var d = document;
var detect = false;
var dclose = false; 

get_doc_height = function () 
{
    return Math.max(
    Math.max(d.body.scrollHeight, d.documentElement.scrollHeight),
    Math.max(d.body.offsetHeight, d.documentElement.offsetHeight),
    Math.max(d.body.clientHeight, d.documentElement.clientHeight)
    );
}

get_doc_width = function () 
{
    return Math.max(
    Math.max(d.body.scrollWidth, d.documentElement.scrollWidth),
    Math.max(d.body.offsetWidth, d.documentElement.offsetWidth),
    Math.max(d.body.clientWidth, d.documentElement.clientWidth)
    );
}

show_obj = function(obj_id, show_darker)
{
    if(!detect) tb_detectMacXFF();
    
    if(show_darker)
    {
        var darker = d.getElementById('darker');
        darker.style.display = 'block';
    }
    
    dclose = false;
    
    var obj = d.getElementById(obj_id);

    obj.style.display = 'block';
    obj.style.top = (get_doc_height() / 2) - (obj.clientHeight / 2) + 'px';
    obj.style.left = (get_doc_width() / 2) - (obj.clientWidth / 2) + 'px';
}

close_obj = function(obj_id, close_darker)
{
    if(close_darker || dclose)
    {
        var darker = d.getElementById('darker');
        darker.style.display = 'none';
    }
    
    dclose = false;
    
    var obj = d.getElementById(obj_id);
    obj.style.display = 'none';
}

tb_detectMacXFF = function() 
{
     detect = true;
     var userAgent = navigator.userAgent.toLowerCase();
     if(userAgent.indexOf('mac') != -1 && userAgent.indexOf('firefox')!=-1) 
     {
          d.getElementById('darker').className = 'TB_overlayMacFFBGHack';
     }
     else d.getElementById('darker').className = 'TB_overlayBG';
}