Simple timer with JS

timer.js

/**
 * @param seconds - time
 * @param tick - callback
 * @param result - callback
 */
function timer (seconds, tick, result) {
	if (seconds > 0) {
		tick(seconds);
		seconds -= 1;
		setTimeout(function () {
			timer(seconds, tick, result);
		}, 1000);
	} else {
		result();
	}
}

Example for using

timer(15, function (s) {
    console.log(s + ' second has passed!');
}, function () {
    console.log('Time is over!');
});

Read post