/** Copyright by Barry G. Becker, 2000-2011. Licensed under MIT License: http://www.opensource.org/licenses/MIT */
package com.barrybecker4.game.twoplayer.go.board.elements.eye;
import com.barrybecker4.game.common.GameContext;
import com.barrybecker4.game.twoplayer.go.board.GoBoard;
import com.barrybecker4.game.twoplayer.go.board.analysis.eye.EyeTypeAnalyzer;
import com.barrybecker4.game.twoplayer.go.board.analysis.eye.information.EyeInformation;
import com.barrybecker4.game.twoplayer.go.board.analysis.eye.information.EyeStatus;
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.elements.position.GoBoardPosition;
import com.barrybecker4.game.twoplayer.go.board.elements.position.GoBoardPositionList;
import com.barrybecker4.game.twoplayer.go.board.elements.position.GoBoardPositionSet;
import com.barrybecker4.game.twoplayer.go.board.elements.position.GoStone;
import com.barrybecker4.game.twoplayer.go.board.elements.string.GoString;
/**
* A GoEye is composed of a strongly connected set of empty spaces (and possibly some dead enemy stones).
* By strongly connected I mean nobi connections only.
* A GoEye may be one of several different eye types enumerated below
* A group needs 2 provably true eyes to live.
*
* @author Barry Becker
*/
public class GoEye extends GoString implements IGoEye {
/** A set of positions that are in the eye space. Need not be empty. */
private GoBoardPositionSet members_;
/** The kind of eye that this is. */
private final EyeInformation information_;
/** In addition to the type, an eye can have a status like nakade, unsettled, or aliveInAtari. */
private final EyeStatus status_;
private int numCornerPoints_;
private int numEdgePoints_;
/**
* Constructor.
* Immutable after construction.
* Create a new eye shape containing the specified list of stones/spaces.
* Some of the spaces may be occupied by dead opponent stones.
*/
public GoEye( GoBoardPositionList spaces, GoBoard board, IGoGroup g, GroupAnalyzer groupAnalyzer) {
super( spaces, board );
group_ = g;
ownedByPlayer1_ = g.isOwnedByPlayer1();
EyeTypeAnalyzer eyeAnalyzer = new EyeTypeAnalyzer(this, board, groupAnalyzer);
information_ = eyeAnalyzer.determineEyeInformation();
status_ = information_.determineStatus(this, board);
initializePositionCounts(board);
}
@Override
public EyeInformation getInformation() {
return information_;
}
@Override
public EyeStatus getStatus() {
return status_;
}
@Override
public String getEyeTypeName() {
if (information_ == null)
return "unknown eye type";
return information_.getTypeName();
}
@Override
public int getNumCornerPoints() {
return numCornerPoints_;
}
@Override
public int getNumEdgePoints() {
return numEdgePoints_;
}
@Override
protected void initializeMembers() {
members_ = new GoBoardPositionSet();
}
private void initializePositionCounts(GoBoard board) {
numCornerPoints_ = 0;
numEdgePoints_ = 0;
for (GoBoardPosition pos : getMembers()) {
if (board.isCornerTriple(pos)) {
numCornerPoints_++;
}
if (board.isOnEdge(pos)) {
numEdgePoints_++;
}
}
}
/**
* @return the hashSet containing the members
*/
@Override
public GoBoardPositionSet getMembers() {
return members_;
}
/**
* @return true if the piece is an enemy of the string owner.
* If the difference in health between the stones is great, then they are not really enemies
* because one of them is dead. I used to do the "much weaker" test here but the group health
* info is not guaranteed to be updated yet.
*/
@Override
public boolean isEnemy(GoBoardPosition pos)
{
IGoGroup g = getGroup();
assert (g != null): "group for "+ this +" is null";
if (pos.isUnoccupied()) {
return false;
}
GoStone stone = (GoStone)pos.getPiece();
assert (g.isOwnedByPlayer1() == isOwnedByPlayer1()):
"Bad group ownership for eye="+ this +". Owning Group="+g;
return (stone.isOwnedByPlayer1() != isOwnedByPlayer1()); // && !weaker);
}
/**
* Add a space to the eye string.
* The space is either blank or a dead enemy stone.
* Called only during initial construction.
*/
@Override
protected void addMemberInternal(GoBoardPosition space, GoBoard board) {
if ( getMembers().contains( space ) ) {
GameContext.log(1, "Warning: the eye, " + this + ", already contains " + space);
assert ( (space.getString() == null) || (this == space.getString())):
"bad space or bad owning string" + space.getString();
}
space.setEye( this );
getMembers().add( space );
}
@Override
public void clear() {
for (GoBoardPosition pos : getMembers()) {
pos.setEye(null);
pos.setVisited(false);
}
setGroup(null);
getMembers().clear();
}
public String toString() {
return new EyeSerializer(this).serialize();
}
@Override
protected String getPrintPrefix() {
return " Eye: " + getEyeTypeName() + ": ";
}
}