import { SOUNDS, SOUND_EVENT_HISTORY, SOUND_MASTER_VOLUME, SOUND_MAX_VOICES, SOUND_MUTED_KEY, type SoundId, type SoundPart } from '../../constants/sound.js';

export function createSound(options: { context?: () => AudioContext; storage?: Pick<Storage, 'getItem' | 'setItem'> } = {}) {
  let context: AudioContext | undefined, master: GainNode | undefined, muted = false;
  const events = new Set<string>(), voices = new Set<AudioScheduledSourceNode>();
  const storage = () => options.storage ?? globalThis.localStorage;
  try { muted = storage()?.getItem(SOUND_MUTED_KEY) === 'true'; } catch { /* Optional preference storage. */ }
  function stop() {
    for (const voice of voices) { try { voice.stop(); } catch { /* Already ended. */ } }
    voices.clear();
  }
  return {
    get muted() { return muted; },
    async unlock() {
      if (muted) return;
      try {
        if (!context) {
          context = options.context?.() ?? new AudioContext();
          master = context.createGain(); master.gain.value = SOUND_MASTER_VOLUME;
          const compressor = context.createDynamicsCompressor();
          master.connect(compressor); compressor.connect(context.destination);
        }
        if (context.state === 'suspended') await context.resume();
      } catch { /* Audio support/autoplay failures must not interrupt gameplay. */ }
    },
    setMuted(value: boolean) {
      muted = value; if (muted) stop();
      try { storage()?.setItem(SOUND_MUTED_KEY, String(value)); } catch { /* Keep the in-memory preference. */ }
    },
    stop,
    play(id: SoundId, key?: string, pan = 0) {
      if (key) {
        if (events.has(key)) return;
        events.add(key);
        if (events.size > SOUND_EVENT_HISTORY) events.delete(events.values().next().value!);
      }
      if (muted || !context || !master || context.state !== 'running' || (typeof document !== 'undefined' && document.hidden)) return;
      const ctx = context;
      for (const part of SOUNDS[id] as readonly SoundPart[]) {
        if (voices.size >= SOUND_MAX_VOICES) break;
        const at = ctx.currentTime + (part.delay ?? 0), end = at + part.duration;
        const envelope = ctx.createGain(), panner = ctx.createStereoPanner();
        panner.pan.value = Math.max(-1, Math.min(1, pan));
        envelope.gain.setValueAtTime(0, at);
        envelope.gain.linearRampToValueAtTime(part.volume, at + Math.min(.012, part.duration / 4));
        envelope.gain.exponentialRampToValueAtTime(.0001, end);
        envelope.gain.linearRampToValueAtTime(0, end + .01);
        envelope.connect(panner); panner.connect(master);
        let source: AudioScheduledSourceNode, filter: BiquadFilterNode | undefined;
        if (part.wave === 'noise') {
          const buffer = ctx.createBuffer(1, Math.ceil(ctx.sampleRate * (part.duration + .02)), ctx.sampleRate);
          const data = buffer.getChannelData(0);
          for (let i = 0; i < data.length; i++) data[i] = Math.random() * 2 - 1;
          const noise = ctx.createBufferSource(); noise.buffer = buffer; source = noise;
          filter = ctx.createBiquadFilter(); filter.type = 'lowpass';
          filter.frequency.setValueAtTime(part.from, at); filter.frequency.exponentialRampToValueAtTime(part.to, end);
          source.connect(filter); filter.connect(envelope);
        } else {
          const oscillator = ctx.createOscillator(); source = oscillator; oscillator.type = part.wave;
          oscillator.frequency.setValueAtTime(part.from, at); oscillator.frequency.exponentialRampToValueAtTime(part.to, end);
          source.connect(envelope);
        }
        voices.add(source);
        source.onended = () => { voices.delete(source); source.disconnect(); filter?.disconnect(); envelope.disconnect(); panner.disconnect(); };
        source.start(at); source.stop(end + .02);
      }
    },
  };
}
export const sound = createSound();

export function installSoundControls() {
  const button = document.getElementById('sound-toggle') as HTMLButtonElement;
  const refresh = () => { button.textContent = sound.muted ? '소리 켜기' : '소리 끄기'; button.setAttribute('aria-pressed', String(!sound.muted)); };
  refresh();
  button.onclick = () => { sound.setMuted(!sound.muted); refresh(); void sound.unlock(); };
  document.addEventListener('pointerdown', () => { void sound.unlock(); }, { passive: true });
  document.addEventListener('keydown', () => { void sound.unlock(); });
  document.addEventListener('click', event => {
    const target = event.target instanceof Element ? event.target.closest('button, summary') : null;
    if (!target || target.id === 'sound-toggle' || target.matches(':disabled')) return;
    void sound.unlock().then(() => sound.play('click'));
  }, true);
  document.addEventListener('visibilitychange', () => { if (document.hidden) sound.stop(); });
  window.addEventListener('pagehide', () => sound.stop());
}