var xmlHttp;
var basePath="";
var index=0;
var pic_num=7;
 
var currentOpacity=0;
var minOpacity;
var maxOpacity;
var step=0;

function createXMLHttp(){
	if(window.ActiveXObject){
		xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
	}else if(window.XMLHttpRequest){
		xmlHttp=new XMLHttpRequest();
	}
}

function getOpac(){
	if(document.all){
		minOpacity=0;
		maxOpacity=100;
		step=10;
	}else{
		minOpacity=0;
		maxOpacity=1;
		step=0.1;
	}
}

function next(){
	getOpac();
	index++;
	check_index();
	show_pic();
}

function pre(){
	getOpac();
	index--;
	check_index();
	show_pic();
}

function check_index(){
	if(index>pic_num) index=1;
	if(index<0) index=pic_num;
}

function show_pic(){
	createXMLHttp();
	xmlHttp.onreadystatechange=load_pic;
	xmlHttp.open("GET","index.php?m=ajax&a=index_images_xml",true);
	xmlHttp.send(null);
}

function load_pic(){
	document.getElementById("picContainer").innnerHTML="Loading...";
	if (xmlHttp.readyState == 4) {
		var picContainer=document.getElementById("picContainer");
		picContainer.innerHTML="";
		var xmlDocumentElement=xmlHttp.responseXML.documentElement;
		var pics=xmlDocumentElement.getElementsByTagName("photo");
		for(var i=0;i<pics.length;i++){
			var pic=pics[i];
			var pic_id=pic.getElementsByTagName("id")[0].firstChild.nodeValue;
			if(i+1!=index) continue;
			else{
				var pic_src=pic.getElementsByTagName("name")[0].firstChild.nodeValue;
				var pic_title=pic.getElementsByTagName("title")[0].firstChild.nodeValue;
				fade_pic(pic_src,pic_title,pic_id);
			}
		}	
	}
}

function fade_pic(pic_src,pic_title,pic_id){
	var picContainer=document.getElementById("picContainer");
	var pic_state=document.getElementById("title");
	picContainer.innerHTML="<img border=0 src='"+basePath+pic_src+"' alt=''>";
	pic_state.innerHTML="<a href='index.php?m=product&a=show&id="+pic_id+"'>"+pic_title+"</a>";
	fadeIn("picContainer");
}

function fadeIn(div){
	setOpacity(div);
	currentOpacity=currentOpacity+step;
	if(currentOpacity<=maxOpacity){
		setTimeout("fadeIn('"+div+"')",50);
	}else if(currentOpacity>maxOpacity){
		currentOpacity=minOpacity;
	}
}

function setOpacity(div){
	var pic=document.getElementById(div);
	if(document.all){
		pic.style.filter="alpha(opacity="+currentOpacity+")";
	}else{
		pic.style.opacity=currentOpacity;
	}
}

function show_nav(type,div){
	var elem=document.getElementById(div);
	if(type="show"){
		elem.style.display="block";
	}
	if(type="hide"){
		elem.style.display="none";
	}
}

/*setInterval("next()",10000);*/