import { useState, useEffect, useRef } from 'react';
import { useRouter } from 'next/router';
import { AppProps } from 'next/app';
import { Toaster } from 'react-hot-toast';
import { User } from '@supabase/supabase-js';
import useClientMount from '../utils/useClientMount';
import ErrorBoundary from '../components/ErrorBoundary';
import '../styles/globals.css';

// 自定义用户类型，用于 JWT 认证
interface CustomUser {
  id: string;
  email: string;
  name: string;
  userType: string;
  phone?: string;
  avatarUrl?: string;
}

export default function App({ Component, pageProps }: AppProps) {
  const [user, setUser] = useState<CustomUser | null>(null);
  const [loading, setLoading] = useState(true);
  const [navigationInProgress, setNavigationInProgress] = useState(false);
  const isClient = useClientMount();
  const router = useRouter();
  const navigationTimeoutRef = useRef<NodeJS.Timeout | null>(null);

  // 防抖路由跳转函数
  const navigateWithDebounce = (path: string) => {
    if (navigationInProgress) return;
    
    setNavigationInProgress(true);
    
    // 清除之前的定时器
    if (navigationTimeoutRef.current) {
      clearTimeout(navigationTimeoutRef.current);
    }
    
    // 设置新的定时器
    navigationTimeoutRef.current = setTimeout(() => {
      router.push(path).finally(() => {
        setNavigationInProgress(false);
      });
    }, 100); // 100ms 防抖延迟
  };

  // 检查 JWT 令牌的有效性
  const checkJWTAuth = async () => {
    try {
      const token = localStorage.getItem('adminToken');
      if (!token) {
        return null;
      }

      // 验证令牌
      const response = await fetch('/api/auth/verify-token', {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          'Authorization': `Bearer ${token}`
        }
      });

      if (response.ok) {
        const data = await response.json();
        return data.user;
      } else {
        // 令牌无效，清除本地存储
        localStorage.removeItem('adminToken');
        return null;
      }
    } catch (error) {
      console.error('Token verification error:', error);
      localStorage.removeItem('adminToken');
      return null;
    }
  };

  useEffect(() => {
    // 只在客户端执行
    if (!isClient) return;
    
    // 检查是否为演示模式
    const isDemoMode = !process.env.NEXT_PUBLIC_SUPABASE_URL || 
                      process.env.NEXT_PUBLIC_SUPABASE_URL === 'https://demo.supabase.co' ||
                      process.env.NEXT_PUBLIC_SUPABASE_URL === '';

    const checkUser = async () => {
      try {
        // 使用自定义 JWT 认证检查
        const jwtUser = await checkJWTAuth();
        
        if (jwtUser) {
          setUser(jwtUser);
          // 如果当前在登录页面且已经认证，重定向到仪表板
          if (router.pathname === '/auth/login') {
            navigateWithDebounce('/dashboard');
          }
        } else {
          setUser(null);
          // 如果在需要认证的页面但未登录，重定向到登录页
          const protectedRoutes = ['/dashboard', '/admin', '/settings'];
          const isProtectedRoute = protectedRoutes.some(route => 
            router.pathname.startsWith(route)
          );
          
          if (isProtectedRoute) {
            navigateWithDebounce('/auth/login');
          }
        }
      } catch (error) {
        console.error('Auth check error:', error);
        setUser(null);
      } finally {
        setLoading(false);
      }
    };

    checkUser();

    // 监听路由变化，重新检查认证状态
    const handleRouteChange = () => {
      checkUser();
    };

    router.events.on('routeChangeComplete', handleRouteChange);

    return () => {
      router.events.off('routeChangeComplete', handleRouteChange);
      // 清理定时器
      if (navigationTimeoutRef.current) {
        clearTimeout(navigationTimeoutRef.current);
      }
    };
  }, [router, isClient]);

  // 在客户端挂载之前，显示最小化的 loading 状态以避免水合错误
  if (!isClient) {
    return (
      <div className="min-h-screen flex items-center justify-center bg-gray-50" suppressHydrationWarning>
        <div className="loading-spinner"></div>
      </div>
    );
  }

  // 显示加载状态
  if (loading) {
    return (
      <div className="min-h-screen flex items-center justify-center bg-gray-50">
        <div className="loading-spinner"></div>
      </div>
    );
  }

  return (
    <ErrorBoundary>
      <div suppressHydrationWarning>
        <Component {...pageProps} user={user} />
        <Toaster
          position="top-right"
          toastOptions={{
            duration: 4000,
            style: {
              background: '#363636',
              color: '#fff',
            },
            success: {
              duration: 3000,
              iconTheme: {
                primary: '#10b981',
                secondary: '#fff',
              },
            },
            error: {
              duration: 5000,
              iconTheme: {
                primary: '#ef4444',
                secondary: '#fff',
              },
            },
          }}
        />
      </div>
    </ErrorBoundary>
  );
}