/* Yo Emacs, this -*- C++ -*-
 *******************************************************************
 *******************************************************************
 *
 *
 * KREVERSI
 *
 *
 *******************************************************************
 *
 * A Reversi (or sometimes called Othello) game
 *
 *******************************************************************
 *
 * Created 1997 by Mario Weilguni <mweilguni@sime.com>. This file
 * is ported from Mats Luthman's <Mats.Luthman@sylog.se> JAVA applet.
 * Many thanks to Mr. Luthman who has allowed me to put this port
 * under the GNU GPL. Without his wonderful game engine kreversi
 * would be just another of those Reversi programs a five year old
 * child could beat easily. But with it it's a worthy opponent!
 *
 * If you are interested on the JAVA applet of Mr. Luthman take a
 * look at http://www.sylog.se/~mats/
 *
 *******************************************************************
 *
 * This file is part of the KDE project "KREVERSI"
 *
 * KREVERSI 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 2, or (at your option)
 * any later version.
 *
 * KREVERSI 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 KREVERSI; see the file COPYING.  If not, write to
 * the Free Software Foundation, 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 *******************************************************************
 */

// The class Game represents a complete or incomplete Othello game. It uses
// the classes Score and Move (and internally  Position).
// You can make moves, take back one move at a time, reset to initial position
// and get certain data on the current position.

//  Public functions:

//  public Game()
//     Creates a game with the initial position.

//  public void Reset()
//     Resets to the initial position.

//  public boolean MakeMove(Move m)
//     Makes the move m. Returns false if the move is not legal or when called
//     with a move where the player is Score.NOBODY.

//  public boolean TakeBackMove()
//     Takes back a move. Returns true if not at the initial position.

//  public int GetSquare(int x, int y)
//     Returns the piece at (x, y). Returns Score.NOBODY if the square is not
//     occupied.

//  public int GetScore(int player)
//     Returns the score for player.

//  public Move GetLastMove()
//     Returns the last move. Returns null if at the initial position.

//  public boolean MoveIsLegal(Move m)
//     Checks if move m is legal.

//  public boolean MoveIsPossible(int player)
//     Checks if there is a legal move for player.

//  public boolean MoveIsAtAllPossible()
//     Checks if there are any legal moves at all.

//  public int GetMoveNumber()
//     Returns move number.

//  public int GetWhoseTurn()
//     Returns the player in turn to play (if there are no legal moves
//     Score.NOBODY is returned).

//  public Move[] TurnedByLastMove()
//     Returns a vector of the squares that were changed by the last move.
//     The move that was actually played is at index 0. At the initial
//     position the length of the vector returned is zero. (Could be used
//     for faster updates of a graphical board).


#include "Game.h"

Game::Game()
{
  m_positions[0].constrInit();
  m_movenumber = 0;
}

void Game::Reset()
{
  m_positions[0].constrInit();
  m_movenumber = 0;
}


bool Game::MakeMove(Move m)
{
  if (m.player() == Nobody) return false;
  if (whoseTurn() != m.player()) return false;
  if (! m_positions[m_movenumber].moveIsLegal(m)) return false;

  m_positions[m_movenumber+1].constrCopy(m_positions[m_movenumber], m);
  m_movenumber++;

  return true;
}


bool Game::TakeBackMove()
{
  if (m_movenumber == 0) return false;

  m_movenumber--;

  return true;
}


Player Game::player(uint x, uint y) const
{
  return m_positions[m_movenumber].player(x, y);
}


uint Game::score(Player player) const
{
  return m_positions[m_movenumber].score(player);
}


Move Game::lastMove() const { return m_positions[m_movenumber].lastMove(); }


bool Game::moveIsLegal(Move m) const
{
  return m_positions[m_movenumber].moveIsLegal(m);
}


bool Game::moveIsPossible(Player player) const
{
  return m_positions[m_movenumber].moveIsPossible(player);
}


bool Game::moveIsAtAllPossible() const
{
  return m_positions[m_movenumber].moveIsAtAllPossible();
}


Player Game::whoseTurn() const
{
  if (m_movenumber == 0) return Black;

  Player player = lastMove().player();
  Player opponent = ::opponent(player);

  if (moveIsPossible(opponent)) return opponent;
  if (moveIsPossible(player)) return player;
  return Nobody;
}

bool Game::squareModified(uint x, uint y) const {
  if(moveNumber() == 0)
    return true;
  else
    return (m_positions[m_movenumber].player(x, y) != m_positions[m_movenumber-1].player(x, y));
}

bool Game::wasTurned(uint x, uint y) const {
  if(moveNumber() == 0)
    return false;
  else {
    Player c1 = m_positions[m_movenumber-1].player(x, y);
    Player c2 = m_positions[m_movenumber].player(x, y);

    if(c1 == Nobody)
      return false;
    else if(c1 == c2)
      return false;
    else
      return true;
  }
}