import type { H3Event } from "h3";
import { nextSessionId, readSessions, readSubscriptions, writeSessions, writeSubscriptions } from "~/server/database";
import { Session } from "~/shared/types/account";

async function removeSessionSubscription(sessionId: number) {
	const subscriptions = await readSubscriptions();
	const index = subscriptions.findIndex(subscription => subscription.sessionId === sessionId);
	if (index !== -1) {
		subscriptions.splice(index, 1);
		await writeSubscriptions(subscriptions);
	}
}

async function clearAccountSessionInternal(event: H3Event, sessions: Session[]) {
	const existingSessionCookie = await getSignedCookie(event, "session");
	if (existingSessionCookie) {
		const sessionId = parseInt(existingSessionCookie, 10);
		const sessionIndex = sessions.findIndex(session => session.id === sessionId);
		if (sessionIndex !== -1) {
			sessions.splice(sessionIndex, 1);
			await removeSessionSubscription(sessionId);
			return true;
		}
	}
	return false;
}

export async function clearAccountSession(event: H3Event) {
	const sessions = await readSessions();
	if (await clearAccountSessionInternal(event, sessions)) {
		await writeSessions(sessions);
	}
	setCookie(event, "session", "")
}

export async function setAccountSession(event: H3Event, accountId: number) {
	const sessions = await readSessions();
	await clearAccountSessionInternal(event, sessions);

	const newSession: Session = {
		accountId,
		id: await nextSessionId(),
	};

	sessions.push(newSession);
	await writeSessions(sessions);
	await setSignedCookie(event, "session", String(newSession.id))
}

export async function getAccountSession(event: H3Event) {
	const sessionCookie = await getSignedCookie(event, "session");
	if (sessionCookie) {
		const sessionId = parseInt(sessionCookie, 10);
		const sessions = await readSessions();
		return sessions.find(session => session.id === sessionId);
	}
}

export async function requireAccountSession(event: H3Event) {
	const session = await getAccountSession(event);
	if (!session)
		throw createError({
			status: 401,
			message: "Account session required",
		});
	return session;
}