import { createContext, useContext, useState, useEffect } from 'react';
import { supabase } from '../lib/supabase';

const AuthContext = createContext(null);

const PROFILE_CACHE_KEY = 'fourge_profile';

export function AuthProvider({ children }) {
  const [currentUser, setCurrentUser] = useState(() => {
    // Seed from cache instantly — no loading flash for returning users
    try {
      const cached = localStorage.getItem(PROFILE_CACHE_KEY);
      return cached ? JSON.parse(cached) : null;
    } catch { return null; }
  });
  const [loading, setLoading] = useState(true);

  const fetchAndCacheProfile = async (authUser) => {
    const { data } = await supabase
      .from('profiles')
      .select('*, company:companies(id, name, phone, address)')
      .eq('id', authUser.id)
      .single();
    if (data) {
      const profile = { ...data, email: authUser.email };
      setCurrentUser(profile);
      localStorage.setItem(PROFILE_CACHE_KEY, JSON.stringify(profile));
    }
  };

  useEffect(() => {
    // Fallback — stop blocking after 2s max
    const timeout = setTimeout(() => setLoading(false), 2000);
    let resolved = false;

    const { data: { subscription } } = supabase.auth.onAuthStateChange(async (event, session) => {
      if (session?.user) {
        // Fetch fresh profile in background (cache already seeded above)
        fetchAndCacheProfile(session.user);
      } else {
        setCurrentUser(null);
        localStorage.removeItem(PROFILE_CACHE_KEY);
      }

      if (!resolved) {
        resolved = true;
        clearTimeout(timeout);
        setLoading(false);
      }
    });

    return () => {
      clearTimeout(timeout);
      subscription.unsubscribe();
    };
  }, []);

  const login = async (email, password) => {
    const { error } = await supabase.auth.signInWithPassword({ email, password });
    if (error) return { error: error.message };
    return {};
  };

  const signup = async (email, password, name) => {
    const { error } = await supabase.auth.signUp({
      email,
      password,
      options: { data: { name, role: 'client' } },
    });
    if (error) return { error: error.message };
    const { error: loginError } = await supabase.auth.signInWithPassword({ email, password });
    if (loginError) return { error: loginError.message };
    return {};
  };

  const logout = async () => {
    await supabase.auth.signOut();
    setCurrentUser(null);
    localStorage.removeItem(PROFILE_CACHE_KEY);
  };

  if (loading) return (
    <div style={{
      minHeight: '100vh', background: '#111111',
      display: 'flex', alignItems: 'center', justifyContent: 'center',
    }}>
      <img src="/fourge-logo.png" alt="Fourge Branding" style={{ width: 160, opacity: 0.6 }} />
    </div>
  );

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

export const useAuth = () => useContext(AuthContext);