internal override List <PiecePosition> GetPossiblePiecePositions(PiecePosition position, Board board)
{
var positions = GetPossiblePiecePositionsWithoutRoque(position, board);
if (CanBigRoque(board))
{
positions.Add(new PiecePosition('A', _initialeLine));
}
if (CanSmallRoque(board))
{
positions.Add(new PiecePosition('H', _initialeLine));
}
return(positions);
}
internal List <PiecePosition> GetPossiblePiecePositionsWithoutRoque(PiecePosition position, Board board)
{
return(new List <PiecePosition>
{
new PiecePosition((char)(position.Column - 1), position.Line - 1),
new PiecePosition((char)(position.Column - 1), position.Line),
new PiecePosition((char)(position.Column - 1), position.Line + 1),
new PiecePosition(position.Column, position.Line + 1),
new PiecePosition(position.Column, position.Line - 1),
new PiecePosition((char)(position.Column + 1), position.Line - 1),
new PiecePosition((char)(position.Column + 1), position.Line),
new PiecePosition((char)(position.Column + 1), position.Line + 1)
}
.Where(x => IsInBoard(x) && !IsOccupiedBySameColorPiece(board, x) && !board.IsPositionThreatened(x, Color))
.ToList());
}
private bool Roque(PiecePosition fromPosition, PiecePosition toPosition)
{
var pieceToMove = GetPiece(fromPosition) as King;
var pieceAtDestination = GetPiece(toPosition) as Rook;
if (pieceToMove == null || pieceAtDestination == null)
{
return(false);
}
var king = GetPiece(fromPosition);
var rook = GetPiece(toPosition);
SetPiece(toPosition, king);
SetPiece(fromPosition, rook);
return(true);
}
private bool CanBigRoque(Board board)
{
if (HasMoved)
{
return(false);
}
var rook = board.GetPiece(new PiecePosition('A', _initialeLine));
if (rook.HasMoved)
{
return(false);
}
for (char col = 'B'; col <= 'D'; col++)
{
var piecePosition = new PiecePosition(col, _initialeLine);
if (board.GetPiece(piecePosition) != null || board.IsPositionThreatened(piecePosition, Color))
{
return(false);
}
}
return(true);
}
public bool IsPositionThreatened(PiecePosition position, PieceColor color)
{
PieceColor colorThreat;
if (color == PieceColor.Black)
{
colorThreat = PieceColor.White;
}
else if (color == PieceColor.White)
{
colorThreat = PieceColor.Black;
}
else
{
throw new ArgumentException("Unknown piece color");
}
var allPositionsThreatened = new List <PiecePosition>();
for (char col = 'A'; col <= 'H'; col++)
{
for (int line = 1; line <= 8; line++)
{
var piecePosition = new PiecePosition(col, line);
var piece = GetPiece(piecePosition);
if (piece?.Color == colorThreat)
{
var possiblePiecePositions = GetPossiblePiecePositions(piecePosition);
if (possiblePiecePositions != null)
{
allPositionsThreatened.AddRange(possiblePiecePositions);
}
}
}
}
return(allPositionsThreatened.Contains(position));
}
internal override List <PiecePosition> GetPossiblePiecePositions(PiecePosition position, Board board)
{
return(GetDiagonalMoves(position, board));
}
internal override List <PiecePosition> GetPossiblePiecePositions(PiecePosition position, Board board)
{
return(GetForwardBackwardMoves(position, board));
}
internal abstract List <PiecePosition> GetPossiblePiecePositions(PiecePosition position, Board board);
protected List <PiecePosition> GetForwardBackwardMoves(PiecePosition position, Board board)
{
var positions = new List <PiecePosition>();
int line = position.Line + 1;
while (IsInBoard(position.Column, line))
{
var newPosition = new PiecePosition(position.Column, line);
if (IsOccupiedBySameColorPiece(board, newPosition))
{
break;
}
positions.Add(newPosition);
if (IsOccupiedByOtherColorPiece(board, newPosition))
{
break;
}
line++;
}
line = position.Line - 1;
while (IsInBoard(position.Column, line))
{
var newPosition = new PiecePosition(position.Column, line);
if (IsOccupiedBySameColorPiece(board, newPosition))
{
break;
}
positions.Add(newPosition);
if (IsOccupiedByOtherColorPiece(board, newPosition))
{
break;
}
line--;
}
char column = (char)(position.Column + 1);
while (IsInBoard(column, position.Line))
{
var newPosition = new PiecePosition(column, position.Line);
if (IsOccupiedBySameColorPiece(board, newPosition))
{
break;
}
positions.Add(newPosition);
if (IsOccupiedByOtherColorPiece(board, newPosition))
{
break;
}
column++;
}
column = (char)(position.Column - 1);
while (IsInBoard(column, position.Line))
{
var newPosition = new PiecePosition(column, position.Line);
if (IsOccupiedBySameColorPiece(board, newPosition))
{
break;
}
positions.Add(newPosition);
if (IsOccupiedByOtherColorPiece(board, newPosition))
{
break;
}
column--;
}
return(positions);
}
protected bool IsOccupiedByOtherColorPiece(Board board, PiecePosition position)
{
var newPiece = board.GetPiece(position);
return(newPiece != null && newPiece?.Color != Color);
}
protected bool IsOccupiedBySameColorPiece(Board board, PiecePosition position)
{
var newPiece = board.GetPiece(position);
return(newPiece?.Color == Color);
}
protected bool IsInBoard(PiecePosition position)
{
return(IsInBoard(position.Column, position.Line));
}
private void SetPiece(PiecePosition position, Piece piece)
{
_pieces[position.Column - 'A', position.Line - 1] = piece;
}
public List <PiecePosition> GetPossiblePiecePositions(PiecePosition position)
{
var piece = GetPiece(position);
return(piece?.GetPossiblePiecePositions(position, this));
}
private void RemovePiece(PiecePosition position)
{
_pieces[position.Column - 'A', position.Line - 1] = null;
}