#define back  A0
#define ok  A3
#define up  A1
#define down  A2
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

int layar, menu, absen;
void setup() {
  pinMode(back, INPUT_PULLUP);
  pinMode(ok, INPUT_PULLUP);
  pinMode(up, INPUT_PULLUP);
  pinMode(down, INPUT_PULLUP);
  lcd.init();
  lcd.backlight();
  lcd.setCursor(1,0);
  lcd.print("SELAMAT DATANG");
  delay(2000);
  lcd.clear();

}

void loop() {
  // put your main code here, to run repeatedly:
   bacatombol();
   if (layar == 0){ //MAIN MENU
    lcd.setCursor(0,0);
    lcd.print("MENU A");
    lcd.setCursor(0,1);
    lcd.print("MENU B");
    
    if(menu == 0){  //tanda panah
      lcd.setCursor(14,0);
      lcd.print("<<");
      lcd.setCursor(14,1);
      lcd.print("  ");
    }
    else if(menu == 1){
      lcd.setCursor(14,0);
      lcd.print("  ");
      lcd.setCursor(14,1);
      lcd.print("<<");
    }
  }
  else if(layar == 1){
    lcd.setCursor(0,0);
    lcd.print("MENU B");
    lcd.setCursor(0,1);
    lcd.print("MENU C");

    if(menu == 2){  //tanda panah
      lcd.setCursor(14,0);
      lcd.print("<<");
      lcd.setCursor(14,1);
      lcd.print("  ");
    }
    else if(menu == 3){
      lcd.setCursor(14,0);
      lcd.print("  ");
      lcd.setCursor(14,1);
      lcd.print("<<");
    }
  }
  else if(layar == 2){  //GRUP B
    lcd.setCursor(0,0);
    lcd.print("MENU C");
    lcd.setCursor(0,1);
    lcd.print("MENU D");
  }
    if(menu == 4){  //tanda panah
      lcd.setCursor(14,0);
      lcd.print("<<");
      lcd.setCursor(14,1);
      lcd.print("  ");
    }
    else if(menu == 5){
      lcd.setCursor(14,0);
      lcd.print("  ");
      lcd.setCursor(14,1);
      lcd.print("<<");
    }

}

void bacatombol(){
  if (digitalRead(back)==0){
    if(layar = 0) {
      layar = 0;
      lcd.clear();
    }
    else if (layar = 1){
      layar = 0;
      lcd.clear();
    }
    else if (layar = 2){
      layar = 1;
      lcd.clear();
    }

  }
  else if (layar == 0){
    if (digitalRead(ok)==0){
    lcd.clear();
      if(menu == 0) {
        layar = 3;
        lcd.setCursor(0,0);
        lcd.print("heheh haiii");
      }
      else if (menu == 1) {
        layar = 4;
        lcd.setCursor(0,0);
        lcd.print("kenalin yaaaa");
      }
    }
    if (digitalRead(up)==0){
      menu = 0;
    }
    else if (digitalRead(down)==0){
      if(menu == 0){
        layar = 0;
        menu = 1;
        delay(250);
      }
      else if(menu == 1){
        layar = 1;
        menu = 1;
        delay(250);
      }
    }
  
    
  }
  if (layar == 1){
    if (digitalRead(ok)==0){
      lcd.clear();
      if(menu==0) {
        layar = 4;
        lcd.setCursor(0,0);
        lcd.print("kenalin yaaaa");
      }
      else if (menu==1){
        layar = 5;
        lcd.setCursor(0,0);
        lcd.print("aku ULLY");
      }
    }
    if (digitalRead(up)==0){
      menu = 0;
    }
    else if (digitalRead(down)==0){
      if(menu == 0){
        layar = 1;
        menu = 1;
        delay(2000);
      }
      else if(menu == 1){
        layar = 2;
        menu = 1;
        delay(250);
      }
    }
  
  }
  else if (layar == 2){
    if(digitalRead(ok)==0){
      lcd.clear();
      if(menu==0){
        layar=5;
        lcd.setCursor(0,0);
        lcd.print("aku ULLY");
      }
      else if (menu==1){
        layar=6;
        lcd.setCursor(0,0);
        lcd.print("love youuuu");
      }
    }
  }
  
}