const int pirPin = 2;           // PIR sensor pin
const int ldrPin = A0;          // LDR sensor pin
const int relayPin = 3;         // Relay pin for controlling the light bulb
int lightThreshold = 400;       // Adjust this value based on your room's lighting conditions
bool motionDetected = false;    // Flag to track motion detection

void setup() {
  pinMode(pirPin, INPUT);
  pinMode(relayPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int pirValue = digitalRead(pirPin);   // Read PIR sensor
  int ldrValue = analogRead(ldrPin);    // Read LDR sensor
  
  if (pirValue == HIGH) {
    Serial.println("Motion detected! Turning on light...");
    motionDetected = true;
  } else {
    Serial.println("No motion detected. Turning off light...");
    motionDetected = false;
  }

  if (motionDetected) {
    if (ldrValue < lightThreshold) {
      // If it's dark in the room, turn on the light bulb fully
      digitalWrite(relayPin, HIGH);
    } else {
      // If it's bright in the room, dim the light bulb
      int brightness = map(ldrValue, lightThreshold, 1023, 0, 255); // Map LDR value to PWM range (0-255)
      analogWrite(relayPin, brightness); // Set brightness of the light bulb
    }
  } else {
    // If no motion detected, turn off the light bulb
    digitalWrite(relayPin, LOW);
  }

  delay(1000); // Adjust the delay as needed
}