public void returnToPreviousBoard() {
if (boardHistory.size() > 1) {
gipfBoardState = boardHistory.pop();
loadState(gipfBoardState);
gameLogger.log("Returned to previous game state");
}
}
Game() {
/*
* Initialize a new starting GipfBoardState object for this game. The initializePieceMap() and initializePlayers()
* methods are meant to be overridden by the classes extending the game class.
*/
this.gipfBoardState = new GipfBoardState(null, initializePieceMap(), initializePlayers());
boardHistory = new BoardHistory();
boardHistory.add(gipfBoardState);
/*
* Empty logger, for now it makes no sense to store all the log data in all generated games. String concatenations
* are relatively expensive and the output is shown nowhere.
*/
gameLogger = new EmptyLogger();
}
/**
* applyMove applies the given move to the board. First, the new piece is added to the startPos
* Then the pieces are moved in the direction of the move, and finally pieces that need to be
* removed are removed from the board
*
* @param move the move that is applied
*/
public void applyMove(Move move) {
// An invalidMoveException can be thrown if applying that move would mean to place pieces on an
// illegal position.
try {
moveCounter++;
// If there's already a winner, the move won't be applied
if (gipfBoardState.players.winner() != null) return;
/*
* Prepare for creating a new child GipfBoardState. The pieceMap and playersInGame objects of the current
* gipfBoardState are unmodifiable, so we have to create modifiable copies.
* If the move turns out to be legal, a new child GipfBoardState will be generated, based on the modified
* copies of the PieceMap and the PlayersInGame objects.
*/
// The piece map returned by getPieceMap() is unmodifiable, so it has to be converted to a new
// (hash) map
// the newPieceMap can be modified, after that a new GipfBoardState can be generated.
Map<Position, Piece> newPieceMap = new HashMap<>(gipfBoardState.getPieceMap());
// The same is true for the PlayersInGame object. It is unmodifiable, so a new instance has to
// be created
// for the new board state.
PlayersInGame newPlayers = new PlayersInGame(gipfBoardState.players);
// If the current player has enough pieces left in the reserve to perform the move (1 for a
// normal move, 2 for
// a Gipf move.)
if (newPlayers.current().reserve >= move.addedPiece.getPieceValue()) {
/*
* Move the piece
*/
// Each move adds a new piece to the board
newPieceMap.put(move.startPos, move.addedPiece);
// Move it into the direction determined by the move
movePiecesTowards(newPieceMap, move.startPos, move.direction);
/*
* Remove the lines and pieces that can be removed from the board
*/
// Create an object that keeps track of which piece is taken by whom. An EnumMap instead of
// a HashMap is
// used, because all keys correspond with values from the PieceColor enum.
Map<PieceColor, Set<Line.Segment>> linesTakenBy = new EnumMap<>(PieceColor.class);
linesTakenBy.put(WHITE, new HashSet<>());
linesTakenBy.put(BLACK, new HashSet<>());
// Create an object that keeps track of which individual pieces are taken by whom.
// A HashMap is used because it can handle null keys, in contrast with EnumMaps.
Map<PieceColor, Set<Position>> piecesBackTo = new HashMap<>();
piecesBackTo.put(WHITE, new HashSet<>());
piecesBackTo.put(BLACK, new HashSet<>());
piecesBackTo.put(null, new HashSet<>()); // Used for pieces that are removed from the board
/*
* Distinguish between complete and incomplete moves.
* - Complete moves:
* are generated by the getAllowedMoves() method and contain all information about that move,
* including a choice for which lines or gipf pieces will be removed.
* - Incomplete moves:
* are performed by human players. These moves don't contain the information of which pieces are
* removed. This means that there may be user interaction required if the player must choose between
* multiple lines or gipf pieces that can be removed.
*/
if (move.isCompleteMove) {
// Complete moves are the easiest to handle, the positions of pieces that are removed are
// already
// determined.
// This means that we only have to read the values for the pieces that are returned to
// each player
// into the piecesBackTo map.
piecesBackTo.get(WHITE).addAll(move.piecesToWhite);
piecesBackTo.get(BLACK).addAll(move.piecesToBlack);
piecesBackTo.get(null).addAll(move.piecesRemoved);
} else {
// Now we have incomplete moves. This means that we have to remove the pieces that are
// required to
// be removed. If the player must choose between different pieces / lines, the removeLines
// method
// will ask the player to make a choice.
