var _ms_XMLHttpRequest_ActiveX = ""; // Holds type of ActiveX to instantiate
var _ajax;                           // Reference to a global XMLHTTPRequest object for some of the samples
var _status_area;                    // will point to the area to write status messages to

if (!window.Node || !window.Node.ELEMENT_NODE) {
    var Node = { ELEMENT_NODE: 1, ATTRIBUTE_NODE: 2, TEXT_NODE: 3, CDATA_SECTION_NODE: 4, ENTITY_REFERENCE_NODE: 5,
                  ENTITY_NODE: 6, PROCESSING_INSTRUCTION_NODE: 7, COMMENT_NODE: 8, DOCUMENT_NODE: 9, DOCUMENT_TYPE_NODE: 10, 
    		  DOCUMENT_FRAGMENT_NODE: 11, NOTATION_NODE: 12 };
}

// From prototype.js @ www.conio.net | Returns an object reference to one or more strings
// ignore the fact that there are no arguments to this method -- javascript doesn't care how many you send (not strongly typed)
// The method checks the actual # of arguments -- returns a single object or an array
function $() {
    var elements = new Array();

    for (var i = 0; i < arguments.length; i++) {
        var element = arguments[i];

        if (typeof element == 'string')
            element = document.getElementById(element);

        if (arguments.length == 1)
            return element;

        elements.push(element);
    }

    return elements;
}

function encode( uri ) {
    if (encodeURIComponent) {
        return encodeURIComponent(uri);
    }

    if (escape) {
        return escape(uri);
    }
}

function decode( uri ) {
    uri = uri.replace(/\+/g, ' ');

    if (decodeURIComponent) {
        return decodeURIComponent(uri);
    }

    if (unescape) {
        return unescape(uri);
    }

    return uri;
}

/*
 * AJAXRequest: An encapsulated AJAX request. To run, call
 * new AJAXRequest( method, url, async, process, data )
 *
 */

function executeReturn( AJAX ) {
    if (AJAX.readyState == 4) {
        if (AJAX.status == 200) {
	    if ( AJAX.responseText ) {
		    eval(AJAX.responseText);
	    }
	}
    }
}

function AJAXRequest( method, url, data, process, async, dosend) {
    // self = this; creates a pointer to the current function
    // the pointer will be used to create a "closure". A closure
    // allows a subordinate function to contain an object reference to the
    // calling function. We can't just use "this" because in our anonymous
    // function later, "this" will refer to the object that calls the function 
    // during runtime, not the AJAXRequest function that is declaring the function
    // clear as mud, right?
    // Java this ain't
    
    var self = this;

    // check the dom to see if this is IE or not
    if (window.XMLHttpRequest) {
	// Not IE
        self.AJAX = new XMLHttpRequest();
    } else if (window.ActiveXObject) {
	// Hello IE!
        // Instantiate the latest MS ActiveX Objects
        if (_ms_XMLHttpRequest_ActiveX) {
            self.AJAX = new ActiveXObject(_ms_XMLHttpRequest_ActiveX);
        } else {
	    // loops through the various versions of XMLHTTP to ensure we're using the latest
	    var versions = ["Msxml2.XMLHTTP.7.0", "Msxml2.XMLHTTP.6.0", "Msxml2.XMLHTTP.5.0", "Msxml2.XMLHTTP.4.0", "MSXML2.XMLHTTP.3.0", "MSXML2.XMLHTTP",
                        "Microsoft.XMLHTTP"];

            for (var i = 0; i < versions.length ; i++) {
                try {
		    // try to create the object
		    // if it doesn't work, we'll try again
		    // if it does work, we'll save a reference to the proper one to speed up future instantiations
                    self.AJAX = new ActiveXObject(versions[i]);

                    if (self.AJAX) {
                        _ms_XMLHttpRequest_ActiveX = versions[i];
                        break;
                    }
                }
                catch (objException) {
                // trap; try next one
                } ;
            }

            ;
        }
    }
	
	if (process === false) {
		process = doNothing;
	}
    
    // if no callback process is specified, then assing a default which executes the code returned by the server
    if (typeof process == 'undefined' || process == null) {
        process = executeReturn;
    }

    self.process = process;

    // create an anonymous function to log state changes
    self.AJAX.onreadystatechange = function( ) {
        self.process(self.AJAX);
    }

    // if no method specified, then default to POST
    if (!method) {
        method = "POST";
    }

    method = method.toUpperCase();

    if (typeof async == 'undefined' || async == null) {
        async = true;
    }

    self.AJAX.open(method, url, async);

    if (method == "POST") {
        self.AJAX.setRequestHeader("Connection", "close");
        self.AJAX.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
        self.AJAX.setRequestHeader("Method", "POST " + url + "HTTP/1.1");
    }

    // if dosend is true or undefined, send the request
    // only fails is dosend is false
    // you'd do this to set special request headers
    if ( dosend || typeof dosend == 'undefined' ) {
	    if ( !data ) data=""; 
	    self.AJAX.send(data);
    }
    return self.AJAX;
}

function doNothing(myAJAX) {
	return true;
}