import java.util.Scanner;

/**
 * TicTacToe game class
 * 
 * @author Devin Gray
 * @date 4/1/2016
 **/
public class TicTacToe
{
    private char[][] board;
    private int size;
    private char whosTurn;
    private static final char X = 'X';
    private static final char O = 'O';
    private static final char EMPTY = ' ';
    private String result = "";
    
    public TicTacToe(int size)
    {
        this.size = size;
        board = new char[size][size];
        initialize();
        whosTurn = X;
        //for fun, lets put an initial X in the middle
        //board[size/2][size/2] = X;
    }
    
    private void initialize()
    {
        for(int row=0; row < board.length; row++)
        {
            for(int col=0; col < board[row].length; col++)
            {
                board[row][col] = EMPTY;
            }
        }
    }
    
    public String toString()
    {
        String str = "";
        
        for(int row=0; row < board.length; row++)
        {
            //print out the values in each column
            for(int col=0; col < board[row].length; col++)
            {
                str += board[row][col];
                if(col != board[row].length - 1)
                    str += "|";
            }
            str += "\n";
            
            //draw separator
            if(row != board.length - 1)
            {

                for(int col=0; col < board[row].length; col++)
                {
                    str += "—";
                    if(col != board[row].length - 1)
                         str += "+";
                }
                str += "\n";
            }
        }
        return str;
    }
    
    public boolean gameOver()
    {
        if(horizontalLineExist())
        {
            return true;
        }
        if(verticalLineExists())
        {
            return true;
        }
        if(diagonalLineExists())
        {
            return true;
        }
        if(isFull()) {
            result = "Its a Cat Game!";
            return true;
        }
        return false;
    }
    
    public boolean isFull()
    {
        boolean isCat = true;
        for(int row=0; row < board.length; row++)
        {
            for(int col=0; col < board[row].length; col++)
            {
                if(board[row][col] == EMPTY)
                {
                    isCat = false;
                }
            }
        }
        return isCat;
    }
    
    public boolean horizontalLineExist()
    {
        int numInRow = 0;
        char testing = EMPTY;
        for(int row=0; row < board.length; row++)
        {
            numInRow = 0;
            for(int col=0; col < board[row].length; col++)
            {
                //inspect it
                if(board[row][col] != EMPTY && (col == 0 || testing == board[row][col]))
                {
                    if(col == 0)
                        testing = board[row][col];
                    numInRow++;
                }
                else
                {
                    break;
                }
            }
            if(numInRow == size)
            {
                result = "WINNER! " + testing + " has " + size + " in a row";
                return true;
            }
        }
        return false;
    }
    
    public boolean verticalLineExists()
    {
        int numInCol = 0;
        char testing = EMPTY;
        for(int col=0; col < size; col++)
        {
            numInCol = 0;
            for(int row=0; row < size; row++)
            {
                //inspect it
                if(board[row][col] != EMPTY && (row == 0 || testing == board[row][col]))
                {
                    if(row == 0)
                        testing = board[row][col];
                    numInCol++;
                }
                else
                {
                    break;
                }
            }
            if(numInCol == size)
            {
                result = "WINNER! " + testing + " has " + size + " in a column";
                return true;
            }
        }
        return false;
    }
    
    public boolean diagonalLineExists()
    {
        int numInDiagonal = 0;
        char testing = EMPTY;
        
        //only 2 cases 
        // - top left to bottom right
        // - bottom left to top right
        for(int i=0; i < size; i++)
        {
            int row = i;
            int col = i;
            if(board[row][col] != EMPTY && (i == 0 || testing == board[row][col]))
            {
                if(i == 0)
                    testing = board[row][col];
                numInDiagonal++;
            }
            else
            {
                break;
            }
        }
        if(numInDiagonal == size)
        {
            result = "WINNER! " + testing + " has " + size + " in a diagonal";
            return true;
        }
        
        numInDiagonal = 0;
        for(int i=0; i < size; i++)
        {
            int row = (size-1) - i;
            int col = i;
            if(board[row][col] != EMPTY && (i == 0 || testing == board[row][col]))
            {
                if(i == 0)
                    testing = board[row][col];
                numInDiagonal++;
            }
            else
            {
                break;
            }
        }
        if(numInDiagonal == size)
        {
            result = "WINNER! " + testing + " has " + size + " in a diagonal";
            return true;
        }
        return false;
    }
    
    public void makeMove()
    {
        //whos turn?
        int row = -1;
        int col = -1;
        
        //ask for move
        boolean validMove = false;
        while(!validMove)
        {
            Scanner in = new Scanner(System.in);
            System.out.println("Ok " + whosTurn + " tell me the row: ");
            row = in.nextInt();
            System.out.println("Ok " + whosTurn + " tell me the col: ");
            col = in.nextInt();
            
            //validation
            boolean validRow = false;
            if(row <= board.length && row > 0)
            {
                validRow = true;
            }
            
            boolean validCol = false;
            if(validRow)
            {
                if(col <= board[row-1].length && col > 0)
                {
                    validCol = true;
                }
            }
            
            if(validRow && validCol)
            {
                if(board[row-1][col-1] == EMPTY)
                {
                    validMove = true;
                }
                else
                {
                    System.out.println("That square is already occupied by " + board[row-1][col-1]);
                }
            }
            else
            {
                if(!validRow)
                {
                    System.out.println("Hey bro.... invalid row");
                }
                else if(!validCol)
                {
                    System.out.println("Hey man.... invalid col");
                }
            }
            
        }
        
        //update board
        board[row-1][col-1] = whosTurn;
        //flip whos turn it is
        whosTurn = (whosTurn == X) ? O : X;
    }
    
    public String result()
    {
        return result;
    }
}