import { useRef, useState, useCallback } from 'react'
import { MorseAudioEngine } from '../lib/audio'
import { DEFAULT_WPM } from '../lib/morse'

type SignalType = 'dot' | 'dash' | null

export function useMorseAudio() {
  const engineRef = useRef<MorseAudioEngine | null>(null)
  const [isPlaying, setIsPlaying] = useState(false)
  const [currentSignal, setCurrentSignal] = useState<SignalType>(null)

  function getEngine() {
    if (!engineRef.current) {
      const engine = new MorseAudioEngine()
      engine.on('signal-start', ({ type }: { type: 'dot' | 'dash' }) => setCurrentSignal(type))
      engine.on('signal-end', () => setCurrentSignal(null))
      engine.on('play-end', () => { setIsPlaying(false); setCurrentSignal(null) })
      engineRef.current = engine
    }
    return engineRef.current
  }

  const play = useCallback((text: string) => {
    const engine = getEngine()
    engine.stop()
    setIsPlaying(true)
    setCurrentSignal(null)
    engine.play(text, DEFAULT_WPM)
  }, [])

  const stop = useCallback(() => {
    engineRef.current?.stop()
    setIsPlaying(false)
    setCurrentSignal(null)
  }, [])

  return { play, stop, isPlaying, currentSignal }
}