function encrypt(str, pwd) {
  if(pwd == null || pwd.length <= 0) {
    alert("Please enter a password with which to encrypt the message.");
    return null;
  }
  var prand = "";
  for(var i=0; i<pwd.length; i++) {
    prand += pwd.charCodeAt(i).toString();
  }
  var sPos = Math.floor(prand.length / 5);
  var mult = parseInt(prand.charAt(sPos) + prand.charAt(sPos*2) + prand.charAt(sPos*3) + prand.charAt(sPos*4) + prand.charAt(sPos*5));
  var incr = Math.ceil(pwd.length / 2);
  var modu = Math.pow(2, 31) - 1;
  if(mult < 2) {
    alert("Algorithm cannot find a suitable hash. Please choose a different password. \nPossible considerations are to choose a more complex or longer password.");
    return null;
  }
  var salt = Math.round(Math.random() * 1000000000) % 100000000;
  prand += salt;
  while(prand.length > 10) {
    prand = (parseInt(prand.substring(0, 10)) + parseInt(prand.substring(10, prand.length))).toString();
  }
  prand = (mult * prand + incr) % modu;
  var enc_chr = "";
  var enc_str = "";
  for(var i=0; i<str.length; i++) {
    enc_chr = parseInt(str.charCodeAt(i) ^ Math.floor((prand / modu) * 255));
    if(enc_chr < 16) {
      enc_str += "0" + enc_chr.toString(16);
    } else enc_str += enc_chr.toString(16);
    prand = (mult * prand + incr) % modu;
  }
  salt = salt.toString(16);
  while(salt.length < 8)salt = "0" + salt;
  enc_str += salt;
  return enc_str;
}

function decrypt(str, pwd) {
  if(str == null || str.length < 8) {
    alert("A salt value could not be extracted from the encrypted message because it's length is too short. The message cannot be decrypted.");
    return;
  }
  if(pwd == null || pwd.length <= 0) {
    alert("Please enter a password with which to decrypt the message.");
    return;
  }
  var prand = "";
  for(var i=0; i<pwd.length; i++) {
    prand += pwd.charCodeAt(i).toString();
  }
  var sPos = Math.floor(prand.length / 5);
  var mult = parseInt(prand.charAt(sPos) + prand.charAt(sPos*2) + prand.charAt(sPos*3) + prand.charAt(sPos*4) + prand.charAt(sPos*5));
  var incr = Math.round(pwd.length / 2);
  var modu = Math.pow(2, 31) - 1;
  var salt = parseInt(str.substring(str.length - 8, str.length), 16);
  str = str.substring(0, str.length - 8);
  prand += salt;
  while(prand.length > 10) {
    prand = (parseInt(prand.substring(0, 10)) + parseInt(prand.substring(10, prand.length))).toString();
  }
  prand = (mult * prand + incr) % modu;
  var enc_chr = "";
  var enc_str = "";
  for(var i=0; i<str.length; i+=2) {
    enc_chr = parseInt(parseInt(str.substring(i, i+2), 16) ^ Math.floor((prand / modu) * 255));
    enc_str += String.fromCharCode(enc_chr);
    prand = (mult * prand + incr) % modu;
  }
  return enc_str;
}

function changeMediaLink(pFormUrl)
{
    try
    {
		var arrSection=new Array();
		
		arrSection[arrSection.length]="leftcolumn";
		arrSection[arrSection.length]="innerpageleftcol";
		arrSection[arrSection.length]="rightcolumn";
		arrSection[arrSection.length]="single_column";
		
		var counter=0;
		var i=0;
		for(counter=0; counter<arrSection.length; counter++)
		{
			var section=document.getElementById(arrSection[counter]);
			//alert(section);
			if(section)
			{
				if(section.innerHTML.indexOf("/media/")>0)
				{
					var arrLinks=section.getElementsByTagName("a");
					
					for(i=0; i<arrLinks.length; i++)
					{
					    if (arrLinks[i].href.indexOf("/media/") > 0) {
					        var resource=arrLinks[i].href.split("/media/")[1];
					        if (gatedUrls.indexOf(resource) >= 0) {

					            //arrLinks[i].href = pFormUrl + "?rs=" + encrypt(arrLinks[i].href, 'password');
					            //alert(arrLinks[i].href);


					            arrLinks[i].href = pFormUrl + "?rs=" + gatedUrlIndex(resource);
					        }
					    }
					}
				}
			}
		}
    }
    catch(err)
    {
        alert(err.message);
    }
}

function gatedUrlIndex(resource) {
    var arrResources = gatedUrls.split("|");
    var i = 0;
    for (i = 0; i < arrResources.length; i++) {
        if (arrResources[i].indexOf(resource) > 0) {
            return i;
        }
    }
}

function changePFormSrc(pForm)
{
	var qs = window.location.search;
	if(qs.indexOf("?rs=")>=0)
	{
	    //var rs= decrypt(qs.split("=")[1], 'password')

	    var arrDomain = document.location.href.split("/");
	    var domain = arrDomain[0] + "/" + arrDomain[1] + "/" + arrDomain[2] + "/";
	    //alert(domain);

	    var rs = qs.split("=")[1];
	    if (rs != "") {
	        //alert(rs);
	        var arrIframe = document.getElementsByTagName("iframe");
	        var arrResources = gatedUrls.split("|");
	        var resourceUrl = domain + arrResources[rs * 1];
	        //alert(resourceUrl);
	        var i = 0;
	        for (i = 0; i < arrIframe.length; i++) {
	            if (arrIframe[0].src.indexOf(pForm) >= 0) {
	                //alert(arrIframe[0].src);
	                //arrIframe[0].src=arrIframe[0].src+"?rs="+rs;
	                arrIframe[0].src = arrIframe[0].src + "?rs=" + resourceUrl;
	                //alert(arrIframe[0].src);
	                break;
	            }
	        }
	    }
	}
}