private static bool IsCheckedRoseDirections(Board board, King king)
{
List <Square> surroundingSquares = new List <Square>();
List <Square> pawnAttackingSquares = new List <Square>();
GenerateSquareLists(surroundingSquares, pawnAttackingSquares, king);
foreach (int fileOffset in new[] { -1, 0, 1 })
{
foreach (int rankOffset in new[] { -1, 0, 1 })
{
if (fileOffset == 0 && rankOffset == 0)
{
continue;
}
Square testSquare = new Square(king.Position, fileOffset, rankOffset);
while (testSquare.IsValid && !board.IsOccupiedBySide(testSquare, king.Color))
{
if (board.IsOccupiedBySide(testSquare, king.Color.Complement()))
{
Piece piece = board[testSquare];
//diagonal direction
if (Math.Abs(fileOffset) == Math.Abs(rankOffset))
{
if (piece is Bishop || piece is Queen || testSquare.Rank == king.Position.Rank + (king.Color == Side.White ? 1 : -1) &&
(testSquare.File == king.Position.File + 1 || testSquare.File == king.Position.File - 1) &&
piece is Pawn)
{
return(true);
}
switch (piece)
{
case King _ when surroundingSquares.Contains(piece.Position):
case Pawn _ when pawnAttackingSquares.Contains(piece.Position):
return(true);
}
}
//cardinal directions
else
{
switch (piece)
{
case Rook _:
case Queen _:
case King _ when surroundingSquares.Contains(piece.Position):
return(true);
}
}
break;
}
testSquare = new Square(testSquare, fileOffset, rankOffset);
}
}
}
return(false);
}
private static void GenerateSquareLists(List <Square> surroundingSquares, List <Square> pawnAttackingSquares, King king)
{
foreach (int fileOffset in new[] { -1, 0, 1 })
{
foreach (int rankOffset in new[] { -1, 0, 1 })
{
if (fileOffset == 0 && rankOffset == 0)
{
continue;
}
Square testSquare = new Square(king.Position, fileOffset, rankOffset);
if (testSquare.IsValid)
{
if ((fileOffset == 1 || fileOffset == -1) && rankOffset == (king.Color == Side.White ? 1 : -1))
{
pawnAttackingSquares.Add(testSquare);
}
surroundingSquares.Add(testSquare);
}
}
}
}
private static bool IsKingInCheck(Board board, King king) => IsCheckedRoseDirections(board, king) || IsCheckedKnightDirections(board, king);
public King(King kingCopy) : base(kingCopy)
{
}
