File indexing completed on 2024-04-28 04:05:21

 /*
     SPDX-FileCopyrightText: 2015 Jakob Gruber <jakob.gruber@gmail.com>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #ifndef BOARDSTATE_H
 #define BOARDSTATE_H
 
 #include <QObject>
 #include <QPoint>
 #include <QStack>
 #include <QSharedPointer>
 
 #include "board.h"
 
 class BoardState : public QObject, public Board
 {
     Q_OBJECT
 public:
     /* initializes an empty field of given width and height,
       and creates initial (empty) streaks.
       width, height > 0 */
     BoardState(int width, int height);
 
     /* 0 <= x < m_width; 0 <= y < m_height
       sets point (x, y) to state */
     void set(int x, int y, enum State state);
 
     /* undo the last stored action and return the changed coordinate.
        if none are left, nothing occurs and QPoint() is returned*/
     QPoint undo();
 
     /* save the current state and push it onto the state stack. */
     void saveState();
 
     /* pop and load a state if state stack is non-empty.
        otherwise, do nothing */
     void loadState();
 
     /* returns the age (in steps) of the current game state
        compared to the latest saved state. for example, if the
        current undo_queue.size() == 15, and the top of saved_states
        is 10, currentStateAge returns 5. */
     int currentStateAge() const;
 
     /* returns the count of player-set boxes */
     int boxCount() const { return m_box_count; }
 
     /* replaces all occurrences of prev with next.
        bookkeeping information (undo history, box count) is _not_ updated */
     void replace(enum State prev, enum State next);
 
     /* Copies the board to this state. Like replace(), bookkeeping
        information is not updated since this is the final action in a game. */
     void solve(const Board *board);
 
 Q_SIGNALS:
     void undoStackSizeChanged(int size);
     void saveStackSizeChanged(int size);
 
 private:
 
     /* updates the box count according to old state prev and incoming state next. */
     void updateBoxCount(Board::State prev, Board::State next);
 
 private:
 
     struct UndoAction {
         int x, y;
         enum State state;
     };
 
     QStack<UndoAction> m_undo_queue;
     QStack<int> m_saved_states;     /* size of m_undo_queue when state was saved */
 
     int m_box_count;
 };
 
 #endif // BOARDSTATE_H