var xmlHttp
var mediaid = 0;

function checkout(mediaid, comment, checkout, t)
{
    xmlHttp=GetXmlHttpObject()
    
    if (xmlHttp==null)
    {
          alert ("Your browser does not support AJAX!");
          return;
    }
    
    this.mediaid = mediaid;
       
    var url="ajax_checkout.php";
    url=url+"?MediaID="+mediaid;
    url=url+"&t="+t;
    url=url+"&checkout_comment="+comment;
    url=url+"&checkout="+checkout;   
    url=url+"&sid="+Math.random();

    
    xmlHttp.onreadystatechange=stateChangedCheckout;
    
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null);
    
    
}

function stateChangedCheckout() 
{ 
    if (xmlHttp.readyState==4)
    { 
        if(xmlHttp.responseText == "Checked out.") {
            document.getElementById("checkout_comment"+mediaid).disabled=true;
            document.getElementById("checkout"+mediaid).value="Check-in";
            document.getElementById("mediaid"+mediaid).style.background='#FFEAEA';
        }
        else if(xmlHttp.responseText == "Checked in.") {
            document.getElementById("checkout_comment"+mediaid).value="";
            document.getElementById("checkout_comment"+mediaid).disabled=false;
            document.getElementById("checkout"+mediaid).value="Check-out";
            document.getElementById("mediaid"+mediaid).style.background='#C0FFC0';
        }
        else {
            alert("Error:"+xmlHttp.responseText);
        }
    }
}

function GetXmlHttpObject()
{
    var xmlHttp=null;
    try
      {
          // Firefox, Opera 8.0+, Safari
          xmlHttp=new XMLHttpRequest();
      }
    catch (e)
      {
      // Internet Explorer
      try
        {
            xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
        }
      catch (e)
        {
            xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
        }
      }
    return xmlHttp;
}