import React, { useState, useEffect } from 'react';
import { Routes, Route, useNavigate, useLocation, Navigate } from 'react-router-dom';
import Sidebar, { PageId } from './components/Sidebar';
import Navbar from './components/Navbar';
import Home from './pages/Home';
import ModelSquare from './pages/ModelSquare';
import Profile from './pages/Profile';
import Login from './pages/Login';
import Register from './pages/Register';
import OpenPlatform from './pages/OpenPlatform';
import UserAgreement from './pages/UserAgreement';
import PrivacyPolicy from './pages/PrivacyPolicy';
import SSOCallback from './pages/SSOCallback';
import ModelPricingDetail from './pages/ModelPricingDetail';
import { authService } from './services/authService';
import { Loader2 } from './icons/commonIcons';
import { NotificationProvider } from './contexts/NotificationContext';
import './styles/markdown.css';

const API_BASE = import.meta.env.VITE_API_BASE_URL ?? 'http://localhost:8010';

// 品牌配置 Context
export interface BrandingConfig { system_name: string; system_logo: string; icp_number: string }
export const BrandingContext = React.createContext<BrandingConfig>({ system_name: '四川路桥Maas算力平台', system_logo: '', icp_number: '' })

const pagePathMap: Record<PageId, string> = {
  home: '/',
  models: '/models',
  platform: '/platform',
  profile: '/profile',
};

// 公开路由（不需要登录）
const publicRoutes = ['/login', '/register', '/sso-callback', '/auth/callback', '/user-agreement', '/privacy-policy'];

// 认证状态检查组件
const AuthGuard: React.FC<{ children: React.ReactNode }> = ({ children }) => {
  const location = useLocation();
  const [isChecking, setIsChecking] = useState(true);
  const [isAuthenticated, setIsAuthenticated] = useState(false);

  useEffect(() => {
    const checkAuth = async () => {
      if (publicRoutes.includes(location.pathname)) {
        setIsChecking(false);
        return;
      }

      if (!authService.isAuthenticated()) {
        setIsAuthenticated(false);
        setIsChecking(false);
        return;
      }

      try {
        const isValid = await authService.checkAndRefreshToken();
        setIsAuthenticated(isValid);
      } catch (error) {
        console.error('[AuthGuard] Auth check failed:', error);
        setIsAuthenticated(false);
      } finally {
        setIsChecking(false);
      }
    };

    checkAuth();
  }, [location.pathname]);

  // 订阅认证状态变化
  useEffect(() => {
    const unsubscribe = authService.subscribe(() => {
      const authenticated = authService.isAuthenticated();
      setIsAuthenticated(authenticated);
    });

    return () => unsubscribe();
  }, []);

  // 正在检查认证状态
  if (isChecking && !publicRoutes.includes(location.pathname)) {
    return (
      <div className="min-h-screen bg-gray-50 flex items-center justify-center">
        <div className="flex flex-col items-center gap-4">
          <Loader2 className="w-8 h-8 text-blue-600 animate-spin" />
          <span className="text-gray-600">验证登录状态...</span>
        </div>
      </div>
    );
  }

  // 未登录且不是公开路由 → 一律跳登录页（登录页上有 SSO 按钮供用户选择）
  if (!isAuthenticated && !publicRoutes.includes(location.pathname)) {
    return <Navigate to="/login" state={{ from: location }} replace />;
  }

  // 已登录且访问登录/注册页，重定向到首页
  if (isAuthenticated && (location.pathname === '/login' || location.pathname === '/register')) {
    return <Navigate to="/" replace />;
  }

  return <>{children}</>;
};

