import { Session, getSessionFromStorage } from '@inrupt/solid-client-authn-node';
import { redirect, type Handle } from '@sveltejs/kit';

export const handle: Handle = async ({ event, resolve }) => {
	const pathname = event.url.pathname;

	if (pathname.match(/^\/solid\/login\/?$/)) {
		const session = new Session({ keepAlive: true });
		event.cookies.set('sessionId', session.info.sessionId, { path: '/' });
		const oidcIssuer = event.url.searchParams.get('oidcIssuer');
		if (!oidcIssuer) throw new Error('No OIDC issuer provided');
		return await session.login({
			oidcIssuer,
			redirectUrl: `http://localhost:5173/solid/login/callback/`,
			clientName: 'Tabemono',
			handleRedirect: (url) => redirect(307, url)
		});
	}

	if (pathname === '/solid/login/callback/') {
		const sessionId = event.cookies.get('sessionId');
		if (!sessionId) throw new Error('No session ID');
		const session = await getSessionFromStorage(sessionId);
		const url = `${event.url.origin}/solid/login/callback/${event.url.search}`;
		if (session) {
			const res = await session.handleIncomingRedirect(url);
			if (res?.isLoggedIn) return redirect(307, '/');
			throw new Error('LOGIN ERROR');
		}
	}

	if (pathname === '/solid/logout') {
		const sessionId = event.cookies.get('sessionId');
		if (!sessionId) throw new Error('No session ID');
		const session = await getSessionFromStorage(sessionId);
		session?.logout();
		event.cookies.delete('sessionId', { path: '/' });
		return redirect(307, '/exit');
	}

	if (pathname === '/solid/fetch') {
		const resourceUrl = event.url.searchParams.get('resource');
		if (!resourceUrl) throw new Error('No resource URL provided');
		const sessionId = event.cookies.get('sessionId');
		if (!sessionId) throw new Error('No session ID');
		const session = await getSessionFromStorage(sessionId);
		return session?.fetch(resourceUrl);
	}

	// Provide session helper to event.locals
	event.locals.getSession = async () => {
		const sessionId = event.cookies.get('sessionId');
		if (sessionId) return await getSessionFromStorage(sessionId);
		return undefined;
	};

	const response = await resolve(event);
	return response;
};

export default handle;