/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2011, Red Hat Inc. or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Inc.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 */
package org.hibernate.cache.internal;

import java.util.Map;
import java.util.Properties;

import org.hibernate.HibernateException;
import org.hibernate.boot.registry.StandardServiceInitiator;
import org.hibernate.boot.registry.selector.spi.StrategySelector;
import org.hibernate.cache.spi.RegionFactory;
import org.hibernate.cfg.AvailableSettings;
import org.hibernate.internal.CoreMessageLogger;
import org.hibernate.internal.util.config.ConfigurationHelper;
import org.hibernate.service.spi.ServiceRegistryImplementor;

import org.jboss.logging.Logger;

Initiator for the RegionFactory service. 
Author:
Hardy Ferentschik, Brett Meyer/**
 * Initiator for the {@link RegionFactory} service.
 * 
 * @author Hardy Ferentschik
 * @author Brett Meyer
 */
public class RegionFactoryInitiator implements StandardServiceInitiator<RegionFactory> {

	private static final CoreMessageLogger LOG = Logger.getMessageLogger( CoreMessageLogger.class,
			RegionFactoryInitiator.class.getName() );

	
Singleton access
/**
	 * Singleton access
	 */
	public static final RegionFactoryInitiator INSTANCE = new RegionFactoryInitiator();

	@Override
	public Class<RegionFactory> getServiceInitiated() {
		return RegionFactory.class;
	}

	@Override
	@SuppressWarnings({ "unchecked" })
	public RegionFactory initiateService(Map configurationValues, ServiceRegistryImplementor registry) {
		final Properties p = new Properties();
		if (configurationValues != null) {
			p.putAll( configurationValues );
		}
		
		final boolean useSecondLevelCache = ConfigurationHelper.getBoolean(
				AvailableSettings.USE_SECOND_LEVEL_CACHE,
				configurationValues,
				true
		);
		final boolean useQueryCache = ConfigurationHelper.getBoolean(
				AvailableSettings.USE_QUERY_CACHE,
				configurationValues
		);

		RegionFactory regionFactory = NoCachingRegionFactory.INSTANCE;

		// The cache provider is needed when we either have second-level cache enabled
		// or query cache enabled.  Note that useSecondLevelCache is enabled by default
		final String setting = ConfigurationHelper.getString( AvailableSettings.CACHE_REGION_FACTORY,
				configurationValues, null );
		if ( ( useSecondLevelCache || useQueryCache ) && setting != null ) {
			try {
				final Class<? extends RegionFactory> regionFactoryClass = registry.getService( StrategySelector.class )
						.selectStrategyImplementor( RegionFactory.class, setting );
				try {
					regionFactory = regionFactoryClass.getConstructor( Properties.class ).newInstance( p );
				}
				catch ( NoSuchMethodException e ) {
					// no constructor accepting Properties found, try no arg constructor
					LOG.debugf(
							"%s did not provide constructor accepting java.util.Properties; attempting no-arg constructor.",
							regionFactoryClass.getSimpleName() );
					regionFactory = regionFactoryClass.getConstructor().newInstance();
				}
			}
			catch ( Exception e ) {
				throw new HibernateException( "could not instantiate RegionFactory [" + setting + "]", e );
			}
		}

		LOG.debugf( "Cache region factory : %s", regionFactory.getClass().getName() );

		return regionFactory;
	}

	
Map legacy names unto the new corollary.
TODO: temporary hack for org.hibernate.cfg.SettingsFactory.createRegionFactory()
Params:
name – The (possibly legacy) factory name
Returns:
The factory name to use./**
	 * Map legacy names unto the new corollary.
	 *
	 * TODO: temporary hack for org.hibernate.cfg.SettingsFactory.createRegionFactory()
	 *
	 * @param name The (possibly legacy) factory name
	 *
	 * @return The factory name to use.
	 */
	public static String mapLegacyNames(final String name) {
		if ( "org.hibernate.cache.EhCacheRegionFactory".equals( name ) ) {
			return "org.hibernate.cache.ehcache.EhCacheRegionFactory";
		}

		if ( "org.hibernate.cache.SingletonEhCacheRegionFactory".equals( name ) ) {
			return "org.hibernate.cache.ehcache.SingletonEhCacheRegionFactory";
		}

		return name;
	}
}