// https://www.instructables.com/Arduino-Dual-Function-Button-Long-PressShort-Press/
// if the button is reading HIGH (when pressed)

int LED1 = 8;
int LED2 = 13;
int button = 3;

boolean LED1State = false;
boolean LED2State = false;

long buttonTimer = 0;
long longPressTime = 1200;

boolean buttonActive = false;
boolean longPressActive = false;

unsigned long debounceTime = 100;

void checkButton() {
	static unsigned long longPressCount = 0;
	static unsigned long shortPressCount = 0;

  static unsigned long lastInterruptTime = 0;
  unsigned long interruptTime = millis();
  unsigned long timeDiff;

  timeDiff = interruptTime - lastInterruptTime;

	if (timeDiff > debounceTime) {
		// 按下按钮
		if (digitalRead(button) == HIGH) {
			if (buttonActive == false) {
				buttonActive = true;
				buttonTimer = millis();
			}

			if ((millis() - buttonTimer > longPressTime) && (longPressActive == false)) {
				++longPressCount;
				longPressActive = true;

				LED2State = !LED2State;
				digitalWrite(LED2, LED2State);

				Serial.print("A long press is detected, led2: ");
				Serial.print(LED2State);

				Serial.print("shortPressCount: ");
				Serial.print(shortPressCount);
				Serial.print(", longPressCount: ");
				Serial.println(longPressCount);
			}
		}
		// 松开按钮
		else {
			if (buttonActive == true) {
				// 长按松开触发
				if (longPressActive == true) {
					longPressActive = false;
				}
				else {
					++shortPressCount;
					LED1State = !LED1State;
					digitalWrite(LED1, LED1State);

					Serial.print("A short press is detected, led1: ");
					Serial.print(LED1State);
				}
				buttonActive = false;

				Serial.print("shortPressCount: ");
				Serial.print(shortPressCount);
				Serial.print(", longPressCount: ");
				Serial.println(longPressCount);
			}
		}

		lastInterruptTime = interruptTime;
	}
}

void setup() {
	Serial.begin(9600);
	pinMode(LED1, OUTPUT);
	pinMode(LED2, OUTPUT);
	digitalWrite(LED2, LED2State ? HIGH : LOW);
	pinMode(button, INPUT);
}

void loop() {
	checkButton();
}