import { createContext, useContext, useState, useEffect, ReactNode } from 'react';
import { User, AuthState } from '../../types/auth';
import {
  getToken,
  getUser,
  saveToken,
  saveUser,
  clearAuth,
  isTokenExpired,
  refreshAuthToken,
  generateToken,
} from '../../lib/authStorage';

interface AuthContextType {
  authState: AuthState;
  login: (user: User) => void;
  logout: () => void;
  updateUser: (user: User) => void;
  checkAuth: () => boolean;
}

const AuthContext = createContext<AuthContextType | undefined>(undefined);

export function AuthProvider({ children }: { children: ReactNode }) {
  const [authState, setAuthState] = useState<AuthState>({
    isAuthenticated: false,
    user: null,
    token: null,
    refreshToken: null,
  });

  // 初始化时检查登录状态
  useEffect(() => {
    const initAuth = async () => {
      const token = getToken();
      const user = getUser();

      if (token && user) {
        // 检查token是否过期
        if (isTokenExpired()) {
          // 尝试刷新token
          const refreshed = await refreshAuthToken();
          if (refreshed) {
            setAuthState({
              isAuthenticated: true,
              user,
              token: refreshed.token,
              refreshToken: refreshed.refreshToken,
            });
          } else {
            // 刷新失败，自动使用默认账号登录
            await autoLoginWithDefaultAccount();
          }
        } else {
          setAuthState({
            isAuthenticated: true,
            user,
            token,
            refreshToken: getToken(),
          });
        }
      } else {
        // 没有登录信息，自动使用默认账号登录
        await autoLoginWithDefaultAccount();
      }
    };

    // 自动登录默认账号
    const autoLoginWithDefaultAccount = async () => {
      // 动态导入避免循环依赖
      const { validatePasswordLogin } = await import('../../lib/authStorage');
      
      // 使用默认管理员账号自动登录
      const result = await validatePasswordLogin('admin', 'admin123', 'AUTO');
      
      if (result.success && result.user) {
        const newToken = generateToken();
        const newRefreshToken = generateToken();
        
        saveToken(newToken, newRefreshToken);
        saveUser(result.user);
        
        setAuthState({
          isAuthenticated: true,
          user: result.user,
          token: newToken,
          refreshToken: newRefreshToken,
        });
      } else {
        // 自动登录失败，显示登录页面
        setAuthState({
          isAuthenticated: false,
          user: null,
          token: null,
          refreshToken: null,
        });
      }
    };

    initAuth();
  }, []);

  // 定期检查token有效性
  useEffect(() => {
    if (!authState.isAuthenticated) return;

    const interval = setInterval(async () => {
      if (isTokenExpired()) {
        const refreshed = await refreshAuthToken();
        if (refreshed) {
          setAuthState(prev => ({
            ...prev,
            token: refreshed.token,
            refreshToken: refreshed.refreshToken,
          }));
        } else {
          logout();
        }
      }
    }, 5 * 60 * 1000); // 每5分钟检查一次

    return () => clearInterval(interval);
  }, [authState.isAuthenticated]);

  const login = (user: User) => {
    const token = generateToken();
    const refreshToken = generateToken();

    saveToken(token, refreshToken);
    saveUser(user);

    setAuthState({
      isAuthenticated: true,
      user,
      token,
      refreshToken,
    });
  };

  const logout = () => {
    clearAuth();
    setAuthState({
      isAuthenticated: false,
      user: null,
      token: null,
      refreshToken: null,
    });
  };

  const updateUser = (user: User) => {
    saveUser(user);
    setAuthState(prev => ({
      ...prev,
      user,
    }));
  };

  const checkAuth = (): boolean => {
    return authState.isAuthenticated && !isTokenExpired();
  };

  return (
    <AuthContext.Provider value={{ authState, login, logout, updateUser, checkAuth }}>
      {children}
    </AuthContext.Provider>
  );
}

export function useAuth() {
  const context = useContext(AuthContext);
  if (context === undefined) {
    throw new Error('useAuth must be used within an AuthProvider');
  }
  return context;
}