const int buttonPin = 26;  
const int ledPin = 27;     

bool ledBlinking = false;  // Flag to track LED blinking state
unsigned long lastPressTime = 0; // Timestamp of the last button press
unsigned long debounceDelay = 50; // Debounce delay in milliseconds

void setup() {
  pinMode(ledPin, OUTPUT);        // Set LED pin as output
  pinMode(buttonPin, INPUT_PULLUP); // Set button pin as input with internal pull-up resistor
}

void loop() {
  // the loop function runs over and over again forever

      static bool lastButtonState = HIGH; // Previous button state
      bool currentButtonState = digitalRead(buttonPin); // Current button state
    
      // Check for button press with debounce, was previously not pressed, and is now pressed
      if (lastButtonState == HIGH && currentButtonState == LOW && (millis() - lastPressTime) > debounceDelay) { // Ensure debounceDelay time has passed since the last press
        lastPressTime = millis();                      // Update lastPressTime to the current time (from millis())
        ledBlinking = !ledBlinking;                   // Toggle LED blinking state
      }
      lastButtonState = currentButtonState;              //Update lastButtonState to the current state for the next loop iteration
    
      if (ledBlinking) { //If the LED is in blinking mode
        // Blink LED twice with a 0.5s delay
        for (int i = 0; i < 2; i++) {                    // A loop to blink the LED twice
          digitalWrite(ledPin, HIGH);                   //Turn ON LED for 0.5 s
          delay(500);
          digitalWrite(ledPin, LOW);                   //Turn Off LED for 0.5 s
          delay(500);
        }
        ledBlinking = false;                          // Reset after blinking
      } else { //  If ledBlinking is false, the LED remains off
        digitalWrite(ledPin, LOW);                   // LED is off when not blinking
      }
    }