Deno desktop stuff

.gitignore

@@ -2,3 +2,4 @@ build/
 world.json
 world.json.tmp
 server_mods/
+dist/

client/gui/title_screen.ts

@@ -20,8 +20,8 @@ const TITLE_SCALE = 8;
 // for the player when it fails
 export type JoinServer = (address: ServerAddress, name: string, status: (text: string) => void) => Promise<void>;
 
-// the first thing players see, like minecraft's title and multiplayer screens rolled into one:
-// a name, a server, and a button to join it
+// the first thing players see, like minecraft's title and multiplayer screens rolled into one: a name, a server,
+// and a button to join it. in the desktop app there's also singleplayer, which joins the app's own server
 export class TitleScreen extends GuiScreen {
 	#join_server: JoinServer;
 
@@ -33,6 +33,10 @@ export class TitleScreen extends GuiScreen {
 	);
 	server = new EditBox(WIDTH, ROW_HEIGHT, new TextInput(initial_server(), 256, (char) => char !== " "), "host:port");
 	join_button = new Button("Join server", WIDTH, ROW_HEIGHT, () => this.#join());
+	// the page was served by a game server of its own to play on alone, see desktop/main.ts
+	singleplayer_button = has_singleplayer()
+		? new Button("Singleplayer", WIDTH, ROW_HEIGHT, () => this.#join_singleplayer())
+		: undefined;
 	credits_button = new Button("Credits", WIDTH, ROW_HEIGHT, () => this.#open_credits());
 	// open over the title screen, it gets the input while it's there
 	#credits: CreditsScreen | undefined;
@@ -75,6 +79,7 @@ export class TitleScreen extends GuiScreen {
 		if (InputManager.is_key_pressed("Enter")) {
 			this.#join();
 		}
+		this.singleplayer_button?.handle_input();
 		this.join_button.handle_input();
 		this.credits_button.handle_input();
 	}
@@ -92,6 +97,7 @@ export class TitleScreen extends GuiScreen {
 		this.#label("Name", this.name);
 		this.#label("Server", this.server);
 		this.name.render();
+		this.singleplayer_button?.render();
 		this.server.render();
 		this.join_button.render();
 		this.credits_button.render();
@@ -121,12 +127,18 @@ export class TitleScreen extends GuiScreen {
 
 	#layout() {
 		const x = (canvas.width - WIDTH) / 2;
-		const total = 2 * (LABEL_GAP + ROW_HEIGHT + GAP) + 2 * ROW_HEIGHT + GAP;
+		const singleplayer_height = this.singleplayer_button ? ROW_HEIGHT + GAP : 0;
+		const total = 2 * (LABEL_GAP + ROW_HEIGHT + GAP) + singleplayer_height + 2 * ROW_HEIGHT + GAP;
 		let y = (canvas.height - total) / 2 + 40;
 		for (const field of [this.name, this.server]) {
 			field.x = x;
 			field.y = y + LABEL_GAP;
 			y += LABEL_GAP + ROW_HEIGHT + GAP;
+			if (field === this.name && this.singleplayer_button) {
+				this.singleplayer_button.x = x;
+				this.singleplayer_button.y = y;
+				y += singleplayer_height;
+			}
 		}
 		this.join_button.x = x;
 		this.join_button.y = y;
@@ -151,10 +163,21 @@ export class TitleScreen extends GuiScreen {
 			return;
 		}
 		remember(LAST_SERVER_KEY, this.server.value.trim());
-		remember(LAST_NAME_KEY, this.name.value);
+		await this.#connect(address);
+	}
 
