public virtual bool HasAnyValidMoves(BoardPosition from)
{
ChessUtility.ThrowIfNull(from, "from");
ReadOnlyCollection <Move> validMoves = GetValidMoves(from, true);
return(validMoves.Count > 0);
}
protected virtual bool IsValidMove(Move move, bool validateCheck, bool careAboutWhoseTurnItIs)
{
ChessUtility.ThrowIfNull(move, "move");
if (move.OriginalPosition.Equals(move.NewPosition))
{
return(false);
}
ChessPiece piece = GetPieceAt(move.OriginalPosition.File, move.OriginalPosition.Rank);
if (careAboutWhoseTurnItIs && move.Player != WhoseTurn)
{
return(false);
}
if (piece == null || piece.Owner != move.Player)
{
return(false);
}
ChessPiece pieceAtDestination = GetPieceAt(move.NewPosition);
if (pieceAtDestination != null && pieceAtDestination.Owner == move.Player)
{
return(false);
}
if (!piece.IsLegalMove(move, this))
{
return(false);
}
if (validateCheck && WouldBeInCheckAfter(move, move.Player))
{
return(false);
}
return(true);
}
public virtual bool WouldBeInCheckAfter(Move move, ChessPlayer player)
{
ChessUtility.ThrowIfNull(move, "move");
GameCreationData gcd = new GameCreationData
{
Board = Board,
CanWhiteCastleKingSide = CanWhiteCastleKingSide,
CanWhiteCastleQueenSide = CanWhiteCastleQueenSide,
CanBlackCastleKingSide = CanBlackCastleKingSide,
CanBlackCastleQueenSide = CanBlackCastleQueenSide,
EnPassant = null
};
if (_moves.Count > 0)
{
DetailedMove last = _moves.Last();
if (last.Piece is Pawn && new BoardDistance(last.OriginalPosition, last.NewPosition).Y == 2)
{
gcd.EnPassant = new BoardPosition(last.NewPosition.File, last.Player == ChessPlayer.White ? 3 : 6);
}
}
gcd.HalfMoveClock = _halfMoveClock;
gcd.FullMoveNumber = _fullMoveNumber;
ChessGame copy = new ChessGame(gcd);
copy.ApplyMove(move, true);
return(copy.IsInCheck(player));
}
protected virtual void UseGameCreationData(GameCreationData data)
{
Board = CloneBoard(data.Board);
WhoseTurn = data.WhoseTurn;
ChessPiece e1 = GetPieceAt(ChessFile.E, 1);
ChessPiece e8 = GetPieceAt(ChessFile.E, 8);
ChessPiece a1 = GetPieceAt(ChessFile.A, 1);
ChessPiece h1 = GetPieceAt(ChessFile.H, 1);
ChessPiece a8 = GetPieceAt(ChessFile.A, 8);
ChessPiece h8 = GetPieceAt(ChessFile.H, 8);
CanBlackCastleKingSide = CanBlackCastleQueenSide = CanWhiteCastleKingSide = CanWhiteCastleQueenSide = CastlingCanBeLegal;
if (CastlingCanBeLegal)
{
if (!(e1 is King) || e1.Owner != ChessPlayer.White)
{
CanWhiteCastleKingSide = CanWhiteCastleQueenSide = false;
}
if (!(e8 is King) || e8.Owner != ChessPlayer.Black)
{
CanBlackCastleKingSide = CanBlackCastleQueenSide = false;
}
if (!(a1 is Rook) || a1.Owner != ChessPlayer.White || !data.CanWhiteCastleQueenSide)
{
CanWhiteCastleQueenSide = false;
}
if (!(h1 is Rook) || h1.Owner != ChessPlayer.White || !data.CanWhiteCastleKingSide)
{
CanWhiteCastleKingSide = false;
}
if (!(a8 is Rook) || a8.Owner != ChessPlayer.Black || !data.CanBlackCastleQueenSide)
{
CanBlackCastleQueenSide = false;
}
if (!(h8 is Rook) || h8.Owner != ChessPlayer.Black || !data.CanBlackCastleKingSide)
{
CanBlackCastleKingSide = false;
