import type { BetterAuthClientOptions, InferSessionFromClient, InferUserFromClient } from 'better-auth/client';
import { authClient } from '~~/lib/auth-client';

export const useAuth = () => {
    const session = useState<InferSessionFromClient<BetterAuthClientOptions> | null>('auth:session', () => null);
    const user = useState<InferUserFromClient<BetterAuthClientOptions> | null>('auth:user', () => null);
    const sessionFetching = import.meta.server ? ref(false) : useState('auth:sessionFetching', () => false);

    const fetchSession = async () => {
        if (sessionFetching.value) {
            console.log('already fetching session');
            return;
        }
        sessionFetching.value = true;
        let data: {
            session: InferSessionFromClient<BetterAuthClientOptions>;
            user: InferUserFromClient<BetterAuthClientOptions>;
        } | null = null;
        if (import.meta.server) {
            data =
                (
                    await useFetch<{
                        session: InferSessionFromClient<BetterAuthClientOptions>;
                        user: InferUserFromClient<BetterAuthClientOptions>;
                    }>('/api/auth/get-session')
                ).data.value ?? null;
        } else {
            data = (await authClient.getSession()).data;
        }
        session.value = data?.session || null;
        user.value = data?.user || null;
        sessionFetching.value = false;
        return data;
    };

    if (import.meta.client) {
        authClient.$store.listen('$sessionSignal', async (signal) => {
            if (!signal) return;
            await fetchSession();

            if (!session.value) return;

            const triplit = useTriplitClient();
            if ('updateOptions' in triplit) {
                triplit.updateOptions({
                    token: session.value.token,
                });
            }
        });
    }

    return {
        session,
        user,
        loggedIn: computed(() => !!session.value),
        signIn: authClient.signIn,
        signUp: authClient.signUp,
        async signOut() {
            await authClient.signOut();
            session.value = null;
            user.value = null;
            return navigateTo('/auth/login');
        },
        fetchSession,
    };
};