public Set<Move> getAllowedMoves() { // If there is already a winn if (gipfBoardState.players.winner() != null) { return Collections.emptySet(); } // Create a set of incomplete moves containing the starting positions and directions for the // current piece Set<Move> potentialMoves = getPotentialStartMoves(getCurrentPiece()); // If the current piece is a GIPF piece, the player is also allowed to place normal pieces. if (getCurrentPiece().getPieceType() == GIPF) potentialMoves.addAll( getPotentialStartMoves(Piece.of(NORMAL, getCurrentPiece().getPieceColor()))); // These moves are marked as complete so a temporary game won't ask for user input. potentialMoves.stream().forEach(m -> m.isCompleteMove = true); Set<Move> potentialMovesIncludingLineSegmentRemoval = new HashSet<>(); for (Move potentialMove : potentialMoves) { try { Map<Position, Piece> temporaryPieceMap = new HashMap<>(getGipfBoardState().getPieceMap()); temporaryPieceMap.put(potentialMove.startPos, potentialMove.addedPiece); movePiecesTowards( temporaryPieceMap, potentialMove.getStartingPosition(), potentialMove.getDirection()); Set<List<Pair<PieceColor, Line.Segment>>> RLineOrderingsSet = getRemovableLineOrderingsSetFromGipfBoard( temporaryPieceMap, getCurrentPiece().getPieceColor()); if (RLineOrderingsSet.size() > 0) { for (List<Pair<PieceColor, Line.Segment>> RLineOrdering : RLineOrderingsSet) { Set<Position> piecesToWhite = new HashSet<>(); Set<Position> piecesToBlack = new HashSet<>(); Set<Position> piecesRemoved = new HashSet<>(); for (Pair<PieceColor, Line.Segment> RLine : RLineOrdering) { Line.Segment removedSegment = RLine.getValue(); // The color of the player who removed the line PieceColor colorRemoved = RLine.getKey(); // Determine per segment to whom the pieces are given. Pieces can only be given to the // player // who removed the line, or deleted from the game. Set<Position> occupiedPositions = removedSegment.getOccupiedPositions(temporaryPieceMap); Set<Position> piecesFromSegmentBackToReserve = occupiedPositions .stream() .filter( position -> temporaryPieceMap.get(position).getPieceColor() == colorRemoved) .collect(toSet()); Set<Position> piecesFromSegmentRemoved = occupiedPositions .stream() .filter(position -> !piecesFromSegmentBackToReserve.contains(position)) .collect(toSet()); if (colorRemoved == WHITE) piecesToWhite.addAll(piecesFromSegmentBackToReserve); if (colorRemoved == BLACK) piecesToBlack.addAll(piecesFromSegmentBackToReserve); piecesRemoved.addAll(piecesFromSegmentRemoved); } // And finally add the move // the constructor will define this as a complete move, because all the parameters have // a value. potentialMovesIncludingLineSegmentRemoval.add( new Move( potentialMove.addedPiece, potentialMove.startPos, potentialMove.direction, piecesToWhite, piecesToBlack, piecesRemoved)); } } else { // If no line segments can be removed, just add the original move potentialMovesIncludingLineSegmentRemoval.add(potentialMove); } } catch (InvalidMoveException e) { // We don't consider this move if it is invalid } } return potentialMovesIncludingLineSegmentRemoval; }