/* 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(response) { };
  		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");
						this.xmlhttp.setRequestHeader("X-Requested-With", "XMLHttpRequest");
					} 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(self.response);
							} else {
								self.onError();
							}

							self.URLString = "";
							/* These lines were added by Alf Magne Kalleland ref. info on the sack home page. It prevents memory leakage in IE */

							delete self.xmlhttp['onreadystatechange'];
							self.xmlhttp=null;
							self.responseStatus=null;
							self.response=null;
							self.responseXML=null;
														
							break;
					}
				};

				this.xmlhttp.send(this.URLString);
			}
		};
	};
		
	this.serializeForm=function(options) {
			var defaultOptions={formObject:document.forms[0],encodeValues:false,includeEmptyValues:false};
			for( var opt in options )
			{
				defaultOptions[opt]=options[opt];
			}
			if( !defaultOptions.formObject )
				return null;
	 
			var f=defaultOptions.formObject;
			defaultOptions.encodeValues = defaultOptions.encodeValues ? encodeURIComponent : function(str){return str;};
	 
			var params = {};
			for( var i=0, limit=f.elements.length; i < limit; ++i)
			{
				if( defaultOptions.includeEmptyValues==false && f.elements[i].value=="" )
				{
					continue;
				}
				var key=null;
				switch( String(f.elements[i].type).toUpperCase() )
				{
					case "TEXT":
					case "SUBMIT":
					case "HIDDEN":
					case "PASSWORD":
						key=f.elements[i].name;
						break;
	 
					case "CHECKBOX":
					case "RADIO":
						if( f.elements[i].checked )
						{
							key=f.elements[i].name;
						}
						break;
	 
					default:
						switch( String(f.elements[i].tagName).toUpperCase() )
						{
							case "TEXTAREA":
							case "SELECT":
								key=f.elements[i].name;
							break;
						}
						break;
				}
				if( key )
				{
					if( typeof(params[key]) === "undefined" )
					{
						params[key]=defaultOptions.encodeValues(f.elements[i].value);
					}
					else
					{
						if("string"==typeof(params[key]))
						{
							var temp = params[key];
							params[key]= new Array(temp);
						}
						params[key].push( defaultOptions.encodeValues(f.elements[i].value) );
					}
				}
			}
	 
			for( var fieldName in params )
			{
				if( typeof(params[fieldName]) =="string" )
				{
					this.setVar(fieldName , params[fieldName] );
				}
				else
				{
					for( var i =0,limit=params[fieldName].length; i < limit; ++i)
					{
						this.setVar(fieldName,params[fieldName][i]);
					}
				}
			}
		return params;
		
	};

	this.reset();
	this.createAJAX();
}