[CareerCup] 8.8 Othello Game 黑白棋游戏

enum Direction { Left, Right, Up, Down };
enum Color { White, Black };
class Piece {
public:
    Piece(Color c): _color(c) {}
    void flip() {
        if (_color == Color::Black) _color = Color::White;
        else _color = Color::Black;
    }
    Color getColor() { return _color; }

private:
    Color _color;
};

class Location {
public:
    Location(int r, int c): _row(r), _col(c) {}
    bool isSameAs(int r, int c) {
        return _row == r && _col == c;
    }
    int getRow() { return _row; }
    int getCol() { return _col; }
    
private:
    int _row;
    int _col;
};

class Board {
public:
    Board(int rows, int cols) {
        _board.resize(rows, vector<Piece*>(cols));
    }
    void initialize() {
        int midRow = _board.size() / 2;
        int midCol = _board[midRow].size() / 2;
        _board[midRow][midCol] = new Piece(Color::White);
        _board[midRow + 1][midCol] = new Piece(Color::Black);
        _board[midRow + 1][midCol + 1] = new Piece(Color::White);
        _board[midRow][midCol + 1] = new Piece(Color::Black);
        _blackCnt = 2;
        _whiteCnt = 2;
    } 
    bool placeColor(int row, int col, Color color) {
        if (_board[row][col] != nullptr) {
            return false;
        }
        vector<int> res(4, 0);
        res[0] = flipSection(row - 1, col, color, Direction::Up);
        res[1] = flipSection(row + 1, col, color, Direction::Down);
        res[2] = flipSection(row, col + 1, color, Direction::Right);
        res[3] = flipSection(row, col - 1, color, Direction::Left);
        int flipped = 0;
        for (auto a : res) {
            if (a > 0) flipped += a;
        }
        if (flipped < 0) return false;
        _board[row][col] = new Piece(color);
        updateScore(color, flipped + 1);
        return true;
    } 
    int getScoreForColor(Color c) {
        if (c == Color::Black) return _blackCnt;
        else return _whiteCnt;
    }
    void updateScore(Color newColor, int newPieces) {
        if (newColor == Color::Black) {
            _whiteCnt -= newPieces - 1;
            _blackCnt += newPieces;
        } else {
            _blackCnt -= newPieces - 1;
            _whiteCnt += newPieces;
        }
    } 
    void printBoard() {
        for (int r = 0; r < _board.size(); ++r) {
            for (int c = 0; c < _board[r].size(); ++c) {
                if (_board[r][c] == nullptr) {
                    cout << "_";
                } else if (_board[r][c]->getColor() == Color::White) {
                    cout << "W";
                } else {
                    cout << "B";
                }
            }
            cout << endl;
        }
    }

private:
    int _blackCnt = 0;
    int _whiteCnt = 0;
    vector<vector<Piece*> > _board;
    int flipSection(int row, int col, Color color, Direction d) {
        int r = 0, c = 0;
        switch (d) {
            case Direction::Up: r = -1; break;
            case Direction::Down: r = 1; break;
            case Direction::Left: c = -1; break;
            case Direction::Right: c = 1; break;
        }
        if (row < 0 || row >= _board.size() || col < 0 || col >= _board[row].size() || _board[row][col] == nullptr) {
            return -1;
        }
        if (_board[row][col]->getColor() == color) {
            return 0;
        }
        int flipped = flipSection(row + r, col + c, color, d);
        if (flipped < 0) return -1;
        _board[row][col]->flip();
        return flipped + 1;
    } 
};

class Player {
public:
    Player(Color c): _color(c) {}
    int getScore() {
    
    } // ...
    bool playPiece(int r, int c) {
        return Game::getInstance()->getBoard()->placeColor(r, c, _color);
    }

private:
    Color _color;
};

class Game {
public:
    static Game* getInstance() {
        if (_instance == nullptr) {
            _instance = new Game();
        }
        return _instance;
    }
    Board* getBoard() { return _board; }

private:
    vector<Player*> _players;
    static Game *_instance;
    Board *_board;
    const int _ROWS = 10;
    const int _COLUMNS = 10;
    Game() {
        _board = new Board(_ROWS, _COLUMNS);
        _players.resize(2, nullptr);
        _players[0] = new Player(Color::Black);
        _players[1] = new Player(Color::White);
    }
};