fix(splash): prevent login flicker on startup

src/App.tsx

@@ -17,18 +17,24 @@ import { MainLayout } from '@/components/layout/MainLayout';
 import { ProtectedRoute } from '@/router/ProtectedRoute';
 import { useAuthStore, useLanguageStore, useThemeStore } from '@/stores';
 
+const SPLASH_DURATION = 1500;
+const SPLASH_FADE_DURATION = 400;
+
 function App() {
   const initializeTheme = useThemeStore((state) => state.initializeTheme);
   const language = useLanguageStore((state) => state.language);
   const setLanguage = useLanguageStore((state) => state.setLanguage);
   const restoreSession = useAuthStore((state) => state.restoreSession);
-  const isAuthenticated = useAuthStore((state) => state.isAuthenticated);
 
+  const [splashReadyToFade, setSplashReadyToFade] = useState(false);
   const [showSplash, setShowSplash] = useState(true);
+  const [authReady, setAuthReady] = useState(false);
 
   useEffect(() => {
     initializeTheme();
-    restoreSession();
+    void restoreSession().finally(() => {
+      setAuthReady(true);
+    });
   }, [initializeTheme, restoreSession]);
 
   useEffect(() => {
@@ -36,13 +42,25 @@ function App() {
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, []); // 仅用于首屏同步 i18n 语言
 
+  useEffect(() => {
+    const timer = setTimeout(() => {
+      setSplashReadyToFade(true);
+    }, SPLASH_DURATION - SPLASH_FADE_DURATION);
+
+    return () => clearTimeout(timer);
+  }, []);
+
   const handleSplashFinish = useCallback(() => {
     setShowSplash(false);
   }, []);
 
-  // 仅在已认证时显示闪屏
-  if (showSplash && isAuthenticated) {
-    return <SplashScreen onFinish={handleSplashFinish} duration={1500} />;
+  if (showSplash) {
+    return (
+      <SplashScreen
+        fadeOut={splashReadyToFade && authReady}
+        onFinish={handleSplashFinish}
+      />
+    );
   }
 
   return (

src/components/common/SplashScreen.tsx

@@ -1,29 +1,25 @@
-import { useEffect, useState } from 'react';
+import { useEffect } from 'react';
 import { INLINE_LOGO_JPEG } from '@/assets/logoInline';
 import './SplashScreen.scss';
 
 interface SplashScreenProps {
   onFinish: () => void;
-  duration?: number;
+  fadeOut?: boolean;
 }
 
-export function SplashScreen({ onFinish, duration = 1500 }: SplashScreenProps) {
-  const [fadeOut, setFadeOut] = useState(false);
+const FADE_OUT_DURATION = 400;
 
+export function SplashScreen({ onFinish, fadeOut = false }: SplashScreenProps) {
   useEffect(() => {
-    const fadeTimer = setTimeout(() => {
-      setFadeOut(true);
-    }, duration - 400);
-
+    if (!fadeOut) return;
     const finishTimer = setTimeout(() => {
       onFinish();
-    }, duration);
+    }, FADE_OUT_DURATION);
 
     return () => {
-      clearTimeout(fadeTimer);
       clearTimeout(finishTimer);
     };
-  }, [duration, onFinish]);
+  }, [fadeOut, onFinish]);
 
   return (
     <div className={`splash-screen ${fadeOut ? 'fade-out' : ''}`}>

src/pages/LoginPage.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useMemo, useState } from 'react';
-import { useNavigate, useLocation } from 'react-router-dom';
+import { Navigate, useNavigate, useLocation } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
 import { Button } from '@/components/ui/Button';
 import { Input } from '@/components/ui/Input';
@@ -44,12 +44,10 @@ export function LoginPage() {
     init();
   }, [detectedBase, restoreSession, storedBase, storedKey]);
 
-  useEffect(() => {
-    if (isAuthenticated) {
-      const redirect = (location.state as any)?.from?.pathname || '/';
-      navigate(redirect, { replace: true });
-    }
-  }, [isAuthenticated, navigate, location.state]);
+  if (isAuthenticated) {
+    const redirect = (location.state as any)?.from?.pathname || '/';
+    return <Navigate to={redirect} replace />;
+  }
 
   const handleUseCurrent = () => {
     setApiBase(detectedBase);