#include <Servo.h>

#define TRIG_PIN 10
#define ECHO_PIN 11
#define SERVO_PIN 9
#define BUZZER_PIN 8
#define LED_PIN 7

Servo servoMotor;
int distance;
int previousDistance = 0;
bool doorOpen = false;
int threshold = 20; // Adjust this value according to your needs

void setup() {
  Serial.begin(9600);
  servoMotor.attach(SERVO_PIN);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(LED_PIN, OUTPUT);
}

void loop() {
  // Measure distance using ultrasonic sensor
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  distance = pulseIn(ECHO_PIN, HIGH) * 0.034 / 2; // Calculate distance in cm
  
  Serial.print("Distance: ");
  Serial.println(distance);

  // Check if the door needs to be opened or closed
  if (distance < threshold && !doorOpen) {
    openDoor();
    beep();
    flashLED();
  } else if (distance >= threshold && doorOpen) {
    closeDoor();
  }

  delay(100); // Adjust delay according to your needs
}

void openDoor() {
  // Open the door
  servoMotor.write(90); // Assuming 90 degrees is the open position
  doorOpen = true;
  Serial.println("Door opened");
}

void closeDoor() {
  // Close the door
  servoMotor.write(0); // Assuming 0 degrees is the closed position
  doorOpen = false;
  Serial.println("Door closed");
}

void beep() {
  // Activate the buzzer
  tone(BUZZER_PIN, 1000); // Adjust frequency as needed
  delay(1000); // Adjust duration as needed
  noTone(BUZZER_PIN);
}

void flashLED() {
  // Flash the LED
  digitalWrite(LED_PIN, HIGH);
  delay(1000); // Adjust duration as needed
  digitalWrite(LED_PIN, LOW);
}