package tictactoe;

import java.util.Scanner;

/**
 * Tic Tac Toe The user ('X') plays against the computer ('O') The first player
 * is chosen randomly.
 *
 * @author gorr
 */
public class TicTacToe {

    /**
     * the game character symbol for the player
     */
    private static final char PLAYER = 'X';
    /**
     * the game character symbol for the computer
     */
    private static final char COMPUTER = 'O';
    /**
     * the game character symbol for an empty place on the board
     */
    private static final char EMPTY = '-';

    /**
     * the current board
     */
    // !!!!!! DECLARE BOARD HERE
    /**
     * the current player
     */
    private char currentPlayer;
    
    /**
     * the winner
     */
    private char winner = ' ';

    /**
     * Use for reading input from the user
     */
    Scanner in = new Scanner(System.in);

    /**
     * Plays the game of TicTacToe. Stops when either 1) a player wins or 2) no
     * spaces are left on the board.
     */
    public void play() {

        openingGreeting(); // greeting

        currentPlayer = initPlayer();  // pick starting player     
        initBoard();   // initialize the board
        int moves = 0;
        boolean hasWon = false;
        while (moves < 9 && !hasWon) {      // game loop over moves and hasWon
            if (currentPlayer == PLAYER) {
                userTurn();
            } else {
                computerTurn();
            }
            System.out.println("The board is now: \n" + this);
            hasWon = checkWin();   // has the current player won?
            currentPlayer = swapPlayer();    // swap the currentPlayer
            moves++;
        }
        // !!!!!! CHECK TO SEE IF THERE IS WINNER. IF SO, SAY WHO.  
        // !!!!!! OTHERWISE, SAY THAT NO ONE HAS WON.

    }

    /**
     * Welcome the player
     */
    public void openingGreeting() {
        System.out.println("\nWELCOME TO TICTACTOE\n");
        System.out.println("You will be X, the computer will be O.");
        System.out.println("The starting player will be picked randomly.");
        System.out.println("Enjoy the game and good luck!\n");

    }

    /**
     * Initialize the values in the board to all blanks. Note, each board
     * position is either: PLAYER - this is the user COMPUTER - this is the
     * computer EMPTY - indicates the position is empty
     */
    public void initBoard() {
        // !!!!!! INITIALIZE BOARD HERE
    }

    /**
     * Swap the current player. That is, if the current player is 'X', it is
     * swapped to be 'O', and vice versa.
     *
     * @return the new current player
     */
    public char swapPlayer() {
        if (currentPlayer == PLAYER) {
            currentPlayer = COMPUTER;
        } else {
            currentPlayer = PLAYER;
        }
        return currentPlayer;
    }

    /**
     * Randomly pick which player (user or computer) goes first. Set the
     * currentPlayer to the first player. It is assumed that the user is always
     * "X" and the computer is always "O".
     *
     * @return the first player
     */
    public char initPlayer() {
        if (Math.random() < .5) {
            currentPlayer = PLAYER;
            System.out.println("You are the first player.");
        } else {
            currentPlayer = COMPUTER;
            System.out.println("The computer is the first player.");
        }
        return currentPlayer;
    }

    /**
     * Chooses which position the computer will play. Sets that position of the
     * board to "O"
     */
    public void computerTurn() {
        System.out.println("\nIt is the computer's turn. \n"
                + "Press enter to continue.");
        in.nextLine();  // reads in the uers's "enter"
        
        // !!!!!! DECIDE WHERE THE COMPUTER WILL PLAY
    }

    /**
     * Have the user choose which position to play. Sets that position of the
     * board to "X"
     */
    public void userTurn() {
        System.out.println("\nIt is your turn.");
        System.out.print("Enter the row (0-2) of your move: ");
        int row = readValue();
        System.out.println("You entered row " + row);
        System.out.print("Enter the column (0-2) of your move: ");
        int col = readValue();
        System.out.println("You entered column " + col);
        while (board[row][col] != EMPTY) {
            System.out.println("\nThis space is not empty. Try again entering a row & column.");
            System.out.print("Enter the row (0-2) of your move: ");
            row = readValue();
            System.out.println("You entered row " + row);
            System.out.print("Enter the column (0-2) of your move: ");
            col = readValue();
            System.out.println("You entered column " + col);
        }
        System.out.println("");
        board[row][col] = PLAYER;
    }

    /**
     * Utility method to prompt user for a value in the range of 0 to 2 It makes
     * sure that the user enters a number between 0 and 2. If not, it loops and
     * asks for another input.
     *
     * @return the value of the row or column
     */
    public int readValue() {
        int val = Integer.parseInt(in.nextLine().trim().substring(0,1));
        while (val < 0 || val > 2) {
            System.out.print("You have not entered a value in the "
                    + "range 0 to 2. Please try again: ");
            val = Integer.parseInt(in.nextLine().trim().substring(0,1));
        }
        return val;
    }

    /**
     * Checks to see if the currentPlayer has won. 
     *
     * @return true if the currentPlayer has won.
     */
    public boolean checkWin() {
        int cnt = 0; // counts the number of positions occupied by currentPlayer
        // check rows
        for (int i = 0; i < board.length; i++) {
            cnt = 0;
            for (int j = 0; j < board[i].length; j++) {
                if (board[i][j] == currentPlayer) {
                    cnt++;
                }
            }
            if (cnt == 3) {
                winner = currentPlayer;
                return true;
            }
        }

        // !!!!!! HERE YOU NEED TO CHECK THE COLUMNS AND DIAGONALS!
        
        
        
        return false;  // no one has won
    }

    /**
     * @return string representation of the board.
     */
    public String toString() {
        String b = "\t";
        // !!!!!! CREATE STRING REPRESENTATION OF THE BOARD
        return b;
    }
}