Init.

src/main.ts

@@ -0,0 +1,133 @@
+#!/usr/bin/env -S deno run -A
+
+import { writeAll } from "https://deno.land/std@0.224.0/io/mod.ts"
+import { mkSimplexNoise, SimplexNoise } from "npm:@spissvinkel/simplex-noise@1.0.1"
+
+async function main() {
+	const connections = Listener.listen(8080)
+	const fishes = await Fishes.load("./assets/fishes")
+	for await (const moved of fishes.movements()) {
+		console.log(moved.name, "at", moved.position)
+		const displayed = esc_clear() + fishes.fishes.map(display).join("") + "\n"
+		connections.send(displayed)
+	}
+}
+
+class Listener {
+	private constructor(
+		private connections: Set<Deno.TcpConn>,
+	) {}
+
+	public static listen(port: number) {
+		const connections = new Set<Deno.TcpConn>()
+		;(async () => {
+			for await (const conn of Deno.listen({ transport: "tcp", port })) connections.add(conn)
+		})()
+		return new Listener(connections)
+	}
+
+	public async send(text: string) {
+		const encoded = new TextEncoder().encode(text)
+		const promises = new Array<Promise<unknown>>()
+		for (const conn of this.connections) {
+			const promise = writeAll(conn, encoded).catch((_) => this.connections.delete(conn))
+			promises.push(promise)
+		}
+		await Promise.all(promises)
+	}
+}
+
+class Fishes {
+	private constructor(
+		public fishes: Fish[],
+	) {}
+
+	public static async load(path: string, max = 999) {
+		const fishes = new Array<Fish>()
+		for await (const entry of Deno.readDir(path)) {
+			if (fishes.length >= max) break
+			if (!entry.isFile) continue
+			if (!entry.name.endsWith(".txt")) continue
+			const name = entry.name.slice(0, entry.name.length - ".txt".length)
+			const file_path = `${path}/${entry.name}`
+			const content = await Deno.readTextFile(file_path)
+			const shape = content.split("\n").filter((l) => l.length > 0)
+			const size: [number, number] = [shape.map((l) => l.length).reduce((a, b) => Math.max(a, b)), shape.length]
+			fishes.push(new Fish(name, size, shape, [Math.random() * 20, Math.random() * 20]))
+		}
+		console.log("Loaded", fishes.length, "fishes.")
+		return new Fishes(fishes)
+	}
+
+	public async *movements() {
+		const noise = mkSimplexNoise(Math.random)
+		while (true) {
+			const picked = pick(this.fishes)
+			picked.move_into(noise, [[0, 0], [80, 25]])
+			yield picked
+			await new Promise((res) => setTimeout(res, 200))
+		}
+	}
+}
+
+class Fish {
+	public constructor(
+		public name: string,
+		public size: [x: number, y: number],
+		public shape: string[],
+		public position: [number, number] = [0, 0],
+		public age = 0,
+	) {}
+
+	public move_into(noise: SimplexNoise, bounds: [[number, number], [number, number]]) {
+		const base = [...this.name].map((c) => c.charCodeAt(0)).reduce((a, b) => a + b)
+		const velocityX = noise.noise2D(this.age % 100, base)
+		const velocityY = noise.noise2D(this.age % 100, base + 100)
+		this.position[0] += velocityX
+		this.position[1] += velocityY
+		this.age += 1
+		if (this.position[0] < bounds[0][0]) this.position[0] = bounds[0][0]
+		if (this.position[1] < bounds[0][1]) this.position[1] = bounds[0][1]
+		if (this.position[0] > bounds[1][0]) this.position[0] = bounds[1][0]
+		if (this.position[1] > bounds[1][1]) this.position[1] = bounds[1][1]
+	}
+}
+
+/**
+ * ```
+ *       _ <name>
+ *      /
+ * #####
+ * #####
+ * #####
+ * ```
+ *
+ * @param fish Fish to display.
+ */
+function display(fish: Fish) {
+	const tick_pad = " ".repeat(fish.size[0])
+	// TODO : add position and color
+	return [
+		tick_pad + " _ " + fish.name,
+		tick_pad + "/",
+		...fish.shape,
+	]
+		.map((l, i) => esc_goto([fish.position[0], fish.position[1] + i]) + l)
+		.join("") + "\n"
+}
+
+function pick<T>(arr: T[], random = Math.random) {
+	const index = Math.floor(random() * arr.length)
+	return arr[index]
+}
+
+function esc_goto(pos: [number, number]) {
+	const [x, y] = pos.map(Math.floor)
+	return "\u001B[" + y + ";" + x + "H"
+}
+
+function esc_clear() {
+	return "\u001B[3J"
+}
+
+if (import.meta.main) await main()