mage/Mage/src/main/java/mage/MageObjectReference.java

package mage;

import mage.cards.Card;
import mage.constants.Zone;
import mage.game.Game;
import mage.game.permanent.Permanent;
import mage.game.stack.Spell;
import mage.game.stack.StackObject;
import org.apache.log4j.Logger;

import java.io.Serializable;
import java.util.Objects;
import java.util.UUID;

/**
 * A object reference that takes zone changes into account.
 *
 * @author LevelX2
 */
public class MageObjectReference implements Comparable<MageObjectReference>, Serializable {

    private static final Logger logger = Logger.getLogger(MageObjectReference.class);

    private final UUID sourceId;
    private final int zoneChangeCounter;

    public MageObjectReference(MageObject mageObject, Game game) {
        if (mageObject == null) {
            this.sourceId = null;
            this.zoneChangeCounter = -1;
            return;
        }
        this.sourceId = mageObject.getId();
        this.zoneChangeCounter = mageObject.getZoneChangeCounter(game);
    }

    /**
     * That values manually (can be used to let it reference to a Permanent that
     * is not yet on the battlefield.
     *
     * @param sourceId          can be null
     * @param zoneChangeCounter
     * @param game
     */
    public MageObjectReference(UUID sourceId, int zoneChangeCounter, Game game) {
        this.sourceId = sourceId;
        this.zoneChangeCounter = zoneChangeCounter;
    }

    public MageObjectReference(UUID sourceId) {
        this.sourceId = sourceId;
        this.zoneChangeCounter = -1;
    }

    /**
     * @param sourceId can be null
     * @param game
     */
    public MageObjectReference(UUID sourceId, Game game) {
        this.sourceId = sourceId;
        if (sourceId == null) {
            this.zoneChangeCounter = -1;
            return;
        }

        MageObject mageObject = game.getObject(sourceId);
        if (mageObject != null) {
            this.zoneChangeCounter = mageObject.getZoneChangeCounter(game);
        } else {
            if (game.getPlayerList().contains(sourceId)) {
                this.zoneChangeCounter = 0;
            } else {
                logger.error("The provided sourceId is not connected to an object in the game id: " + sourceId);
                for (StackObject stackObject : game.getStack()) {
                    logger.error("StackObject: " + stackObject.getId() + " sourceId " + stackObject.getSourceId() + " name " + stackObject.getName());
                }
                mageObject = game.getLastKnownInformation(sourceId, Zone.STACK);
                if (mageObject != null) {
                    this.zoneChangeCounter = mageObject.getZoneChangeCounter(game);
                    logger.error("SourceId found in LKI");
                } else {
                    this.zoneChangeCounter = 0;
                    logger.error("SourceId NOT found in LKI");
                }
            }
        }
    }

    public UUID getSourceId() {
        return sourceId;
    }

    public int getZoneChangeCounter() {
        return zoneChangeCounter;
    }

    @Override
    public int compareTo(MageObjectReference o) {
        if (o.getSourceId() == null || this.sourceId == null || Objects.equals(o.getSourceId(), this.sourceId)) {
            return o.getZoneChangeCounter() - this.zoneChangeCounter;
        }
        return o.getSourceId().compareTo(sourceId);
    }

    @Override
    public boolean equals(Object v) {
        if (v instanceof MageObjectReference) {
            if (Objects.equals(((MageObjectReference) v).getSourceId(), this.sourceId)) {
                return ((MageObjectReference) v).getZoneChangeCounter() == this.zoneChangeCounter;
            }
        }
        return false;
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 17 * hash + (this.sourceId != null ? this.sourceId.hashCode() + this.zoneChangeCounter : 0);
        return hash;
    }

    public boolean refersTo(UUID id, Game game) {
        return refersTo(game.getObject(id), game);
    }

    public boolean refersTo(MageObject mageObject, Game game) {
        if (mageObject != null) {
            if (mageObject instanceof Spell) {
                return Objects.equals(((Spell) mageObject).getSourceId(), this.sourceId) && this.zoneChangeCounter == mageObject.getZoneChangeCounter(game);
            }
            return mageObject.getId().equals(sourceId) && this.zoneChangeCounter == mageObject.getZoneChangeCounter(game);
        }
        return false;
    }

    public Permanent getPermanent(Game game) {
        Permanent permanent = game.getPermanent(sourceId);
        if (permanent != null && permanent.getZoneChangeCounter(game) == zoneChangeCounter) {
            return permanent;
        }
        return null;
    }

    public Permanent getPermanentOrLKIBattlefield(Game game) {
        Permanent permanent = game.getPermanentOrLKIBattlefield(sourceId);
        if (permanent != null && permanent.getZoneChangeCounter(game) == zoneChangeCounter) {
            return permanent;
        }
        return null;
    }

    public Card getCard(Game game) {
        Card card = game.getCard(sourceId);
        if (card != null && card.getZoneChangeCounter(game) == zoneChangeCounter) {
            return card;
        }
        return null;
    }

    public boolean zoneCounterIsCurrent(Game game) {
        return game.getState().getZoneChangeCounter(sourceId) == zoneChangeCounter;
    }
}