function pad(n: number) {
  return String(n).padStart(2, '0')
}

export function fmt(secs: number) {
  if (!secs || Number.isNaN(secs)) return '0:00'
  const s = Math.floor(secs)
  const m = Math.floor(s / 60)
  const h = Math.floor(m / 60)
  if (h > 0) {
    return `${h}:${pad(m % 60)}:${pad(s % 60)}`
  }
  return `${m}:${pad(s % 60)}`
}