Add lazy widget language localization

server.js

@@ -23,6 +23,12 @@ const ALLOWED_IMAGE_EXTENSIONS = new Set([".jpg", ".jpeg", ".png", ".webp", ".gi
 const MAX_ATTACHMENT_BYTES = 3_000_000;
 const ACTIVE_VISITOR_SECONDS = 90;
 const PRESENT_VISITOR_SECONDS = 300;
+const WIDGET_COPY_FIELDS = ["title", "intro", "offlineIntro", "placeholder", "sendLabel", "dropzoneLabel", "onlineLabel", "offlineLabel", "newReplyLabel", "typingLabel", "infoTitle", "infoText", "closeLabel", "operatorReplyLabel"];
+const EUROPEAN_WIDGET_LANGUAGES = new Set([
+  "sq", "be", "bs", "bg", "ca", "hr", "cs", "da", "nl", "en", "et", "fi", "fr", "de", "el",
+  "hu", "is", "ga", "it", "lv", "lt", "mk", "mt", "no", "pl", "pt", "ro", "ru", "sr", "sk",
+  "sl", "es", "sv", "tr", "uk"
+]);
 
 fs.mkdirSync(DATA_DIR, { recursive: true });
 fs.mkdirSync(UPLOAD_DIR, { recursive: true });
@@ -286,12 +292,23 @@ function seedDefaults() {
 }
 
 function defaultSettings() {
+  const widgetCopy = {
+    cs: defaultWidgetCopy("cs"),
+    en: defaultWidgetCopy("en")
+  };
   return {
-    title: { cs: "Potrebujete poradit?", en: "Need help?" },
-    intro: { cs: "Napiste nam. Odpovime co nejdrive.", en: "Message us and we will reply as soon as possible." },
-    offlineIntro: { cs: "Ted nejsme online, ale zpravu nam muzete nechat.", en: "We are offline, but you can leave us a message." },
-    placeholder: { cs: "Napiste zpravu...", en: "Write a message..." },
-    sendLabel: { cs: "Odeslat", en: "Send" },
+    widgetLanguage: {
+      mode: "auto",
+      defaultLanguage: "cs",
+      fixedLanguage: "cs",
+      fallbackLanguage: "cs"
+    },
+    widgetCopy,
+    title: { cs: widgetCopy.cs.title, en: widgetCopy.en.title },
+    intro: { cs: widgetCopy.cs.intro, en: widgetCopy.en.intro },
+    offlineIntro: { cs: widgetCopy.cs.offlineIntro, en: widgetCopy.en.offlineIntro },
+    placeholder: { cs: widgetCopy.cs.placeholder, en: widgetCopy.en.placeholder },
+    sendLabel: { cs: widgetCopy.cs.sendLabel, en: widgetCopy.en.sendLabel },
     detailsLabel: { cs: "Kontaktni udaje", en: "Contact details" },
     colors: {
       brand: "#0f8f6f",
@@ -323,6 +340,43 @@ function defaultSettings() {
   };
 }
 
+function defaultWidgetCopy(language) {
+  if (language === "en") {
+    return {
+      title: "Need help?",
+      intro: "Message us and we will reply as soon as possible.",
+      offlineIntro: "We are offline, but you can leave us a message.",
+      placeholder: "Write a message...",
+      sendLabel: "Send",
+      dropzoneLabel: "Add a photo or drag it here",
+      onlineLabel: "We are online",
+      offlineLabel: "Offline",
+      newReplyLabel: "New reply",
+      typingLabel: "Operator is typing...",
+      infoTitle: "Privacy information",
+      infoText: "We process your message and technical session data only to answer your request.",
+      closeLabel: "Minimize chat",
+      operatorReplyLabel: "is replying"
+    };
+  }
+  return {
+    title: "Potrebujete poradit?",
+    intro: "Napiste nam. Odpovime co nejdrive.",
+    offlineIntro: "Ted nejsme online, ale zpravu nam muzete nechat.",
+    placeholder: "Napiste zpravu...",
+    sendLabel: "Odeslat",
+    dropzoneLabel: "Pridat fotku nebo pretahnout",
+    onlineLabel: "Jsme online",
+    offlineLabel: "Offline",
+    newReplyLabel: "Nova odpoved",
+    typingLabel: "Operator pise...",
+    infoTitle: "GDPR informace",
+    infoText: "Zpravu a technicke udaje relace zpracujeme jen pro odpoved na vas dotaz.",
+    closeLabel: "Zmensit chat",
+    operatorReplyLabel: "odpovida"
+  };
+}
+
 function configuredUsers() {
   const users = [];
   for (let i = 1; i < 50; i += 1) {
@@ -634,11 +688,13 @@ function deleteConversation(res, url) {
   return json(res, 200, { ok: true });
 }
 