+	// the server that served this page
+	async #join_singleplayer() {
+		if (this.#joining) {
+			return;
+		}
+		await this.#connect(server_address(location.host), "Starting singleplayer...");
+	}
+
+	async #connect(address: ServerAddress, status = `Connecting to ${address.base.host}...`) {
+		remember(LAST_NAME_KEY, this.name.value);
 		this.#set_joining(true);
-		this.status = `Connecting to ${address.base.host}...`;
+		this.status = status;
 		this.status_is_error = false;
 		try {
 			await this.#join_server(address, this.name.value, (text) => this.status = text);
@@ -167,6 +190,9 @@ export class TitleScreen extends GuiScreen {
 	#set_joining(joining: boolean) {
 		this.#joining = joining;
 		this.name.active = this.server.active = this.join_button.active = !joining;
+		if (this.singleplayer_button) {
+			this.singleplayer_button.active = !joining;
+		}
 	}
 
 	#show_error(message: string) {
@@ -202,8 +228,19 @@ function remember(key: string, value: string) {
 	}
 }
 
-// a server's mods can't be unloaded, so going back to the title screen starts the page over. without ?server=
-// or ?name=, so the fields show what was used last
-export function back_to_title() {
-	location.href = location.pathname;
+function has_singleplayer() {
+	return new URL(location.href).searchParams.has("singleplayer");
+}
+
+// a server's mods can't be unloaded, so going back to the title screen starts the page over. without ?server=
+// or ?name=, so the fields show what was used last. the desktop app keeps its ?singleplayer and ?server=, its saved
+// fields don't last between launches and the page's own address isn't a server to join
+export function back_to_title() {
+	const page = new URL(location.href);
+	const next = new URL(location.pathname, location.href);
+	if (has_singleplayer()) {
+		next.searchParams.set("server", page.searchParams.get("server") ?? "");
+		next.searchParams.set("singleplayer", "");
+	}
+	location.href = next.href;
 }

client/handshake.ts

@@ -25,12 +25,11 @@ export function default_server(page = new URL(location.href)): string {
 	return page.searchParams.get("server") ?? page.host;
 }
 
-// what a player typed as the server: host:port, or a full http(s) or ws(s) url
+// what a player typed as the server: host:port, or a full http(s) or ws(s) url to pick the scheme
 export function server_address(input: string, page = new URL(location.href)): ServerAddress {
 	const text = input.trim();
 	let host = text;
-	// without a scheme it's as secure as the page, browsers block insecure sockets from secure pages anyway
-	let secure = page.protocol === "https:";
+	let secure: boolean;
 	if (text.includes("://")) {
 		let url: URL;
 		try {
@@ -40,6 +39,10 @@ export function server_address(input: string, page = new URL(location.href)): Se
 		}
 		host = url.host;
 		secure = url.protocol === "https:" || url.protocol === "wss:";
+	} else {
+		// servers on this machine are plain ws and everything else is wss, whatever the page was served over. the
+		// desktop app's page is plain http on localhost, but the servers it joins are real domains behind tls
+		secure = !is_local_host(host);
 	}
 	if (!host || /[\s/?#]/.test(host)) {
 		throw new HandshakeError(`${text || "An empty address"} isn't a server address`);
@@ -52,6 +55,19 @@ export function server_address(input: string, page = new URL(location.href)): Se
 	};
 }
 
+const LOCAL_HOSTS = ["localhost", "127.0.0.1", "[::1]", "0.0.0.0"];
+
+// host is host:port, or just a host
+function is_local_host(host: string) {
+	let hostname: string;
+	try {
+		hostname = new URL(`http://${host}/`).hostname;
+	} catch {
+		return false;
+	}
+	return LOCAL_HOSTS.includes(hostname);
+}
+
 // a socket whose messages all land in one queue, so none get lost between the handshake and the game
 export class ServerSocket {
 	socket: WebSocket;

