// This file is part of cwait, copyright (c) 2015-2016 BusFaster Ltd.
// Released under the MIT license, see LICENSE.

declare var process: any;

import * as Promise from 'bluebird';
import {TaskQueue} from '..';

function equals(a: any, b: any) {
	if(a != b) {
		console.log('ERROR ' + a + ' != ' + b);
		process.exit(1);
	}

	console.log('OK ' + a);
}

var testCount = 0;

function test1() {
	/** Queue allowing 3 concurrent function calls. */
	var queue = new TaskQueue(Promise, 3);

	var running = 0;
	var maxRunning = 0;

	/** Test function returning a promise with a slight delay
	  * and tracking concurrent executions. */

	function run(item: string) {
		if(++running > maxRunning) maxRunning = running;

		return(Promise.delay(100, true).then(() => {
			--running;
			return(item);
		}));
	}

	/** List of 6 items to loop through. */
	var list = '123456'.split('');

	// Run test without limiting concurrency.

	return(
		Promise.map(list, run).then((result: string[]) => {
			++testCount;

			equals(result.join(''), '123456');
			equals(maxRunning, 6);

			maxRunning = 0;

			// Run test and limit concurrency.

			return(Promise.map(list, queue.wrap(run)))
		}).then((result: string[]) => {
			++testCount;

			equals(result.join(''), '123456');
			equals(maxRunning, 3);
		})
	);
}

function test2() {
	function throws() {
		if(1) throw(new Error('Beep'));

		return(Promise.resolve(true));
	}

	var queue = new TaskQueue(Promise, 1);

	return(
		Promise.all([
			queue.wrap(throws)().then(null as any, (err: any) => ++testCount),
			queue.wrap(throws)().then(null as any, (err: any) => ++testCount)
		])
	);
}

function test3() {
	function rejects() {
		return(Promise.reject(new Error('Beep')));
	}

	var queue = new TaskQueue(Promise, 1);

	return(
		Promise.all([
			queue.wrap(rejects)().then(null as any, (err: any) => ++testCount),
			queue.wrap(rejects)().then(null as any, (err: any) => ++testCount)
		])
	);
}

function test4() {
	const unsorted: number[] = [];

	function compare(a: number, b: number) { return(a - b); }

	for(let num = 0; num < 100; ++num) {
		unsorted[num] = ~~(Math.random() * 50);
	}

	const correct = unsorted.slice(0).sort(compare);

	const queue = new TaskQueue(Promise, 1);
	const result: number[] = [];
	const start = new Date().getTime();

	return(
		Promise.map(
			unsorted,
			(item: number) => queue.add(
				() => {
					const delta = new Date().getTime() - start - item * 10;
					if(delta > 0 && delta < 20) result.push(item);
				},
				item * 10
			)
		).then(
			() => result.join(' ') == correct.join(' ') && ++testCount
		)
	);
}


Promise.all([
	test1(),
	test2(),
	test3(),
	test4()
]).then(
	() => equals(testCount, 7)
);