var offsetfrommouse=[20,20]; 
var displayduration=0; 

var defaultimageheight = 40;  
var defaultimagewidth = 40;  

var timer;

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

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


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);",200);
}
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+=30
    defaultimageheight = height
    defaultimagewidth = width
  
    document.onmousemove=followmouse; 

    
    newHTML = '<div class="border_preview" style="width:'+  width +'px;height:'+ height +'px"><div id="loader_container"><div id="loader_preview"><div align="center">正在载入圖片...</div></div></div>';
    /* newHTML = newHTML + '<h2 class="title_h2">' + ' '+title + '</h2>' */
    
    newHTML = newHTML + '<div class="preview_temp_load"><img onload="javascript:remove_loading();" src="' + imagename + '" border="0"></div>';
    newHTML = newHTML + '</div>'; 
    
    if(navigator.userAgent.indexOf("MSIE")!=-1 && navigator.userAgent.indexOf("Opera")==-1 ){
      newHTML = newHTML+'<iframe src="about:blank" scrolling="no" frameborder="0" width="'+width+'" height="'+height+'"></iframe>';
    }    

    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;
    } 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;
    } 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 animate() {}
var t_id = setInterval(animate,20);
var pos=0;
var dir=2;
var len=0;
function remove_loading() {
this.clearInterval(t_id);
var targelem = document.getElementById('loader_container');
targelem.style.display='none';
targelem.style.visibility='hidden';
var t_id = setInterval(animate,60);
}