secondsToHourMinuteSecond(totalSeconds) {
  let hour = Math.floor(totalSeconds / 3600);
  let minute = Math.floor(totalSeconds % 3600 / 60);
  let seconds = Math.floor(totalSeconds % 3600 % 60);

  return `${('0' + hour).slice(-2)}:${('0' + minute).slice(-2)}:${('0' + seconds).slice(-2)}`
}

/*
returns total seconds to hh:mm:ss value.
e.g. 133 seconds = 00:02:13
*/