function HttpReq() {
    this.action = null;
    this.XML = null;
    this.httpInterface = null;

    // Initialise XMLHttpRequest object
    this.resetInterface();

    return true;
}

/* Check if the HttpReq object is available */
HttpReq.prototype.isAvailable = function() {
    if (this.httpInterface == null) {
        return false;
    }

    return true;
}

/* Execute the action which has been associated with the completion of this object */
HttpReq.prototype.executeAction = function() {
    // If XMLHR object has finished retrieving the data
    if (this.httpInterface.readyState == 4) {
        // If the data was retrieved successfully
        try {
            if (this.httpInterface.status == 200) {
                this.action();
            }
            // IE returns status = 0 on some occasions, so ignore
            else if (this.httpInterface.status != 0) {
                //alert("There was an error while retrieving the URL: " + this.httpInterface.statusText);
            }
        }
        catch (error) {
        }
    }

    return true;
}

/* Return responseText */
HttpReq.prototype.getText = function() {
    return this.httpInterface.responseText;
}

/* Return responseXML */
HttpReq.prototype.getXML = function() {
    return this.httpInterface.responseXML;
}

/* Initialise object and load URL */
HttpReq.prototype.loadURL = function(url, cgi) {
    this.resetInterface();
    var url2;

    if (cgi != null) {
        url2 = url + "?" + cgi;
    }
    else {
        url2 = url;
    }

    //alert(url);
    this.httpInterface.open("GET", url2);
    this.httpInterface.send(null);

    return true;
}

/* Turn off existing connections and create a new XMLHR object */
HttpReq.prototype.resetInterface = function() {
    var self = this;

    if (this.httpInterface != null && this.httpInterface.readyState != 0 && this.httpInterface.readyState != 4) {
        this.httpInterface.abort();
    }

    this.httpInterface = getHttpObj();

    this.httpInterface.onreadystatechange = function() {
        self.executeAction();

        return true;
    };

    return true;
}

/* Assign the function which will be executed once the XMLHR object finishes retrieving data */
HttpReq.prototype.setAction = function(actionFunction) {
    this.action = actionFunction;

    return true;
}

function getHttpObj() {
    var httpObj = null;
    try {
        httpObj = new ActiveXObject("Microsoft.XMLHTTP");
    }
    catch (error) {
        try {
            httpObj = new XMLHttpRequest();
        }
        catch (error) {
            httpObj = null;
        }
    }

    return httpObj;
}

function loadSyncHttp(url, cgi) {
    var httpReq = getHttpObj();
    var response = null;
    var url = url + "?" + cgi;

    if (null != httpReq) {
        //alert("Calling url:" + url);
        httpReq.open("GET", url, false);
        httpReq.send(null);

        if (httpReq.status == 200)
            response = httpReq.responseText;
    }

    return response;
}

function loadSyncHttpXML(url, cgi) {
    var httpReq = getHttpObj();
    var response = null;

    if (null != httpReq) {
        httpReq.open("GET", url + "?" + cgi, false);
        httpReq.send(null);
    }
    if (httpReq.status == 200)
        response = httpReq.responseXML;

    return response;
}

function htmlEncode(s) {
    var str = new String(s);
    str = str.replace(/&/g, "&");
    str = str.replace(/</g, "&#60;");
    str = str.replace(/>/g, "&#62;");
    str = str.replace(/"/g, "&#34;");
    str = str.replace(/'/g, "&#39;");

    return str;
}

function evaluate(res) {
    if (res.length > 0) {
        try {
            return eval(res);
        }
        catch (error) {
            //alert(error);
        }
    }
}

function evaluateObjectEqual(res) {
    var obj = null;
    if (res.length > 0) {
        try {
            res = "obj = " + res;
            eval(res);
        }
        catch (error) {
            obj = null;
            // alert(error.message);
        }
    }

    return obj;
}

function parseJson(text, filter) {
    var j;

    function walk(k, v) {
        var i;
        if (v && typeof v === 'object') {
            for (i in v) {
                if (Object.prototype.hasOwnProperty.apply(v, [i])) {
                    v[i] = walk(i, v[i]);
                }
            }
        }
        return filter(k, v);
    }

    if (/^[,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]*$/.test(text.
            replace(/\\./g, '@').
            replace(/"[^"\\\n\r]*"/g, ''))) {
        writeLine("start eval: " + (new Date()));
        j = eval('(' + text + ')');
        writeLine("end eval: " + (new Date()));
        return typeof filter === 'function' ? walk('', j) : j;
    }

    throw new SyntaxError('parseJSON');
}

function addOnLoad(newOnLoad) {
    var curOnLoad = window.onload;
    if (typeof window.onload != "function") {
        window.onload = newOnLoad;
    }
    else {
        window.onload = function() {
            curOnLoad();
            newOnLoad();
        }
    }
}

function addOnUnload(newOnUnload) {
    var curOnUnload = window.onunload;
    if (typeof window.onunload != "function") {
        window.onunload = newOnUnload;
    }
    else {
        window.onunload = function() {
            curOnUnload();
            newOnUnload();
        }
    }
}

function StringBuilder(value) {
    this.strings = new Array("");
    this.append(value);
}

StringBuilder.prototype.append = function(value) {
    if (value) {
        this.strings.push(value);
    }
}

StringBuilder.prototype.clear = function() {
    this.strings.length = 1;
}

StringBuilder.prototype.toString = function() {
    return this.strings.join("");
}