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

// Declare Servos
Servo servoIn;
Servo servoOut;

// IR Sensor Pins
const int sensorIn = 2;  // IR sensor for CAR IN
const int sensorOut = 3; // IR sensor for CAR OUT

// Counter Variables
int carCount = 0;
const int parkingLimit = 5;  // Maximum parking capacity

// Servo Positions
int openPosition = 90;  // Open position (90 degrees)
int closePosition = 0;  // Closed position (0 degrees)

// LCD Initialization
LiquidCrystal_I2C lcd(0x27, 16, 2);  // Change 0x27 to your LCD's I2C address

void setup() {
  // Attach Servos
  servoIn.attach(9);    // Servo for CAR IN
  servoOut.attach(10);  // Servo for CAR OUT

  // Set Servo Initial Positions
  servoIn.write(closePosition);
  servoOut.write(closePosition);

  // IR Sensor Pins
  pinMode(sensorIn, INPUT);
  pinMode(sensorOut, INPUT);

  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Parking System");
  delay(2000);  // Display welcome message
  lcd.clear();
  updateLCD();

  // Initialize Serial Monitor
  Serial.begin(9600);
}

void loop() {
  // Check CAR IN sensor
  if (digitalRead(sensorIn) == HIGH) {
    if (carCount < parkingLimit) {
      Serial.println("Car detected at entry!");
      // Open barricade
      servoIn.write(openPosition);
      delay(3000);  // Wait for car to pass
      servoIn.write(closePosition);
      delay(3000);

      // Increment car count
      carCount++;
      Serial.print("Cars in parking: ");
      Serial.println(carCount);

      // Update LCD
      updateLCD();
    } else {
      // Parking Full Message
      lcd.setCursor(0, 0);
      lcd.print("Parking Full!");
      lcd.setCursor(0, 1);
      lcd.print("Wait to Exit...");
      delay(2000);
      lcd.clear();
      updateLCD();
    }
  }

  // Check CAR OUT sensor
  if (digitalRead(sensorOut) == HIGH) {
    if (carCount > 0) {
      Serial.println("Car detected at exit!");
      // Open barricade
      servoOut.write(openPosition);
      delay(2000);  // Wait for car to pass
      servoOut.write(closePosition);
      delay(500);

      // Decrement car count
      carCount--;
      Serial.print("Cars in parking: ");
      Serial.println(carCount);

      // Update LCD
      updateLCD();
    }
  }
}

// Function to Update LCD
void updateLCD() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Cars: ");
  lcd.print(carCount);
  lcd.setCursor(0, 1);
  lcd.print("Limit: ");
  lcd.print(parkingLimit);
}