Function useInterval

src/ink/hooks/use-interval.ts:43–67

(
  callback: () => void,
  intervalMs: number | null,
)

 * one wake-up. Pass `null` for intervalMs to pause.
 */
export function useInterval(
  callback: () => void,
  intervalMs: number | null,
): void {
  const callbackRef = useRef(callback)
  callbackRef.current = callback

  const clock = useContext(ClockContext)

  useEffect(() => {
    if (!clock || intervalMs === null) return

    let lastUpdate = clock.now()

    const onChange = (): void => {
      const now = clock.now()
      if (now - lastUpdate >= intervalMs) {
        lastUpdate = now
        callbackRef.current()
      }
    }

    return clock.subscribe(onChange, false)
  }, [clock, intervalMs])
}