// Get the lines that are taken by the current player (retrieved from linesTakenBy) and
// store them
// in the piecesBackTo map. The opponent's pieces are stored in piecesBackTo.get(null),
// because they
// are removed from the board.
removeLines(newPieceMap, newPlayers.current().pieceColor, linesTakenBy, piecesBackTo);
// linesTakenBy.get(newPlayers.current().pieceColor).addAll(getRemovableLineSegments(newPieceMap, newPlayers.current().pieceColor));
// Get the lines that are taken by the opponent (retrieved from the linesTakenBy map), and
// store
// them in the piecesBackTo map. The current player's pieces are stored in
// piecesBackTO.get(null),
// because they are removed from the board.
PieceColor opponentColor = newPlayers.current().pieceColor == WHITE ? BLACK : WHITE;
removeLines(newPieceMap, opponentColor, linesTakenBy, piecesBackTo);
// linesTakenBy.get(opponentColor).addAll(getRemovableLineSegments(newPieceMap,
// opponentColor));
}
gameLogger.log(move.toString());
// Each value in the piecesBackTo map is a set, and each element (position) of the sets of
// all values
// is removed from the pieceMap.
// The number of the returned pieces for each player are added to their reserve.
for (Map.Entry<PieceColor, Set<Position>> removedPieces : piecesBackTo.entrySet()) {
if (removedPieces.getKey() != null) {
// Calculate the sum for the pieces returned to this player. Normal pieces have a value
// of 1,
// gipf pieces a value of 2 determined in Piece.getPieceValue().
int returnedPiecesSum =
removedPieces
.getValue()
.stream()
.mapToInt(
position -> {
if (newPieceMap.containsKey(position))
return newPieceMap.get(position).getPieceValue();
else return 1;
})
.sum();
newPlayers.get(removedPieces.getKey()).reserve += returnedPiecesSum;
gameLogger.log(removedPieces.getKey() + " retrieved " + returnedPiecesSum + " pieces");
}
// The pieces are not earlier removed from the board, because the returnedPiecesSum
// variable can
// only be set if all the pieces are still on the board.
removePiecesFromPieceMap(newPieceMap, removedPieces.getValue());
}
/*
* Set the properties for the player, based on the move
*/
if (move.addedPiece.getPieceType() == PieceType.GIPF) {
newPlayers.current().hasPlacedGipfPieces = true;
}
if (!newPlayers.current().isPlacingGipfPieces) {
newPlayers.current().hasPlacedNormalPieces = true;
}
// Update the current player's reserve for the last added piece
newPlayers.current().reserve -= move.addedPiece.getPieceValue();
/*
* Check whether it is game over
*/
// If we create a new GipfBoardState based on the calculated properties, will there be a
// game over situation?
if (getGameOverState(new GipfBoardState(null, newPieceMap, newPlayers))) {
// If the current player causes a game over situation, the other player (updateCurrent()),
// will be
// the winner of the game.
newPlayers = newPlayers.updateCurrent().makeCurrentPlayerWinner();
gameLogger.log("Game over! " + newPlayers.winner().pieceColor + " won!");
if (moveCounter != 1) {
if (SettingsSingleton.getInstance().showExperimentOutput) {
String moveCountString = Integer.toString(moveCounter);
String durationString =
Long.toString(Duration.between(gameStartInstant, Instant.now()).toMillis());
String winnerString = newPlayers.winner().pieceColor.toString();
String whiteAlgorithm = whitePlayer.getClass().getSimpleName();
String blackAlgorithm = blackPlayer.getClass().getSimpleName();
ExperimentLogger.get()
.log(
whiteAlgorithm
+ "; "
+ blackAlgorithm
+ "; "
+ moveCountString
+ "; "
+ durationString
+ "; "
+ winnerString);
}
}
}
// We don't need to update the current player if the game has ended
if (newPlayers.winner() == null) {
newPlayers = newPlayers.updateCurrent();
}
// Create a new gipfBoardState, based on the calculated PieceMap and PlayersInGame objects.
GipfBoardState newGipfBoardState =
new GipfBoardState(gipfBoardState, newPieceMap, newPlayers);
boardHistory.add(gipfBoardState);
this.gipfBoardState = newGipfBoardState;
} else {
gameLogger.log("No pieces left");
}
// Recalculate the properties of this gipfBoardState
gipfBoardState.boardStateProperties.updateBoardState();
} catch (InvalidMoveException e) {
System.out.println("Move not applied");
}
}