// create a board with a FEN string
public Board(string fen)
{
Match Match = FenParser.Match(fen);
if (!Match.Success)
{
throw new ArgumentException(string.Format("invalid FEN string \"{0}\"", fen));
}
// piece placement
string Field = Match.Groups[1].Value;
string[] RankPlacement = Field.Split('/');
BoardAddress Location;
int File;
Pieces = new PiecePositions();
for (int rank = 0; rank < 8; rank++)
{
File = 0;
foreach (char c in RankPlacement[7 - rank])
{
Location = new BoardAddress((char)('a' + File), rank);
switch (c)
{
case 'p':
Pieces.Black.Pawns |= Location.Position;
break;
case 'P':
Pieces.White.Pawns |= Location.Position;
break;
case 'n':
Pieces.Black.Knights |= Location.Position;
break;
case 'N':
Pieces.White.Knights |= Location.Position;
break;
case 'b':
Pieces.Black.Bishops |= Location.Position;
break;
case 'B':
Pieces.White.Bishops |= Location.Position;
break;
case 'r':
Pieces.Black.Rooks |= Location.Position;
break;
case 'R':
Pieces.White.Rooks |= Location.Position;
break;
case 'q':
Pieces.Black.Queens |= Location.Position;
break;
case 'Q':
Pieces.White.Queens |= Location.Position;
break;
case 'k':
Pieces.Black.King |= Location.Position;
break;
case 'K':
Pieces.White.King |= Location.Position;
break;
default: // num empty spaces
if (!char.IsDigit(c))
{
throw new ArgumentException(string.Format("invalid character \"{0}\" in piece placement field", c));
}
File += c - '1'; // convert char to int
break;
}
File++;
}
}
// active color
Field = Match.Groups[2].Value.ToLower();
if (Field == "w")
{
ActiveColorWhite = true;
}
else
{
ActiveColorWhite = false;
}
// castling availablity
CastlingAvailability = new Castling();
Field = Match.Groups[3].Value;
if (Field == "-") // not available
{
CastlingAvailability.White = Castling.Move.Disallowed;
CastlingAvailability.Black = Castling.Move.Disallowed;
}
else // available to at least one player
// check white
{
if (Field.Contains("K") && Field.Contains("Q"))
{
CastlingAvailability.White = Castling.Move.BothSides;
}
else if (Field.Contains("K"))
{
CastlingAvailability.White = Castling.Move.KingSide;
}
else if (Field.Contains("Q"))
{
CastlingAvailability.White = Castling.Move.QueenSide;
}
else
{
CastlingAvailability.White = Castling.Move.Disallowed;
}
// check black
if (Field.Contains("k") && Field.Contains("q"))
{
CastlingAvailability.Black = Castling.Move.BothSides;
}
else if (Field.Contains("k"))
{
CastlingAvailability.Black = Castling.Move.KingSide;
}
else if (Field.Contains("q"))
{
CastlingAvailability.Black = Castling.Move.QueenSide;
}
else
{
CastlingAvailability.Black = Castling.Move.Disallowed;
}
}
// enpassant location
Field = Match.Groups[4].Value;
if (Field == "-")
{
EnPassantTarget = 0;
}
else
{
EnPassantTarget = new BoardAddress(Field).Position;
}
// halfmove clock
Field = Match.Groups[5].Value;
if (!byte.TryParse(Field, out HalfMoveClock))
{
throw new ArgumentException(string.Format("could not parse halfmove clock \"{0}\"", Field));
}
// halfmove clock
Field = Match.Groups[6].Value;
if (!int.TryParse(Field, out FullMoveNumber))
{
throw new ArgumentException(string.Format("could not parse full move number \"{0}\"", Field));
}
}
