/// <summary>
/// Initializes new Piece by given color and type as:<br/>
/// "wp" => White Pawn<br/>
/// "br" => Black Rook<br/>
/// See: piece.ToString()<br/>
/// </summary>
public Piece(string piece)
{
if (!Regexes.regexPiece.IsMatch(piece))
{
throw new ChessArgumentException(null, "Piece should match pattern: " + Regexes.PiecePattern);
}
Color = PieceColor.FromChar(piece[0]);
Type = PieceType.FromChar(piece[1]);
}
/// <summary>
/// Initializes new Piece by given color and type as FEN:<br/>
/// 'Q' => White Queen<br/>
/// 'q' => Black Queen<br/>
/// See: piece.ToFENChar()<br/>
/// </summary>
public Piece(char fenChar)
{
if (!Regexes.regexFenPiece.IsMatch(fenChar.ToString()))
{
throw new ChessArgumentException(null, "FEN piece character should match pattern: " + Regexes.FenPiecePattern);
}
Type = PieceType.FromChar(fenChar);
Color = char.IsLower(fenChar) ? PieceColor.Black : PieceColor.White;
}
public static (bool succeeded, ChessException?exception) TryParse(ChessBoard board, string san, out Move?move, bool resetSan = false)
{
move = null;
var matches = Regexes.regexSanOneMove.Matches(san);
if (matches.Count == 0)
{
return(false, new ChessArgumentException(board, "SAN move string should match pattern: " + Regexes.SanMovesPattern));
}
Move moveOut = new();
Position originalPos = new();
bool isCapture = false;
foreach (var group in matches[0].Groups.Values)
{
if (!group.Success)
{
continue;
}
switch (group.Name)
{
case "1":
if (group.Value == "O-O" || group.Value == "O-O-O")
{
moveOut.Parameter = IMoveParameter.FromString(group.Value);
if (board.Turn == PieceColor.White)
{
originalPos = new("e1");
if (group.Value == "O-O")
{
moveOut.NewPosition = new("h1");
}
else if (group.Value == "O-O-O")
{
moveOut.NewPosition = new("a1");
}
}
else if (board.Turn == PieceColor.Black)
{
originalPos = new("e8");
if (group.Value == "O-O")
{
moveOut.NewPosition = new("h8");
}
else if (group.Value == "O-O-O")
{
moveOut.NewPosition = new("a8");
}
}
// not realy needed
//if (!IsValidMove(new Move(originalPos, moveOut.NewPosition)))
// throw new ChessSanNotFoundException(this, move);
}
break;
case "2":
moveOut.Piece = new Piece(board.Turn, PieceType.FromChar(group.Value[0]));
break;
case "3":
originalPos.X = Position.FromFile(group.Value[0]);
break;
case "4":
originalPos.Y = Position.FromRank(group.Value[0]);
break;
case "5":
if (group.Value == "x" || group.Value == "X")
{
isCapture = true;
}
break;
case "6":
moveOut.NewPosition = new Position(group.Value);
break;
case "7":
moveOut.Parameter = IMoveParameter.FromString(group.Value.Trim());
break;
case "9":
switch (group.Value)
{
case "+":
moveOut.IsCheck = true;
break;
case "#":
moveOut.IsCheck = true;
moveOut.IsMate = true;
break;
case "$":
moveOut.IsMate = true;
break;
}
break;
}
}
// If piece is not specified => Pawn
moveOut.Piece ??= new Piece(board.Turn, PieceType.Pawn);
if (isCapture && board[moveOut.NewPosition] is not null)
{
moveOut.CapturedPiece = board[moveOut.NewPosition];
}
if (!originalPos.HasValue)
{
var amb = GetMovesOfPieceOnPosition(moveOut.Piece, moveOut.NewPosition, board).ToList();
if (originalPos.HasValueX)
{
amb = amb.Where(m => m.OriginalPosition.X == originalPos.X).ToList();
if (amb.Count != 1)
{
return(false, ThrowException(amb.Count, amb));
}
originalPos.Y = amb.ElementAt(0).OriginalPosition.Y;
}
else if (originalPos.HasValueY)
{
amb = amb.Where(m => m.OriginalPosition.Y == originalPos.Y).ToList();
if (amb.Count != 1)
{
return(false, ThrowException(amb.Count, amb));
}
originalPos.X = amb.ElementAt(0).OriginalPosition.X;
}
else
{
if (amb.Count != 1)
{
return(false, ThrowException(amb.Count, amb));
}
originalPos.X = amb.ElementAt(0).OriginalPosition.X;
originalPos.Y = amb.ElementAt(0).OriginalPosition.Y;
}
ChessException?ThrowException(int count, List <Move> moves)
{
if (count < 1)
{
return(new ChessSanNotFoundException(board, san));
}
else if (count > 1)
{
return(new ChessSanTooAmbiguousException(board, san, moves.ToArray()));
}
return(null);
}
}
moveOut.OriginalPosition = originalPos;
if (resetSan)
{
TryParse(board, moveOut, out var _);
}
move = moveOut;
return(true, null);
}