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

#define LEFT_SERVO_PIN 11
#define RIGHT_SERVO_PIN 12
#define PIR_SENSOR_PIN 2

Servo leftServo;
Servo rightServo;
LiquidCrystal_I2C lcd(0x27, 16, 2); // Address for the LCD1602
const int numSlots = 2; // Number of parking slots
int freeSlots = numSlots;
int filledSlots = 0;

const int trigPins[numSlots] = {3, 5}; // Ultrasonic sensor trigger pins
const int echoPins[numSlots] = {4, 6}; // Ultrasonic sensor echo pins

long duration;
int distance;

void setup() {
  leftServo.attach(LEFT_SERVO_PIN);
  rightServo.attach(RIGHT_SERVO_PIN);
  pinMode(PIR_SENSOR_PIN, INPUT);
  Wire.begin(); // Initialize the I2C library
  
  lcd.init(); // Initialize the LCD
  lcd.backlight(); // Turn on backlight
  lcd.print("Smart Parking"); // Display Smart Parking System
  lcd.setCursor(0, 1); // Move cursor to the second line
  lcd.print("System");
  delay(2000); // Display for 2 seconds
  lcd.clear(); // Clear the display
}

void loop() {
  for (int i = 0; i < numSlots; i++) {
    distance = getDistance(trigPins[i], echoPins[i]);
    if (distance < 10) {
      if (filledSlots < numSlots) {
        filledSlots++;
        freeSlots--;
      }
    }
  }
  
  int motionDetected = digitalRead(PIR_SENSOR_PIN);
  if (motionDetected == HIGH) {
    lcd.clear();
    lcd.print("Human detected");
    lcd.setCursor(0, 1);
    lcd.print("Drive carefully");
    delay(2000); // Display message for 2 seconds
  } else {
    lcd.clear();
    lcd.print("Free: ");
    lcd.print(freeSlots);
    lcd.print("  Filled: ");
    lcd.print(filledSlots);
  }
}

int getDistance(int trigPin, int echoPin) {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;
  return distance;
}