-function widgetConfig(res, url) {
+async function widgetConfig(res, url) {
   const siteKey = url.searchParams.get("siteKey") || process.env.DEFAULT_SITE_KEY || "9b-plus";
   const site = db.prepare("SELECT * FROM sites WHERE site_key = ?").get(siteKey);
   if (!site) return json(res, 404, { error: "site_not_found" });
-  return json(res, 200, { site: formatSite(site), publicBaseUrl: PUBLIC_BASE_URL });
+  const language = widgetLanguageForRequest(site, url);
+  const copy = await widgetCopyForLanguage(site, language);
+  return json(res, 200, { site: formatSite(getSiteById(site.id)), publicBaseUrl: PUBLIC_BASE_URL, language: copy.language, copy: copy.copy });
 }
 
 async function visitorPing(req, res) {
@@ -1017,6 +1073,8 @@ function outputTextFromResponse(data) {
 
 function mergeSiteSettings(currentSettings, incomingSettings) {
   const settings = { ...currentSettings, ...incomingSettings };
+  settings.widgetLanguage = normalizeWidgetLanguageSettings(settings.widgetLanguage || currentSettings.widgetLanguage || {});
+  settings.widgetCopy = normalizeWidgetCopy(settings.widgetCopy || currentSettings.widgetCopy || {}, settings);
   const currentTranslations = currentSettings.translations || {};
   const incomingTranslations = incomingSettings.translations || {};
   settings.translations = {
@@ -1035,6 +1093,58 @@ function mergeSiteSettings(currentSettings, incomingSettings) {
   return settings;
 }
 
+function normalizeWidgetLanguageSettings(value) {
+  const defaults = defaultSettings().widgetLanguage;
+  const settings = { ...defaults, ...(value || {}) };
+  const mode = settings.mode === "fixed" ? "fixed" : "auto";
+  return {
+    mode,
+    defaultLanguage: allowedWidgetLanguage(settings.defaultLanguage) || defaults.defaultLanguage,
+    fixedLanguage: allowedWidgetLanguage(settings.fixedLanguage) || defaults.fixedLanguage,
+    fallbackLanguage: allowedWidgetLanguage(settings.fallbackLanguage) || allowedWidgetLanguage(settings.defaultLanguage) || defaults.fallbackLanguage
+  };
+}
+
+function normalizeWidgetCopy(value, settings = {}) {
+  const copy = { ...(value || {}) };
+  const legacyLanguages = new Set([
+    ...Object.keys(settings.title || {}),
+    ...Object.keys(settings.intro || {}),
+    ...Object.keys(settings.offlineIntro || {}),
+    ...Object.keys(settings.placeholder || {}),
+    ...Object.keys(settings.sendLabel || {})
+  ]);
+  for (const language of legacyLanguages) {
+    const lang = allowedWidgetLanguage(language);
+    if (!lang) continue;
+    copy[lang] = {
+      ...(copy[lang] || {}),
+      title: settings.title?.[lang],
+      intro: settings.intro?.[lang],
+      offlineIntro: settings.offlineIntro?.[lang],
+      placeholder: settings.placeholder?.[lang],
+      sendLabel: settings.sendLabel?.[lang]
+    };
+  }
+  copy.cs = normalizeWidgetCopyEntry(copy.cs || defaultWidgetCopy("cs"), "cs");
+  copy.en = normalizeWidgetCopyEntry(copy.en || defaultWidgetCopy("en"), "en");
+  for (const language of Object.keys(copy)) {
+    const lang = allowedWidgetLanguage(language);
+    if (!lang) delete copy[language];
+    else copy[lang] = normalizeWidgetCopyEntry(copy[language], lang);
+  }
+  return copy;
+}
+
+function normalizeWidgetCopyEntry(value, language) {
+  const defaults = defaultWidgetCopy(language === "en" ? "en" : "cs");
+  const copy = {};
+  for (const field of WIDGET_COPY_FIELDS) {
+    copy[field] = String(value?.[field] || defaults[field] || "").trim();
+  }
+  return copy;
+}
+
 function getTranslationSettings() {
   const site = getDefaultSite();
   const settings = parseJson(site.settings_json, defaultSettings());
@@ -1047,6 +1157,103 @@ function getTranslationSettings() {
   };
 }
 