deno.json

@@ -5,17 +5,19 @@
 		"server": "deno run --unstable-worker-options --allow-net --allow-read --allow-write --allow-env server/main.ts",
 		"new-mod": "deno run --allow-read --allow-write tools/new_mod.ts",
 		"check-mods": "deno run --allow-read --allow-run tools/check_mods.ts",
-		"test": "deno test --allow-read --allow-write --allow-run tests/"
+		"test": "deno test --allow-read --allow-write --allow-run tests/",
+		"desktop": "deno run -A build.ts --once && deno desktop --allow-read --allow-write --allow-net --allow-env=BWORLD_SERVER,HOME,USERPROFILE,APPDATA,XDG_DATA_HOME --include build --include server_mods --include server/game/worker.ts --include desktop/config.json desktop/main.ts && deno run --allow-read --allow-write desktop/linux_launcher.ts dist/bworld"
 	},
 	"compilerOptions": {
 		"lib": ["dom", "dom.asynciterable", "dom.iterable", "deno.ns", "deno.unstable", "deno.webgpu"]
 	},
-	"unstable": ["bundle", "raw-imports"],
+	"unstable": ["bundle", "raw-imports", "worker-options"],
 	"fmt": {
 		"useTabs": true,
 		"indentWidth": 4,
 		"lineWidth": 120,
-		"newLineKind": "lf"
+		"newLineKind": "lf",
+		"exclude": ["desktop/*.md"]
 	},
 	"imports": {
 		"$/": "./",
@@ -30,5 +32,10 @@
 		"@std/path": "jsr:@std/path@^1.0.0",
 		"gl-matrix": "npm:gl-matrix@^3.4.4",
 		"marked": "npm:marked@^17.0.3"
+	},
+	"desktop": {
+		"app": { "name": "bworld", "identifier": "com.bworld.game" },
+		"backend": "cef",
+		"output": { "macos": "./dist/bworld.app", "windows": "./dist/bworld", "linux": "./dist/bworld" }
 	}
 }

desktop/config.json

@@ -0,0 +1,3 @@
+{
+	"server": "bworld.moder.fans"
+}

desktop/linux_launcher.ts

@@ -0,0 +1,45 @@
+// deno run --allow-read --allow-write desktop/linux_launcher.ts dist/bworld
+// deno desktop has no setting for chromium's command line, but its linux launcher passes its arguments on to chromium.
+// so this moves the launcher to bworld-bin and puts a script in its place that starts it with the switches webgpu
+// needs on some linux setups. run it on the app folder after deno desktop builds it; running it again does nothing
+const SWITCHES = [
+	"--enable-unsafe-webgpu",
+	"--ozone-platform=x11",
+	"--use-angle=vulkan",
+	"--enable-features=Vulkan,VulkanFromANGLE",
+];
+
+const dir = Deno.args[0];
+if (!dir) {
+	console.error("usage: linux_launcher.ts <app folder>, like dist/bworld");
+	Deno.exit(1);
+}
+const name = dir.replace(/\/+$/, "").split("/").pop()!;
+const launcher = `${dir}/${name}`;
+const binary = `${launcher}-bin`;
+
+// already wrapped: the launcher is a script now
+const head = new Uint8Array(4);
+const file = Deno.openSync(launcher);
+file.readSync(head);
+file.close();
+const is_elf = head[0] === 0x7f && head[1] === 0x45 && head[2] === 0x4c && head[3] === 0x46;
+if (!is_elf) {
+	console.log(`${launcher} is already wrapped`);
+	Deno.exit(0);
+}
+
+Deno.renameSync(launcher, binary);
+Deno.writeTextFileSync(
+	launcher,
+	`#!/bin/sh
+# starts ${name} with the chromium switches webgpu needs on some linux setups, see desktop/linux_launcher.ts.
+# BWORLD_CHROMIUM_FLAGS replaces them, set it to "" to start without any
+here="$(dirname "$(readlink -f "$0")")"
+# the binary finds its runtime by its own name, which is ${name}.so and not ${name}-bin.so
+export LAUFEY_RUNTIME_PATH="$here/${name}.so"
+exec "$here/${name}-bin" \${BWORLD_CHROMIUM_FLAGS-${SWITCHES.join(" ")}} "$@"
+`,
+);
+Deno.chmodSync(launcher, 0o755);
+console.log(`Wrapped ${launcher}: ${SWITCHES.join(" ")}`);

