import { STATUS_CODE, STATUS_TEXT, type StatusCode } from "jsr:@std/http";

const ALLOWED_ORIGIN = "http://0.0.0.0:8042";

const sessions = new Map<string, WebSocket>();

function createSession(socket: WebSocket): string {
	const session = crypto.randomUUID();
	sessions.set(session, socket);

	return session;
}

function createResponse(
	status: StatusCode,
	body: BodyInit | null = null,
): Response {
	return new Response(body, { status, statusText: STATUS_TEXT[status] });
}

export default function (request: Request): Response {
	if (request.headers.get("upgrade")?.toLowerCase() !== "websocket") {
		return createResponse(STATUS_CODE.UpgradeRequired);
	}

	const url = new URL(request.url);
	if (url.origin !== ALLOWED_ORIGIN) {
		return createResponse(STATUS_CODE.BadRequest);
	}

	const sessionId = url.searchParams.get("sessionId");

	if (sessionId === null) {
		const upgrade = Deno.upgradeWebSocket(request);
		createSession(upgrade.socket);

		return upgrade.response;
	} else {
		const session = sessions.get(sessionId);
		if (session === null) {
			return createResponse(STATUS_CODE.Unauthorized);
		}

		// TODO
		// I need a new socket every time
	}

	return createResponse(STATUS_CODE.InternalServerError);
}