+function widgetLanguageForRequest(site, url) {
+  const settings = parseJson(site.settings_json, defaultSettings());
+  const languageSettings = normalizeWidgetLanguageSettings(settings.widgetLanguage);
+  if (languageSettings.mode === "fixed") return languageSettings.fixedLanguage;
+  return allowedWidgetLanguage(url.searchParams.get("lang"))
+    || allowedWidgetLanguage(url.searchParams.get("pageLang"))
+    || languageFromUrl(url.searchParams.get("currentUrl"))
+    || allowedWidgetLanguage(url.searchParams.get("browserLang"))
+    || languageSettings.fallbackLanguage;
+}
+
+async function widgetCopyForLanguage(site, requestedLanguage) {
+  const settings = parseJson(site.settings_json, defaultSettings());
+  settings.widgetLanguage = normalizeWidgetLanguageSettings(settings.widgetLanguage);
+  settings.widgetCopy = normalizeWidgetCopy(settings.widgetCopy || {}, settings);
+
+  const language = allowedWidgetLanguage(requestedLanguage) || settings.widgetLanguage.fallbackLanguage;
+  if (settings.widgetCopy[language]) return { language, copy: settings.widgetCopy[language] };
+
+  const fallbackLanguage = settings.widgetCopy[settings.widgetLanguage.fallbackLanguage]
+    ? settings.widgetLanguage.fallbackLanguage
+    : settings.widgetLanguage.defaultLanguage;
+  const fallbackCopy = settings.widgetCopy[fallbackLanguage] || defaultWidgetCopy("cs");
+  const translated = await translateWidgetCopyOnce(fallbackCopy, fallbackLanguage, language);
+  if (!translated) return { language: fallbackLanguage, copy: fallbackCopy };
+
+  settings.widgetCopy[language] = translated;
+  syncLegacyWidgetCopy(settings);
+  db.prepare("UPDATE sites SET settings_json = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?").run(JSON.stringify(settings), site.id);
+  return { language, copy: translated };
+}
+
+async function translateWidgetCopyOnce(sourceCopy, sourceLanguage, targetLanguage) {
+  const settings = getTranslationSettings();
+  if (!settings.enabled || !settings.openaiApiKey || !targetLanguage || sourceLanguage === targetLanguage) return null;
+  try {
+    const response = await fetch("https://api.openai.com/v1/responses", {
+      method: "POST",
+      headers: {
+        "Authorization": `Bearer ${settings.openaiApiKey}`,
+        "Content-Type": "application/json"
+      },
+      body: JSON.stringify({
+        model: settings.model,
+        input: [
+          {
+            role: "system",
+            content: "Translate UI copy for a live chat widget. Return only compact JSON with the same keys. Preserve brand names and meaning. Keep labels short."
+          },
+          {
+            role: "user",
+            content: JSON.stringify({ sourceLanguage, targetLanguage, copy: sourceCopy })
+          }
+        ]
+      })
+    });
+    if (!response.ok) {
+      const openAiError = await openAiErrorFromResponse(response);
+      throw new Error(openAiError.message);
+    }
+    const data = await response.json();
+    return normalizeWidgetCopyEntry(parseJsonBlock(outputTextFromResponse(data)), targetLanguage);
+  } catch (error) {
+    console.error("widget_copy_translation_failed", targetLanguage, error.message);
+    return null;
+  }
+}
+
+function parseJsonBlock(value) {
+  const text = String(value || "").trim().replace(/^```(?:json)?/i, "").replace(/```$/, "").trim();
+  return JSON.parse(text);
+}
+
+function syncLegacyWidgetCopy(settings) {
+  for (const language of Object.keys(settings.widgetCopy || {})) {
+    const copy = settings.widgetCopy[language];
+    settings.title = { ...(settings.title || {}), [language]: copy.title };
+    settings.intro = { ...(settings.intro || {}), [language]: copy.intro };
+    settings.offlineIntro = { ...(settings.offlineIntro || {}), [language]: copy.offlineIntro };
+    settings.placeholder = { ...(settings.placeholder || {}), [language]: copy.placeholder };
+    settings.sendLabel = { ...(settings.sendLabel || {}), [language]: copy.sendLabel };
+  }
+}
+
+function languageFromUrl(value) {
+  try {
+    return allowedWidgetLanguage(new URL(value).pathname.split("/").filter(Boolean)[0]);
+  } catch {
+    return "";
+  }
+}
+
+function allowedWidgetLanguage(value) {
+  const language = normalizeLanguage(value);
+  return EUROPEAN_WIDGET_LANGUAGES.has(language) ? language : "";
+}
+
 function normalizeOpenAiApiKey(value) {
   const text = String(value || "").trim();
   if (!text || isMaskedApiKey(text)) return "";
@@ -1283,6 +1490,8 @@ function formatSite(site) {
   const settings = parseJson(site.settings_json, defaultSettings());
   settings.notifications = { ...defaultSettings().notifications, ...(settings.notifications || {}) };
   settings.launcherEffects = { ...defaultSettings().launcherEffects, ...(settings.launcherEffects || {}) };
+  settings.widgetLanguage = normalizeWidgetLanguageSettings(settings.widgetLanguage);
+  settings.widgetCopy = normalizeWidgetCopy(settings.widgetCopy || {}, settings);
   settings.translations = { ...defaultSettings().translations, ...(settings.translations || {}) };
   const storedOpenAiKey = settings.translations.openaiApiKey || OPENAI_API_KEY;
   settings.translations.hasOpenaiApiKey = Boolean(storedOpenAiKey);
@@ -1302,7 +1511,6 @@ function snippetFor(site) {
   return `<script>
   window.MaalFlows = {
     siteKey: "${site.site_key}",
-    lang: "cs",
     apiBase: "${PUBLIC_BASE_URL}"
   };
 </script>
@@ -1313,6 +1521,10 @@ function getDefaultSite() {
   return db.prepare("SELECT * FROM sites ORDER BY id LIMIT 1").get();
 }
 
+function getSiteById(id) {
+  return db.prepare("SELECT * FROM sites WHERE id = ?").get(id);
+}
+
 function findConversation(publicId) {
   return db.prepare(`
     SELECT c.*, s.site_key, vp.display_name AS visitor_display_name,