#include <Servo.h>
#include <LiquidCrystal.h>

// Pin definitions
const int trigPin = 9;
const int echoPin = 10;
const int servoPin = 11;

// LCD setup
LiquidCrystal lcd(7, 6, 5, 4, 3, 2);

// Servo setup
Servo myServo;

// Variables to store distance
long duration;
int distance;
const int threshold = 50; // Threshold in centimeters (20 inches)

void setup() {
  // Start serial communication
  Serial.begin(9600);

  // Set up the ultrasonic sensor pins
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);

  // Initialize the servo
  myServo.attach(11);

  // Initialize the LCD
  lcd.begin(16, 2);
}

void loop() {
  // Clear previous readings on the LCD
  lcd.clear();
  
  // Trigger the ultrasonic sensor
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  // Measure the time taken for the echo to return
  duration = pulseIn(echoPin, HIGH);

  // Calculate the distance (in cm)
  distance = duration * 0.0344 / 2;

  // Check if the distance is within the threshold (20 inches / 50 cm)
  if (distance < threshold) {
    // Display the welcome message
    lcd.setCursor(0, 0);
    lcd.print("Hi, Welcome To");
    lcd.setCursor(0, 1);
    lcd.print("the Weisser Residence");
    
    // Move the servo to a predefined position (e.g., 90 degrees)
    myServo.write(90);
  } else {
    // Display the distance on the LCD
    lcd.setCursor(0, 0);
    lcd.print("Distance: ");
    lcd.setCursor(0, 1);
    lcd.print(distance);
    lcd.print(" cm");
    
    // Control the servo based on distance
    if (distance < 10) {
     myServo.write(90);
     delay(500);
     myServo.write(-90);
     
     
     }
  }

  // Delay for a short period before the next reading
  delay(500);
}