<?
//
// FAPWeb Simple Demoparty System
// Common AJAX Javascript code module
// (C) Copyright 2012-2013 Tecnic Software productions (TNSP)
//


function stCommonAJAX($backend, $failover, $script = FALSE)
{
if ($script)
  echo "<script type=\"text/javascript\">\n";

?>
function statusMsg(msg)
{
  document.getElementById("nstatus").innerHTML = msg;
}


function strtrim(str)
{
  if (!str || str == null)
    return "";
  return str.replace(/^\s+|\s+$/g,'')
}


function strencode(str)
{
  return encodeURIComponent(str);
}


function createXMLRequest()
{
  var req;
  if (window.XMLHttpRequest)
  {
    // Modern browsers
    req = new XMLHttpRequest();
  }
  else
  {
    // Old IE versions
    req = new ActiveXObject("Microsoft.XMLHTTP");
  }
  return req;
}


function sendPOSTRequest(params, success, failure)
{
  var req = createXMLRequest();
  req.open("POST", "<? echo $backend ?>", true);
  req.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
  req.setRequestHeader("Content-length", params.length);
  req.setRequestHeader("Connection", "close");

  req.onreadystatechange = function()
  {
    if (req.readyState == 4)
    {
      if (req.status == 404)
      {
        window.location = "<? echo $failover ?>";
      }
      else
      if (req.status == 902)
      {
        statusMsg(req.statusText);
        alert(req.responseText);
      }
      else
      if (req.status == 200)
      {
        if (success)
        {
          success(req.responseText);
        }
        statusMsg(req.statusText);
      }
      else
      {
        if (failure)
        {
          failure(req.status, req.statusText, req.responseText);
        }
        else
        {
          statusMsg("["+req.status+" - "+req.statusText+"] "+ req.responseText);
        }
      }
    }
  }
  req.send(params);
}


//
// Function for creating AJAX POST request arguments list based
// on fields and giving them specified types. Also basic check
// for validity can be performed (e.g. field empty or not)
//
function makePostArgs(fields, fprefix, fsuffix)
{
  var res = [];
  for (var id in fields)
  {
    var elem = document.getElementById(fprefix + id + fsuffix);
    if (!elem)
    {
      alert("No such DOM element '"+ fprefix + id + fsuffix +"'.");
      return "";
    }

    switch (fields[id])
    {
      case 0:
      case 1:
      case 4:
        {
          var str = strtrim(elem.value);
          if ((fields[id] == 1 || fields[id] == 4) && str == "")
          {
            alert("One or more of the required fields are empty.");
            return "";
          }
          if (fields[id] == 4)
            res.push(id+"="+parseInt(elem.value));
          else
            res.push(id+"="+strencode(str));
        }
        break;

      case 2:
        res.push(id+"="+parseInt(elem.value));
        break;

      case 3:
        res.push(id+"="+(elem.checked ? "1" : "0"));
        break;

    }
  }
  return res.join("&");
}
<?
if ($script)
  echo "</script>\n";
}
?>