small javascript library for ajax & some other things

gcf.js

// variable to en-/disable debug
// set to 1 to enable debug log
if (DEBUG === undefined) {
    var DEBUG;
}



var gcf = {


    // decode special characters with their utf-8 representation
    decodeHtml : function (token) {

        var i,
            y,
            start = [33, 58, 91, 123, 161],
            stop = [47, 64, 96, 126, 255],
            startLength = start.length;

        for (y = 0; y < startLength; y++) {
            for (i = start[y]; i <= stop[y]; i++) {
                token = token.replace("&#" + i +";", String.fromCharCode(255));
            }
        }

        return token;
    },


    // get the path of the cgi-bin dir with correct http(s) protocol
    // for using with ajax calls (to with same origin policy)
    getCgiBinPath : function () {

        // parse actual url and parse for protocol type (http/https)
        // set the ajax server url dependent on the protocol
        // for strato ssl-proxy, we have to insert the 1st part of the url path
        var serverUrl = window.location.protocol + "//" +  window.location.hostname;

        if (serverUrl.indexOf("https") === -1) {
            serverUrl += "/cgi-bin/";
        } else {
            serverUrl += "/" + window.location.pathname.split("/")[1] + "/cgi-bin/";
        }

        return serverUrl;

    },


    // xmlhttp object function
    getHTTPObject : function () {

        // debug log
        if (DEBUG === 1) {console.log("xml http object function");}

        // variable definitions
        var xhr;

        // check for availibility if xmlhttprequest object
        if(window.XMLHttpRequest) {
            xhr = new XMLHttpRequest();
        } else if(window.ActiveXObject) {
            xhr = new ActiveXObject("Msxml2.XMLHTTP");
        }

        return xhr;

    },


    // ajax call function
    ajaxCall : function (dataUrl, outputElement, callback, responseType) {

        // debug log
        if (DEBUG === 1) {console.log("ajax function");}

        // variable definitions
        var response,
            request = this.getHTTPObject();  // get the xmlhttp object which is supported

        outputElement.innerHTML = "Lade Daten ...";

        request.onreadystatechange = function() {

            if(request.readyState === 4 && request.status === 200) {

                //save ajax response
                if (responseType === "json") {
                    response = JSON.parse(request.responseText);
                } else if (responseType === "xml") {
                    response = request.responseXML;
                } else {
                    response = request.responseText;
                }

                // check if callback is a function
                if(typeof callback === "function") {
                    callback(response);
                } else {
                    if (DEBUG === 1) {console.log(callback + " is no callback function");}
                }
            }
        };

        request.open("get", dataUrl, true);
        request.send(null);

    }


};