// DOM
const beat = document.querySelector('#beat');

// エンベロープ（キック）
let optsMembrane = {
  pitchDecay: 0.001,
  envelope: {
    attack: 0.001 ,
    decay: 0.75 ,
    sustain: 0.01 ,
    release: 0.01 
  },
  volume: 25
}

// エンベロープ（スネア）
let optsNoiseSnare = {
  envelope: {
    attack: 0.001 ,
    decay: 0.5 ,
    sustain: 0.01
  }
}

// エンベロープ（ハイハット）
let optsNoiseHihat = {
  type: "brown",
  envelope: {
    attack: 0.001 ,
    decay: 0.03 ,
    sustain: 0
  }
}

// シンセ生成
const membrane = new Tone.MembraneSynth(optsMembrane).toMaster();
const noise1 = new Tone.NoiseSynth(optsNoiseSnare).toMaster();
const noise2 = new Tone.NoiseSynth(optsNoiseHihat).toMaster();

// シンセ実行
const kick = () => {
  membrane.triggerAttackRelease('C0','2n'); 
};

const snare = () => {
  noise1.triggerAttackRelease('8n');
};

const hihat = () => {
  noise2.triggerAttackRelease('32n');
};

let beatNumber = 8;
let beatLength = 4 / beatNumber;

//リズム設定
let kickRhythm = [
  ['0:' + beatLength * 0 + ':0'],
  ['0:' + beatLength * 4 + ':0'],
];

let snareRhythm = [
  ['0:' + beatLength * 2 + ':0'],
  ['0:' + beatLength * 6 + ':0'],
];

let hihatRhythm = [];
for(i = 0; i < beatNumber ; i++) {
  hihatRhythm.push('0:' + beatLength * i + ':0');
}

// シンセにリズムを設定
let kickPart = new Tone.Part(kick, kickRhythm).start();
let snarePart = new Tone.Part(snare, snareRhythm).start()
let hihatPart = new Tone.Part(hihat, hihatRhythm).start();

// ループ設定
kickPart.loop = true;
snarePart.loop = true;
hihatPart.loop = true;

// BPM設定
Tone.Transport.bpm.value = 100;

// クリックイベント
beat.addEventListener('click', () => {
  Tone.Transport.toggle();
}, false);