const int ledPin = 7;    // Pin for the LED
const int buttonPin = 8;  // Pin for the button
unsigned long previousMillis = 0;  // Stores the last time the LED was updated
const long interval = 3000;  // Interval at which to blink (milliseconds)
bool timerEnabled = false;  // Boolean to control timer on/off state
int buttonState = 0;        // Current state of the button

void setup() {
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);  // Button with internal pull-up resistor
  Serial.begin(9600);  // Initialize serial communication for debugging (optional)
}

void loop() {
  // Read the button state (LOW when pressed due to pull-up)
  buttonState = digitalRead(buttonPin);

  // Toggle the timer state if the button is pressed
  if (buttonState == LOW) {
    timerEnabled = !timerEnabled;  // Toggle the timer state
    delay(200);  // Simple debounce mechanism
    Serial.print("Timer state: ");
    Serial.println(timerEnabled ? "Enabled" : "Disabled");
  }

  // Only run the timer if it's enabled
  if (timerEnabled) {
    unsigned long currentMillis = millis();

    // Compare the current time to the previous time the LED was updated
    if (currentMillis - previousMillis >= interval) {
      // Save the last time the LED was toggled
      previousMillis = currentMillis;

      // Toggle the LED state
      digitalWrite(ledPin, !digitalRead(ledPin));
    }
  }
}