/*
* Copyright 2016 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.inmemory;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import gnu.trove.TCollections;
import gnu.trove.iterator.TLongIterator;
import gnu.trove.iterator.TLongObjectIterator;
import gnu.trove.map.TLongObjectMap;
import gnu.trove.map.hash.TLongObjectHashMap;
import gnu.trove.set.TLongSet;
import gnu.trove.set.hash.TLongHashSet;
import org.terasology.entitysystem.Component;
import org.terasology.entitysystem.component.ComponentManager;
import java.util.Collection;
import java.util.List;
import java.util.Map;
/**
* A table for storing entities and components. Focused on allowing iteration across a components of a given type
*
* @author Immortius
*/
class ComponentTable implements EntityStore {
private Map<Class, TLongObjectMap<Component>> store = Maps.newConcurrentMap();
private ComponentManager componentManager;
public ComponentTable(ComponentManager componentManager) {
this.componentManager = componentManager;
}
@Override
public <T extends Component> T get(long entityId, Class<T> componentClass) {
TLongObjectMap<Component> entityMap = store.get(componentClass);
if (entityMap != null) {
return componentManager.copy(componentClass.cast(entityMap.get(entityId)));
}
return null;
}
@Override
public synchronized <T extends Component> boolean add(long entityId, Class<T> componentType, T component) {
TLongObjectMap<Component> entityMap = store.get(componentType);
if (entityMap == null) {
entityMap = TCollections.synchronizedMap(new TLongObjectHashMap<>());
store.put(componentType, entityMap);
}
return entityMap.putIfAbsent(entityId, componentManager.copy(component)) == null;
}
@Override
public synchronized <T extends Component> boolean update(long entityId, Class<T> componentType, T component) {
TLongObjectMap<Component> entityMap = store.get(componentType);
if (entityMap == null) {
return false;
}
if (entityMap.containsKey(entityId)) {
entityMap.put(entityId, componentManager.copy(component));
return true;
}
return false;
}
/**
* @return removes the component with the specified class from the entity and returns it.
* Returns null if no component could be removed.
*/
@Override
public <T extends Component> Component remove(long entityId, Class<T> componentClass) {
TLongObjectMap<Component> entityMap = store.get(componentClass);
if (entityMap != null) {
return entityMap.remove(entityId);
}
return null;
}
@Override
public List<Component> removeAndReturnComponentsOf(long entityId) {
List<Component> componentList = Lists.newArrayList();
for (TLongObjectMap<Component> entityMap : store.values()) {
Component component = entityMap.remove(entityId);
if (component != null) {
componentList.add(component);
}
}
return componentList;
}
@Override
public void removeAll(long entityId) {
for (TLongObjectMap<Component> entityMap : store.values()) {
entityMap.remove(entityId);
}
}
@Override
public void clear() {
store.clear();
}
@Override
public int getComponentCount(Class<? extends Component> componentClass) {
TLongObjectMap<Component> map = store.get(componentClass);
return (map == null) ? 0 : map.size();
}
/**
* @return an iterable that should be only used for iteration over the components. It can't be used to remove
* components. It should not be used after components have been added or removed from the entity.
*/
@Override
public Collection<Component> getComponents(long entityId) {
List<Component> components = Lists.newArrayList();
for (TLongObjectMap<Component> componentMap : store.values()) {
Component comp = componentMap.get(entityId);
if (comp != null) {
components.add(componentManager.copy(comp));
}
}
return components;
}
@Override
public <T extends Component> TLongObjectIterator<T> componentIterator(Class<T> componentClass) {
TLongObjectMap<T> entityMap = (TLongObjectMap<T>) store.get(componentClass);
if (entityMap != null) {
return entityMap.iterator();
}
return null;
}
/**
* Produces an iterator for iterating over all entities
* <br><br>
* This is not designed to be performant, and in general usage entities should not be iterated over.
*
* @return An iterator over all entity ids.
*/
@Override
public TLongIterator entityIdIterator() {
TLongSet idSet = new TLongHashSet();
for (TLongObjectMap<Component> componentMap : store.values()) {
idSet.addAll(componentMap.keys());
}
return idSet.iterator();
}
@Override
public int entityCount() {
TLongSet idSet = new TLongHashSet();
for (TLongObjectMap<Component> componentMap : store.values()) {
idSet.addAll(componentMap.keys());
}
return idSet.size();
}
@Override
public boolean isAvailable(long entityId) {
for (TLongObjectMap<Component> componentMap : store.values()) {
Component comp = componentMap.get(entityId);
if (comp != null) {
return true;
}
}
return false;
}
}