/*
* Copyright 2013 MovingBlocks
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.terasology.entitySystem.entity.internal;
import com.google.common.collect.Sets;
import org.terasology.entitySystem.Component;
import org.terasology.entitySystem.entity.EntityRef;
import org.terasology.entitySystem.metadata.ComponentFieldMetadata;
import org.terasology.entitySystem.metadata.ComponentLibrary;
import org.terasology.entitySystem.metadata.ComponentMetadata;
import java.util.Collection;
import java.util.Map;
import java.util.Set;
/**
* @author Immortius
*/
public final class OwnershipHelper {
private ComponentLibrary componentLibrary;
public OwnershipHelper(ComponentLibrary componentLibrary) {
this.componentLibrary = componentLibrary;
}
/**
* Produces a collection of entities that are owned by the provided entity.
* This is immediate ownership only - it does not recursively follow ownership.
*
* @param entity The owning entity
* @return A collection of owned entities of the given entity
*/
public Collection<EntityRef> listOwnedEntities(EntityRef entity) {
Set<EntityRef> entityRefList = Sets.newHashSet();
for (ComponentMetadata<?> componentMetadata : componentLibrary.iterateComponentMetadata()) {
if (componentMetadata.isReferenceOwner()) {
Component comp = entity.getComponent(componentMetadata.getType());
if (comp != null) {
addOwnedEntitiesFor(comp, componentMetadata, entityRefList);
}
}
}
return entityRefList;
}
public Collection<EntityRef> listOwnedEntities(Component component) {
Set<EntityRef> entityRefList = Sets.newHashSet();
addOwnedEntitiesFor(component, componentLibrary.getMetadata(component.getClass()), entityRefList);
return entityRefList;
}
@SuppressWarnings("unchecked")
private void addOwnedEntitiesFor(Component comp, ComponentMetadata<?> componentMetadata, Collection<EntityRef> outEntityList) {
for (ComponentFieldMetadata field : componentMetadata.getFields()) {
if (field.isOwnedReference()) {
Object value = field.getValue(comp);
if (value instanceof Collection) {
for (EntityRef ref : ((Collection<EntityRef>) value)) {
if (ref.exists()) {
outEntityList.add(ref);
}
}
} else if (value instanceof Map) {
for (EntityRef ref : ((Map<Object, EntityRef>) value).values()) {
if (ref.exists()) {
outEntityList.add(ref);
}
}
} else if (value instanceof EntityRef) {
EntityRef ref = (EntityRef) value;
if (ref.exists()) {
outEntityList.add(ref);
}
}
}
}
}
}