}
async function translateElement(element) {
if (!shouldTranslateElement(element)) {
return;
}
let needsTranslation = false;
let sourceLang = pageLanguage;
const elementLang = normalizeLang(element.closest('[lang]')?.lang);
if (elementLang && elementLang !== targetLanguageCode) {
sourceLang = elementLang;
needsTranslation = true;
logDebug(`Using element-level language: ${sourceLang} for`, element);
} else if (!sourceLang) {
const textToDetect = element.textContent.substring(0, 200);
if (/\w+/.test(textToDetect)) {
const detectedLang = await detectLanguage(textToDetect);
if (detectedLang !== 'unknown' && normalizeLang(detectedLang) !== targetLanguageCode) {
sourceLang = detectedLang;
needsTranslation = true;
logDebug(`Detected element language: ${sourceLang} for`, element);
} else if (detectedLang === targetLanguageCode) {
queueDOMManipulation(() => element.setAttribute(CONFIG.translationAttribute, 'true'));
return;
}
} else {
queueDOMManipulation(() => element.setAttribute(CONFIG.translationAttribute, 'true'));
return;
}
} else if (normalizeLang(sourceLang) === targetLanguageCode) {
queueDOMManipulation(() => element.setAttribute(CONFIG.translationAttribute, 'true'));
return;
} else {
needsTranslation = true;
}
let contentTranslated = false;
let attributesTranslated = false;
if (needsTranslation) {
attributesTranslated = await translateAttributes(element, sourceLang);
contentTranslated = await translateElementContent(element, sourceLang);
}
if (needsTranslation && (contentTranslated || attributesTranslated)) {
queueDOMManipulation(() => {
element.setAttribute(CONFIG.translationAttribute, 'true');
});
}
translatedElementCount++;
requestAnimationFrame(() => {
if (loadingIndicator && typeof CONFIG.loadingIndicatorUpdatingText === 'function') {
loadingIndicator.textContent = CONFIG.loadingIndicatorUpdatingText(translatedElementCount, translationQueue.size);
}
});
}
async function processBatch(elements) {
if (CONFIG.useTurboMode) {
const translationPromises = elements.map(async (element) => {
if (isTrulyVisible(element)) {
await translateElement(element);
}
});
await Promise.all(translationPromises);
} else {
for (const element of elements) {
if (isTrulyVisible(element)) {
await translateElement(element);
}
}
}
}
function showLoadingIndicator() {
loadingIndicator = document.createElement('div');
loadingIndicator.style.cssText = CONFIG.loadingIndicatorStyle;
loadingIndicator.textContent = CONFIG.loadingIndicatorText;
document.body.appendChild(loadingIndicator);
}
function hideLoadingIndicator() {
if (loadingIndicator) {
loadingIndicator.remove();
loadingIndicator = null;
translatedElementCount = 0;
}
}
function queryShadowDOM(root, selector) {
let elements = Array.from(root.querySelectorAll(selector));
const shadowHosts = root.querySelectorAll('*');
shadowHosts.forEach(host => {
if (host.shadowRoot) {
elements = elements.concat(Array.from(queryShadowDOM(host.shadowRoot, selector))); // Convert NodeList to Array
}
});
return elements;
}
async function translateVisibleContent(elements) {
const visibleElementsToTranslate = elements.filter(el => isTrulyVisible(el));
logDebug(`Found ${visibleElementsToTranslate.length} initially visible elements to translate.`);
for (let i = 0; i < visibleElementsToTranslate.length; i += CONFIG.translationBatchSize) {
const batch = visibleElementsToTranslate.slice(i, i + CONFIG.translationBatchSize);
await processBatch(batch);
await new Promise(resolve => setTimeout(resolve, 0));
}
logDebug('Initial visible page content translation completed.');
hideLoadingIndicator();
}
async function translatePageContent() {
showLoadingIndicator();
pageLanguage = normalizeLang(document.documentElement.lang) || (await detectLanguage(document.body.innerText.substring(0, 500)));
logDebug(`Page language: ${pageLanguage}`);
logDebug(`Preferred language: ${targetLanguageCode}`);
if (pageLanguage === targetLanguageCode) {
logDebug('Page is already in the preferred language.');
hideLoadingIndicator();
return;
}
const elementsToTranslate = queryShadowDOM(document.body, `${CONFIG.textContainingElementsSelector}:not(${CONFIG.excludedElementsSelector}):not([${CONFIG.translationAttribute}])`);
logDebug(`Found ${elementsToTranslate.length} elements to potentially translate (initial).`);
if (CONFIG.useIntersectionObserver) {
initIntersectionObserver();
elementsToTranslate.forEach(element => {
if (isTrulyVisible(element)) {
intersectionObserver.observe(element);
}
});
logDebug('Observing initially visible elements with IntersectionObserver.');
} else {
await translateVisibleContent(elementsToTranslate);
}
}
function enqueueTranslatableElement(element) {
if (element && !element.matches(CONFIG.excludedElementsSelector) && !element.hasAttribute(CONFIG.translationAttribute) && isTrulyVisible(element)) {
translationQueue.add(element);
if (!isIdleCallbackRunning) {
isIdleCallbackRunning = true;
translationQueueTimer = setTimeout(processTranslationQueue, CONFIG.translationQueueDebounceDelay);
}
}
}
async function processTranslationQueue() {
isIdleCallbackRunning = false;
