window.onload = prepareLinks;

function getHTTPObject(){
 var xhr = false;
 if(window.XMLHttpRequest){
 xhr = new XMLHttpRequest();
 }
 else if (window.ActiveXObject){
  try {
   xhr = new ActiveXObject("Msxml2.XMLHTTP");
  } catch(e){
   try {
    xhr = new ActiveXObject("Microsoft.XMLHTTP"); 
   } catch(e) {
   xhr = false;
   }
  } 
 }
 return xhr;
}

function grabFile(file) {
 var request = getHTTPObject();
 if(request){
  displayLoading(document.getElementById("result"));
  request.onreadystatechange = function() {
  parseResponse(request);
  };
  request.open("GET", file, true);
  request.send(null);
  return true;
 }else {
 return false;
 }
}

function parseResponse(request) {
 if(request.readyState == 4) {
  if(request.status==200 || request.status == 304) {
  var result = document.getElementById("result");
  result.innerHTML = request.responseText;
  }
 }
}


function prepareLinks() {
 if(!document.getElementById || !document.getElementsByTagName){
  alert("Problem");
  return;
 }
 else
 {
 alert("Ajax Enabled...Play now...");
 }
 var list = document.getElementById("result");
 var links = list.getElementsByTagName("a");
  for(var i=0; i<links.length; i++) {
   links[i].onclick = function (){
     var query = this.getAttribute("href").split("?")[1];
     var url = "stroop_decision_ajax.php?"+query;
     //alert(url);
     return !grabFile(url);
   }
  }
}

function displayLoading(element) {
 var image = document.createElement("img");
 image.setAttribute("src","../images/progressbar.gif");
 image.setAttribute("alt", "Loading...");
 element.appendChild(image);
}