public class TicTacToe {

public static char[][] board = new char[3][3];
static Scanner scan = new Scanner(System.in);
public static String keepPlaying;
public static char yesOrNo;
public static boolean playing;
public static int row, col;
public static User human1 = new User();
public static User human2 = new User();

public static void main(String[] args) {

    human1.getUser1Name();
    human2.getUser2Name();

    System.out.println("nPlayer 1: " + human1.human1Name() + ": X's");
    System.out.println("Player 2: " + human2.human2Name() + ": O'sn");

    initializeBoard();
    displayBoard();

    playing = true;


    while (playing == true)
    {

        System.out.println("n" + human1.human1Name() + " it's your turn.");
        human1.getChoice();
        human1.convert();


        if (human1.returnRow() == 0 && human1.returnCol() == 0/* && board[0][0] == ' '*/)
        {
            board[0][0] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 0 && human1.returnCol() == 1 && board[1][0] == ' ')
        {
            board[1][0] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 0 && human1.returnCol() == 2 && board[2][0] == ' ')
        {
            board[2][0] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 1 && human1.returnCol() == 0 && board[0][1] == ' ')
        {
            board[0][1] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 1 && human1.returnCol() == 1 && board[1][1] == ' ')
        {
            board[1][1] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 1 && human1.returnCol() == 2 && board[2][1] == ' ')
        {
            board[2][1] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 2 && human1.returnCol() == 0 && board[0][2] == ' ')
        {
            board[0][2] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 2 && human1.returnCol() == 1 && board[1][2] == ' ')
        {
            board[1][2] = 'X';
            displayBoard();
        }
        else if (human1.returnRow() == 2 && human1.returnCol() == 2 && board[2][2] == ' ')
        {
            board[2][2] = 'X';
            displayBoard();
        }

        if (checkForWinner() == true)
        {
            System.out.println("n" + human1.human1Name() + " has won the game!!!");
            playAgain();
            if (playing == false)
            {
                break;
            }

        }

        if (board[0][0] != ' ' && board[0][1] != ' ' && board[0][2] != ' ' && board[1][0] != ' ' && board[1][1] != ' '
                && board[1][2] != ' ' && board[2][0] != ' ' && board[2][1] != ' ' && board[2][2] != ' ')
        {
            System.out.println("It's a draw!!!");
            playAgain();
            if (playing == false)
            {
                break;
            }
        }



        System.out.println("n" + human2.human2Name() + " it's your turn.");
        human2.getChoice();
        human2.convert();

        if (human2.returnRow() == 0 && human2.returnCol() == 0 /*&& board[0][0] == ' '*/)
        {
            board[0][0] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 0 && human2.returnCol() == 1 && board[1][0] == ' ')
        {
            board[1][0] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 0 && human2.returnCol() == 2 && board[2][0] == ' ')
        {
            board[2][0] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 1 && human2.returnCol() == 0 && board[0][1] == ' ')
        {
            board[0][1] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 1 && human2.returnCol() == 1 && board[1][1] == ' ')
        {
            board[1][1] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 1 && human2.returnCol() == 2 && board[2][1] == ' ')
        {
            board[2][1] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 2 && human2.returnCol() == 0 && board[0][2] == ' ')
        {
            board[0][2] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 2 && human2.returnCol() == 1 && board[1][2] == ' ')
        {
            board[1][2] = 'O';
            displayBoard();
        }
        else if (human2.returnRow() == 2 && human2.returnCol() == 2 && board[2][2] == ' ')
        {
            board[2][2] = 'O';
            displayBoard();
        }


        if (checkForWinner() == true)
        {
            System.out.println("n" + human2.human2Name() + " has won the game!!!");
            playAgain();
        }

        if (board[0][0] != ' ' && board[0][1] != ' ' && board[0][2] != ' ' && board[1][0] != ' ' && board[1][1] != ' '
                && board[1][2] != ' ' && board[2][0] != ' ' && board[2][1] != ' ' && board[2][2] != ' ')
        {
            System.out.println("It's a draw!!!");
            playAgain();
        }


    }


}

public TicTacToe() {

    board = new char[3][3];

}

public static void initializeBoard() {

    for (int row = 0; row < 3; row++)
        {
            for (int col = 0; col < 3; col++)
            {
                board[row][col] = ' ';
            }
        }
    }

public static void displayBoard() {

    System.out.println("    A   B   C");
    System.out.println("  -------------");

    for (int row = 0; row < 3; row++)
    {
        System.out.print((row + 1) + " | ");
        for (int col = 0; col < 3; col++)
        {
            System.out.print(board[row][col] + " | ");
        }
        System.out.println();
        System.out.println("  -------------");
    }
}

public static boolean checkForWinner() {

    if (board[0][0] == board[0][1] && board[0][1] == board[0][2] && board[0][1] != ' ')
    {
        return true;
    }
    if (board[1][0] == board[1][1] && board[1][1] == board[1][2] && board[1][1] != ' ')
    {
        return true;
    }
    if (board[2][0] == board[2][1] && board[2][1] == board[2][2] && board[2][1] != ' ')
    {
        return true;
    }
    if (board[0][0] == board[1][0] && board[1][0] == board[2][0] && board[1][0] != ' ')
    {
        return true;
    }
    if (board[0][1] == board[1][1] && board[1][1] == board[2][1] && board[1][1] != ' ')
    {
        return true;
    }
    if (board[0][2] == board[1][2] && board[1][2] == board[2][2] && board[1][2] != ' ')
    {
        return true;
    }
    if (board[0][0] == board[1][1] && board [1][1] == board[2][2] && board[1][1] != ' ')
    {
        return true;
    }
    if (board[0][2] == board [1][1] && board[1][1] == board[2][0] && board[1][1] != ' ')
    {
        return true;
    }

    return false;
}

public static boolean playAgain() {

    System.out.println("nWould you like to play again?");

        keepPlaying = scan.nextLine();

        yesOrNo = keepPlaying.toUpperCase().charAt(0);

    if (yesOrNo == 'N')
    {
        System.out.println("nThanks for playing!");
        playing = false;
        initializeBoard();
        return playing;
    }
        else if (yesOrNo == 'Y')
        {
            initializeBoard();
            displayBoard();
            return true;
        }
    return playing;
}

public static boolean notValid() {

    if (human1.returnRow() > 2 || human1.returnRow() < 0 || human1.returnCol() > 2 || human1.returnCol() < 0 || human2.returnRow() > 2
            || human2.returnRow() < 0 || human2.returnCol() > 2 || human2.returnCol() < 0 || !isEmpty())
    {
        System.out.println("Invalid");
        return true;
    }
    else
    {
        return false;
    }
}

public static boolean isEmpty() {

    if (board[0][0] == ' ' && board[0][1] == ' ' && board[0][2] == ' ' && board[1][0] == ' ' && board[1][1] == ' '
                && board[1][2] == ' ' && board[2][0] == ' ' && board[2][1] == ' ' && board[2][2] == ' ')
    {
        return true;
    }
    else
    {
        System.out.println("That position is taken.n");
        return false;
    }
}

else if (human2.returnRow() == 1 && human2.returnCol() == 1 && board[1][1]==' ')
    {
        board[1][1] = 'O';
        displayBoard();
    }

boolean turnOver = false;
while(!turnOver){
    if(board[human2.returnRow()][human2.returnCol()] != ' '){
    System.out.println("That space is taken")
    }else{
    if(human2.returnRow() == 1 && human2.returnCol() == 1){
      board[1][1] = 'O';
      displayBoard();
     }

   //other cases
   turnOver = true;
   }