// Pin assignments
const int trigPin = 16;
const int echoPin = 17;
const int ledPin  = 5;
const int ldrPin  = 34;

long duration;
int distance;
int lightValue;
int invertVal;

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600); // For debugging
}

void loop() {
  // --- Ultrasonic sensor measurement ---
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2; // Convert to cm

  // --- Photoresistor measurement ---
  lightValue = analogRead(ldrPin);
  invertVal = map(lightValue, 32, 4063, 4063, 32); // LDR in Wokwi give inverted value so I inverted it back to be same as slider of LDR

  // Debugging output
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.print(" cm | Light: ");
  Serial.println(invertVal);

  // --- Logic: LED ON only if motion detected AND low light ---
  // Motion detected if object < 20 cm
  // Low light if photoresistor value < 300 (adjust threshold as needed)
  if (distance > 0 && distance < 50 && invertVal < 800) {
    digitalWrite(ledPin, HIGH);
  } else {
    digitalWrite(ledPin, LOW);
  }

  delay(100);
}