protected override bool IsValidRule(
PieceBase piece,
Position newPosition,
Chessboard chessboard)
{
var(filesToMove, ranksToMove) = piece.GetDistanceTo(newPosition);
if (filesToMove > 1)
{
return(false);
}
if (ranksToMove == 0)
{
return(false);
}
if (ranksToMove > 2)
{
return(false);
}
if (ranksToMove == 2 && !piece.IsFirstMove)
{
return(false);
}
if (chessboard.GetPiece(newPosition) && filesToMove != ranksToMove)
{
return(false);
}
if (filesToMove == ranksToMove && !chessboard.GetPiece(newPosition))
{
return(false);
}
var(horizontal, _) = piece.GetDirectionTo(newPosition);
if (piece.Color == WhitePiece && horizontal.Equals(Bottom))
{
return(false);
}
if (piece.Color == BlackPiece && horizontal.Equals(Top))
{
return(false);
}
return(true);
}