// Простой синтез звука через Web Audio API — без внешних аудиофайлов.
let ctx = null;

function ensureCtx() {
  if (!ctx) {
    const AudioCtx = window.AudioContext || window.webkitAudioContext;
    ctx = new AudioCtx();
  }
  if (ctx.state === 'suspended') {
    ctx.resume();
  }
  return ctx;
}

// Вызывать из обработчика реального пользовательского клика/нажатия —
// браузеры блокируют автозапуск звука без явного жеста.
export function unlockAudio() {
  ensureCtx();
}

function beep({ freq, duration = 0.08, type = 'square', gain = 0.1, freqEnd = null }) {
  const c = ensureCtx();
  const osc = c.createOscillator();
  const g = c.createGain();
  osc.type = type;
  osc.frequency.setValueAtTime(freq, c.currentTime);
  if (freqEnd !== null) {
    osc.frequency.linearRampToValueAtTime(freqEnd, c.currentTime + duration);
  }
  g.gain.setValueAtTime(gain, c.currentTime);
  g.gain.exponentialRampToValueAtTime(0.0001, c.currentTime + duration);
  osc.connect(g).connect(c.destination);
  osc.start();
  osc.stop(c.currentTime + duration);
}

function noiseBurst({ duration = 0.2, gain = 0.18 } = {}) {
  const c = ensureCtx();
  const size = Math.max(1, Math.floor(c.sampleRate * duration));
  const buffer = c.createBuffer(1, size, c.sampleRate);
  const data = buffer.getChannelData(0);
  for (let i = 0; i < size; i++) {
    data[i] = (Math.random() * 2 - 1) * (1 - i / size);
  }
  const source = c.createBufferSource();
  source.buffer = buffer;
  const g = c.createGain();
  g.gain.setValueAtTime(gain, c.currentTime);
  source.connect(g).connect(c.destination);
  source.start();
}

export function playShot() {
  beep({ freq: 660, freqEnd: 220, duration: 0.06, type: 'square', gain: 0.08 });
}

export function playWallHit() {
  noiseBurst({ duration: 0.08, gain: 0.1 });
}

export function playExplosion() {
  noiseBurst({ duration: 0.25, gain: 0.18 });
  beep({ freq: 120, freqEnd: 40, duration: 0.25, type: 'sawtooth', gain: 0.1 });
}

export function playWin() {
  [523, 659, 784, 1047].forEach((freq, i) =>
    setTimeout(() => beep({ freq, duration: 0.15, type: 'square', gain: 0.1 }), i * 110)
  );
}

export function playLose() {
  [392, 330, 262, 196].forEach((freq, i) =>
    setTimeout(() => beep({ freq, duration: 0.2, type: 'sawtooth', gain: 0.1 }), i * 130)
  );
}