desktop/main.ts

@@ -0,0 +1,86 @@
+/// <reference lib="deno.desktop" />
+
+// the desktop app: the web client in a bundled chromium (deno desktop's cef backend), so people whose browser has no
+// webgpu (firefox) can still play. it joins servers like the browser does, and runs its own game server for
+// singleplayer, like minecraft java. build it with deno task desktop, see the desktop/ docs for how deno desktop works
+import { fromFileUrl, join } from "@std/path";
+import { type Host, serve_static, start_host } from "../server/host.ts";
+
+// where the project was built from: build/ and server_mods/ are bundled into the app with --include
+const ROOT = fromFileUrl(new URL("../", import.meta.url));
+const BUILD_DIR = join(ROOT, "build");
+
+// the server the address field starts with. "" leaves it empty for the player to fill in
+const config: { server?: string } = JSON.parse(
+	await Deno.readTextFile(new URL("./config.json", import.meta.url)),
+);
+const default_server = Deno.env.get("BWORLD_SERVER") ?? config.server ?? "";
+
+const win = new Deno.BrowserWindow({ title: "bworld", width: 1280, height: 720 });
+
+// the singleplayer game server, started the first time singleplayer connects so players who only join other servers
+// don't get a world made for them
+let host: Host | undefined;
+
+function singleplayer_host(): Host {
+	if (!host) {
+		const worlds = join(data_dir(), "worlds");
+		Deno.mkdirSync(worlds, { recursive: true });
+		host = start_host({
+			build_dir: BUILD_DIR,
+			server_mods_dir: join(ROOT, "server_mods"),
+			root: ROOT,
+			world_file: join(worlds, "world.json"),
+			on_fatal(message) {
+				console.error(message);
+				alert(`The singleplayer world stopped: ${message}`);
+				Deno.exit(1);
+			},
+		});
+	}
+	return host;
+}
+
+// the world gets saved before the app closes
+win.addEventListener("close", async (event) => {
+	if (!host) {
+		return;
+	}
+	event.preventDefault();
+	try {
+		await host.shutdown();
+	} catch (e) {
+		console.error((e as Error).message);
+	}
+	Deno.exit(0);
+});
+
+// deno desktop binds this to a private local address and opens the window on it, the port given here is ignored
+Deno.serve((req) => {
+	const url = new URL(req.url);
+	if (url.pathname === "/") {
+		// ?server= fills in the address field, without it the field would start with this app's own address.
+		// ?singleplayer shows the singleplayer button, which joins this app's own server
+		const start = new URL("/client/", url);
+		start.searchParams.set("server", default_server);
+		start.searchParams.set("singleplayer", "");
+		return Response.redirect(start, 302);
+	}
+	if (url.pathname === "/ws") {
+		return singleplayer_host().handle(req);
+	}
+	return serve_static(BUILD_DIR, req, url);
+});
+
+// where the app keeps its worlds, the usual place for app data on each os
+function data_dir() {
+	const home = Deno.env.get("HOME") ?? Deno.env.get("USERPROFILE") ?? ".";
+	switch (Deno.build.os) {
+		case "windows":
+			return join(Deno.env.get("APPDATA") ?? join(home, "AppData", "Roaming"), "bworld");
+		case "darwin":
+			return join(home, "Library", "Application Support", "bworld");
+		default:
+			return join(Deno.env.get("XDG_DATA_HOME") ?? join(home, ".local", "share"), "bworld");
+	}
+}

