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.kell_kesz = true;
	};

	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() {
		if (window.XMLHttpRequest) {
			this.xmlhttp = new XMLHttpRequest();
		} else {
			try {
				this.xmlhttp  = new ActiveXObject('Msxml2.XMLHTTP');
			} catch(e) {
				try {
					this.xmlhttp  = new ActiveXObject('Microsoft.XMLHTTP');
				} catch (e) {
					alert("nincs ajax");
				}
			}
		}
	};

	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.kesz = function(obj) {
		//alert("kesz fuggveny");
		obj.kell_kesz=false;
		obj.response = obj.xmlhttp.responseText;
		obj.responseXML = obj.xmlhttp.responseXML;
		obj.responseStatus[0] = obj.xmlhttp.status;
		obj.responseStatus[1] = obj.xmlhttp.statusText;

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

		if (obj.elementObj) {
			elemNodeName = obj.elementObj.nodeName;
			elemNodeName.toLowerCase();
			if (elemNodeName == "input"
			|| elemNodeName == "select"
			|| elemNodeName == "option"
			|| elemNodeName == "textarea") {
				obj.elementObj.value = obj.response;
			} else {
				obj.elementObj.innerHTML = obj.response;
			}
		}
		if (obj.responseStatus[0] == "200") {
			obj.onCompletion();
		} else {
			obj.onError();
		}

		obj.URLString = "";
	}


	this.runAJAX = function(urlstring, async) {
		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, async);
				} else {
					this.xmlhttp.open(this.method, this.requestFile, async);
					try {
						this.xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded")
					} catch (e) { }
				}

				this.xmlhttp.onreadystatechange = function() {
					//alert("onreadystatechange");
					switch (self.xmlhttp.readyState) {
						case 1:
						//alert(" 1 onLoading");
						self.onLoading();
						break;
						case 2:
						//alert(" 2 onLoaded");
						self.onLoaded();
						break;
						case 3:
						//alert(" 3 onInteractive");
						self.onInteractive();
						break;
						case 4:
						//alert("4 kesz jon: async");
						self.kesz(self);
						break;
					}
				};
				//alert("send before");
				this.xmlhttp.send(this.URLString);
				//alert("send after");
				if(!async && this.kell_kesz){
					//alert("kesz jon: nem async");
					this.kesz(self);
				}
			}
		}
	};

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