fix: normalize detected locale aliases #96

Author: dreamguxiang

frontend/src/utils/i18nUtils.ts

@@ -4,11 +4,36 @@
  */
 export const normalizeLanguage = (lng: string): string => {
   if (!lng) return "en_US";
-  const lower = lng.toLowerCase();
-  if (lower === "en-us" || lower === "en") return "en_US";
-  if (lower === "zh-cn" || lower === "zh") return "zh_CN";
-  if (lower === "ja-jp" || lower === "ja") return "ja_JP";
-  if (lower === "ru-ru" || lower === "ru") return "ru_RU";
-  if (lower === "zh-hk" || lower === "zhhk") return "zh_HK";
-  return lng;
+  const normalized = lng.trim().replace(/_/g, "-").toLowerCase();
+  const aliases: Record<string, string> = {
+    en: "en_US",
+    "en-us": "en_US",
+    zh: "zh_CN",
+    "zh-cn": "zh_CN",
+    "zh-hans": "zh_CN",
+    "zh-hans-cn": "zh_CN",
+    zhhk: "zh_HK",
+    "zh-hk": "zh_HK",
+    "zh-hant": "zh_HK",
+    "zh-hant-hk": "zh_HK",
+    "zh-tw": "zh_HK",
+    ja: "ja_JP",
+    "ja-jp": "ja_JP",
+    ru: "ru_RU",
+    "ru-ru": "ru_RU",
+    ko: "ko_KR",
+    "ko-kr": "ko_KR",
+    fr: "fr_FR",
+    "fr-fr": "fr_FR",
+    de: "de_DE",
+    "de-de": "de_DE",
+    es: "es_ES",
+    "es-es": "es_ES",
+    pt: "pt_PT",
+    "pt-pt": "pt_PT",
+    it: "it_IT",
+    "it-it": "it_IT",
+  };
+
+  return aliases[normalized] || aliases[normalized.split("-")[0]] || "en_US";
 };