import { useEffect, useState } from 'react'

export function useCountdown(deadline: number) {
  const [now, setNow] = useState(Date.now())
  useEffect(() => {
    setNow(Date.now())
    if (deadline <= Date.now()) return
    const timer = window.setInterval(() => setNow(Date.now()), 1000)
    return () => clearInterval(timer)
  }, [deadline])
  return Math.max(0, Math.ceil((deadline - now) / 1000))
}