server/host.ts

@@ -0,0 +1,195 @@
+// the part of a game server that has permissions: files and networking. the game itself runs in a worker with none.
+// server/main.ts runs it as a dedicated server, and the desktop app runs it for singleplayer
+import { serveDir } from "@std/http/file-server";
+import { isAbsolute, join } from "@std/path";
+import { GameToHost, HostToGame } from "./game/host_protocol.ts";
+import type { ServerModIndex } from "../build.ts";
+
+const MAX_MESSAGE_SIZE = 4096;
+const SHUTDOWN_TIMEOUT_MS = 5000;
+
+export interface HostOptions {
+	// what deno task build made: the client, assets and mods players download
+	build_dir: string;
+	// the server scripts, with index.json
+	server_mods_dir: string;
+	// what the paths in server_mods/index.json are relative to, the folder the build ran in
+	root: string;
+	world_file: string;
+	seed?: string;
+	// the game can't go on, like the worker crashing
+	on_fatal(message: string): void;
+}
+
+export interface Host {
+	handle(req: Request): Response | Promise<Response>;
+	// saves the world and stops the game. resolves once it's on disk
+	shutdown(): Promise<void>;
+}
+
+export function start_host(options: HostOptions): Host {
+	const mods = read_mods(options);
+	console.log(`Mods: ${mods.mods.map((mod) => `${mod.listing.id} ${mod.listing.version}`).join(", ") || "none"}`);
+
+	const game = new Worker(new URL("./game/worker.ts", import.meta.url), {
+		type: "module",
+		deno: { permissions: "none" },
+	} as WorkerOptions);
+	const post = (message: HostToGame) => game.postMessage(message);
+
+	const sockets = new Map<number, WebSocket>();
+	let next_conn = 1;
+	let on_final_save: (() => void) | undefined;
+
+	game.onmessage = (event: MessageEvent<GameToHost>) => {
+		const message = event.data;
+		switch (message.type) {
+			case "ready":
+				console.log(`World ${options.world_file} ready, seed ${message.seed}`);
+				break;
+			case "failed":
+				options.on_fatal(`Couldn't start the game: ${message.error}`);
+				break;
+			case "send": {
+				const socket = sockets.get(message.conn);
+				if (socket?.readyState === WebSocket.OPEN) {
+					socket.send(message.data);
+				}
+				break;
+			}
+			case "close":
+				sockets.get(message.conn)?.close();
+				break;
+			case "save":
+				write_world(options.world_file, message.data);
+				if (message.final) {
+					console.log("World saved");
+					on_final_save?.();
+				}
+				break;
+		}
+	};
+	game.onerror = (event) => {
+		event.preventDefault();
+		options.on_fatal(`Game server crashed: ${event.message}`);
+	};
+
+	post({
+		type: "init",
+		save: read_world(options.world_file),
+		default_seed: options.seed ?? crypto.randomUUID(),
+		...mods,
+	});
+
+	function handle_socket(socket: WebSocket) {
+		const conn = next_conn++;
+
+		socket.addEventListener("open", () => {
+			sockets.set(conn, socket);
+			post({ type: "connect", conn });
+		});
+
+		socket.addEventListener("message", (event) => {
+			if (typeof event.data !== "string" || event.data.length > MAX_MESSAGE_SIZE) {
+				return;
+			}
+			post({ type: "message", conn, data: event.data });
+		});
+
+		socket.addEventListener("close", () => {
+			if (sockets.delete(conn)) {
