constexpr int OFF = HIGH;

// LEDs
constexpr int led1_pin = 13;
constexpr int led2_pin = 12;
constexpr int led3_pin = 11;
constexpr int led4_pin = 10;

// buttons
constexpr int button1_pin = A1;
constexpr int button2_pin = A2;
constexpr int button3_pin = A3;


  const int buttonPin = A1; // set the button pin
int value = 0; // initialize the value to zero
int lastButtonState = HIGH; // initialize the button state
unsigned long lastDebounceTime = 0; // the last time the button was toggled
unsigned long incrementTime = 0; // the last time the value was incremented
unsigned long holdTime = 0; // the time the button has been held down
const unsigned long debounceDelay = 50; // the debounce time; increase if the output flickers



bool checker = false;

const int LED_PINS[] = {led1_pin, led2_pin, led3_pin, led4_pin};
const int BUTTON_PINS[] = {button1_pin, button2_pin};

const int LONG_PRESS_DELAY = 1000;
const int LONG_PRESS_INTERVAL = 300;

unsigned long last_press_time[] = {0, 0};
unsigned long last_update_time = 0;

unsigned long current_time = 0;

int number = -1;

void setup() {
  for (int i = 0; i < 4; i++) {
    pinMode(LED_PINS[i], OUTPUT);
    digitalWrite(LED_PINS[i], OFF);
  }

  for (int i = 0; i < 2; i++) {
    pinMode(BUTTON_PINS[i], INPUT_PULLUP);
  }
  update_leds();
}

void update_leds() {
  for (int i = 0; i < 4; i++) {
    digitalWrite(LED_PINS[i], (number >> i) & 1);
  }
}

void loop() {
    current_time = millis();


    update_leds();
    last_update_time = current_time;


  // Check if button 2 was pressed
  if (digitalRead(BUTTON_PINS[1]) == LOW) {
    if (millis() - last_press_time[0] >= 10000 ) {
      number+=15;
      last_press_time[0] =  - 700;
    }
  } else {
    last_press_time[0] = 0;
  }


  number %= 16;




  int buttonState = digitalRead(buttonPin); // read the state of the button
  if (buttonState != lastButtonState) { // if the button state has changed
    lastDebounceTime = millis(); // record the time the button state changed
  }
  if ((millis() - lastDebounceTime) > debounceDelay) { // if the button state has been stable for the debounce time
    if (buttonState == LOW) { // if the button is pressed
      holdTime = millis(); // record the time the button was pressed
      incrementTime = millis(); // reset the increment time
    } else { // if the button is released
      if (holdTime > 0) { // if the button was held
        int increment = 0; // initialize the increment to zero
        if ((millis() - holdTime) >= 1000) { // if the button was held for at least 1000 ms
          increment = 1; // increment the value
          holdTime = millis(); // reset the hold time
        } else if ((millis() - incrementTime) >= 300) { // if the increment time has elapsed
          increment = 1; // increment the value
          incrementTime = millis(); // reset the increment time
        }
        if (increment) { // if the value should be incremented
          value++; // increment the value
          Serial.println(value); // print the value to the serial monitor
        }
      }
      holdTime = 0; // reset the hold time
    }
    lastButtonState = buttonState; // save the button state
  }
}

}