// TicTacToe Game
// Chris Wilcox
// wilcox
// 11/10/2012
// CS160

import java.util.Random;
import java.util.Scanner;

public class TicTacToe { 

    public enum eStatus {
        IN_PROGRESS,
        TIE_GAME,
        COMPUTER_WINS,
        PLAYER_WINS,
    }
    
    public char board[][] = new char[3][3];
    public Scanner keyboard;
    public Random random;
    
    // Constructor
    public TicTacToe() {
        
        // Create scanner
        keyboard = new Scanner(System.in);
        
        // Create random
        random = new Random();

        // Initialize board
        initBoard();
    }
    
    // Main program
    public static void main(String args[]) {
        
        // Instantiate class
        TicTacToe tictactoe = new TicTacToe();
        
        // Computer starts
        boolean nextTurn = false;
        
        while (tictactoe.status() == eStatus.IN_PROGRESS) {
    
            // Next move
            if (nextTurn)
                tictactoe.player();
            else
                tictactoe.computer();
            
            // Display board
            tictactoe.printBoard();

            nextTurn = !nextTurn;
        } 
        
        // Print status
        eStatus status = tictactoe.status();
        if (status == eStatus.TIE_GAME)
            System.out.println("Game is tied!");
        else if (status == eStatus.COMPUTER_WINS)
            System.out.println("Computer wins!");
        else if (status == eStatus.PLAYER_WINS)
            System.out.println("Player wins!");
    }
    
    // Initialize board
    private void initBoard() {
        for (int row = 0; row <= 2; ++row) {
            for (int col = 0; col <= 2; ++col) {
                board[row][col] = '-';
            }
        }
    }

    // Print board
    private void printBoard() {
        System.out.println("------------------------------");
        for (int row = 0; row <= 2; ++row) {
            for (int col = 0; col <= 2; ++col) {
                System.out.print("  " + board[row][col]);
            }
            System.out.println();
        }
        System.out.println();
    }
    
    // Game status
    private void markSquare(int row, int col, char c) {

        // Mark square
        board[row][col] = c;
    }

    // Computer moves
    private void computer() {

        while (true) {
        
            int row = (int) random.nextInt(3);
            int col = (int) random.nextInt(3);

            // Check occupied
            if (board[row][col] == '-') {
                markSquare(row, col, 'X');
                break;
            }
        }
    }

    // Player moves
    private void player() {

        while (true) {

            System.out.print("Row: ");
            int row = keyboard.nextInt();
            System.out.print("Column: ");
            int col = keyboard.nextInt();
        
            // Check range
            if ((row < 0) || (row > 2))
                System.out.println("Row out of range, try again!");
            else if ((col < 0) || (col > 2))
                System.out.println("Column out of range, try again!");

            // Check occupied
            else if (board[row][col] != '-')
                System.out.println("Occupied square, try again!");
            
            // Valid move
            else {
                markSquare(row, col, 'O');
                break;
            }
        }
    }

    // Game status
    private eStatus status() {

        // Check tie
        boolean tieGame = true;
        for (int row = 0; row <= 2; ++row)
            for (int col = 0; col <= 2; ++col)
                    if (board[row][col] == '-')
                        tieGame = false;
        // Tie game
        if (tieGame)
            return eStatus.TIE_GAME;
        
        // Player wins
        else if (runOfThree('O'))
            return eStatus.PLAYER_WINS;

        // Computer wins
        else if (runOfThree('X'))
            return eStatus.COMPUTER_WINS;

        return eStatus.IN_PROGRESS;
    }

    // Run of three?
    private boolean runOfThree(char c) {

        // Check rows
        for (int row = 0; row <= 2; ++row) {
            if ((board[row][0] == c) &&
                (board[row][1] == c) &&
                (board[row][2] == c))
                return true;
        }
        
        // Check columns
        for (int col = 0; col <= 2; ++col) {
            if ((board[0][col] == c) &&
                (board[1][col] == c) &&
                (board[2][col] == c))
                return true;
        }
        
        // Check diagonals
        if ((board[0][0] == c) && 
            (board[1][1] == c) &&
            (board[2][2] == c))
            return true;
        if ((board[2][0] == c) && 
            (board[1][1] == c) &&
            (board[0][2] == c))
            return true;

        return false;
    }
}