/* Initialize a Request object that is already constructed */
function initReq(request,reqType,url,bool,respHandle){
    try{
        /* Specify the function that will handle the HTTP response */
        request.onreadystatechange=respHandle;
        request.open(reqType,url,bool);
        //if the reqType parameter is POST, then the
        //5th argument to the function is the POSTed data
        if(reqType.toLowerCase() == "post") {
            request.setRequestHeader("Content-Type",
                        "application/x-www-form-urlencoded; charset=UTF-8");
            request.send(arguments[5]);
        }   else {
            request.send(null);
        }

    } catch (errv) {
    }
}

/* Wrapper function for constructing a Request object.
 Parameters:
  reqType: The HTTP request type such as GET or POST.
  url: The URL of the server program.
  asynch: Whether to send the request asynchronously or not.
  respHandle: The name of the function that will handle the response.
  Any fifth parameters represented as arguments[4] are the data a
  POST request is designed to send. */

function initHttpRequest(){
    //Mozilla-based browsers
    var request = null;
    if(window.XMLHttpRequest){
        request = new XMLHttpRequest();
    } else if (window.ActiveXObject){
        request=new ActiveXObject("Msxml2.XMLHTTP");
        if (! request){
            request=new ActiveXObject("Microsoft.XMLHTTP");
        }
    }
    return request;
}

function httpRequest(request,reqType,url,asynch,respHandle){
    //Very unlikely, but we test for a null request
    //if neither ActiveXObject was initialized
    if(request)  {
        //if the reqType parameter is POST, then the
        //5th argument to the function is the POSTed data
        if(reqType.toLowerCase() != "post") {
            initReq(request,reqType,url,asynch,respHandle);
        }  else {
            //the POSTed data
            var args = arguments[5];
            if(args != null && args.length > 0){
                initReq(request,reqType,url,asynch,respHandle,args);
            }
        }
    }  else {
              }
}

function getDomAdapter()
{
	var adapter = '';
	if ('undefined' != typeof ActiveXObject) {
		adapter = 'MS';
	} else if ('undefined' != typeof document
		&& document.implementation
		&& document.implementation.createDocument
		&& 'undefined' != typeof DOMParser)
	{
		adapter = 'default';
	}
	switch (adapter) {
		case 'MS':
			return new (function () {
				this.createDocument = function () {
					var names = ["Msxml2.DOMDocument.6.0",
						"Msxml2.DOMDocument.3.0", "MSXML2.DOMDocument",
						"MSXML.DOMDocument", "Microsoft.XMLDOM"];
					for (var key in names) {
						try {
							return new ActiveXObject(names[key]);
						} catch (e) {}
					}
					throw new Error('Unable to create DOMDocument');
				};
				this.serialize = function (doc) {
					return doc.xml;
				};
				this.parseXml = function (xml) {
					var doc = this.createDocument();
					if (!doc.loadXML(xml)) {
						throw new Error('Parse error');
					}
					return doc;
				};
			})();
		case 'default':
			return new (function () {
				this.createDocument = function () {
					return document.implementation.createDocument("", "", null);
				};
				this.serialize = function (doc) {
					return new XMLSerializer().serializeToString(doc);
				};
				this.parseXml = function (xml) {
					var doc = new DOMParser().parseFromString(xml, "text/xml");
					if ("parsererror" == doc.documentElement.nodeName) {
						throw new Error('Parse error');
					}
					return doc;
				};
			})();
		default:
			throw new Error('Unable to select the DOM adapter');
	}
};