// Pin Definitions
const int pirPin = 2;       // PIR sensor output
const int buzzerPin = 8;    // Buzzer
const int greenLed = 3;     // Idle LED
const int redLed = 4;       // Alert LED

void setup() {
  pinMode(pirPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(greenLed, OUTPUT);
  pinMode(redLed, OUTPUT);

  digitalWrite(buzzerPin, LOW);
  digitalWrite(greenLed, HIGH); // System ready
  digitalWrite(redLed, LOW);

  Serial.begin(9600);
}

void loop() {
  int motionDetected = digitalRead(pirPin);

  if (motionDetected == HIGH) {
    Serial.println("Motion Detected!");
    digitalWrite(buzzerPin, HIGH);
    digitalWrite(redLed, HIGH);
    digitalWrite(greenLed, LOW);
    delay(500); // Alarm duration
  } else {
    digitalWrite(buzzerPin, LOW);
    digitalWrite(redLed, LOW);
    digitalWrite(greenLed, HIGH);
  }
}