import { createContext, useContext, useEffect, useMemo, useState, useCallback } from 'react';
import { api, setUnauthorizedHandler } from '../services/api.js';

const AuthContext = createContext(null);

export function AuthProvider({ children }) {
  const [user, setUser] = useState(null);
  const [ready, setReady] = useState(false);

  const logout = useCallback(() => {
    api.setToken(null);
    setUser(null);
  }, []);

  useEffect(() => {
    setUnauthorizedHandler(() => logout());
  }, [logout]);

  useEffect(() => {
    const token = localStorage.getItem('plc_token');
    if (!token) { setReady(true); return; }
    api.get('/auth/me')
      .then((me) => setUser(me))
      .catch(() => logout())
      .finally(() => setReady(true));
  }, [logout]);

  const login = useCallback(async (email, password) => {
    const result = await api.post('/auth/login', { email, password });
    api.setToken(result.token);
    setUser(result.user);
    return result.user;
  }, []);

  const value = useMemo(() => ({ user, ready, login, logout }), [user, ready, login, logout]);

  return <AuthContext.Provider value={value}>{children}</AuthContext.Provider>;
}

export function useAuth() {
  const ctx = useContext(AuthContext);
  if (!ctx) throw new Error('useAuth debe usarse dentro de AuthProvider');
  return ctx;
}