public override ReadOnlyCollection<Move> GetValidMoves(Position from, bool returnIfAny, ChessGame game, Func<Move, bool> gameMoveValidator)
{
ChessUtilities.ThrowIfNull(from, "from");
List<Move> validMoves = new List<Move>();
Piece piece = game.GetPieceAt(from);
int l0 = game.BoardHeight;
int l1 = game.BoardWidth;
int[][] directions;
if (piece.Owner == Player.White)
{
directions = new int[][] { new int[] { 0, 1 }, new int[] { 0, 2 }, new int[] { 1, 1 }, new int[] { -1, 1 } };
}
else
{
directions = new int[][] { new int[] { 0, -1 }, new int[] { 0, -2 }, new int[] { -1, -1 }, new int[] { 1, -1 } };
}
foreach (int[] dir in directions)
{
if ((int)from.File + dir[0] < 0 || (int)from.File + dir[0] >= l1
|| from.Rank + dir[1] < 1 || from.Rank + dir[1] > l0)
continue;
Move move = new Move(from, new Position(from.File + dir[0], from.Rank + dir[1]), piece.Owner);
List<Move> moves = new List<Move>();
if ((move.NewPosition.Rank == 8 && move.Player == Player.White) || (move.NewPosition.Rank == 1 && move.Player == Player.Black))
{
foreach (char pieceChar in ValidPromotionPieces.Where(x => char.IsUpper(x)))
{
moves.Add(new Move(move.OriginalPosition, move.NewPosition, move.Player, pieceChar));
}
}
else
{
moves.Add(move);
}
foreach (Move m in moves)
{
if (gameMoveValidator(m))
{
validMoves.Add(m);
if (returnIfAny)
return new ReadOnlyCollection<Move>(validMoves);
}
}
}
return new ReadOnlyCollection<Move>(validMoves);
}
}
