/*
 Controlling a servo position using a potentiometer (variable resistor)
 by Michal Rinott <http://people.interaction-ivrea.it/m.rinott>

 modified on 8 Nov 2013
 by Scott Fitzgerald
 http://www.arduino.cc/en/Tutorial/Knob
*/

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

Servo myservo;  // create servo object to control a servo

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



int Slot = 4;      //Enter Total number of parking Slots
int flag1 = 0;
int flag2 = 0;

void setup() {
  myservo.attach(9);  // attaches the servo on pin 9 to the servo object
  myservo.write(180);
  pinMode(A0, INPUT_PULLUP);
  pinMode(A1, INPUT_PULLUP);

  lcd.print(" PARKING SYSTEM ");
  delay (2000);
  lcd.clear();
}

void loop() {
 
  // Entry Red
  if(!digitalRead(A0) && flag1==0){
    if(Slot>0){
      flag1=1;
      if(flag2==0){
        myservo.write(90); 
        Slot = Slot-1;
        }
    }else {
      lcd.print(" Parking Full ");
      delay (3000);
      lcd.clear();
    }
  } 

  // Exit Blue
  if(!digitalRead(A1) && flag2 == 0){
    flag2 = 1;
    if (flag1 == 0){
      myservo.write(90);
      Slot = Slot+1;
    }
  } 

  if (flag1 == 1 && flag2 == 1){
    delay (1000);
    myservo.write(180);
    flag1=0, flag2=0;
    lcd.print(Slot);
    delay (1000);
    lcd.clear();
  }  

}