#include <Bounce2.h>

const uint8_t PIN_K1 = 2;   // 轻击
const uint8_t PIN_K2 = 3;   // 重击
const uint8_t PIN_K3 = 4;   // 识破/取消

Bounce btn1 = Bounce(), btn2 = Bounce(), btn3 = Bounce();

enum State { READY, L1, L2, H3, H4, H5 };
State state = READY;

uint32_t comboTimer = 0;
const uint32_t COMBO_TIMEOUT = 700;   // 连段时间窗口，可调

void setup() {
  Serial.begin(115200);
  pinMode(PIN_K1, INPUT_PULLUP);
  pinMode(PIN_K2, INPUT_PULLUP);
  pinMode(PIN_K3, INPUT_PULLUP);
  btn1.attach(PIN_K1); btn2.attach(PIN_K2); btn3.attach(PIN_K3);
  btn1.interval(5); btn2.interval(5); btn3.interval(5);
}

void sendCombo(uint8_t id) {
  Serial.print("Combo "); Serial.println(id);   // 可通过串口发到 PC/灯板/舵机
}

void loop() {
  btn1.update(); btn2.update(); btn3.update();

  if (btn3.fell()) {            // 随时取消
    state = READY;
    Serial.println("Cancel");
    return;
  }

  switch (state) {
    case READY:
      if (btn1.fell()) {
        state = L1;
        comboTimer = millis();
        sendCombo(1);
      }
      break;

    case L1:
      if (millis() - comboTimer > COMBO_TIMEOUT) { state = READY; break; }
      if (btn1.fell())         { state = L2; comboTimer = millis(); sendCombo(2); }
      break;

    case L2:
      if (millis() - comboTimer > COMBO_TIMEOUT) { state = READY; break; }
      if (btn2.fell())         { state = H3; comboTimer = millis(); sendCombo(3); }
      break;

    case H3:
      if (millis() - comboTimer > COMBO_TIMEOUT) { state = READY; break; }
      if (btn2.fell())         { state = H4; comboTimer = millis(); sendCombo(4); }
      break;

    case H4:
      if (millis() - comboTimer > COMBO_TIMEOUT) { state = READY; break; }
      if (btn2.fell())         { state = H5; sendCombo(5); }  // 终结技
      break;

    case H5:                    // 打完 5 段自动复位
      state = READY;
      break;
  }
}