import { onAuthStateChanged, signOut, fetchSignInMethodsForEmail, signInWithPopup } from "firebase/auth";

import React, { useContext, useEffect, useState } from "react";

import { GithubAuthProvider, GoogleAuthProvider, auth } from "../components/firebase";

const AuthContext = React.createContext();

export function useAuth() {

return useContext(AuthContext);

}

export function AuthProvider({ children }) {

const [currentUser, setCurrentUser] = useState(null);

const googleSignIn = async () => {

const provider = new GoogleAuthProvider();

await signInWithPopup(auth, provider);

};

const githubSignIn = async () => {

const provider = new GithubAuthProvider();

try {

// Attempt to sign in with GitHub

const result = await signInWithPopup(auth, provider);

return result.user;

} catch (error) {

// Check if the error is for an existing account

if (error.code === "auth/account-exists-with-different-credential") {

const email = error.customData.email;

const signInMethods = await fetchSignInMethodsForEmail(auth, email);

if (signInMethods.includes("google.com")) {

// If the existing account is Google, sign in with Google instead

alert("You already have an account with this email using Google. Signing you in with Google now.");

const googleProvider = new GoogleAuthProvider();

const googleResult = await signInWithPopup(auth, googleProvider);

return googleResult.user;

} else {

alert("An account already exists with this email. Please sign in using one of the other method");

}

}

throw error;

}

};

function logOut() {

signOut(auth);

}

useEffect(() => {

const unsubscribe = onAuthStateChanged(auth, (user) => {

setCurrentUser(user);

});

return () => unsubscribe();

}, []);

return <AuthContext.Provider value={{ currentUser, googleSignIn, githubSignIn, logOut }}>{children}</AuthContext.Provider>;

}