/**
 * Internal function to remove content from the main area and add the notebook.
 * Not idempotent
 */
function append_notebook(url){
    clear_main_area();
    $('#main').append('<iframe frameBorder="0" seamless="seamless" style="width: 100%; height: 100%; overflow:hidden;" scrolling="no" src="'+ url +'"></iframe>'
    );
}

function clear_main_area(){
    $('#spinner').remove();
    $('#main').children().remove();
}

function display_spinner(){
        $('#main').append('<img id="spinner" src="' + galaxy_root + '/static/style/largespinner.gif" style="position:absolute;margin:auto;top:0;left:0;right:0;bottom:0;">');
}


/**
 * Test availability of a URL, and call a callback when done.
 * http://stackoverflow.com/q/25390206/347368
 * @param {String} url: URL to test availability of. Must return a 200 (302->200 is OK).
 * @param {String} callback: function to call once successfully connected.
 *
 */
function test_ie_availability(url, success_callback){
    var request_count = 0;
    display_spinner();
    interval = setInterval(function(){
        $.ajax({
            url: url,
            xhrFields: {
                withCredentials: true
            },
            type: "GET",
            timeout: 500,
            success: function(){
                console.log("Connected to IE, returning");
                clearInterval(interval);
                success_callback();
            },
            error: function(jqxhr, status, error){
                request_count++;
                console.log("Request " + request_count);
                if(request_count > 30){
                    clearInterval(interval);
                    clear_main_area();
                    toastr.error(
                        "Could not connect to IE, contact your administrator",
                        "Error",
                        {'closeButton': true, 'timeOut': 20000, 'tapToDismiss': false}
                    );
                }
            }
        });
    }, 1000);
}