'use strict';

const net = require("net");
const Promise = require("bluebird");

function listening(port, cb) {
	let done = false;
	let sock = new net.Socket();
	sock.setTimeout(50);
	sock.on("connect", () => {
		done = true;
		cb(null, true);
		sock.destroy();
	}).on("timeout", () => {
		if (done) { return; }
		cb(null, false);
	}).on("error", (err) => {
		if (done) { return; }
		cb(null, false);
	}).connect(port);
}

function waitForServer(port, cb) {
	setTimeout(() => {
		listening(port, (err, isListening) => {
			if (err != null) {
				cb(err);
			} else {
				if (isListening) {
					cb(null, true);
				} else {
					waitForServer(port, cb);
				}
			}
		});
	}, 100);
}

module.exports = function serverWaiter(port) {
	let isWaiting = false;

	return {
		reportRestart: function() {
			isWaiting = true;
		},
		isWaiting: function() {
			return isWaiting;
		},
		wait: function() {
			return Promise.try(() => {
				return Promise.promisify(waitForServer)(port);
			}).then((result) => {
				isWaiting = false;
			});
		}
	}
}