var IS_SLIDING	= false; // prevents slider from initiating while a slide is in progress
var lisVisible	= 3; // the amount of <li> elements that slide at a time
var slideLength	= 960; 
var slideTime	= 800; // time it takes to move from one slide to another
var slideAuto	= true; // if set to false, the slider does not slide automatically


function moveRight(keepMoving) {
	if (!keepMoving) {
		slideAuto = false;
	}
	var holder	= document.getElementById('main_feature_extend');
	var totalLi = holder.getElementsByTagName('li').length;
	var len		= slideLength;
	var newLen	= (holder.style.marginLeft) ? parseInt(holder.style.marginLeft)-slideLength : slideLength;
		newLen	= Math.abs(newLen);
		//alert("\n\rnewLen = "+newLen+"\n\rtotalLi = "+totalLi+"\n\rMath.ceil(totalLi/3) = "+Math.ceil(totalLi*3)+"\n\rlen * Math.ceil(totalLi*3) = "+len * Math.ceil(totalLi/3)+"");
	var maxRight = len * Math.ceil(totalLi/lisVisible);
	if (newLen == maxRight) {
		newLen = 0;
		if (!IS_SLIDING) {
			IS_SLIDING=true;
			$('#main_feature_extend').animate({
				marginLeft: newLen
			},slideTime,function() {IS_SLIDING=false;});
			//changeSlider(-newLen);
		}
	} else {
		if (!IS_SLIDING) {
			IS_SLIDING=true;
			$('#main_feature_extend').animate({
				marginLeft: -newLen
			},slideTime,function() {IS_SLIDING=false;});
			//changeSlider(-newLen);
		}
	}
}

function moveLeft() {
	slideAuto = false; // since it doesn't auto slide left, it must've been clicked so freeze it
	var holder	= document.getElementById('main_feature_extend');
	var totalLi = holder.getElementsByTagName('li').length;
	var len		= slideLength;
	var newLen	= (holder.style.marginLeft) ? parseInt(holder.style.marginLeft)-slideLength : slideLength;//(holder.style.marginLeft) ? parseInt(holder.style.marginLeft)+len : len;
		newLen	= Math.abs(newLen);
	var maxRight = len * Math.ceil(totalLi/lisVisible);
	if (newLen != slideLength) {
		var newLen = newLen;//Math.ceil((newLen*(totalLi-1))/lisVisible); // len * Math.ceil(totalLi/lisVisible);
		if (!IS_SLIDING) {
			IS_SLIDING=true;
			//alert(" -(newLen-slideLength*2) = "+(-(newLen-slideLength*2))+"\n\r newLen = "+newLen+"\n\r slideLength = "+slideLength+"\n\r slideLength*2 = "+slideLength*2);
			$('#main_feature_extend').animate({
				marginLeft: -(newLen-slideLength*2)
			},slideTime,function() {IS_SLIDING=false;});
			//changeSlider(-newLen);
		}
	} else {
		if (!IS_SLIDING) {
			IS_SLIDING=true;
			$('#main_feature_extend').animate({
				marginLeft: -(maxRight-newLen)
			},slideTime,function() {IS_SLIDING=false;});
			//changeSlider(-newLen);
		}
	}
}

window.onload=function() {
	if (document.getElementById('arrow-left')) {
		document.getElementById('arrow-left').onclick = function(){moveLeft();}
		document.getElementById('arrow-right').onclick= function(){moveRight();}
	
		mf=document.getElementById('main_feature_extend');
		lis=mf.getElementsByTagName('li').length;
		mfe=document.getElementById('main_feature_extend');
		for(var i=0;i<mfe.getElementsByTagName('li').length;i++){
			mfe.getElementsByTagName('li')[i].id = 'main_feature'+(i+1);
		}
	
		var h3 = document.getElementById('main_feature1').childNodes;
		for(var i=0;i<h3.length;i++){
			if(h3[i].tagName && h3[i].tagName.toLowerCase() == 'h3') {
				if (document.getElementById('featureText')) {
					document.getElementById('featureText').innerHTML = h3[i].innerHTML;
				}
			}
		}
	}
}