function xmlHTTP() {
  if ( window.XMLHttpRequest ) // Gecko
    return new XMLHttpRequest() ;
  else if ( window.ActiveXObject ) // IE
    return new ActiveXObject("MsXml2.XmlHttp") ;
}

function load_banners(){
  var horizontal_banners = document.getElementById("horizontal-banners");
  var vertical_banners = document.getElementById("vertical-banners");
  var index_banners = document.getElementById("index-banners");

  if(vertical_banners){
    drawBannersIframe('vertical');
  }

  if(horizontal_banners){
    drawBannersIframe('horizontal');
  }

  if(index_banners){
    drawBannersIframe('index');
  }
}

function drawBannersIframe(type) {
  var rnd = Math.round(Math.random() * 10000);
  var url = '/banner/show/'
   + '?place=' + escape(document.location.pathname)
   + ';type=' + type
   + ';rand=' + rnd;

  var b = xmlHTTP();
  b.onreadystatechange = function () {
    if (b.readyState==4) {
      place_banners(type, b.responseText);
    }
  }
  b.open("GET",url, true);
  b.send(null);
}

function place_banners(type, banners){
  var horizontal_banners = document.getElementById("horizontal-banners");
  var vertical_banners = document.getElementById("vertical-banners");
  var index_banners = document.getElementById("index-banners");

  if(type=='horizontal' && horizontal_banners){
    horizontal_banners.innerHTML=banners;
  }

  if(type=='vertical' && vertical_banners){
    vertical_banners.innerHTML=banners;
  }

  if(type=='index' && index_banners){
    index_banners.innerHTML=banners;
  }
}