/**
 * Reactive React hook for the unified event bus.
 * Returns recent events and refreshes on push.
 */
import { useEffect, useState } from 'react'
import { eventBus, type BusEvent } from '../lib/event-bus'

export function useEventBus(limit = 20, maxAgeMs = 5 * 60 * 1000): {
  events: BusEvent[]
  contextString: string
  clear: () => void
} {
  const [events, setEvents] = useState<BusEvent[]>([])

  useEffect(() => {
    eventBus.init()
    setEvents(eventBus.recent(limit, maxAgeMs))
    const unsub = eventBus.subscribe(() => {
      setEvents(eventBus.recent(limit, maxAgeMs))
    })
    // Light polling to refresh maxAge windows
    const iv = setInterval(() => {
      setEvents(eventBus.recent(limit, maxAgeMs))
    }, 15_000)
    return () => { unsub(); clearInterval(iv) }
  }, [limit, maxAgeMs])

  return {
    events,
    contextString: eventBus.contextString(limit, maxAgeMs),
    clear: () => eventBus.clear(),
  }
}