private Piece ExecuteMovement(Position origin, Position destination)
{
Piece pieceToMove = Board.RemovePieceFromBoard(origin);
pieceToMove.IncrementMovementQuantity();
Piece pieceToCapture = Board.RemovePieceFromBoard(destination);
if (pieceToCapture != null)
{
piecesCaptured.Add(pieceToCapture);
}
Board.AddPieceToBoard(pieceToMove, destination);
// Special Play - Castling Short
if (pieceToMove is King && destination.Column == origin.Column + 2)
{
ExecuteCastlingShort(origin, pieceToMove);
}
// Special Play - Castling Long
if (pieceToMove is King && destination.Column == origin.Column - 2)
{
ExecuteCastlingLong(origin, pieceToMove);
}
// Special Play - En Passant
if (pieceToCapture == null && pieceToMove is Pawn && origin.Column != destination.Column)
{
pieceToCapture = ExecuteEnPassant(destination, pieceToMove, pieceToCapture);
}
return(pieceToCapture);
}
private void ExecuteCastlingLong(Position origin, Piece pieceToMove)
{
Position rookOrigin = new Position(origin.Line, origin.Column - 4);
Position rookDestination = new Position(origin.Line, origin.Column - 1);
Piece rook = Board.RemovePieceFromBoard(rookOrigin);
rook.IncrementMovementQuantity();
Board.AddPieceToBoard(rook, rookDestination);
}
public void ExecutePlay(Position origin, Position destination)
{
Piece capturedPiece = ExecuteMovement(origin, destination);
if (IsKingInCheck(CurrentPlayer))
{
UndoMovement(origin, destination, capturedPiece);
throw new BoardException("You cannot place your own King in check. Your play will be undone.");
}
// Get a reference for the piece moved in this turn
Piece pieceMovedInTheTurn = Board.Piece(destination);
// Special Play - Promotion
if (pieceMovedInTheTurn is Pawn)
{
if (pieceMovedInTheTurn.Color == PieceColor.White && destination.Line == 0 || pieceMovedInTheTurn.Color == PieceColor.Black && destination.Line == 7)
{
pieceMovedInTheTurn = Board.RemovePieceFromBoard(destination);
piecesInGame.Remove(pieceMovedInTheTurn);
Piece queen = new Queen(pieceMovedInTheTurn.Color, Board);
Board.AddPieceToBoard(queen, destination);
piecesInGame.Add(queen);
}
}
if (IsKingInCheck(FindAdversaryColor(CurrentPlayer)))
{
IsInCheck = true;
}
else
{
IsInCheck = false;
}
if (IsKingInCheckMate(FindAdversaryColor(CurrentPlayer)))
{
MatchIsFinished = true;
}
else
{
Turn++;
ChangePlayer();
}
// Special Play - En Passant
if (pieceMovedInTheTurn is Pawn && destination.Line == origin.Line - 2 || destination.Line == origin.Line + 2)
{
VulnerableToEnPassant = pieceMovedInTheTurn;
}
else
{
VulnerableToEnPassant = null;
}
}
private void UndoCastlingLong(Piece pieceToGoBack, Position origin, Position destination)
{
if (pieceToGoBack is King && destination.Column == origin.Column - 2)
{
Position rookOrigin = new Position(origin.Line, origin.Column - 4);
Position rookDestination = new Position(origin.Line, origin.Column - 1);
Piece rook = Board.RemovePieceFromBoard(rookDestination);
rook.DecrementMovementQuantity();
Board.AddPieceToBoard(rook, rookOrigin);
}
}
private void UndoMovement(Position origin, Position destination, Piece capturedPiece)
{
Piece pieceToGoBack = Board.RemovePieceFromBoard(destination);
pieceToGoBack.DecrementMovementQuantity();
if (capturedPiece != null)
{
Board.AddPieceToBoard(capturedPiece, destination);
piecesCaptured.Remove(capturedPiece);
}
Board.AddPieceToBoard(pieceToGoBack, origin);
// Special Play - Castling Short
UndoCastlingShort(pieceToGoBack, origin, destination);
// Special Play - Castling Long
UndoCastlingLong(pieceToGoBack, origin, destination);
// Special Play - En Passant
UndoEnPassant(pieceToGoBack, capturedPiece, origin, destination);
}
private void UndoEnPassant(Piece pieceToGoBack, Piece capturedPiece, Position origin, Position destination)
{
// The UndoMovement method returns the captured Pawn to the wrong position after a EnPessant play is undone
// The method bellow will take this Pawn and move it from the wrong position to the right position
if (pieceToGoBack is Pawn && origin.Column != destination.Column && capturedPiece == VulnerableToEnPassant)
{
Piece capturedPawn = Board.RemovePieceFromBoard(destination);
Position capturedPawnOrigin;
if (pieceToGoBack.Color == PieceColor.White)
{
capturedPawnOrigin = new Position(3, destination.Column);
}
else
{
capturedPawnOrigin = new Position(4, destination.Column);
}
Board.AddPieceToBoard(capturedPawn, capturedPawnOrigin);
}
}
private void PlaceNewPiece(char column, int line, Piece piece)
{
Board.AddPieceToBoard(piece, new ChessPosition(column, line).ToPosition());
piecesInGame.Add(piece);
}