public static IEnumerable <Move> GetLegalMoves(Color color, Board board)
{
foreach (int index in Board.Indexes)
{
Piece piece = board[index];
if (!piece.IsPiece())
{
continue;
}
if (piece.ToColor() != color)
{
continue;
}
IEnumerable <int> movableRange = GetMovableRange(index, color, board);
foreach (int candidate in Move.GetMovableIndexes(piece, index))
{
if (piece.ToPieceType() == Piece.Knight)
{
Piece dest = board[candidate];
if (dest != Piece.Empty && dest.ToColor() == color)
{
continue;
}
}
else if (!movableRange.Contains(candidate))
{
continue;
}
yield return(new Move()
{
SrcIndex = index,
DstIndex = candidate,
PieceType = piece.ToPieceType(),
Promote = false
});
if ((color == Color.Black && Board.GetRank(candidate) <= 3) ||
(color == Color.White && Board.GetRank(candidate) >= 7))
{
yield return(new Move()
{
SrcIndex = index,
DstIndex = candidate,
PieceType = piece.ToPieceType(),
Promote = true
});
}
}
}
}
private static bool CheckWhiteKnightDrop(int index)
{
return(Board.GetRank(index) < 8);
}
private static bool CheckBlackKnightDrop(int index)
{
return(Board.GetRank(index) > 2);
}
private static bool CheckWhitePawnLanceDrop(int index)
{
return(Board.GetRank(index) < 9);
}
private static bool CheckBlackPawnLanceDrop(int index)
{
return(Board.GetRank(index) > 1);
}