import {
    signInWithEmailAndPassword,
    createUserWithEmailAndPassword,
    sendEmailVerification,
    type Auth,
} from "firebase/auth";
import { setDoc } from "firelordjs";
import { UserRef } from "$lib/firebase/refs";
import { AvatarMode } from "$lib/firebase/enums";
import type { FirebaseError } from "firebase/app";

export const authHandler = async (auth: Auth, event: SubmitEvent): Promise<FirebaseError | null> => {
    const buttonType: HTMLButtonElement = (event.submitter as HTMLButtonElement);
    const form: HTMLFormElement = (event.target as HTMLFormElement);

    if (buttonType.value === "Login") {
        return login(auth, form);
    } else if (buttonType.value === "Register") {
        return register(auth, form);
    } else {
        console.log("Invalid button type");
        return null;
    }
};

const login = async (auth: Auth, form: HTMLFormElement): Promise<FirebaseError | null> => {
    const email: string = form.email.value;
    const password: string = form.password.value;

    try {
        await signInWithEmailAndPassword(auth, email, password);
        return null;
    } catch (error: unknown) {
        return error as FirebaseError;
    }
}

const register = async (auth: Auth, form: HTMLFormElement): Promise<FirebaseError | null> => {
    const email: string = form.email.value;
    const password: string = form.password.value;

    try {
        await createUserWithEmailAndPassword(auth, email, password);
        if (auth.currentUser !== null) {
            await sendEmailVerification(auth.currentUser);
            await setDoc(UserRef.doc(auth.currentUser.uid), {
                avatarMode: AvatarMode.Gravatar,
            });
        }
        return null;
    } catch (error: unknown) {
        return error as FirebaseError;
    }
}