public override bool Equals(object obj)
{
if (obj == null || GetType() != obj.GetType())
{
return(false);
}
BoardDistance distance = (BoardDistance)obj;
return(X == distance.X && Y == distance.Y);
}
public override bool IsLegalMove(Move move, ChessGame game)
{
ChessUtility.ThrowIfNull(move, "move");
ChessUtility.ThrowIfNull(game, "game");
BoardPosition origin = move.OriginalPosition;
BoardPosition destination = move.NewPosition;
BoardDistance posDelta = new BoardDistance(origin, destination);
if (posDelta.X != 0 && posDelta.Y != 0)
{
return(false);
}
bool increasingRank = destination.Rank > origin.Rank;
bool increasingFile = (int)destination.File > (int)origin.File;
if (posDelta.X == 0)
{
int f = (int)origin.File;
for (int r = origin.Rank + (increasingRank ? 1 : -1);
increasingRank?r <destination.Rank : r> destination.Rank;
r += increasingRank ? 1 : -1)
{
if (game.GetPieceAt((ChessFile)f, r) != null)
{
return(false);
}
}
}
else // (posDelta.DeltaY == 0)
{
int r = origin.Rank;
for (int f = (int)origin.File + (increasingFile ? 1 : -1);
increasingFile?f <(int)destination.File : f> (int) destination.File;
f += increasingFile ? 1 : -1)
{
if (game.GetPieceAt((ChessFile)f, r) != null)
{
return(false);
}
}
}
return(true);
}
public virtual MoveType ApplyMove(Move move, bool alreadyValidated)
{
ChessUtility.ThrowIfNull(move, "move");
if (!alreadyValidated && !IsValidMove(move))
{
return(MoveType.Invalid);
}
MoveType type = MoveType.Move;
ChessPiece movingPiece = GetPieceAt(move.OriginalPosition.File, move.OriginalPosition.Rank);
ChessPiece capturedPiece = GetPieceAt(move.NewPosition.File, move.NewPosition.Rank);
ChessPiece newPiece = movingPiece;
bool isCapture = capturedPiece != null;
CastlingType castle = CastlingType.None;
if (movingPiece is Pawn)
{
_halfMoveClock = 0;
BoardDistance pd = new BoardDistance(move.OriginalPosition, move.NewPosition);
if (pd.X == 1 && pd.Y == 1 && GetPieceAt(move.NewPosition) == null)
{ // en passant
isCapture = true;
SetPieceAt(move.NewPosition.File, move.OriginalPosition.Rank, null);
}
if (move.NewPosition.Rank == (move.Player == ChessPlayer.White ? 8 : 1))
{
newPiece = MapPgnCharToPiece(move.Promotion.Value, move.Player);
type |= MoveType.Promotion;
}
}
else if (movingPiece is King)
{
if (movingPiece.Owner == ChessPlayer.White)
{
CanWhiteCastleKingSide = CanWhiteCastleQueenSide = false;
}
else
{
CanBlackCastleKingSide = CanBlackCastleQueenSide = false;
}
if (new BoardDistance(move.OriginalPosition, move.NewPosition).X == 2 && CastlingCanBeLegal)
{
castle = ApplyCastle(move);
type |= MoveType.Castling;
}
}
else if (movingPiece is Rook)
{
if (move.Player == ChessPlayer.White)
{
if (move.OriginalPosition.File == ChessFile.A && move.OriginalPosition.Rank == 1)
{
CanWhiteCastleQueenSide = false;
}
else if (move.OriginalPosition.File == ChessFile.H && move.OriginalPosition.Rank == 1)
{
CanWhiteCastleKingSide = false;
}
}
else
{
if (move.OriginalPosition.File == ChessFile.A && move.OriginalPosition.Rank == 8)
{
CanBlackCastleQueenSide = false;
}
else if (move.OriginalPosition.File == ChessFile.H && move.OriginalPosition.Rank == 8)
{
CanBlackCastleKingSide = false;
}
}
}
if (isCapture)
{
type |= MoveType.Capture;
_halfMoveClock = 0;
if (move.NewPosition.File == ChessFile.A && move.NewPosition.Rank == 1)
{
CanWhiteCastleQueenSide = false;
}
else if (move.NewPosition.File == ChessFile.H && move.NewPosition.Rank == 1)
{
CanWhiteCastleKingSide = false;
}
else if (move.NewPosition.File == ChessFile.A && move.NewPosition.Rank == 8)
{
CanBlackCastleQueenSide = false;
}
else if (move.NewPosition.File == ChessFile.H && move.NewPosition.Rank == 8)
{
CanBlackCastleKingSide = false;
}
}
if (!isCapture && !(movingPiece is Pawn))
{
_halfMoveClock++;
if (_halfMoveClock >= 100)
{
fiftyMoves = true;
}
else
{
fiftyMoves = false;
}
}
if (move.Player == ChessPlayer.Black)
{
_fullMoveNumber++;
}
SetPieceAt(move.NewPosition.File, move.NewPosition.Rank, newPiece);
SetPieceAt(move.OriginalPosition.File, move.OriginalPosition.Rank, null);
WhoseTurn = ChessUtility.GetOpponentOf(move.Player);
_moves.Add(new DetailedMove(move, movingPiece, isCapture, castle));
_positions.Add(GetPosition());
return(type);
}