Resolve the language setting persistence issue

- Move i18n initialization to async function
- Sync i18n with settings store language
- Add Root component for i18n loading state
- Convert i18n.js to TypeScript

lightrag_webui/src/components/Root.tsx

@@ -0,0 +1,24 @@
+import { StrictMode, useEffect, useState } from 'react'
+import { initializeI18n } from '@/i18n'
+import App from '@/App'
+
+export const Root = () => {
+  const [isI18nInitialized, setIsI18nInitialized] = useState(false)
+
+  useEffect(() => {
+    // Initialize i18n immediately with persisted language
+    initializeI18n().then(() => {
+      setIsI18nInitialized(true)
+    })
+  }, [])
+
+  if (!isI18nInitialized) {
+    return null // or a loading spinner
+  }
+
+  return (
+    <StrictMode>
+      <App />
+    </StrictMode>
+  )
+}

lightrag_webui/src/i18n.js

@@ -1,21 +0,0 @@
-import i18n from 'i18next';
-import { initReactI18next } from 'react-i18next';
-
-import en from './locales/en.json';
-import zh from './locales/zh.json';
-
-i18n
-  .use(initReactI18next)
-  .init({
-    resources: {
-      en: { translation: en },
-      zh: { translation: zh }
-    },
-    lng: 'en', // default
-    fallbackLng: 'en',
-    interpolation: {
-      escapeValue: false
-    }
-  });
-
-export default i18n;

lightrag_webui/src/i18n.ts

@@ -0,0 +1,37 @@
+import i18n from 'i18next'
+import { initReactI18next } from 'react-i18next'
+import { useSettingsStore } from '@/stores/settings'
+
+import en from './locales/en.json'
+import zh from './locales/zh.json'
+
+// Function to sync i18n with store state
+export const initializeI18n = async (): Promise<typeof i18n> => {
+  // Get initial language from store
+  const initialLanguage = useSettingsStore.getState().language
+
+  // Initialize with store language
+  await i18n.use(initReactI18next).init({
+    resources: {
+      en: { translation: en },
+      zh: { translation: zh }
+    },
+    lng: initialLanguage,
+    fallbackLng: 'en',
+    interpolation: {
+      escapeValue: false
+    }
+  })
+
+  // Subscribe to language changes
+  useSettingsStore.subscribe((state) => {
+    const currentLanguage = state.language
+    if (i18n.language !== currentLanguage) {
+      i18n.changeLanguage(currentLanguage)
+    }
+  })
+
+  return i18n
+}
+
+export default i18n

lightrag_webui/src/main.tsx

@@ -1,12 +1,5 @@
-import { StrictMode } from 'react'
 import { createRoot } from 'react-dom/client'
 import './index.css'
-import App from './App.tsx'
-import "./i18n";
+import { Root } from '@/components/Root'
 
-
-createRoot(document.getElementById('root')!).render(
-  <StrictMode>
-    <App />
-  </StrictMode>
-)
+createRoot(document.getElementById('root')!).render(<Root />)

lightrag_webui/src/stores/settings.ts

@@ -59,11 +59,27 @@ interface SettingsState {
   setCurrentTab: (tab: Tab) => void
 }
 
+// Helper to get initial state from localStorage
+const getInitialState = () => {
+  try {
+    const stored = localStorage.getItem('settings-storage')
+    if (stored) {
+      const { state } = JSON.parse(stored)
+      return {
+        theme: state?.theme || 'system',
+        language: state?.language || 'zh'
+      }
+    }
+  } catch (e) {
+    console.error('Failed to parse settings from localStorage:', e)
+  }
+  return { theme: 'system', language: 'zh' }
+}
+
 const useSettingsStoreBase = create<SettingsState>()(
   persist(
     (set) => ({
-      theme: 'system',
-      language: 'zh',
+      ...getInitialState(),
       refreshLayout: () => {
         const graphState = useGraphStore.getState();
         const currentGraph = graphState.sigmaGraph;
@@ -116,10 +132,13 @@ const useSettingsStoreBase = create<SettingsState>()(
       setTheme: (theme: Theme) => set({ theme }),
 
       setLanguage: (language: Language) => {
+        set({ language })
+        // Update i18n after state is updated
         import('i18next').then(({ default: i18n }) => {
-          i18n.changeLanguage(language);
-        });
-        set({ language });
+          if (i18n.language !== language) {
+            i18n.changeLanguage(language)
+          }
+        })
       },
 
       setGraphLayoutMaxIterations: (iterations: number) =>