/* 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 */

/*
Note: This is a modified version of the X11 Licence (commonly known as the MIT licence). The modifications relate to including not only the copyright notice, as per the original X11, but also the authors URL. This is a trivial modification, and does not affect any other part of the licence.
COPYRIGHT AND PERMISSION NOTICE for Simple AJAX Code Kit (SACK).

Copyright © 2005 Gregory Wild-Smith
Authors Website: http://www.twilightuniverse.com/

All rights reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, provided that the above copyright notice(s), authors website url, and this permission notice appear in all copies of the Software and that the above copyright notice(s), authors url, and this permission notice appear in supporting documentation.
*/

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();
}