othello.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *
 * This file is dual-licensed.
 * In addition to the GPLv3 license mentioned above, MojoTouch has exclusively licensed
 * this code on November 10th, 2021, to be use in closed-source products.
 * Therefore, any contributions (commits) to it will also be dual-licensed.
 *
 */

#ifndef GROOVIE_LOGIC_OTHELLO_H
#define GROOVIE_LOGIC_OTHELLO_H

#include "common/random.h"
#include "common/system.h"

namespace Groovie {

/*
 * Othello/Reversi Cursed Coins puzzle in Clandestiny and UHP.
 */
struct Freeboard {
    int _score;
    byte _boardstate[8][8]; // 0 is empty, 1 is player, 2 is AI

    // for sorting an array of pointers
    friend bool operator<(const Freeboard &a, const Freeboard &b) {
        return a._score > b._score;
    }
};

class OthelloGame {
public:
    OthelloGame(bool easierAi);
    void run(byte *scriptVariables);

private:
    int scoreEdge(byte (&board)[8][8], int x, int y, int slopeX, int slopeY);
    int scoreEarlyGame(Freeboard *freeboard);
    int scoreLateGame(Freeboard *freeboard);
    int scoreBoard(Freeboard *board);
    void restart(void);
    void writeBoardToVars(Freeboard *board, byte *vars);
    void readBoardStateFromVars(byte *vars);
    Freeboard getPossibleMove(Freeboard *freeboard, int moveSpot);
    void checkPossibleMove(Freeboard *board, Freeboard (&boards)[30], int8 **lineSpot, int &numPossibleMoves, int moveSpot, byte player, byte opponent);
    int getAllPossibleMoves(Freeboard *board, Freeboard (&boards)[30]);
    int aiRecurse(Freeboard *board, int depth, int parentScore, int opponentBestScore);
    byte aiDoBestMove(Freeboard *pBoard);
    void initLines(void);
    uint makeMove(Freeboard *freeboard, uint8 x, uint8 y);
    byte getLeader(Freeboard *f);
    void opInit(byte *vars);
    void tickBoard();
    void opPlayerMove(byte *vars);
    void op3(byte *vars);
    void opAiMove(byte *vars);
    void op5(byte *vars);

    void test();
    void testMatch(Common::Array<int> moves, bool playerWin);

    Common::RandomSource _random;
    byte _flag1;
    int8 _flag2;
    const int _depths[60];
    int _counter;
    const int _movesLateGame;    // this is 52, seems to be a marker of when to change the function pointer to an aleternate scoring algorithm for the late game
    bool _isLateGame;      // used to choose the scoring function, true means scoreLateGame
    const int8 _lookupPlayer[3]; // used to convert from internal values that represent piece colors to what the script uses in vars, {21, 40, 31}
    const int8 _scores[3][4];
    const int8 _edgesScores[112];
    const int _cornersScores[105];
    int _isAiTurn;
    int8 **_lines[64];
    int8 *_linesStorage[484];
    int8 _lineStorage[2016];
    Freeboard _board;
    bool _easierAi;
};

} // End of Groovie namespace

#endif // GROOVIE_LOGIC_OTHELLO_H