/* 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();
       };

       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();
}