+				post({ type: "disconnect", conn });
+			}
+		});
+	}
+
+	return {
+		handle(req) {
+			const url = new URL(req.url);
+			if (url.pathname === "/ws") {
+				if (req.headers.get("upgrade")?.toLowerCase() !== "websocket") {
+					return new Response("Expected a websocket", { status: 426 });
+				}
+				const { socket, response } = Deno.upgradeWebSocket(req);
+				handle_socket(socket);
+				return response;
+			}
+			if (url.pathname === "/") {
+				return Response.redirect(new URL("/client/", url), 302);
+			}
+			return serve_static(options.build_dir, req, url);
+		},
+
+		shutdown() {
+			console.log("Saving world...");
+			return new Promise((resolve, reject) => {
+				const timeout = setTimeout(
+					() => reject(new Error("Game server didn't save in time")),
+					SHUTDOWN_TIMEOUT_MS,
+				);
+				on_final_save = () => {
+					clearTimeout(timeout);
+					game.terminate();
+					resolve();
+				};
+				post({ type: "shutdown" });
+			});
+		},
+	};
+}
+
+function read_world(file: string): string | undefined {
+	try {
+		return Deno.readTextFileSync(file);
+	} catch (e) {
+		if (e instanceof Deno.errors.NotFound) {
+			return undefined;
+		}
+		throw e;
+	}
+}
+
+function write_world(file: string, data: string) {
+	// write then rename so a crash mid write doesnt eat the world
+	Deno.writeTextFileSync(`${file}.tmp`, data);
+	Deno.renameSync(`${file}.tmp`, file);
+}
+
+// what deno task build made. no index means the build failed or never ran, and the game never runs without its mods
+function read_mods(options: HostOptions): Pick<Extract<HostToGame, { type: "init" }>, "mods" | "atlas"> {
+	let index: ServerModIndex;
+	try {
+		index = JSON.parse(Deno.readTextFileSync(join(options.server_mods_dir, "index.json")));
+	} catch {
+		throw new Error(
+			`No ${options.server_mods_dir}/index.json, run deno task build first (it also reports mod errors)`,
+		);
+	}
+	const from_root = (path: string) => isAbsolute(path) ? path : join(options.root, path);
+	return {
+		atlas: index.atlas,
+		mods: index.mods.map(({ listing, server }) => ({
+			listing,
+			data: JSON.parse(Deno.readTextFileSync(join(options.build_dir, listing.data))),
+			server_code: server ? Deno.readTextFileSync(from_root(server)) : undefined,
+			worldgen_code: listing.worldgen
+				? Deno.readTextFileSync(join(options.build_dir, listing.worldgen))
+				: undefined,
+		})),
+	};
+}
+
+// mod files and the atlas are named by their hash, so they never change and pages on other origins can load them
+export async function serve_static(build_dir: string, req: Request, url: URL) {
+	const response = await serveDir(req, { fsRoot: build_dir, quiet: true });
+	const shared = url.pathname.startsWith("/mods/") || url.pathname.startsWith("/assets/");
+	if (shared && response.ok) {
+		const headers = new Headers(response.headers);
+		headers.set("Access-Control-Allow-Origin", "*");
+		if (url.pathname.startsWith("/mods/") || /^\/assets\/sprites\/textures\.[0-9a-f]+\./.test(url.pathname)) {
+			headers.set("Cache-Control", "public, max-age=31536000, immutable");
+		}
+		return new Response(response.body, { status: response.status, statusText: response.statusText, headers });
+	}
+	return response;
+}

