/// <summary>
/// Checks if a player is mated (no legal moves)
/// </summary>
/// <param name="color">Color of player to check</param>
/// <param name="positionIsStaleMate">Set to true on stalemate</param>
/// <returns>True if there are no legal moves for the player color</returns>
private bool PlayerMated(PieceColor color, out bool positionIsStaleMate)
{
positionIsStaleMate = false;
bool result = true;
List <ChessPiece> pieces = (color == PieceColor.White) ? board.WhitePieces : board.BlackPieces;
foreach (ChessPiece piece in pieces)
{
if (!piece.Captured && LegalChessMovesGenerator.GetLegalMoves(piece, board).Count() > 0)
{
result = false;
break;
}
}
if (result)
{
// Verify the King is in check, if not, stalemate
ChessPiece king = board.GetKing(color);
if (!LegalChessMovesGenerator.IsSquareInCheck(board, king.File, king.Rank, color))
{
positionIsStaleMate = true;
}
}
return(result);
}
/// <summary>
/// Should only be called after a game over event, no draws right now in normal
/// play so find the mated player, or possibly the stalemate.
/// </summary>
/// <returns>GameResult value</returns>
public GameResult GetWinner()
{
bool whiteStalemate = false;
bool whiteMated = PlayerMated(PieceColor.White, out whiteStalemate);
bool blackStalemate = false;
bool blackMated = PlayerMated(PieceColor.Black, out blackStalemate);
bool activeMated = (ActivePlayer == PieceColor.White) ? whiteMated : blackMated;
bool opponentMated = (ActivePlayer == PieceColor.White) ? blackMated : whiteMated;
bool activeStalemate = (ActivePlayer == PieceColor.White) ? whiteStalemate : blackStalemate;
ChessPiece playerKing = board.GetKing(PieceColor.White);
if (LegalChessMovesGenerator.IsSquareInCheck(board, playerKing.File, playerKing.Rank, playerKing.Color))
{
++checkWhite;
}
playerKing = board.GetKing(PieceColor.Black);
if (LegalChessMovesGenerator.IsSquareInCheck(board, playerKing.File, playerKing.Rank, playerKing.Color))
{
++checkBlack;
}
if (checkWhite == 3 && typeofGame == TypeGame.ThreeCheck)
{
return(GameResult.BlackWins);
}
if (checkBlack == 3 && typeofGame == TypeGame.ThreeCheck)
{
return(GameResult.WhiteWins);
}
//Drawn - neither player has legal moves and neither is in check
if (!opponentMated && activeMated && activeStalemate)
{
return(GameResult.Draw);
}
// Stalemate is stalemate at this point
if (whiteStalemate)
{
return(GameResult.Stalemate);
}
// Still going....needed to check agains engines that behave questionably
// in drawn and or mated positions
if (!opponentMated && !activeMated)
{
return(GameResult.Contested);
}
// we must have an actual winner
return(whiteMated ? GameResult.BlackWins : GameResult.WhiteWins);
}
/// <summary>
/// Process the input when waiting for the current player to select a piece
/// </summary>
/// <param name="x">x coordinate in form</param>
/// <param name="y">y coordinate in form</param>
private void OnWaitingForPieceSelection(int x, int y)
{
ChessPiece foundPiece = ((IChessBoardView)view).GetPiece(x, y);
if ((foundPiece != null) && (foundPiece.Color == PlayerColor))
{
if (foundPiece.Color == PlayerColor)
{
legalMoves = LegalChessMovesGenerator.GetLegalMoves(foundPiece, board);
((IChessBoardView)view).HighlightSquares(ref legalMoves);
((IChessBoardView)view).HighlightSquare(foundPiece.File, foundPiece.Rank);
selectedPiece = foundPiece;
}
}
}
