/** Copyright by Barry G. Becker, 2000-2011. Licensed under MIT License: http://www.opensource.org/licenses/MIT */
package com.barrybecker4.game.twoplayer.go.board;
import com.barrybecker4.game.common.GameContext;
import com.barrybecker4.game.common.Move;
import com.barrybecker4.game.common.MoveList;
import com.barrybecker4.game.common.board.BoardPosition;
import com.barrybecker4.game.common.player.PlayerList;
import com.barrybecker4.game.twoplayer.common.TwoPlayerBoard;
import com.barrybecker4.game.twoplayer.common.TwoPlayerMove;
import com.barrybecker4.game.twoplayer.common.TwoPlayerSearchable;
import com.barrybecker4.game.twoplayer.common.cache.ScoreCache;
import com.barrybecker4.game.twoplayer.go.board.analysis.BoardEvaluator;
import com.barrybecker4.game.twoplayer.go.board.analysis.group.GroupAnalyzer;
import com.barrybecker4.game.twoplayer.go.board.elements.group.IGoGroup;
import com.barrybecker4.game.twoplayer.go.board.move.GoMove;
import com.barrybecker4.game.twoplayer.go.board.move.GoMoveGenerator;
import com.barrybecker4.game.twoplayer.go.board.move.UrgentMoveGenerator;
import com.barrybecker4.game.twoplayer.go.board.update.DeadStoneUpdater;
import com.barrybecker4.optimization.parameter.ParameterArray;
import java.util.List;
/**
* For searching go game's search space.
*
* @author Barry Becker
*/
public class GoSearchable extends TwoPlayerSearchable {
/** keeps track of dead stones. */
private DeadStoneUpdater deadStoneUpdater_;
private BoardEvaluator boardEvaluator_;
/**
* Constructor.
*/
public GoSearchable(TwoPlayerBoard board, PlayerList players, ScoreCache cache) {
super(board, players);
init(cache);
}
public GoSearchable(GoSearchable searchable) {
super(searchable);
init(searchable.getScoreCache());
}
@Override
public GoSearchable copy() {
return new GoSearchable(this);
}
@Override
public GoBoard getBoard() {
return (GoBoard) board_;
}
public ScoreCache getScoreCache() {
return boardEvaluator_.getCache();
}
/** don't really want to expose this, but renderer needs it */
public GroupAnalyzer getGroupAnalyzer(IGoGroup group) {
return boardEvaluator_.getGroupAnalyzer(group);
}
private void init(ScoreCache cache) {
deadStoneUpdater_ = new DeadStoneUpdater(getBoard());
boardEvaluator_ = new BoardEvaluator(getBoard(), cache);
}
@Override
protected GoProfiler getProfiler() {
return GoProfiler.getInstance();
}
/**
* Given a move determine whether the game is over.
* If recordWin is true then the variables for player1/2HasWon can get set.
* Sometimes, like when we are looking ahead, we do not want to set these.
* The game is over if we have a resignation move, or the last two moves were passing moves.
*
* @param move the move to check
* @param recordWin if true then the controller state will record wins
* @return true if the game is over
*/
@Override
public final boolean done( TwoPlayerMove move, boolean recordWin ) {
boolean gameOver = false;
if (move == null ) {
gameOver = true;
}
else if (move.isResignationMove()) {
if (recordWin) {
setWinner(!move.isPlayer1());
}
gameOver = true;
}
else if (twoPasses(move)) {
if (recordWin) {
setWinner(getFinalScore(true) > getFinalScore(false));
}
gameOver = true;
}
if (!gameOver) {
// try normal handling
gameOver = super.done(move, recordWin );
}
if (gameOver && recordWin) {
doFinalBookKeeping();
}
return gameOver;
}
/**
* Update final territory and number of dead stones.
* Include this in calcWorth because we call updateTerritory which is under calcWorth for timing.
*/
private void doFinalBookKeeping() {
getProfiler().startCalcWorth();
boardEvaluator_.updateTerritoryAtEndOfGame();
//we should not call this twice
if (getNumDeadStonesOnBoard(true) > 0 || getNumDeadStonesOnBoard(false) > 0) {
GameContext.log(0, " Error: should not update life and death twice.");
}
// now that we are finally at the end of the game,
// update the life and death of all the stones still on the board
GameContext.log(1, "about to update life and death." );
deadStoneUpdater_.determineDeadStones();
getProfiler().stopCalcWorth();
}
/**
* Statically evaluate the board position.
* @return statically evaluated value for the board.
* a positive value means that player1 has the advantage.
* A big negative value means a good move for p2.
*/
@Override
public int worth( TwoPlayerMove lastMove, ParameterArray weights ) {
return boardEvaluator_.worth(lastMove, weights, getHashKey());
}
/**
* get the number of black (player1=true) or white (player1=false) stones that were captured and removed.
* @param player1sStones if true, get the captures for player1, else for player2.
* @return num captures of the specified color
*/
public int getNumCaptures( boolean player1sStones ) {
return getBoard().getNumCaptures(player1sStones);
}
/**
* @param move the move to play.