server/main.ts

@@ -1,169 +1,41 @@
-import { serveDir } from "@std/http/file-server";
-import { GameToHost, HostToGame } from "./game/host_protocol.ts";
-import type { ServerModIndex } from "../build.ts";
+// a dedicated server: the host from server/host.ts on a port, saving the world when it's stopped
+import { type Host, start_host } from "./host.ts";
 
 const PORT = Number(Deno.env.get("PORT") ?? 8000);
-const WORLD_FILE = Deno.env.get("WORLD_FILE") ?? "world.json";
-const STATIC_ROOT = Deno.env.get("BUILD_DIR") ?? "build";
-const SERVER_MODS_DIR = Deno.env.get("SERVER_MODS_DIR") ?? "server_mods";
-const MAX_MESSAGE_SIZE = 4096;
-const SHUTDOWN_TIMEOUT_MS = 5000;
 
-// the host only does files and networking, the game runs in a worker with no permissions
-const game = new Worker(new URL("./game/worker.ts", import.meta.url), {
-	type: "module",
-	deno: { permissions: "none" },
-} as WorkerOptions);
-
-const sockets = new Map<number, WebSocket>();
-let next_conn = 1;
-
-function post(message: HostToGame) {
-	game.postMessage(message);
-}
-
-function read_world(): string | undefined {
+let host: Host;
 try {
-		return Deno.readTextFileSync(WORLD_FILE);
+	host = start_host({
+		build_dir: Deno.env.get("BUILD_DIR") ?? "build",
+		server_mods_dir: Deno.env.get("SERVER_MODS_DIR") ?? "server_mods",
+		root: ".",
+		world_file: Deno.env.get("WORLD_FILE") ?? "world.json",
+		seed: Deno.env.get("SEED"),
+		on_fatal(message) {
+			console.error(message);
+			Deno.exit(1);
+		},
+	});
 } catch (e) {
-		if (e instanceof Deno.errors.NotFound) {
-			return undefined;
-		}
-		throw e;
-	}
-}
-
-function write_world(data: string) {
-	// write then rename so a crash mid write doesnt eat the world
-	Deno.writeTextFileSync(`${WORLD_FILE}.tmp`, data);
-	Deno.renameSync(`${WORLD_FILE}.tmp`, WORLD_FILE);
-}
-
-game.onmessage = (event: MessageEvent<GameToHost>) => {
-	const message = event.data;
-	switch (message.type) {
-		case "ready":
-			console.log(`World ${WORLD_FILE} ready, seed ${message.seed}`);
-			break;
-		case "failed":
-			console.error(`Couldn't start the game: ${message.error}`);
+	console.error((e as Error).message);
 	Deno.exit(1);
-			break;
-		case "send": {
-			const socket = sockets.get(message.conn);
-			if (socket?.readyState === WebSocket.OPEN) {
-				socket.send(message.data);
 }
-			break;
-		}
-		case "close":
-			sockets.get(message.conn)?.close();
-			break;
-		case "save":
-			write_world(message.data);
-			if (message.final) {
-				console.log("World saved");
-				Deno.exit(0);
-			}
-			break;
-	}
-};
 
-// what deno task build made. no index means the build failed or never ran, and the game never runs without its mods
-function read_mods(): Pick<Extract<HostToGame, { type: "init" }>, "mods" | "atlas"> {
-	let index: ServerModIndex;
+async function shutdown() {
 	try {
-		index = JSON.parse(Deno.readTextFileSync(`${SERVER_MODS_DIR}/index.json`));
-	} catch {
-		console.error(`No ${SERVER_MODS_DIR}/index.json, run deno task build first (it also reports mod errors)`);
+		await host.shutdown();
+		Deno.exit(0);
+	} catch (e) {
+		console.error((e as Error).message);
 		Deno.exit(1);
 	}
-	return {
-		atlas: index.atlas,
-		mods: index.mods.map(({ listing, server }) => ({
-			listing,
-			data: JSON.parse(Deno.readTextFileSync(`${STATIC_ROOT}/${listing.data}`)),
-			server_code: server ? Deno.readTextFileSync(server) : undefined,
-			worldgen_code: listing.worldgen ? Deno.readTextFileSync(`${STATIC_ROOT}/${listing.worldgen}`) : undefined,
-		})),
-	};
-}
-
-game.onerror = (event) => {
-	console.error("Game server crashed:", event.message);
-	Deno.exit(1);
-};
-
-const { mods, atlas } = read_mods();
-console.log(`Mods: ${mods.map((mod) => `${mod.listing.id} ${mod.listing.version}`).join(", ") || "none"}`);
-const save = read_world();
-post({ type: "init", save, default_seed: Deno.env.get("SEED") ?? crypto.randomUUID(), atlas, mods });
-
-// mod files and the atlas are named by their hash, so they never change and pages on other origins can load them
-async function serve_static(req: Request, url: URL) {
-	const response = await serveDir(req, { fsRoot: STATIC_ROOT, quiet: true });
-	const shared = url.pathname.startsWith("/mods/") || url.pathname.startsWith("/assets/");
-	if (shared && response.ok) {
-		const headers = new Headers(response.headers);
-		headers.set("Access-Control-Allow-Origin", "*");
-		if (url.pathname.startsWith("/mods/") || /^\/assets\/sprites\/textures\.[0-9a-f]+\./.test(url.pathname)) {
-			headers.set("Cache-Control", "public, max-age=31536000, immutable");
-		}
-		return new Response(response.body, { status: response.status, statusText: response.statusText, headers });
-	}
-	return response;
-}
-
-function handle_socket(socket: WebSocket) {
-	const conn = next_conn++;
-
-	socket.addEventListener("open", () => {
-		sockets.set(conn, socket);
-		post({ type: "connect", conn });
-	});
-
-	socket.addEventListener("message", (event) => {
-		if (typeof event.data !== "string" || event.data.length > MAX_MESSAGE_SIZE) {
-			return;
-		}
-		post({ type: "message", conn, data: event.data });
-	});
-
-	socket.addEventListener("close", () => {
-		if (sockets.delete(conn)) {
-			post({ type: "disconnect", conn });
-		}
-	});
-}
-
-function shutdown() {
-	console.log("Saving world...");
-	post({ type: "shutdown" });
-	setTimeout(() => {
-		console.error("Game server didn't save in time");
-		Deno.exit(1);
-	}, SHUTDOWN_TIMEOUT_MS);
 }
 Deno.addSignalListener("SIGINT", shutdown);
 if (Deno.build.os !== "windows") {
 	Deno.addSignalListener("SIGTERM", shutdown);
 }
 
