//Timer function from this website: http://aktuell.de.selfhtml.org/artikel/javascript/timer/
Function.prototype.Timer = function (interval, calls, onend) {
	var count = 0;
	var payloadFunction = this;
	var startTime = new Date();
	var callbackFunction = function () {
		return payloadFunction(startTime, count);
	};
	var endFunction = function () {
		if (onend) {
			onend(startTime, count, calls);
		}
	};
	var timerFunction = function () {
		count++;
		if (count < calls && callbackFunction() != false) {
			window.setTimeout(timerFunction, interval);
		} else {
			endFunction();
		}
	};
	timerFunction();
};

//leadingzero function from this website: http://aktuell.de.selfhtml.org/artikel/javascript/timer/
function leadingzero (number) {
	return (number < 10) ? '0' + number : number;
}

//countdown function from this website: http://aktuell.de.selfhtml.org/artikel/javascript/timer/
//edited by hitzi
function countdown (seconds, target) {
	var element = document.getElementById(target);
	var calculateAndShow = function () {
		if (seconds >= 0) {
      		var h = Math.floor(seconds / 3600);
      		var m = Math.floor((seconds % 3600) / 60);
      		var s = seconds % 60;
      		element.innerHTML=
        	leadingzero(h) + ':' +
        	leadingzero(m) + ':' +
        	leadingzero(s);
      		seconds--;
    	} else {
			return false;
		}
	};

	var completed = function () {
		element.innerHTML = "over";
	};
	calculateAndShow.Timer(1000, Infinity, completed);
}