Find the difference of times

                     var start =lineDay;
                    log.debug("start function",start);
                    var end = currentTime;
                    log.debug("end function",end);

                    var timeDiff = diff(start,end);
                    log.debug("timeDiff",timeDiff);

                    function diff(start, end) {
                        start = start.split(":");
                        end = end.split(":");
                        var startDate = new Date(0, 0, 0, start[0], start[1], 0);
                         var endDate = new Date(0, 0, 0, end[0], end[1], 0);
                        var diff = endDate.getTime() - startDate.getTime();
                        var hours = Math.floor(diff / 1000 / 60 / 60);
                        diff -= hours * (1000 * 60 * 60);
                        var minutes = Math.floor(diff / 1000 / 60);
                        diff -= minutes * (1000 * 60);
                        var seconds = Math.floor(diff / 1000);

                        // If using time pickers with 24 hours format, add the below line get exact hours
                        if (hours < 0)
                            hours = hours + 24;

                        return (hours <= 9 ? "0" : "") + hours + ":" + (minutes <= 9 ? "0" : "") + minutes +":"+ (seconds<= 9 ? "0" : "") + seconds;
                    }