#define LedGreen 2
#define LedRed 3
#define GreenBtn 6
#define RedBtn 5

#include <LiquidCrystal.h>

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

String waitingMessage = "WAITING...      ";
String grantedMessage = "ACCESS GRANTED !";
String deniedMessage = "ACCESS DENIED !";

void setup() {
  pinMode(LedGreen, OUTPUT);
  pinMode(LedRed, OUTPUT);
  pinMode(GreenBtn, INPUT_PULLUP);
  pinMode(RedBtn, INPUT_PULLUP);

  lcd.begin(16, 2);
  lcd.print("WAITING...");
  WaitBtnClick();
}

void WaitBtnClick(){
  while(true){
    if (digitalRead(GreenBtn) == LOW) {
      Blink(1);
    }
    if (digitalRead(RedBtn) == LOW) {
      Blink(0);
    }
  }
}

void loop() {
}

void Blink(byte type){
  
  if(type == 0)
  {
      digitalWrite(LedRed, HIGH);
      lcd.setCursor(0,0);
      lcd.print(deniedMessage);
      delay(3000);
      digitalWrite(LedRed, LOW);
      lcd.setCursor(0,0);
      lcd.print(waitingMessage);
  }
  else
  {
      digitalWrite(LedGreen, HIGH);
      lcd.setCursor(0,0);
      lcd.print(grantedMessage);
      delay(3000);
      digitalWrite(LedGreen, LOW);
      lcd.setCursor(0,0);
      lcd.print(waitingMessage);
  }
}