/* Simple AJAX Code-Kit (SACK) v1.6.1 */
/* ©2005 Gregory Wild-Smith */
/* www.twilightuniverse.com */

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();
  };

  this.createAJAX = function() {
    try {
      this.xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e1) {
      try {
        this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
      } 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();
}