#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>

const byte ROWS = 4;
const byte COLS = 4;

char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

byte rowPins[ROWS] = {9, 8, 7, 6}; 
byte colPins[COLS] = {5, 4, 3, 2};

int Pin10 = 10;
int Pin11 = 11; 

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

LiquidCrystal_I2C lcd(0x27, 20, 4);

int randomNumber;
String userInput = "";

void setup()
{
  lcd.init();   
  lcd.backlight();
  pinMode(Pin10, OUTPUT);
  pinMode(Pin11, OUTPUT);
  randomSeed(analogRead(A0));
  randomNumber = random(1, 51);
  lcd.print("Guess number 1-50");
  delay(2000);
  lcd.clear();
  lcd.print("Enter number: ");
}

void loop() 
{
  char key = keypad.getKey();

  if (key)
  {
    if (key == '#') 
    {
      int guessedNumber = userInput.toInt(); 

      lcd.clear();
      if (guessedNumber == randomNumber) 
      {
        digitalWrite(Pin11, HIGH);
        lcd.print("Correct!");
        delay(3000);
        resetGame();
      } 
      else if (guessedNumber < randomNumber) 
      {
        lcd.print("Too low!");
        digitalWrite(Pin10, HIGH);
      } 
      else 
      {
        lcd.print("Too high!");
        digitalWrite(Pin10, HIGH);
      }
      delay(2000);
      digitalWrite(Pin10, LOW);
      userInput = "";
      lcd.clear();
      lcd.print("Enter number: ");
    } 
    else if (key == '*') 
    {
      userInput = "";
      lcd.clear();
      lcd.print("Enter number: ");
    } 
    else
    {
      if (userInput.length() < 2) 
      {
        userInput += key;
        lcd.setCursor(13, 0);
        lcd.print(userInput);
      }
    }
  }
}


void resetGame() 
{
  digitalWrite(Pin11, LOW);
  randomNumber = random(1, 21);
  userInput = "";
  lcd.clear();
  lcd.print("New game!");
  delay(2000);
  lcd.clear();
  lcd.print("Enter number: ");
}