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

LiquidCrystal lcd(12, 11, 10, 9, 8, 7);
Servo gate;

int entryIR = 2;
int exitIR = 3;
int ledPin = 6;
int buzzerPin = A0;

int totalSlots = 5;
int availableSlots = 5;

void setup() {
  lcd.begin(16, 2);
  gate.attach(A1);
  gate.write(0);

  pinMode(entryIR, INPUT);
  pinMode(exitIR, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);

  lcd.print("ProxiPark Ready");
  delay(1000);
}

void loop() {
  int entryVal = digitalRead(entryIR);
  int exitVal = digitalRead(exitIR);

  lcd.clear();

  // Vehicle Entry
  if (entryVal == LOW && availableSlots > 0) {
    gate.write(90);
    availableSlots = availableSlots - 1;
    delay(1000);
    gate.write(0);
  }

  // Vehicle Exit
  if (exitVal == LOW && availableSlots < totalSlots) {
    availableSlots = availableSlots + 1;
    delay(1000);
  }

  // Status Display
  if (availableSlots == 0) {
    lcd.print("PARKING FULL");

    // LED + Buzzer Blink
    digitalWrite(ledPin, HIGH);
    digitalWrite(buzzerPin, HIGH);
    delay(200);
    digitalWrite(ledPin, LOW);
    digitalWrite(buzzerPin, LOW);
    delay(200);

  } else {
    lcd.print("Slots Free:");
    lcd.setCursor(0, 1);
    lcd.print(availableSlots);
    digitalWrite(ledPin, LOW);
    digitalWrite(buzzerPin, LOW);
    delay(500);
  }
}