#!/bin/env -S deno run --allow-net

import { MsgToClient, MsgToServer, mts } from "../common/mod.ts";
import { channel, log_from, parsed_stream, Receiver, Sender, serialized_stream } from "../common/utils.ts";
const log = log_from(import.meta);

export class Gateway {
	server;
	constructor(port: number) {
		this.server = Deno.listen({ port });
		log("Listening on", port);
	}
	async *accept() {
		for await (const connection of this.server) {
			const session = await ClientInterface.init(connection);
			log("New session.");
			yield session;
		}
	}
}

export class ClientInterface {
	inputs;
	outputs;

	constructor(inputs: Receiver<MsgToServer>, outputs: Sender<MsgToClient>) {
		this.inputs = inputs;
		this.outputs = outputs;
	}

	// deno-lint-ignore require-await
	static async init(connection: Deno.Conn) {
		// TODO : handshake ?
		const [input_sender, input_receiver] = channel<MsgToServer>();
		const [output_sender, output_receiver] = channel<MsgToClient>();
		input_sender.send_all(parsed_stream(mts.message_to_server_parser())(connection.readable))
			.finally(() => input_sender.send({ kind: "exit" }));
		serialized_stream(output_receiver.iter())(connection.writable)
			.finally(() => input_sender.send({ kind: "exit" }));
		return new ClientInterface(input_receiver, output_sender);
	}
}