// 设置速度：轻快的120 BPM
ditty.bpm = 120;

// 定义几种不同的音色
const lead = synth.def((phase, env) => {
    // 主旋律音色：明亮的锯齿波
    return (phase % 1 - 0.5) * 2 * env.value;
});

const bass = synth.def((phase, env) => {
    // 贝斯音色：柔和的正弦波
    return Math.sin(phase * Math.PI * 2) * env.value;
});

const pad = synth.def((phase, env) => {
    // 和声音色：温暖的三角波
    return (Math.abs(phase % 1 - 0.5) * 4 - 1) * env.value;
});

const kick = synth.def((phase, env) => {
    // 底鼓音色
    const pitch = 100 + (1 - phase) * 50;
    const sine = Math.sin(phase * pitch);
    return sine * env.value;
});

const snare = synth.def((phase, env) => {
    // 军鼓音色：添加噪音
    const noise = Math.random() * 2 - 1;
    const tone = Math.sin(phase * 200);
    return (tone * 0.3 + noise * 0.7) * env.value;
});

const hihat = synth.def((phase, env) => {
    // 踩镲音色：纯噪音
    const noise = Math.random() * 2 - 1;
    return noise * env.value;
});

// 定义音符常量（C大调音阶）
const c4 = 261.63;
const d4 = 293.66;
const e4 = 329.63;
const f4 = 349.23;
const g4 = 392.00;
const a4 = 440.00;
const b4 = 493.88;
const c5 = 523.25;
const d5 = 587.33;
const e5 = 659.25;
const f5 = 698.46;
const g5 = 783.99;
const a5 = 880.00;
const b5 = 987.77;
const c6 = 1046.50;

// 低音区音符
const c2 = 65.41;
const g1 = 49.00;
const a1 = 55.00;
const f1 = 43.65;

// 主旋律循环
loop(() => {
    // 轻快的旋律：C大调上行
    lead.play(c5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(e5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(g5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(c6, { attack: 0.01, release: 0.3, duration: 0.5 });
    sleep(0.5);
    
    lead.play(b4, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(d5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(f5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(b5, { attack: 0.01, release: 0.3, duration: 0.5 });
    sleep(0.5);
    
    lead.play(a4, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(c5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(e5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(a5, { attack: 0.01, release: 0.3, duration: 0.5 });
    sleep(0.5);
    
    lead.play(g4, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(b4, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(d5, { attack: 0.01, release: 0.15, duration: 0.25 });
    sleep(0.25);
    lead.play(g5, { attack: 0.01, release: 0.3, duration: 0.5 });
    sleep(0.5);
    
}, { name: 'Melody' });

// 和声循环（分解和弦）
loop(() => {
    // C 和弦
    pad.play(c4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(e4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(g4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(c5, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    
    // G7 和弦
    pad.play(g3, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(b3, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(d4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(f4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    
    // Am 和弦
    pad.play(a3, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(c4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(e4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(a4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    
    // F 和弦
    pad.play(f3, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(a3, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(c4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    pad.play(f4, { attack: 0.05, release: 0.2, duration: 0.5 });
    sleep(0.5);
    
}, { name: 'Harmony' });

// 贝斯循环
loop(() => {
    bass.play(c2, { attack: 0.02, release: 0.3, duration: 0.5 });
    sleep(0.5);
    bass.play(g1, { attack: 0.02, release: 0.3, duration: 0.5 });
    sleep(0.5);
    bass.play(a1, { attack: 0.02, release: 0.3, duration: 0.5 });
    sleep(0.5);
    bass.play(f1, { attack: 0.02, release: 0.3, duration: 0.5 });
    sleep(0.5);
    bass.play(c2, { attack: 0.02, release: 0.3, duration: 0.5 });
    sleep(0.5);
    bass.play(g1, { attack: 0.02, release: 0.3, duration: 0.5 });
    sleep(0.5);
    bass.play(a1, { attack: 0.02, release: 0.5, duration: 1 });
    sleep(1);
    
}, { name: 'Bass' });

// 鼓点循环
let beatCount = 0;
loop(() => {
    // 底鼓：第1、3拍
    if (beatCount % 2 === 0) {
        kick.play(80, { attack: 0.001, release: 0.1, duration: 0.25 });
    }
    sleep(0.25);
    
    // 军鼓：第2、4拍
    if (beatCount % 2 === 1) {
        snare.play(200, { attack: 0.001, release: 0.1, duration: 0.25 });
    }
    sleep(0.25);
    
    // 踩镲：每拍都响
    hihat.play(0, { attack: 0.001, release: 0.05, duration: 0.125 });
    sleep(0.125);
    hihat.play(0, { attack: 0.001, release: 0.05, duration: 0.125 });
    sleep(0.125);
    
    beatCount = (beatCount + 1) % 4;
    
}, { name: 'Drums' });