/* 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.requestFile = file;
		this.vars = new Object();
		this.responseStatus = new Array(2);
		this.jsCode = null;
  	};

	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 (encode == true){
				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.jsCode);
	}

	this.runAJAX = function(urlstring) {
		if (this.failed) {
			this.onFail();
		}
		else {
			this.createURLString(urlstring);
			if (this.xmlhttp) {
				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) { }
				}
				var self = this;
				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:
							this.htmlArray = new Array();
							this.idArray = new Array();
//							this.responseArray = self.xmlhttp.responseText.split(/(<!--.*?-->)/);
							this.responseArray = split(self.xmlhttp.responseText, /(<!--.*?-->)/);
// 							trims leading empty string element made by split. Therefore delimiter MUST be the first thing in all responseTexts
							this.responseArray.shift();
							for (i = 0; i < this.responseArray.length; i++) {
								if (this.responseArray[i] != "") {
									if (this.responseArray[i].search(/<!--JS-->/) != -1) {
										self.jsCode = this.responseArray[i+1];
									}
									else if (this.responseArray[i].search(/<!--.*?-->/) != -1) {
										id_length = this.responseArray[i].length - 7;
										this.idArray.push(this.responseArray[i].substr(4, id_length));
										this.htmlArray.push(this.responseArray[i+1]);
										i++;
									}
									else {
										break;
									}
								}
							}

							self.responseXML = self.xmlhttp.responseXML;
							self.responseStatus[0] = self.xmlhttp.status;
							self.responseStatus[1] = self.xmlhttp.statusText;

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

							for (i = 0;  i < this.htmlArray.length; i++) {
								if (this.idArray[i].match(/\+/)) {
									this.idArray[i] = this.idArray[i].substr(0, this.idArray[i].length - 1)
									document.getElementById(this.idArray[i]).innerHTML += this.htmlArray[i];
								}
								else {
									document.getElementById(this.idArray[i]).innerHTML = this.htmlArray[i];
								}
							}

							if (self.responseStatus[0] == "200") {
								self.onCompletion();
								self.reset();
							} else {
								self.onError();
							}
							
							self.URLString = "";
							break;
					};
				};
				this.xmlhttp.send(this.URLString);
			}
		};
	};
	this.reset();
	this.createAJAX();
};