getValidMoves method

Implementation

List<Position> getValidMoves(Position from) {
  ChessPiece? piece = getPiece(from);
  if (piece == null || piece.color != turn) return [];

  List<Position> validMoves = [];

  // Existing valid move logic: iterate over board squares and check if a move is valid.
  for (int row = 0; row < 8; row++) {
    for (int col = 0; col < 8; col++) {
      Position target = Position(row: row, col: col);
      if (MoveValidator.isValidMove(this, from, target)) {
        // (Optional: simulate the move to ensure the king does not end up in check.)
        validMoves.add(target);
      }
    }
  }

  // If the selected piece is the king, add castling moves.
  if (piece.type == PieceType.king) {
    // King‑side castling: king should move to column 6.
    if (MoveValidator.canCastleKingSide(this, piece.color)) {
      validMoves.add(Position(row: from.row, col: 6));
    }
    // Queen‑side castling: king should move to column 2.
    if (MoveValidator.canCastleQueenSide(this, piece.color)) {
      validMoves.add(Position(row: from.row, col: 2));
    }
  }

  return validMoves;
}