Refactor server stuff

server/ref/deno.test.ts

@@ -0,0 +1,64 @@
+/// <reference lib="deno.ns" />
+import { assertEquals } from "jsr:@std/assert";
+import { close, connect, flush, href, setup } from "../testSetup.ts";
+import { getHandler } from "./deno.ts";
+
+Deno.test(
+	"Welcome all clients on connect.",
+	setup(async () => {
+		const [s1, m1] = await connect(href);
+		const [s2, m2] = await connect(href);
+
+		await flush();
+
+		assertEquals(m1, ["Welcome 1, type /join <room>."]);
+		assertEquals(m2, ["Welcome 2, type /join <room>."]);
+
+		await close(s2);
+		await close(s1);
+	}, getHandler()),
+);
+
+Deno.test(
+	"Messages all clients in a room on joining.",
+	setup(async () => {
+		const [s1, m1] = await connect(href);
+		const [s2, m2] = await connect(href);
+
+		await flush();
+		m1.length = 0;
+		m2.length = 0;
+
+		s1.send("/join meh");
+		s2.send("/join meh");
+		await flush();
+
+		assertEquals(m1, ["1 has joined!", "2 has joined!"]);
+		assertEquals(m2, ["2 has joined!"]);
+
+		await close(s2);
+		await close(s1);
+	}, getHandler()),
+);
+
+Deno.test(
+	"Messages remaining members if one left the room.",
+	setup(async () => {
+		const [s1, m1] = await connect(href);
+		const [s2, m2] = await connect(href);
+
+		s1.send("/join meh");
+		s2.send("/join meh");
+		await flush();
+
+		m1.length = 0;
+		m2.length = 0;
+		await close(s2);
+		await flush();
+
+		assertEquals(m1, ["2 has left!"]);
+		assertEquals(m2, []);
+
+		await close(s1);
+	}, getHandler()),
+);

server/ref/deno.ts

@@ -0,0 +1,80 @@
+/// <reference lib="deno.ns" />
+
+export function getHandler(): Deno.ServeHandler {
+	let nextId = 1;
+
+	const clientsMap = new Map<number, WebSocket>();
+	const clientRoomMap = new Map<number, string>();
+	const roomsMap = new Map<string, number[]>();
+
+	const broadcast = (room: string, message: string): void => {
+		const members = roomsMap.get(room)!;
+
+		for (const member of members) {
+			const socket = clientsMap.get(member);
+			if (socket && socket.readyState === WebSocket.OPEN) {
+				socket.send(message);
+			}
+		}
+	};
+
+	const commands = {
+		join: (id: number, args: string[]) => {
+			const room = args[0];
+			if (roomsMap.has(room)) {
+				roomsMap.get(room)!.push(id);
+			} else {
+				roomsMap.set(room, [id]);
+			}
+
+			clientRoomMap.getOrInsert(id, room); // not sure about that
+			broadcast(room, `${id} has joined!`);
+		},
+	} as const;
+
+	const handleConnection = (socket: WebSocket): void => {
+		const id = nextId++;
+
+		socket.onopen = () => {
+			clientsMap.set(id, socket);
+			socket.send(`Welcome ${id}, type /join <room>.`);
+		};
+
+		socket.onclose = () => {
+			const room = clientRoomMap.get(id);
+			if (room) {
+				clientRoomMap.delete(id);
+				const members = roomsMap.get(room)!;
+				members.splice(members.indexOf(id), 1);
+				broadcast(room, `${id} has left!`);
+			}
+			clientsMap.delete(id);
+		};
+
+		socket.onmessage = (message: MessageEvent) => {
+			const text = String(message.data);
+			if (text.startsWith("/")) {
+				const [command, ...args] = text.substring(1).split(" ");
+				try {
+					// @ts-ignore
+					commands[command](id, args);
+				} catch (error) {
+					socket.send(JSON.stringify(error));
+				}
+			}
+		};
+
+		socket.onerror = console.error;
+	};
+
+	return (request) => {
+		if (request.headers.get("upgrade") !== "websocket") {
+			return new Response("Upgrade Required", { status: 426 });
+		}
+
+		const { socket, response } = Deno.upgradeWebSocket(request);
+		handleConnection(socket);
+
+		return response;
+	};
+}