Merge pull request #2436 from SillyTavern/translation-improvements

Translation improvements

public/script.js

@@ -209,7 +209,7 @@ import {
     instruct_presets,
     selectContextPreset,
 } from './scripts/instruct-mode.js';
-import { initLocales } from './scripts/i18n.js';
+import { initLocales, t, translate } from './scripts/i18n.js';
 import { getFriendlyTokenizerName, getTokenCount, getTokenCountAsync, getTokenizerModel, initTokenizers, saveTokenCache } from './scripts/tokenizers.js';
 import {
     user_avatar,
@@ -7826,6 +7826,8 @@ window['SillyTavern'].getContext = function () {
         messageFormatting: messageFormatting,
         shouldSendOnEnter: shouldSendOnEnter,
         isMobile: isMobile,
+        t: t,
+        translate: translate,
         tags: tags,
         tagMap: tag_map,
         menuType: menu_type,

public/scripts/i18n.js

@@ -9,6 +9,71 @@ const langs = await fetch('/locales/lang.json').then(response => response.json()
 // eslint-disable-next-line prefer-const
 var localeData = await getLocaleData(localeFile);
 
+/**
+ * An observer that will check if any new i18n elements are added to the document
+ * @type {MutationObserver}
+ */
+const observer = new MutationObserver(mutations => {
+    mutations.forEach(mutation => {
+        mutation.addedNodes.forEach(node => {
+            if (node.nodeType === Node.ELEMENT_NODE && node instanceof Element) {
+                if (node.hasAttribute('data-i18n')) {
+                    translateElement(node);
+                }
+                node.querySelectorAll('[data-i18n]').forEach(element => {
+                    translateElement(element);
+                });
+            }
+        });
+        if (mutation.attributeName === 'data-i18n' && mutation.target instanceof Element) {
+            translateElement(mutation.target);
+        }
+    });
+});
+
+/**
+ * Translates a template string with named arguments
+ *
+ * Uses the template literal with all values replaced by index placeholder for translation key.
+ *
+ * @example
+ * ```js
+ * toastr.warn(t`Tag ${tagName} not found.`);
+ * ```
+ * Should be translated in the translation files as:
+ * ```
+ * Tag ${0} not found. -> Tag ${0} nicht gefunden.
+ * ```
+ *
+ * @param {TemplateStringsArray} strings - Template strings array
+ * @param  {...any} values - Values for placeholders in the template string
+ * @returns {string} Translated and formatted string
+ */
+export function t(strings, ...values) {
+    let str = strings.reduce((result, string, i) => result + string + (values[i] !== undefined ? `\${${i}}` : ''), '');
+    let translatedStr = translate(str);
+
+    // Replace indexed placeholders with actual values
+    return translatedStr.replace(/\$\{(\d+)\}/g, (match, index) => values[index]);
+}
+
+/**
+ * Translates a given key or text
+ *
+ * If the translation is based on a key, that one is used to find a possible translation in the translation file.
+ * The original text still has to be provided, as that is the default value being returned if no translation is found.
+ *
+ * For in-code text translation on a format string, using the template literal `t` is preferred.
+ *
+ * @param {string} text - The text to translate
+ * @param {string?} key - The key to use for translation. If not provided, text is used as the key.
+ * @returns {string} - The translated text
+ */
+export function translate(text, key = null) {
+    const translationKey = key || text;
+    return localeData?.[translationKey] || text;
+}
+
 /**
  * Fetches the locale data for the given language.
  * @param {string} language Language code
@@ -40,6 +105,29 @@ function findLang(language) {
     return supportedLang;
 }
 
+/**
+ * Translates a given element based on its data-i18n attribute.
+ * @param {Element} element The element to translate
+ */
+function translateElement(element) {
+    const keys = element.getAttribute('data-i18n').split(';'); // Multi-key entries are ; delimited
+    for (const key of keys) {
+        const attributeMatch = key.match(/\[(\S+)\](.+)/); // [attribute]key
+        if (attributeMatch) { // attribute-tagged key
+            const localizedValue = localeData?.[attributeMatch[2]];
+            if (localizedValue || localizedValue === '') {
+                element.setAttribute(attributeMatch[1], localizedValue);
+            }
+        } else { // No attribute tag, treat as 'text'
+            const localizedValue = localeData?.[key];
+            if (localizedValue || localizedValue === '') {
+                element.textContent = localizedValue;
+            }
+        }
+    }
+}
+
+
 async function getMissingTranslations() {
     const missingData = [];
 
@@ -103,22 +191,7 @@ export function applyLocale(root = document) {
 
     //find all the elements with `data-i18n` attribute
     $root.find('[data-i18n]').each(function () {
-        //read the translation from the language data
-        const keys = $(this).data('i18n').split(';'); // Multi-key entries are ; delimited
-        for (const key of keys) {
-            const attributeMatch = key.match(/\[(\S+)\](.+)/); // [attribute]key
-            if (attributeMatch) { // attribute-tagged key
-                const localizedValue = localeData?.[attributeMatch[2]];
-                if (localizedValue || localizedValue == '') {
-                    $(this).attr(attributeMatch[1], localizedValue);
-                }
-            } else { // No attribute tag, treat as 'text'
-                const localizedValue = localeData?.[key];
-                if (localizedValue || localizedValue == '') {
-                    $(this).text(localizedValue);
-                }
-            }
-        }
+        translateElement(this);
     });
 
     if (root !== document) {
@@ -126,7 +199,6 @@ export function applyLocale(root = document) {
     }
 }
 
-
 function addLanguagesToDropdown() {
     const uiLanguageSelects = $('#ui_language_select, #onboarding_ui_language_select');
     for (const langObj of langs) { // Set the value to the language code
@@ -159,6 +231,13 @@ export function initLocales() {
         location.reload();
     });
 
+    observer.observe(document, {
+        childList: true,
+        subtree: true,
+        attributes: true,
+        attributeFilter: ['data-i18n'],
+    });
+
     registerDebugFunction('getMissingTranslations', 'Get missing translations', 'Detects missing localization data in the current locale and dumps the data into the browser console. If the current locale is English, searches all other locales.', getMissingTranslations);
     registerDebugFunction('applyLocale', 'Apply locale', 'Reapplies the currently selected locale to the page.', applyLocale);
 }