'use client';

import React, {
  createContext,
  useContext,
  useState,
  useEffect,
  ReactNode,
} from 'react';
import { getAuth, createUserWithEmailAndPassword, signInWithEmailAndPassword, updateProfile, signOut } from 'firebase/auth';
import { app } from '@/lib/firebase';

interface User {
  uid: string;
  email: string | null;
  name: string | null;
}

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

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

interface AuthProviderProps {
  children: ReactNode;
}

export const AuthProvider = ({ children }: AuthProviderProps) => {
  const [user, setUser] = useState<User | null>(null);
  const [isLoading, setIsLoading] = useState(true);
  const auth = getAuth(app);

  useEffect(() => {
    // Listen to auth state changes
    const unsubscribe = auth.onAuthStateChanged((firebaseUser) => {
      if (firebaseUser) {
        setUser({
          uid: firebaseUser.uid,
          email: firebaseUser.email,
          name: firebaseUser.displayName,
        });
      } else {
        setUser(null);
      }
      setIsLoading(false);
    });

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

  const login = async (email: string, password: string) => {
    setIsLoading(true);
    try {
      await signInWithEmailAndPassword(auth, email, password);
    } catch (error: any) {
      setIsLoading(false);
      throw new Error(error.message || 'Login failed');
    }
  };

  const register = async (email: string, password: string, name: string) => {
    setIsLoading(true);
    try {
      const userCredential = await createUserWithEmailAndPassword(auth, email, password);
      await updateProfile(userCredential.user, { displayName: name });
      // User state will be updated by onAuthStateChanged listener
    } catch (error: any) {
      setIsLoading(false);
      throw new Error(error.message || 'Registration failed');
    }
  };

  const logout = async () => {
    await signOut(auth);
  };

  const value: AuthContextType = {
    user,
    isLoading,
    isAuthenticated: !!user,
    login,
    register,
    logout,
  };

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

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