}
}
if (data.EnPassant != null)
{
DetailedMove latestMove = new DetailedMove(new Move(new BoardPosition(data.EnPassant.File, data.WhoseTurn == ChessPlayer.White ? 7 : 2),
new BoardPosition(data.EnPassant.File, data.WhoseTurn == ChessPlayer.White ? 5 : 4),
ChessUtility.GetOpponentOf(data.WhoseTurn)),
new Pawn(ChessUtility.GetOpponentOf(data.WhoseTurn)),
false,
CastlingType.None);
_moves.Add(latestMove);
}
_halfMoveClock = data.HalfMoveClock;
_fullMoveNumber = data.FullMoveNumber;
}
protected static ChessPiece[][] CloneBoard(ChessPiece[][] originalBoard)
{
ChessUtility.ThrowIfNull(originalBoard, "originalBoard");
ChessPiece[][] newBoard = new ChessPiece[originalBoard.Length][];
for (int i = 0; i < originalBoard.Length; i++)
{
newBoard[i] = new ChessPiece[originalBoard[i].Length];
Array.Copy(originalBoard[i], newBoard[i], originalBoard[i].Length);
}
return(newBoard);
}
protected virtual ReadOnlyCollection <Move> GetValidMoves(BoardPosition from, bool returnIfAny)
{
ChessUtility.ThrowIfNull(from, "from");
ChessPiece piece = GetPieceAt(from);
if (piece == null || piece.Owner != WhoseTurn)
{
return(new ReadOnlyCollection <Move>(new List <Move>()));
}
return(piece.GetLegalMoves(from, returnIfAny, this, IsValidMove));
}
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 override ReadOnlyCollection <Move> GetLegalMoves(BoardPosition from, bool returnIfAny, ChessGame game, Func <Move, bool> gameMoveValidator)
{
ChessUtility.ThrowIfNull(from, "from");
List <Move> validMoves = new List <Move>();
ChessPiece piece = game.GetPieceAt(from);
int l0 = game.BoardHeight;
int l1 = game.BoardWidth;
for (int i = -7; i < 8; i++)
{
if (i == 0)
{
continue;
}
if (from.Rank + i > 0 && from.Rank + i <= l0)
{
Move move = new Move(from, new BoardPosition(from.File, from.Rank + i), piece.Owner);
if (gameMoveValidator(move))
{
validMoves.Add(move);
if (returnIfAny)
{
return(new ReadOnlyCollection <Move>(validMoves));
}
}
}
if ((int)from.File + i > -1 && (int)from.File + i < l1)
{
Move move = new Move(from, new BoardPosition(from.File + i, from.Rank), piece.Owner);
if (gameMoveValidator(move))
{
validMoves.Add(move);
if (returnIfAny)
{
return(new ReadOnlyCollection <Move>(validMoves));
}
}
}
}
return(new ReadOnlyCollection <Move>(validMoves));
}
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);
}
protected bool IsValidMove(Move move, bool validateCheck)
{
ChessUtility.ThrowIfNull(move, "move");
return(IsValidMove(move, validateCheck, true));
}
public bool IsValidMove(Move move)
{
ChessUtility.ThrowIfNull(move, "move");
return(IsValidMove(move, true, true));
}
public ChessPiece GetPieceAt(BoardPosition position)
{
ChessUtility.ThrowIfNull(position, "position");
return(GetPieceAt(position.File, position.Rank));
}
public virtual bool IsWinner(ChessPlayer player)
{
return(IsCheckmated(ChessUtility.GetOpponentOf(player)));
}
public ReadOnlyCollection <Move> GetValidMoves(BoardPosition from)
{
ChessUtility.ThrowIfNull(from, "from");
return(GetValidMoves(from, false));
}