Countdown Timer

CountdownTimer.js

function CountdownTimer(from, end) {
    var ct = this;
    var ONE_HOUR = 1000 * 60 * 60;
    var ONE_MIN = 1000 * 60;
    var ONE_SEC = 1000;
    var startFrom = new Date(from);
    var endAt = new Date(end);
    var diff = endAt - startFrom;
    var parseTime = function () {
            ct.hour = Math.floor(diff / ONE_HOUR);
            if (ct.hour > 0) diff = diff - (ct.hour * ONE_HOUR);

            ct.min = Math.floor(diff / ONE_MIN);
            if (ct.min > 0) diff = diff - (ct.min * ONE_MIN);

            ct.sec = Math.floor(diff / ONE_SEC);

			console.log(ct.sec);
            startFrom.setSeconds(startFrom.getSeconds() + 1);

            diff = endAt - startFrom;
        }

    this.isTimeup = false;

    this.count = function () {
        var timer = setInterval(function () {
            parseTime();
            if (diff <= 0) {
                ct.isTimeup = true;
                clearInterval(timer);
            }
        }, 1000);
    }
}