// Arduino code for:
// Task 1: Change LED state when button is pressed
// Task 2: Blinking LED active only when Task 1 LED is off

// Pin definitions
const int buttonPin = 7;    // Push button pin (changed to pin 7)
const int ledPin1 = 13;     // LED for Task 1
const int ledPin2 = 12;     // Blinking LED for Task 2

// Variables
int ledState1 = LOW;         // Current state of LED 1
int previousButtonState = LOW; // Previous state of the button
unsigned long previousMillis = 0; // Last time LED 2 was updated
const long blinkInterval = 500;  // Blink interval in milliseconds (0.5 seconds)

void setup() {
  // Initialize pins
  pinMode(buttonPin, INPUT);
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  
  // Initialize LEDs to their starting states
  digitalWrite(ledPin1, ledState1);
  digitalWrite(ledPin2, LOW);
  
  // For debugging
  Serial.begin(9600);
  Serial.println("Program started");
}

void loop() {
  // Read the current button state
  int currentButtonState = digitalRead(buttonPin);
  
  // Task 1: Check if button was pressed (LOW to HIGH transition)
  if (currentButtonState == HIGH && previousButtonState == LOW) {
    // Toggle LED state
    ledState1 = !ledState1;
    digitalWrite(ledPin1, ledState1);
    
    // Debug info
    Serial.print("Button pressed! LED1 is now: ");
    Serial.println(ledState1 ? "ON" : "OFF");
    
    // Small delay to avoid button bounce
    delay(50);
  }
  
  // Update previous button state
  previousButtonState = currentButtonState;
  
  // Task 2: Blink LED2 only when LED1 is off
  if (ledState1 == LOW) {
    // Current time
    unsigned long currentMillis = millis();
    
    // Check if it's time to blink
    if (currentMillis - previousMillis >= blinkInterval) {
      previousMillis = currentMillis;
      
      // Toggle LED2
      int ledState2 = digitalRead(ledPin2);
      digitalWrite(ledPin2, !ledState2);
    }
  } else {
    // If LED1 is on, make sure LED2 is off
    digitalWrite(ledPin2, LOW);
  }
}