/* Simple AJAX Code-Kit (SACK) v1.6.1 */
/* 2005 Gregory Wild-Smith */
/* www.twilightuniverse.com */
/* Software licenced under a modified X11 licence,
   see documentation or authors website for more details */

function sack(file)
{
  this.xmlhttp = null;

  this.resetData = function()
  {
    this.method = "POST";
    this.queryStringSeparator = "?";
    this.argumentSeparator = "&";
    this.URLString = "";
    this.encodeURIString = true;
    this.execute = false;
    this.element = null;
    this.elementObj = null;
    this.requestFile = file;
    this.vars = new Object();
    this.responseStatus = new Array(2);
  };

  this.resetFunctions = function()
  {
    this.onLoading = function() { };
    this.onLoaded = function() { };
    this.onInteractive = function() { };
    this.onCompletion = function() { };
    this.onError = function() { };
    this.onFail = function() { };
  };

  this.reset = function()
  {
    this.resetFunctions();
    this.resetData();
  };


  var req;

  if(window.XMLHttpRequest)
  {
    //For Firefox, Safari, Opera
    req = new XMLHttpRequest();
  }
  else if(window.ActiveXObject)
  {
    //For IE 5
    req = new ActiveXObject("Microsoft.XMLHTTP");
  }
  else if(window.ActiveXObject)
  {
    //For IE 6+
    req = new ActiveXObject("Msxml2.XMLHTTP");
  }
  else
  {
    //Error for an old browser
    alert('Your browser is not IE 5 or higher, or Firefox or Safari or Opera');
  }


  this.createAJAX = function()
  {
    try
    {
      //this.xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
      // this insures it works in all browsers
      // JT -- added 6-24-09
      if(window.XMLHttpRequest)
      {
        //For Firefox, Safari, Opera
        this.xmlhttp = new XMLHttpRequest();
      }
      else if(window.ActiveXObject)
      {
        //For IE 5
        this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
      }
      else if(window.ActiveXObject)
      {
        //For IE 6+
        this.xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
      }
      else
      {
        //Error for an old browser
        alert('Your browser is not IE 5 or higher, or Firefox or Safari or Opera');
      }
    }
    catch (e1)
    {
      try
      {
        //this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        // this insures it works in all browsers
        // JT -- added 6-24-09
        if(window.XMLHttpRequest)
        {
          //For Firefox, Safari, Opera
          this.xmlhttp = new XMLHttpRequest();
        }
        else if(window.ActiveXObject)
        {
          //For IE 5
          this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }
        else if(window.ActiveXObject)
        {
          //For IE 6+
          this.xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
        }
        else
        {
          //Error for an old browser
          alert('Your browser is not IE 5 or higher, or Firefox or Safari or Opera');
        }
      }
      catch (e2)
      {
        this.xmlhttp = null;
      }
    }

    if (! this.xmlhttp)
    {
      if (typeof XMLHttpRequest != "undefined")
      {
        this.xmlhttp = new XMLHttpRequest();
      }
      else
      {
        this.failed = true;
      }
    }
  };

  this.setVar = function(name, value)
  {
    this.vars[name] = Array(value, false);
  };

  this.encVar = function(name, value, returnvars)
  {
    if (true == returnvars)
    {
      return Array(encodeURIComponent(name), encodeURIComponent(value));
    }
    else
    {
      this.vars[encodeURIComponent(name)] = Array(encodeURIComponent(value), true);
    }
  }

  this.processURLString = function(string, encode)
  {
    encoded = encodeURIComponent(this.argumentSeparator);
    regexp = new RegExp(this.argumentSeparator + "|" + encoded);
    varArray = string.split(regexp);
    for (i = 0; i < varArray.length; i++)
    {
      urlVars = varArray[i].split("=");
      if (true == encode)
      {
        this.encVar(urlVars[0], urlVars[1]);
      }
      else
      {
        this.setVar(urlVars[0], urlVars[1]);
      }
    }
  }

  this.createURLString = function(urlstring)
  {
    if (this.encodeURIString && this.URLString.length)
    {
      this.processURLString(this.URLString, true);
    }

    if (urlstring)
    {
      if (this.URLString.length)
      {
        this.URLString += this.argumentSeparator + urlstring;
      }
      else
      {
        this.URLString = urlstring;
      }
    }

    // prevents caching of URLString
    this.setVar("rndval", new Date().getTime());

    urlstringtemp = new Array();
    for (key in this.vars)
    {
      if (false == this.vars[key][1] && true == this.encodeURIString)
      {
        encoded = this.encVar(key, this.vars[key][0], true);
        delete this.vars[key];
        this.vars[encoded[0]] = Array(encoded[1], true);
        key = encoded[0];
      }
      urlstringtemp[urlstringtemp.length] = key + "=" + this.vars[key][0];
    }
    if (urlstring)
    {
      this.URLString += this.argumentSeparator + urlstringtemp.join(this.argumentSeparator);
    }
    else
    {
      this.URLString += urlstringtemp.join(this.argumentSeparator);
    }
  }

  this.runResponse = function()
  {
    eval(this.response);
  }

  this.runAJAX = function(urlstring)
  {
    if (this.failed)
    {
      this.onFail();
    }
    else
    {
      this.createURLString(urlstring);
      if (this.element)
      {
        this.elementObj = document.getElementById(this.element);
      }
      if (this.xmlhttp)
      {
        var self = this;
        if (this.method == "GET")
        {
          totalurlstring = this.requestFile + this.queryStringSeparator + this.URLString;
          this.xmlhttp.open(this.method, totalurlstring, true);
        }
        else
        {
          this.xmlhttp.open(this.method, this.requestFile, true);
          try
          {
            this.xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded")
          }
          catch (e) { }
        }

        this.xmlhttp.onreadystatechange = function()
        {
          switch (self.xmlhttp.readyState)
          {
            case 1:
              self.onLoading();
              break;
            case 2:
              self.onLoaded();
              break;
            case 3:
              self.onInteractive();
              break;
            case 4:
              self.response = self.xmlhttp.responseText;
              self.responseXML = self.xmlhttp.responseXML;
              self.responseStatus[0] = self.xmlhttp.status;
              self.responseStatus[1] = self.xmlhttp.statusText;

              if (self.execute)
              {
                self.runResponse();
              }

              if (self.elementObj)
              {
                elemNodeName = self.elementObj.nodeName;
                elemNodeName.toLowerCase();
                if (elemNodeName == "input" || elemNodeName == "select" || elemNodeName == "option" || elemNodeName == "textarea")
                {
                  self.elementObj.value = self.response;
                }
                else
                {
                  self.elementObj.innerHTML = self.response;
                }
              }
              if (self.responseStatus[0] == "200")
              {
                self.onCompletion();
              }
              else
              {
                self.onError();
              }
              self.URLString = "";
              break;
          }
        };
        this.xmlhttp.send(this.URLString);
      }
    }
  };
  this.reset();
  this.createAJAX();
}