// 主布局（带侧边栏和导航栏）
const MainLayout: React.FC<{ children: React.ReactNode }> = ({ children }) => {
  const location = useLocation();
  const branding = React.useContext(BrandingContext);

  return (
    <div className="min-h-screen flex flex-col bg-gray-50">
      <Navbar />
      <div className="flex flex-1 pt-14 sm:pt-16">
        <Sidebar />
        <main className="flex-1 ml-0 md:ml-[11rem] h-[calc(100vh-3.5rem)] sm:h-[calc(100vh-4rem)] flex flex-col overflow-y-auto pb-14 md:pb-0">
          <div className="max-w-[1800px] mx-auto px-3 sm:px-4 md:px-2 py-2 w-full flex-1 flex flex-col min-h-0">
            {children}
            {location.pathname === '/' && (
              <footer className="mt-6 px-2 border-t border-gray-100 text-center py-2 flex flex-col items-center gap-1">
                <p className="text-xs text-gray-400">© 2026 {branding.system_name}</p>
                <div className="flex items-center justify-center gap-4 text-xs text-gray-400">
                  <a
                    href="https://beian.mps.gov.cn/#/query/webSearch?code=51019002009294"
                    target="_blank"
                    rel="noopener noreferrer"
                    className="flex items-center gap-1 hover:text-gray-600"
                  >
                    <img src="https://beian.mps.gov.cn/web/assets/logo01.6189a29f.png" alt="公安备案图标" className="h-4 w-4" />
                    川公网安备51019002009294号
                  </a>
                  <a
                    href="https://beian.miit.gov.cn/"
                    target="_blank"
                    rel="noopener noreferrer"
                    className="hover:text-gray-600"
                  >
                    蜀ICP备2025168675号-3
                  </a>
                </div>
              </footer>
            )}
          </div>
        </main>
      </div>
    </div>
  );
};

// 认证布局（无侧边栏和导航栏，用于登录/注册页面）
const AuthLayout: React.FC<{ children: React.ReactNode }> = ({ children }) => {
  return <>{children}</>;
};

const App: React.FC = () => {
  const navigate = useNavigate();
  const location = useLocation();

  // 品牌配置
  const [branding, setBranding] = React.useState<BrandingConfig>({ system_name: '四川路桥Maas算力平台', system_logo: '', icp_number: '' });
  useEffect(() => {
    fetch(`${API_BASE}/api/public/branding`)
      .then(r => r.json())
      .then(d => {
        if (d.system_name) {
          setBranding(d);
          document.title = d.system_name;
        }
        // 动态更新 favicon
        if (d.system_logo) {
          let link = document.querySelector<HTMLLinkElement>("link[rel~='icon']");
          if (!link) {
            link = document.createElement('link');
            link.rel = 'icon';
            document.head.appendChild(link);
          }
          link.href = d.system_logo;
        }
      })
      .catch(() => {});
  }, []);

  // 判断是否是认证页面（登录/注册）
  const isAuthPage = publicRoutes.includes(location.pathname);

  return (
    <BrandingContext.Provider value={branding}>
    <NotificationProvider>
      <AuthGuard>
        {isAuthPage ? (
          <AuthLayout>
            <Routes>
              <Route path="/login" element={<Login />} />
              <Route path="/register" element={<Register />} />
              <Route path="/sso-callback" element={<SSOCallback />} />
              <Route path="/auth/callback" element={<SSOCallback />} />
              <Route path="/user-agreement" element={<UserAgreement />} />
              <Route path="/privacy-policy" element={<PrivacyPolicy />} />
            </Routes>
          </AuthLayout>
        ) : (
          <MainLayout>
            <Routes>
              <Route path="/" element={<Home />} />
              <Route path="/models" element={<ModelSquare />} />
              <Route path="/models/pricing/:modelCode" element={<ModelPricingDetail />} />
              <Route path="/profile" element={<Profile />} />
              <Route path="/platform" element={<OpenPlatform />} />
              <Route path="/user-agreement" element={<UserAgreement />} />
              <Route path="*" element={<Navigate to="/" replace />} />
            </Routes>
          </MainLayout>
        )}
      </AuthGuard>
    </NotificationProvider>
    </BrandingContext.Provider>
  );
};

export default App;