import React, { createContext, useContext, useEffect, useState } from 'react';
import api from '../api/client';
import type { User } from '../types';

interface AuthContextType {
  user: User | null;
  loading: boolean;
  login: (email: string, password: string) => Promise<void>;
  logout: () => Promise<void>;
}

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

export function AuthProvider({ children }: { children: React.ReactNode }) {
  const [user, setUser] = useState<User | null>(null);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    const token = localStorage.getItem('auth_token');
    if (!token) {
      setLoading(false);
      return;
    }
    api.get('/user')
      .then(r => setUser(r.data))
      .catch(() => localStorage.removeItem('auth_token'))
      .finally(() => setLoading(false));
  }, []);

  const login = async (email: string, password: string) => {
    const { data } = await api.post('/login', { email, password });
    localStorage.setItem('auth_token', data.token);
    setUser(data.user);
  };

  const logout = async () => {
    await api.post('/logout').catch(() => {});
    localStorage.removeItem('auth_token');
    setUser(null);
  };

  return (
    <AuthContext.Provider value={{ user, loading, login, logout }}>
      {children}
    </AuthContext.Provider>
  );
}

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