/*
Simple Image Trail script- By JavaScriptKit.com
Visit http://www.javascriptkit.com for this script and more
This notice must stay intact
*/

var offsetfrommouse=[36,36]; //image x,y offsets from cursor position in pixels. Enter 0,0 for no offset
var displayduration=0; //duration in seconds image should remain visible. 0 for always.

var defaultimageheight = 40;	// maximum image size.
var defaultimagewidth = 40;	// maximum image size.

var timer;

function gettrailobj(){
if (document.getElementById)
return document.getElementById("preview_div_22").style
}

function gettrailobjnostyle(){
if (document.getElementById)
return document.getElementById("preview_div_22")
}


function truebody(){
return (!window.opera && document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body
}


function hidetrail(){	
	gettrailobj().display= "none";
	document.onmousemove=""
	gettrailobj().left="-500px"
	clearTimeout(timer);
}

function showtrail(imagename,title,width,height){
	i = imagename
	t = title
	w = width
	h = height
	timer = setTimeout("show('"+i+"',t,w,h);",50);
}
function show(imagename,title,width,height){
 
    var docwidth=document.all? truebody().scrollLeft+truebody().clientWidth : pageXOffset+window.innerWidth - offsetfrommouse[0]
	var docheight=document.all? Math.min(truebody().scrollHeight, truebody().clientHeight) : Math.min(window.innerHeight)
	
	if( (navigator.userAgent.indexOf("Konqueror")==-1  || navigator.userAgent.indexOf("Firefox")!=-1 || (navigator.userAgent.indexOf("Opera")==-1 && navigator.appVersion.indexOf("MSIE")!=-1)) && (docwidth>650 && docheight>500)) {
		( width == 0 ) ? width = defaultimagewidth: '';
		( height == 0 ) ? height = defaultimageheight: '';
			
		width+=30;
		height+=55;
		defaultimageheight = height;
		defaultimagewidth = width;
		document.onmousemove=followmouse;
		newHTML = '';
		
		newHTML = newHTML + '<div class="title_h2">' + ' '+title + '</div>'
		newHTML = newHTML + '<div id="loader_container"><div id="loader"><div align="center">正在加载图片……</div><div id="loader_bg"><div id="progress"> </div></div></div></div>';
    	newHTML = newHTML + '<div class="preview_temp_load" style="display:none;"><img onload="javascript:remove_loading();preview_templates_DrawImage(this,'+ (height-30) +','+ (height-50) +')" src="' + imagename + '" border="0"></div>';
		
		newHTML = '<div class="border_preview" style="width:'+ (width+10) +'px;">' + newHTML + '</div>'; 
		
		gettrailobjnostyle().innerHTML = newHTML;
		gettrailobj().display="block";		
	}
}
function followmouse(e){

	var xcoord=offsetfrommouse[0]
	var ycoord=offsetfrommouse[1]

	var docwidth=document.all? truebody().scrollLeft+truebody().clientWidth : pageXOffset+window.innerWidth-15
	var docheight=document.all? Math.min(truebody().scrollHeight, truebody().clientHeight) : Math.min(window.innerHeight)

	if (typeof e != "undefined"){
		if (docwidth - e.pageX < defaultimagewidth + 2*offsetfrommouse[0]){
			xcoord = e.pageX - xcoord - defaultimagewidth; // Move to the left side of the cursor
		} else {
			xcoord += e.pageX;
		}
		if (docheight - e.pageY < defaultimageheight + 2*offsetfrommouse[1]){
			ycoord += e.pageY - Math.max(0,(2*offsetfrommouse[1] + defaultimageheight + e.pageY - docheight - truebody().scrollTop));
		} else {
			ycoord += e.pageY;
		}

	} else if (typeof window.event != "undefined"){
		if (docwidth - event.clientX < defaultimagewidth + 2*offsetfrommouse[0]){
			xcoord = event.clientX + truebody().scrollLeft - xcoord - defaultimagewidth; // Move to the left side of the cursor
		} else {
			xcoord += truebody().scrollLeft+event.clientX
		}
		if (docheight - event.clientY < (defaultimageheight + 2*offsetfrommouse[1])){
			ycoord += event.clientY + truebody().scrollTop - Math.max(0,(2*offsetfrommouse[1] + defaultimageheight + event.clientY - docheight));
		} else {
			ycoord += truebody().scrollTop + event.clientY;
		}
	}
	gettrailobj().left=xcoord+"px"
	gettrailobj().top=ycoord+"px"
}
function preview_templates_DrawImage(ImgD,iwidth,iheight){
	//参数(图片,允许的宽度,允许的高度)
	var image=new Image();
	ImgD.parentNode.style.display = "";
	image.src=ImgD.src;
	if(image.width>0 && image.height>0){
		flag=true;
		if(image.width/image.height>= iwidth/iheight){
			if(image.width>iwidth){ 
				ImgD.width=iwidth;
				ImgD.height=(image.height*iwidth)/image.width;
			}else{
				ImgD.width=image.width; 
				ImgD.height=image.height;
			}
		}else{
			if(image.height>iheight){ 
				ImgD.height=iheight;
				ImgD.width=(image.width*iheight)/image.height; 
			}else{
				ImgD.width=image.width; 
				ImgD.height=image.height;
			}
		}
	}
}