function refreshCalendar(action) {
        if(action === undefined)
            action = "current";

        $.ajax({
            url: "/orarend",
            type: "POST",
            data: {'date': $('#orarend').attr('data-start-date'), 'action': action},
            success: function (data) {
                $("#schedule-date-start").text(data.start.replace(/-/gi, "."));
                $("#schedule-date-end").text(data.end.replace(/-/gi, "."));
                $("#orarend").attr('data-start-date',data.start);

                if(data.hasnext)
                    $(".fa-arrow-right").show();
                else
                    $(".fa-arrow-right").hide();

                if(data.hasprev)
                    $(".fa-arrow-left").show();
                else
                    $(".fa-arrow-left").hide();

                data.calendar.forEach(function(value,index){
                    var html = "";
                    value.forEach(function(myevent){
                        html += "<ul class=\"even\">" /* UL NYITÁS*/
                            + "<li>"+ myevent.training_name + "</li>" /* Edzés neve */
                            + "<li>"+ myevent.time_start.slice(0, -3) + "-" + myevent.time_end.slice(0, -3) +"</li>" /* Mettől meddig */
                            + "<li>"+ myevent.trainer_name +"</li>"; /* Edző neve */
                        if(myevent.ended){
                            console.log(myevent.ended,myevent.time_start.slice(0, -3));
                            html += "<li><a>Véget ért</a></li></ul>";
                        }
                        else if(myevent.has_capacity == "1")
                            html += "<li><a event-id=\""+ myevent.id +"\" class=\"btn-reservation\">Jelentkezés</a></li></ul>"; /* Jelentkezés gomb */
                        else
                            html += "<li><a>Megtelt</a></li></ul>"; /* Jelentkezés gomb */
                    });
                    $("#"+weekday[index]).html(html);
                });
            }
        });
    }