-Deno.serve({ port: PORT, onListen: ({ port }) => console.log(`bworld server on http://localhost:${port}/`) }, (req) => {
-	const url = new URL(req.url);
-
-	if (url.pathname === "/ws") {
-		if (req.headers.get("upgrade")?.toLowerCase() !== "websocket") {
-			return new Response("Expected a websocket", { status: 426 });
-		}
-		const { socket, response } = Deno.upgradeWebSocket(req);
-		handle_socket(socket);
-		return response;
-	}
-
-	if (url.pathname === "/") {
-		return Response.redirect(new URL("/client/", url), 302);
-	}
-
-	return serve_static(req, url);
-});
+Deno.serve(
+	{ port: PORT, onListen: ({ port }) => console.log(`bworld server on http://localhost:${port}/`) },
+	host.handle,
+);

tests/server_address_test.ts

@@ -0,0 +1,25 @@
+import { assertEquals, assertThrows } from "@std/assert";
+import { server_address } from "$/client/handshake.ts";
+
+const DESKTOP_PAGE = new URL("http://127.0.0.1:33549/client/");
+const HTTPS_PAGE = new URL("https://bworld.moder.fans/client/");
+
+Deno.test("servers on this machine use ws, everything else wss, whatever the page was served over", () => {
+	for (const host of ["localhost:8000", "127.0.0.1:8000", "0.0.0.0:8000", "[::1]:8000", "localhost"]) {
+		assertEquals(server_address(host, DESKTOP_PAGE).ws_url, `ws://${host}/ws`, host);
+		assertEquals(server_address(host, HTTPS_PAGE).ws_url, `ws://${host}/ws`, host);
+	}
+	for (const host of ["bworld.moder.fans", "example.com:8000", "192.168.1.5:8000", "localhost.example.com"]) {
+		assertEquals(server_address(host, DESKTOP_PAGE).ws_url, `wss://${host}/ws`, host);
+		assertEquals(server_address(host, DESKTOP_PAGE).base.protocol, "https:", host);
+	}
+});
+
+Deno.test("a scheme picks ws or wss itself", () => {
+	assertEquals(server_address("ws://192.168.1.5:8000", DESKTOP_PAGE).ws_url, "ws://192.168.1.5:8000/ws");
+	assertEquals(server_address("http://example.com", DESKTOP_PAGE).base.href, "http://example.com/");
+	assertEquals(server_address("wss://localhost:8000", DESKTOP_PAGE).ws_url, "wss://localhost:8000/ws");
+	assertEquals(server_address("https://bworld.moder.fans/", HTTPS_PAGE).cross_origin, false);
+	assertThrows(() => server_address("", DESKTOP_PAGE));
+	assertThrows(() => server_address("not a host", DESKTOP_PAGE));
+});