import flash.events.Event;
import flash.text.TextField;

var endDate:Date = new Date(2015, 11, 30, 21, 0, 0, 0);
var timer:TextField;

addEventListener(Event.ENTER_FRAME, enterFrame);

function enterFrame(e:Event):void {
	var now:Date = new Date();
	var diff:Number = ( (endDate.time - now.time) / 1000);
	
	if (diff > 0) {
		var days:int = Math.floor(diff / (3600*24));
		diff %= (3600 * 24);
		
		var hours:int = Math.floor(diff / 3600);
		diff %= 3600;
		
		var minutes:int = Math.floor(diff / 60);
		diff %= 60;
		
		var seconds:int = diff;
	
		timer.text = zeroPad(days) + ":" +
                     zeroPad(hours) + ":" + 
                     zeroPad(minutes) + ":" +
                     zeroPad(seconds);
	}
	else {
		timer.text = "00:00:00:00";
	}
}

function zeroPad(num:int):String {
	return ("0" + num).substr(-2);
}