/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */

package org.hibernate.cache.jcache.access;

import org.hibernate.cache.CacheException;
import org.hibernate.cache.internal.DefaultCacheKeysFactory;
import org.hibernate.cache.jcache.JCacheNaturalIdRegion;
import org.hibernate.cache.spi.access.NaturalIdRegionAccessStrategy;
import org.hibernate.cache.spi.access.SoftLock;
import org.hibernate.engine.spi.SharedSessionContractImplementor;
import org.hibernate.persister.entity.EntityPersister;

/**
 * @author Alex Snaps
 */
public class ReadWriteNaturalIdRegionAccessStrategy
		extends AbstractReadWriteRegionAccessStrategy<JCacheNaturalIdRegion>
		implements NaturalIdRegionAccessStrategy {

	public ReadWriteNaturalIdRegionAccessStrategy(JCacheNaturalIdRegion jCacheNaturalIdRegion) {
		super ( jCacheNaturalIdRegion );
	}

	@Override
	public boolean insert(SharedSessionContractImplementor session, Object key, Object value) throws CacheException {
		return false;
	}

	@Override
	public boolean afterInsert(SharedSessionContractImplementor session, Object key, Object value) throws CacheException {
		return region.putIfAbsent( key, new Item( value, null, region.nextTimestamp(), nextItemId() ));
	}

	@Override
	public boolean update(SharedSessionContractImplementor session, Object key, Object value)
			throws CacheException {
		return false;
	}

	@Override
	public boolean afterUpdate(SharedSessionContractImplementor session, Object key, Object value, SoftLock lock)
			throws CacheException {
		while (true) {
			Lockable item = (Lockable) region.get( key );

			if ( item != null && item.isUnlockable( lock ) ) {
				final Lock lockItem = (Lock) item;
				if ( lockItem.wasLockedConcurrently() ) {
					if (region.replace( key, lockItem, lockItem.unlock( region.nextTimestamp() ) )) {
						return false;
					}
				}
				else {
					if (region.replace( key, lockItem, new Item(value, null, region.nextTimestamp(), nextItemId() ))) {
						return true;
					}
				}
			}
			else {
				handleMissingLock( key, item );
				return false;
			}

		}
	}

	@Override
	public Object generateCacheKey(Object[] naturalIdValues, EntityPersister persister, SharedSessionContractImplementor session) {
		return DefaultCacheKeysFactory.staticCreateNaturalIdKey( naturalIdValues, persister, session );
	}

	@Override
	public Object[] getNaturalIdValues(Object cacheKey) {
		return DefaultCacheKeysFactory.staticGetNaturalIdValues( cacheKey );
	}
}