#include <Servo.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);


Servo myservo;


#define entry 2
#define exit 4


#define slot1 5
#define slot2 6
#define slot3 7




int S1 = 0, S2 = 0, S3 = 0;
int flag1 = 0, flag2 = 0;



void setup() {
  Serial.begin(9600);

  pinMode(slot1, INPUT);
  pinMode(slot2, INPUT);
  pinMode(slot3, INPUT);
 

  pinMode(entry, INPUT);
  pinMode(exit, INPUT);

  myservo.attach(3);
  myservo.write(90);

  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 1);
  lcd.print(" Hi Welcome ");
 
  delay(5000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("   Project Title  ");
  lcd.setCursor(0, 1);
  lcd.print("    Car  Parking  ");
  lcd.setCursor(0, 2);
  lcd.print("       System     ");
  delay(5000);
  lcd.clear();

  Read_Sensor();

  
}


void loop() {

  Read_Sensor();
  int slot = 3;
  int total = S1 + S2 + S3 ;
  slot = slot - total;
  lcd.setCursor(0, 0);
  lcd.print(" Available Slot: ");
  lcd.print(slot);
  lcd.print("    ");

  lcd.setCursor(0, 1);
  if (S1 == 1) {
    lcd.print("S1:Full ");
  


  } else {
    lcd.print("S1:Empty");

  }

  lcd.setCursor(11, 1);
  if (S2 == 1) {
    lcd.print("S2:Full ");
  

  } else {
    lcd.print("S2:Empty");

  }

  lcd.setCursor(0, 2);
  if (S3 == 1) {
    lcd.print("S3:Full ");
  


  } else {
    lcd.print("S3:Empty");

  }

  if (digitalRead(entry) == 0 && flag1 == 0) {
    if (slot > 0) {
      flag1 = 1;
      if (flag2 == 0) {
        myservo.write(0);
        slot = slot - 1;
      }
    } else {
      lcd.setCursor(0, 0);
      lcd.print(" Parking Full ");
      delay(1500);
    }
  }

  if (digitalRead(exit) == 0 && flag2 == 0) {
    flag2 = 1;
    if (flag1 == 0) {
      myservo.write(0);
      slot = slot + 1;
    }
  }

  if (flag1 == 1 && flag2 == 1) {
    delay(1000);
    myservo.write(90);
    flag1 = 0, flag2 = 0;
  }

  delay(1);
}


void Read_Sensor() {
  S1 = 0, S2 = 0, S3 = 0;


  if (digitalRead(slot1) == 0) {
    S1 = 1;
  }
  if (digitalRead(slot2) == 0) {
    S2 = 1;
  }
  if (digitalRead(slot3) == 0) {
    S3 = 1;
  }
}