import java.util.Scanner;

public class TicTacToe
{
    public static char[][] board = new char[3][3];
    public Scanner keyboard;


    public static void writeBoard()
    {
        System.out.println("-----------------");
        System.out.println("|R/C| 1 | 2 | 3 |");
        System.out.println("-----------------");

        for (int i = 0; i < 3; i++) //i is the row number
        {
            System.out.println("| " + (i + 1) + " | " + board[i][0] + " | " + board[i][1] + " | " + board[i][2] + " |");
            System.out.println("-----------------");
        }
    }

    /*Postcondition:
    Prints the TicTacToe board to screen with user moves in the correct rows and columns*/

    /*Precondition:
    The board has been written and a new game has been started or O has just placed their move*/

    public static void getMoveX()
    {
        System.out.println("X's turn.");
        System.out.println("Where would you like your X placed?");
        System.out.println("Please enter row number and column number separated by a space.");
        Scanner keyboard = new Scanner(System.in);
        String rowcol = keyboard.nextLine(); //user input assigned to rowcol
        int row = rowcol.charAt(0);
        int column = rowcol.charAt(2);
        System.out.println("You have entered row #" + (row - 48) + " and column #" + (column - 48)); /*prints the row and column that the user entered*/

        if (board[(row - 49)][(column - 49)] != '\0') /*if the spot entered by the user is taken...*/
        {
            System.out.println("That cell is already taken.");
            System.out.println("Please make another selection.");
            getMoveX();
        }

        else //if the spot is not taken...
        {
            System.out.println("Thank you for your selection.");
            board[row - 49][column - 49] = 'X'; //X assigned to user row and column
            winner(); //checks to see if X is winner
        }
    }

        /*Postcondition:
        Gets move from player X and places it in the correct spot on the board, prints board to screen*/

        /*Precondition:
        X has moved and has chosen a valid spot, there is no winner yet*/


    public static void getMoveO()
    {
                System.out.println("O's turn.");
                System.out.println("Where would you like your O placed?");
                System.out.println("Please enter row number and column number separated by a space.");
                Scanner keyboard = new Scanner(System.in);
                String rowcol1 = keyboard.nextLine(); //user input assigned to rowcol1
                int row1 = rowcol1.charAt(0);
                int column1 = rowcol1.charAt(2);
                System.out.println("You have entered row #" + (row1 - 48) + " and column #" + (column1 - 48)); /*prints the users row and column number*/
                row1--;
                column1--;

                if (board[row1 - 48][column1 - 48] != '\0') /*if the row and column are taken...*/
                {
                    System.out.println("That cell is already taken.");
                    System.out.println("Please make another selection.");
                    getMoveO(); //starts method over
                }
                else /*if row and column are not taken...*/
                {
                    System.out.println("Thank you for your selection.");
                    board[row1 - 48][column1 - 48] = 'O'; //O placed in designated row and column
                    winner(); //checks for winner
                }
    }

    /*Precondition:
    X or O have placed their move*/

    public static boolean winner()
    {
        boolean winner;

        /*checks rows to see if X is winner*/
        for (int i = 0; i < 3; i++)
        {
            if ((board[i][0] == 'X') && (board[i][0] == board[i][1]))
            {
                if (board[i][0] == board[i][2])
                {
                    winner = true;
                    System.out.println(board[i][0] + " IS THE WINNER!");
                    writeBoard();
                    System.exit(0);
                }
                else
                    winner = false;
            }

            else
                winner = false;
        }

        /*checks columns to see if X is winner*/
        for (int i = 0; i < 3; i++)
        {
            if ((board[0][i] == 'X') && (board[0][i] == board[1][i]))
            {
                if (board[0][i] == board[2][i])
                {
                    winner = true;
                    System.out.println(board[0][i] + " IS THE WINNER!");
                    writeBoard();
                    System.exit(0);
                }
                else
                    winner = false;
            }

            else
                winner = false;
        }

        /*checks diagonals to see if X is winner*/
        if ((board[0][0] == 'X') && (board[0][0] == board[1][1]))
        {
            if (board[0][0] == board[2][2])
            {
                winner = true;
                System.out.println(board[0][0] + " IS THE WINNER!");
                writeBoard();
                System.exit(0);
            }
            else
                winner = false;
        }

        if ((board[0][2] == 'X') && (board[0][2] == board[1][1]))
        {
            if (board[1][1] == board[2][0])
            {
                winner = true;
                System.out.println(board[0][2] + " IS THE WINNER!");
                writeBoard();
                System.exit(0);
            }
            else
                winner = false;
        }

        /*checks rows to see if O is winner*/
        for (int i = 0; i < 3; i++)
        {
            if ((board[i][0] == 'O') && (board[i][0] == board[i][1]))
            {
                if (board[i][0] == board[i][2])
                {
                    winner = true;
                    System.out.println(board[i][0] + " IS THE WINNER!");
                    writeBoard();
                    System.exit(0);
                }
                else
                    winner = false;
            }

            else
                winner = false;
        }

        /*checks columns to see if O is winner*/
        for (int i = 0; i < 3; i++)
        {
            if ((board[0][i] == 'O') && (board[0][i] == board[1][i]))
            {
                if (board[0][i] == board[2][i])
                {
                    winner = true;
                    System.out.println(board[0][i] + " IS THE WINNER!");
                    writeBoard();
                    System.exit(0);
                }
                else
                    winner = false;
            }

            else
                winner = false;
        }

        /*checks diagonals to see if O is winner*/
        if ((board[0][0] == 'O') && (board[0][0] == board[1][1]))
        {
            if (board[0][0] == board[2][2])
            {
                winner = true;
                System.out.println(board[0][0] + " IS THE WINNER!");
                writeBoard();
                System.exit(0);
            }
            else
                winner = false;
        }

        if ((board[0][2] == 'O') && (board[0][2] == board[1][1]))
        {
            if (board[1][1] == board[2][0])
            {
                winner = true;
                System.out.println(board[0][2] + " IS THE WINNER!");
                writeBoard();
                System.exit(0);
            }
            else
                winner = false;
        }
        else
            winner = false;

        return winner; //true or false
    }

    public static void newGame()
    {
        /*assigns null characters to all indexes in the array*/
        for (int i = 0; i < 3; i++)
        {
            board[i][0] = '\0';
            board[i][1] = '\0';
            board[i][2] = '\0';
        }

        System.out.println("New Game:  X goes first.");
    }

    /*Postcondition:
    Prints board to screen with blank board*/
}