#include <Servo.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Define the LCD display connections
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Define the servo motor
Servo myservo;
int servoPin = 10;

// Define the pin connections
int ledPin = 13;
int pirPin = 2;
int buttonPin = 9;

// Define the ultrasonic sensor pins
int trigPin = 6;
int echoPin = 7;

void setup() {
  // Initialize the servo motor
  myservo.attach(servoPin);

  // Initialize the LCD
  lcd.init();
  lcd.backlight();

  // Initialize the LED and motion sensor
  pinMode(ledPin, OUTPUT);
  pinMode(pirPin, INPUT);
  pinMode(buttonPin, INPUT_PULLUP);

  // Initialize the ultrasonic sensor
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  // Check if motion is detected
  if (digitalRead(pirPin) == HIGH) {
    // Turn on the LED
    digitalWrite(ledPin, HIGH);

    // Display message on LCD
    lcd.setCursor(0, 0);
    lcd.print("Feeding pet...");
    
    myservo.write(90); // Open the pet feeder   
    delay(5000); // Wait for 5 seconds
    myservo.write(0); // Close the pet feeder
   
    lcd.clear();  // Clear the LCD
    
    digitalWrite(ledPin, LOW); // Turn off the LED
  }

  if (digitalRead(buttonPin) == LOW) {
      myservo.write(90); // Unlock the pet feeder
      lcd.setCursor(0, 0);
      lcd.print("Feeding pet...");
    } else {
      myservo.write(0); // Lock the pet feeder
      lcd.clear();  // Clear the LCD
    }

  // Check the food level
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  int duration = pulseIn(echoPin, HIGH);
  int distance = (duration / 2) / 29.1;

  if (distance < 5) {
    lcd.setCursor(0, 1);
    lcd.print("Food level: Full");
  } else {
    lcd.setCursor(0, 1);
    lcd.print("Food level: Low");
  }

  delay(500); // Debounce delay
}