//add event function from http://www.dynarch.com/projects/calendar/
function addAnEvent(el, evname, func) {
    if (el.attachEvent) { // IE
        el.attachEvent("on" + evname, func);
    } else if (el.addEventListener) { // Gecko / W3C
        el.addEventListener(evname, func, true);
    } else {
        el["on" + evname] = func;
    }
}

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
function drawSliderByVal(slider) {
	var knob=slider.getElementsByTagName('span')[0];
	var pSlider=(slider.slidervalue-slider.min)/(slider.max-slider.min);
	var xSlider=(slider.scrollWidth-6)*pSlider;
	knob.style.width=xSlider+"px";
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
function setSliderByClientX(slider, clientX) {
	var pSlider=(clientX-slider.offsetLeft-0)/(slider.scrollWidth-6);
	slider.slidervalue=(slider.max-slider.min)*pSlider + slider.min;
	if (slider.slidervalue>slider.max) slider.slidervalue=slider.max;
	if (slider.slidervalue<slider.min) slider.slidervalue=slider.min;

	drawSliderByVal(slider);
	slider.onchange(slider.slidervalue, slider.num);
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
function sliderClick(e) {
	var el=sliderFromEvent(e);
	if (!el) return;

	setSliderByClientX(el, e.clientX);
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
function sliderMouseMove(e) {
	var el=sliderFromEvent(e);
	if (!el) return;
	if (activeSlider<0) return;

	setSliderByClientX(el, e.clientX);
	stopEvent(e);
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
function sliderFromEvent(e) {
	if (!e && window.event) e=window.event;
	if (!e) return false;

	var el;
	if (e.target) el=e.target;
	if (e.srcElement) el=e.srcElement;

	if (!el.id || !el.id.match(/slider\d+/)) el=el.parentNode;
	if (!el) return false;
	if (!el.id || !el.id.match(/slider\d+/)) return false;

	return el;
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
function attachSliderEvents() {
	var divs=document.getElementsByTagName('div');
	var divNum;
	for(var i=0; i<divs.length; i++) {
		if (divNum=divs[i].id.match(/\bslider(\d+)\b/)) {
			// set initial properties
			divNum=parseInt(divNum[1]);
			divs[i].min=slider[divNum].min;
			divs[i].max=slider[divNum].max;
			divs[i].slidervalue=slider[divNum].slidervalue;
			divs[i].onchange=slider[divNum].onchange;
			divs[i].num=divNum;
			// and make sure the display matches
			drawSliderByVal(divs[i]);
			divs[i].onchange(divs[i].slidervalue, divNum);

			addAnEvent(divs[i], 'mousedown', function(e){
				sliderClick(e);
				var el=sliderFromEvent(e);
				if (!el) return;
				activeSlider=el.num;
				stopEvent(e);
			});
			addAnEvent(divs[i], 'mouseup', function(e){
				activeSlider=-1;
				stopEvent(e);
			});
		}
	}
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
//borrowed from prototype: http://prototype.conio.net/
function stopEvent(event) {
	if (event.preventDefault) {
		event.preventDefault();
		event.stopPropagation();
	} else {
		event.returnValue=false;
		event.cancelBubble=true;

	}
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
addAnEvent(window, 'load', attachSliderEvents);
addAnEvent(document, 'mousemove', sliderMouseMove);
var activeSlider=-1;
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */