private void ApplyMove(ChessMove move)
{
bool isBlack = PieceColorAt(move.Source) == PieceColor.Black;
if (IsBlacksTurn)
{
if (!isBlack)
throw new InvalidOperationException("Attempted to move a white piece on black's turn");
}
else
{
if (isBlack)
throw new InvalidOperationException("Attempted to move a black piece on white's turn");
}
switch (this[move.Source] & ChessPiece.PieceMask)
{
case ChessPiece.Pawn:
if ((move.Source.col != move.Target.col) && ((this[move.Target] & ChessPiece.PieceMask) == ChessPiece.Empty))
{
// En Passant
if (isBlack)
board[move.Target.row - 1, move.Target.col] = ChessPiece.Empty;
else
board[move.Target.row + 1, move.Target.col] = ChessPiece.Empty;
}
if ((move.Target.row - move.Source.row > 1) || (move.Source.row - move.Target.row > 1))
pawnJumpCol = move.Source.col;
else
pawnJumpCol = 99;
break;
case ChessPiece.Rook:
if (move.Source.col == 0)
flags |= BoardFlags.WhiteQueenSideCastlingEnded;
else flags |= BoardFlags.WhiteKingSideCastlingEnded;
pawnJumpCol = 99;
break;
case ChessPiece.BlackRook:
if (move.Source.col == 0)
flags |= BoardFlags.BlackQueenSideCastlingEnded;
else flags |= BoardFlags.BlackKingSideCastlingEnded;
pawnJumpCol = 99;
break;
case ChessPiece.King:
if (isBlack)
flags |= BoardFlags.BlackKingSideCastlingEnded | BoardFlags.BlackQueenSideCastlingEnded;
else
flags |= BoardFlags.WhiteKingSideCastlingEnded | BoardFlags.WhiteQueenSideCastlingEnded;
if (move.Target.col - move.Source.col > 1)
{
// Castling to king's rook
board[move.Source.row, 5] = board[move.Source.row, 7];
board[move.Source.row, 7] = ChessPiece.Empty;
}
else if (move.Source.col - move.Target.col > 1)
{
// Castling to queen's rook
board[move.Source.row, 3] = board[move.Source.row, 0];
board[move.Source.row, 0] = ChessPiece.Empty;
}
pawnJumpCol = 99;
break;
case ChessPiece.Empty:
throw new InvalidOperationException("Attempted to move from a square without a piece.");
default:
pawnJumpCol = 99;
break;
}
if ((isBlack && (move.Target.row == 7) && (board[move.Source.row, move.Source.col] == ChessPiece.BlackPawn))
|| (!isBlack && (move.Target.row == 0) && (board[move.Source.row, move.Source.col] == ChessPiece.Pawn)))
board[move.Target.row, move.Target.col] = move.Promotion | (isBlack ? ChessPiece.Black : 0);
else
board[move.Target.row, move.Target.col] = board[move.Source.row, move.Source.col];
board[move.Source.row, move.Source.col] = ChessPiece.Empty;
flags ^= BoardFlags.BlacksTurn;
CheckForCheck();
}
public ChessBoard Move(ChessMove move)
{
ChessBoard result;
if (moveResults == null)
GetValidMoves();
if (moveResults.TryGetValue(move, out result))
{
if (result == null)
{
result = Clone();
result.ApplyMove(move);
}
moveResults[move] = result;
return result;
}
throw new ArgumentException(string.Format("{0} is not a valid move.", move));
}
public EvaluatedMove(ChessMove move, ChessBoard resultingState, EvaluatedMove predecessor = null)
{
this.move = move;
this.resultingState = resultingState;
this.Previous = predecessor;
}
public IEnumerable<ChessMove> GetValidMoves()
{
if (moveResults == null)
{
moveResults = new Dictionary<ChessMove, ChessBoard>();
for (int row = 0; row < 8; row++)
for (int col = 0; col < 8; col++)
{
Coordinate source = new Coordinate(row, col);
if ((IsBlacksTurn && (PieceColorAt(source) == PieceColor.Black))
|| (!IsBlacksTurn && (PieceColorAt(source) == PieceColor.White)))
{
foreach (Coordinate target in GetMovesForPiece(source))
{
if (((this[source] == ChessPiece.Pawn) && (target.row == 0))
|| ((this[source] == ChessPiece.BlackPawn) && (target.row == 7)))
{
bool bFirstPromotion = true;
foreach (ChessPiece promotion in new ChessPiece[] { ChessPiece.Rook, ChessPiece.Knight, ChessPiece.Bishop, ChessPiece.Queen })
{
ChessBoard clone = Clone();
ChessMove move = new ChessMove(source, target, promotion);
clone.ApplyMove(move);
if (bFirstPromotion && ((IsBlacksTurn && clone.IsBlackInCheck) || (!IsBlacksTurn && clone.IsWhiteInCheck)))
break;
bFirstPromotion = false;
moveResults[move] = clone;
}
}
else
{
ChessBoard clone = Clone();
ChessMove move = new ChessMove(source, target);
clone.ApplyMove(move);
if (((IsBlacksTurn && !clone.IsBlackInCheck) || (!IsBlacksTurn && !clone.IsWhiteInCheck)))
moveResults[move] = clone;
}
}
}
}
}
return moveResults.Keys;
}
public EvaluatedMove(ChessMove move, ChessBoard resultingState, EvaluatedMove predecessor = null)
{
this.move = move;
this.resultingState = resultingState;
this.Previous = predecessor;
}