*/
@Override
public void makeInternalMove( TwoPlayerMove move) {
super.makeInternalMove(move);
updateHashIfCaptures((GoMove) move);
}
/**
* takes back the most recent move.
* @param move move to undo
*/
@Override
public void undoInternalMove( TwoPlayerMove move) {
super.undoInternalMove(move);
updateHashIfCaptures((GoMove) move);
}
/**
* Whether we are removing captures from the board or adding them back, the operation is the same: XOR.
*/
private void updateHashIfCaptures(GoMove goMove) {
if (goMove.getNumCaptures() > 0) {
for (BoardPosition pos : goMove.getCaptures()) {
hash.applyMove(pos.getLocation(), getBoard().getStateIndex(pos));
}
// this is needed to disambiguate ko's and positions that have captures.
if (goMove.isKo(getBoard()) || goMove.getNumCaptures() > 0) {
hash.applyMoveNumber(getNumMoves() + goMove.getNumCaptures());
}
}
}
/**
* @param move last move
* @return true if last two moves were passing moves.
*/
private boolean twoPasses(TwoPlayerMove move) {
List moves = moveList_;
if ( move.isPassingMove() && moves.size() > 2 ) {
GoMove secondToLast = (GoMove) moves.get( moves.size() - 2 );
if ( secondToLast.isPassingMove() ) {
GameContext.log( 0, "Done: The last 2 moves were passes :" + move + ", " + secondToLast );
return true;
}
}
return false;
}
/**
* @param player1 if true, set player1 as the winner, else player2.
*/
private void setWinner(boolean player1) {
if (player1) {
players_.getPlayer1().setWon(true);
}
else {
players_.getPlayer2().setWon(true);
}
}
/**
* get a territory estimate for player1 or player2
* When the game is over, this should return a precise value for the amount of territory
* (not yet filled with captures).
* So the estimate will be very rough at the beginning of the game, but should get better as more pieces are played.
*
* Since this can be called while we are processing, we return cached values in
* those cases to avoid a ConcurrentModificationException.
*
* @param forPlayer1 if true, get the captures for player1, else for player2
* @return estimate of the amount of territory the player has
*/
public int getTerritoryEstimate( boolean forPlayer1 ) {
Move m = moveList_.getLastMove();
if ( m == null )
return 0;
return boardEvaluator_.getTerritoryEstimate(forPlayer1, false);
}
/**
* Call this at the end of the game when we need to try to get an accurate score.
* @param forPlayer1 true if player one (black)
* @return the actual score (each empty space counts as one)
*/
public int getFinalTerritory(boolean forPlayer1) {
return boardEvaluator_.getTerritoryEstimate(forPlayer1, true);
}
/**
* Only valid after final bookkeeping has been done at the end of the game.
* @param forPlayer1 player to get dead stones for.
* @return number of dead stones of specified players color.
*/
public int getNumDeadStonesOnBoard(boolean forPlayer1) {
return deadStoneUpdater_.getNumDeadStonesOnBoard(forPlayer1);
}
/**
* @param player1 if true, then the score for player one is returned else player2's score is returned
* @return the score (larger is better regardless of player)
*/
public double getFinalScore(boolean player1) {
int numDead = getNumDeadStonesOnBoard(player1);
int totalCaptures = numDead + getNumCaptures(!player1);
int p1Territory = getFinalTerritory(player1);
String side = (player1? "black":"white");
GameContext.log(1, "----");
GameContext.log(1, "final score for "+ side);
GameContext.log(2, "getNumCaptures(" + side + ")=" + getNumCaptures(player1));
GameContext.log(2, "num dead " + side + " stones on board: "+ numDead);
GameContext.log(2, "getTerritory(" + side + ")="+p1Territory);
GameContext.log(0, "terr + totalEnemyCaptures="+ (p1Territory + totalCaptures));
return p1Territory + totalCaptures;
}
/**
* @return any moves that take captures or get out of atari.
*/
@Override
public final MoveList generateUrgentMoves( TwoPlayerMove lastMove, ParameterArray weights) {
UrgentMoveGenerator generator = new UrgentMoveGenerator(getBoard());
return generator.generateUrgentMoves(generateMoves(lastMove, weights), lastMove);
}
/**
* True if the specified move caused CRITICAL_GROUP_SIZE or more opponent pieces to become jeopardized
* For go, if the specified move caused a sufficiently large group of stones to become in atari, then we return true.
*
* @return true if the last move created a big change in the score
*/
@Override
public boolean inJeopardy( TwoPlayerMove move, ParameterArray weights) {
return UrgentMoveGenerator.inJeopardy((GoMove) move, getBoard());
}
/**
* generate all good next moves (statically evaluated)
*/
@Override
public final MoveList generateMoves(TwoPlayerMove lastMove, ParameterArray weights) {
GoMoveGenerator generator = new GoMoveGenerator(this);
return generator.generateEvaluatedMoves(lastMove, weights);
}
}