/// <summary>
/// Updates what types of castling is possible after the move has been performed.
/// </summary>
/// <param name="afterState">The "BoardState" to update.</param>
protected void SetCastlingAvailabilety(ref BoardState afterState)
{
switch (m_from)
{
case Square.E1:
afterState.WhiteCanCastleLong = false;
afterState.WhiteCanCastleShort = false;
break;
case Square.E8:
afterState.BlackCanCastleLong = false;
afterState.BlackCanCastleShort = false;
break;
case Square.A1:
afterState.WhiteCanCastleLong = false;
break;
case Square.A8:
afterState.BlackCanCastleLong = false;
break;
case Square.H1:
afterState.WhiteCanCastleShort = false;
break;
case Square.H8:
afterState.BlackCanCastleShort = false;
break;
}
switch (m_to)
{
case Square.A1:
afterState.WhiteCanCastleLong = false;
break;
case Square.A8:
afterState.BlackCanCastleLong = false;
break;
case Square.H1:
afterState.WhiteCanCastleShort = false;
break;
case Square.H8:
afterState.BlackCanCastleShort = false;
break;
}
}
/// <summary>
/// Updates if the board has a pawn that can be hit En-Passant after the move has been performed.
/// </summary>
/// <param name="afterState">The "BoardState" to update.</param>
protected void SetEnPassentTarget(ref BoardState afterState)
{
if ((Board.Rank(m_from) == 1 && Board.Rank(m_to) == 3 && m_piece == Piece.WhitePawn) ||
(Board.Rank(m_from) == 6 && Board.Rank(m_to) == 4 && m_piece == Piece.BlackPawn))
{
afterState.EnPassantTarget = m_to;
}
else
{
afterState.EnPassantTarget = Square.None;
}
}
/// <summary>
/// Updates the board state as a result of a move has been performed.
/// </summary>
/// <param name="afterState">The "BoardState" to update.</param>
protected void EndTurn(ref BoardState afterState)
{
if (m_capture != Piece.None || m_piece == Piece.WhitePawn || m_piece == Piece.BlackPawn)
afterState.NonHitAndPawnMovesPlayed = 0;
else
afterState.NonHitAndPawnMovesPlayed++;
switch (m_beforeState.ColorToPlay)
{
case PieceColor.White:
afterState.ColorToPlay = PieceColor.Black;
break;
case PieceColor.Black:
afterState.ColorToPlay = PieceColor.White;
break;
}
}
/// <summary>
/// Performs the move. I move is only pseudo legal (putting own king in check)
/// the move isn't executed.
/// </summary>
/// <returns>True if move could be carried out, false otherwise.</returns>
public virtual bool Execute()
{
BoardState afterState = m_beforeState = m_board.State;
m_board.MovePiece(m_from, m_to);
SetCastlingAvailabilety(ref afterState);
SetEnPassentTarget(ref afterState);
EndTurn(ref afterState);
m_board.State = afterState;
m_board.AddToHistory();
if (m_board.IsCheck(m_beforeState.ColorToPlay))
{
UnExecute();
return false;
}
return true;
}
public Board(Board board)
{
m_squares = new Piece[board.m_squares.Length];
for (int i = 0; i < m_squares.Length; ++i)
m_squares[i] = board.m_squares[i];
m_state = board.m_state;
m_history = new HashHistory(board.m_history);
m_pieceFactory = FlyweightPieceFactory.Instance();
m_whiteLocationList = new PieceLocationManager(board.m_whiteLocationList);
m_blackLocationList = new PieceLocationManager(board.BlackPieceLocations);
m_whiteKingLocation = board.m_whiteKingLocation;
m_blackKingLocation = board.m_blackKingLocation;
m_boardHash = new ZobristHash(board.m_boardHash);
}
/// <summary>
/// Performs the move. If move is only pseudo legal (putting own king in check)
/// the move isn't executed.
/// </summary>
/// <returns>True if move could be carried out, false otherwise.</returns>
private bool StandardExecute(Board board)
{
BoardState afterState = m_beforeState = board.State;
board.MovePiece(m_from, m_to);
SetCastlingAvailabilety(ref afterState);
SetEnPassentTarget(ref afterState);
EndTurn(ref afterState);
board.State = afterState;
board.AddToHistory();
if (board.IsCheck(m_beforeState.ColorToPlay))
{
StandardUnExecute(board);
return false;
}
return true;
}
/// <summary>
/// Updates if the board has a pawn that can be hit En-Passant after the move has been performed.
/// </summary>
/// <param name="afterState">The "BoardState" to update.</param>
private void SetEnPassentTarget(ref BoardState afterState)
{
if ((Board.Rank(From) == 1 && Board.Rank(To) == 3 && Piece == Piece.WhitePawn) ||
(Board.Rank(From) == 6 && Board.Rank(To) == 4 && Piece == Piece.BlackPawn))
{
afterState.EnPassantTarget = To;
}
else
{
afterState.EnPassantTarget = Square.None;
}
}