const elementsToProcess = Array.from(translationQueue);
translationQueue.clear();
if (CONFIG.useTurboMode) {
await Promise.all(elementsToProcess.map(translateElement));
} else {
for (const element of elementsToProcess) {
await translateElement(element);
}
}
}
function initIntersectionObserver() {
intersectionObserver = new IntersectionObserver((entries, observer) => {
entries.forEach(entry => {
if (entry.isIntersecting) {
const element = entry.target;
if (!element.hasAttribute(CONFIG.translationAttribute)) { // Ensure it hasn't been translated while waiting
enqueueTranslatableElement(element);
}
observer.unobserve(element); // Disconnect after enqueuing for translation
}
});
}, CONFIG.intersectionObserverOptions);
logDebug('IntersectionObserver initialized.');
}
async function translateAddedNode(node) {
if (node.nodeType === Node.ELEMENT_NODE) {
if (CONFIG.useIntersectionObserver) {
if (shouldTranslateElement(node)) {
intersectionObserver.observe(node);
}
} else if (isTrulyVisible(node)) {
enqueueTranslatableElement(node);
}
if (node.shadowRoot) {
const shadowElements = queryShadowDOM(node.shadowRoot, `*:not(${CONFIG.excludedElementsSelector}):not([${CONFIG.translationAttribute}])`);
shadowElements.forEach(el => {
if (CONFIG.useIntersectionObserver && isTrulyVisible(el)) {
intersectionObserver.observe(el);
} else if (!CONFIG.useIntersectionObserver && isTrulyVisible(el)) {
enqueueTranslatableElement(el);
}
});
}
node.querySelectorAll(`*:not(${CONFIG.excludedElementsSelector}):not([${CONFIG.translationAttribute}])`).forEach(child => {
if (CONFIG.useIntersectionObserver && isTrulyVisible(child)) {
intersectionObserver.observe(child);
} else if (!CONFIG.useIntersectionObserver && isTrulyVisible(child)) {
enqueueTranslatableElement(child);
}
});
} else if (node.nodeType === Node.TEXT_NODE && node.textContent.trim() && node.parentElement) {
if (CONFIG.useIntersectionObserver && isTrulyVisible(node.parentElement)) {
intersectionObserver.observe(node.parentElement);
} else if (!CONFIG.useIntersectionObserver && isTrulyVisible(node.parentElement)) {
enqueueTranslatableElement(node.parentElement);
}
}
}
async function handleChildListMutation(mutation) {
for (const addedNode of mutation.addedNodes) {
await translateAddedNode(addedNode);
}
}
async function handleCharacterDataMutation(mutation) {
if (mutation.target.parentNode && isTrulyVisible(mutation.target.parentNode)) {
enqueueTranslatableElement(mutation.target.parentNode);
}
}
async function handleAttributeMutation(mutation) {
if (mutation.target instanceof Element && CONFIG.translatableAttributes.includes(mutation.attributeName)) {
if (mutation.attributeName === 'style' || mutation.attributeName === 'class') {
isTrulyVisibleCache.delete(mutation.target);
}
if (isTrulyVisible(mutation.target)) {
enqueueTranslatableElement(mutation.target);
}
}
}
async function translateDynamicContent(mutationsList) {
for (const mutation of mutationsList) {
switch (mutation.type) {
case 'childList':
await handleChildListMutation(mutation);
break;
case 'characterData':
await handleCharacterDataMutation(mutation);
break;
case 'attributes':
await handleAttributeMutation(mutation);
break;
}
}
}
function observeDynamicContent() {
const observer = new MutationObserver(async (mutationsList) => {
if (mutationsList.length > 0) {
clearTimeout(dynamicContentTimer);
dynamicContentTimer = setTimeout(() => {
translateDynamicContent(mutationsList);
}, CONFIG.dynamicContentDebounceDelay);
}
});
observer.observe(document.body, {
childList: true,
subtree: true,
characterData: true,
attributeFilter: CONFIG.translatableAttributes.concat(['style', 'class']),
attributes: true,
});
logDebug('MutationObserver initialized for dynamic content.');
}
function initLangAttributeObserver() {
langAttributeObserver = new MutationObserver(mutationsList => {
mutationsList.forEach(mutation => {
if (mutation.type === 'attributes' && mutation.attributeName === 'lang') {
const element = mutation.target;
logDebug(`'lang' attribute changed on:`, element);
element.removeAttribute(CONFIG.translationAttribute);
if (isTrulyVisible(element)) {
enqueueTranslatableElement(element);
}
}
});
});
langAttributeObserver.observe(document.documentElement, {
attributes: true,
attributeFilter: ['lang'],
subtree: true
});
logDebug('Lang attribute observer initialized.');
}
// Global cleanup function to destroy resources
async function cleanup() {
logDebug('Cleaning up translation resources...');
await destroyAllTranslators();
await destroyLanguageDetector();
if (intersectionObserver) {
intersectionObserver.disconnect();
}
if (langAttributeObserver) {
langAttributeObserver.disconnect();
}
// Optionally disconnect the dynamic content observer if you keep a reference to it.
logDebug('Translation resources cleaned up.');
}
window.addEventListener('beforeunload', cleanup);
window.addEventListener('unload', cleanup);
window.addEventListener('load', async () => {
if (isTranslationSupported) {
await translatePageContent();
observeDynamicContent();
initLangAttributeObserver();
}
});
})();