/* Units: ms, s, m, h, d */
window.durationToString = function (duration, unit, minRate) {
  var str = ''
  unit = unit.toLowerCase()
  if (minRate === undefined) {
    minRate = 0.02
  }

  if (unit.startsWith('s')) {
    duration *= 1000
  } else if (unit == 'm' || unit.startsWith('min')) {
    duration *= 1000 * 60
  } else if (unit.startsWith('h')) {
    duration *= 1000 * 60 * 60
  } else if (unit.startsWith('d') || unit.startsWith('j')) {
    duration *= 1000 * 60 * 60 * 24
  }

  var saveDuration = duration
  var checkUnit = function (interval, name, twoDigitsMin) {
    var val = ~~(duration / interval)
    duration = duration - val * interval
    if (val > 0 && (val * interval) / saveDuration >= minRate) {
      if (val < 10 && twoDigitsMin === true) {
        str += '0'
      }
      str += val + name
    }
  }

  checkUnit(1000 * 60 * 60 * 24, 'j')
  checkUnit(1000 * 60 * 60, 'h', true)
  checkUnit(1000 * 60, 'm', true)
  checkUnit(1000, 's', true)
  checkUnit(1, 'ms')

  return str
}

/*  durationToString(61, 'm')          01h               */
/*  durationToString(62, 'm')          01h02m            */
/*  durationToString(61, 'm', 0)       01h01m            */
/*  durationToString(123.32, 'm')      02h03m            */
/*  durationToString(123.32, 'm', 0)   02h03m19s200ms    */
/*  durationToString(61, 'h')          2j13h             */
/*  durationToString(3, 'd')           3j                */
/*  durationToString(3.632, 'd')       3j15h             */
/*  durationToString(3.632, 'd', 0)    3j15h10m04s800ms  */