Google Calendar - add event duration

calendar.js

//cdnjs.cloudflare.com/ajax/libs/moment.js/2.13.0/moment.min.js
//code.jquery.com/jquery-2.2.3.min.js

var events, checkEvents;

var roundHalf = function(num) {
    return Math.round(num*2)/2;
}

var addDuration = function() {
    $(".cbrd").each(function(){
        var interval, text, time;
        text = $(this).find('.chip-caption')
            .clone()
            .children()
            .remove()
            .end()
            .text();
        interval = text.split('–');
        interval[0] = $.trim(interval[0]);
        if (interval.length === 2) {
            interval[1] = $.trim(interval[1]);
            var now = moment('2013-01-01T' + interval[0] + ':00.000');
            var end = moment('2013-01-01T' + interval[1] + ':00.000');
            var duration = moment.duration(end.diff(now));
            time = roundHalf(duration.asHours());
            
        } else {
            time = 0.5;
        }
        
        $(this).find('.chip-caption').text(text + '(' + time + ')');
        $(this).addClass('cbrd--count-added');
    });
};

checkEvents = setInterval(function(){
    var jq = $ || false;
    if (jq !== 'undefiend' && moment !== undefined) {
        events = $('.cbrd').length;
        filled = $('.cbrd--count-added').length;
        if (events !== 0 && filled === 0) {
            addDuration();
        }
    }
}, 1000);