function fireTimer(obj) {
    var myObj = obj;
    function timerFired() {
        if (myObj.inprogress){myObj._abortRequest(myObj);}
    }
    myObj._timeoutID = window.setTimeout(timerFired, myObj.timeoutMS);
}

function HTTPXml(){};

HTTPXml.prototype = {
    uservars: null,
    url: null,
    postbuffer: null,
    xmlhttp: null,
    inprogress: false,
    thecallback: null,
    ref:null,
    timeoutMS: -1,
    _timeoutID: null,
    cancelled: false,
    init: function(url, postbuffer, args) {
        this.url = url;
        this.uservars = args;
        this.postbuffer = postbuffer;
        if (window.XMLHttpRequest) {
            this.xmlhttp = new XMLHttpRequest();
        } else if (window.ActiveXObject) {
            this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        } else {
            window.alert('Sorry your browser is not compatible with this functionality');
        }
    },
    setTimeout: function(timeInMillisec) {
        this.timeoutMS = timeInMillisec;
    },
    asyncGET: function (client) {
        if (this.inprogress) {
            throw "Call in progress";
        };
        var self = this;
        if (client==null) {client=self;}
        this.thecallback = client;
        var args = null;
        if (this.postbuffer == null) {
            this.xmlhttp.open('GET',this.url,true);
        } else {
            this.xmlhttp.open("POST", this.url, true);
            this.xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=ISO-8859-1");
            args = this.postbuffer;
        }
        this.xmlhttp.onreadystatechange = function() {
            self.stateChangeCallback(self);
        }
        this.inprogress = true;
        this.cancelled = false;
        this.xmlhttp.send(args);
        if (this.timeoutMS > 0) {
            fireTimer(this);
        }
    },
    stateChangeCallback: function(client) {
        switch (client.xmlhttp.readyState) 
        {
            case 1:
                try {
                    if (! client.cancelled) {
                        client.thecallback.onInit();
                    }
                } catch (e) {  }
            break;
            case 2:
                try {
                    
                    if ( client.xmlhttp.status != 200 ) {
                        if (! client.cancelled) {
                        window.status="error";
                        client.thecallback.onError(
                            client.xmlhttp.status,
                            client.xmlhttp.statusText,
                            client
                            );
                        }
                        client.xmlhttp.abort();
                        client.inprogress = false;
                    }
                  }
                catch (e) {}
            break;
            case 3:
                var contentLength;
                try {
                    try {
                        contentLength =
                            client.xmlhttp.getResponseHeader("Content-Length");
                    } catch (e) {
                        contentLength = NaN;
                    }
                    if (! client.cancelled) {
                        window.status="ping";
                        client.thecallback.onProgress(
                            client.xmlhttp.responseText,
                            contentLength);
                    }

                } catch (e) {  }
            break;
            case 4:
                try {
                    if (client._timeoutID) {
                        window.clearTimeout(client._timeoutID);
                        client._timeoutID = null;
                    }
                    
                    if (client.inprogress) {
                        client.inprogress = false;
                        if (! client.cancelled) {
                            window.status="done";
                            client.thecallback.onLoad(client);
                        }
                    }
                } catch (e) {
                    
                } finally {
                    client.inprogress = false;
                }
            break;
        }
    },
    cancelRequest: function() {
        var gizmo = this;
        this.cancelled = true;
        if (this._timeoutID) {
            window.clearTimeout(this._timeoutID);
            this._timeoutID = null;
        }
        gizmo._abortRequest(gizmo);
    },
    _abortRequest: function(gizmo) {
        if (gizmo.xmlhttp!=null) {
            try {
                gizmo.xmlhttp.abort();
                if (gizmo.inprogress){
                    window.status="abort";
                    gizmo.thecallback.onError('timeout', 'Your request has timed out.',gizmo);
                }
            } catch (e) {}
            gizmo.cancelled = true;
            gizmo.inprogress = false;
        }
    },
    getText: function () {
        return this.xmlhttp.responseText;
    },
    getXML: function () {
        return this.xmlhttp.responseXML;
    },
    getTags: function (tagname) {
        try {
            return this.xmlhttp.responseXML.getElementsByTagName(tagname);
        } catch (e) {return null;}
    },
    getTagsByItem: function (parent,item,index)
    {
        var result = parent.getElementsByTagName(item)[index];
        if (result)
        {
          return result;
        }
        else { return ""; }
    },    
    getTagText: function (parent,item)
    {
        var result = parent.getElementsByTagName(item)[0];
        if (result)
        {
              if (result.firstChild)
                return result.firstChild.nodeValue;
              else
                return result.text;
        }
        else { return ""; }
    },
    getTagAttr: function (parent,item)
    {
        var result = parent;
        if (result)
        {
                return result.getAttribute(item); 
        }
        else { return ""; }
    },    
    onProgress:function(t,l){},
    onError:function(s,t,c){},
    onLoad:function(c) { },
    onInit:function(c) { }
}