/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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.
*
* Copyright (c) 2006 - 2013 Pentaho Corporation and Contributors.  All rights reserved.
*/

package org.pentaho.reporting.libraries.resourceloader.modules.cache.ehcache;

import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheException;
import net.sf.ehcache.CacheManager;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.pentaho.reporting.libraries.resourceloader.cache.ResourceBundleDataCache;
import org.pentaho.reporting.libraries.resourceloader.cache.ResourceBundleDataCacheProvider;
import org.pentaho.reporting.libraries.resourceloader.cache.ResourceDataCache;
import org.pentaho.reporting.libraries.resourceloader.cache.ResourceDataCacheProvider;
import org.pentaho.reporting.libraries.resourceloader.cache.ResourceFactoryCache;
import org.pentaho.reporting.libraries.resourceloader.cache.ResourceFactoryCacheProvider;

public class EHCacheProvider implements ResourceDataCacheProvider,
  ResourceFactoryCacheProvider, ResourceBundleDataCacheProvider {
  private static CacheManager cacheManager;

  private static final String DATA_CACHE_NAME = "libloader-data";
  private static final String BUNDLES_CACHE_NAME = "libloader-bundles";
  private static final String FACTORY_CACHE_NAME = "libloader-factory";

  private static final Log logger = LogFactory.getLog( EHCacheProvider.class );

  public static synchronized CacheManager getCacheManager() throws CacheException {
    if ( cacheManager == null ) {
      cacheManager = CacheManager.getInstance();
    }
    return cacheManager;
  }

  public EHCacheProvider() {
  }

  public ResourceDataCache createDataCache() {
    try {
      final CacheManager manager = getCacheManager();
      synchronized( manager ) {
        if ( manager.cacheExists( DATA_CACHE_NAME ) == false ) {
          final Cache libloaderCache = new Cache( DATA_CACHE_NAME,   // cache name
            500,         // maxElementsInMemory
            false,       // overflowToDisk
            false,       // eternal
            600,         // timeToLiveSeconds
            600,         // timeToIdleSeconds
            false,       // diskPersistent
            120 );        // diskExpiryThreadIntervalSeconds
          manager.addCache( libloaderCache );
          return new EHResourceDataCache( libloaderCache );
        } else {
          return new EHResourceDataCache( manager.getCache( DATA_CACHE_NAME ) );
        }
      }
    } catch ( CacheException e ) {
      logger.debug( "Failed to create EHCache libloader-data cache", e );
      return null;
    }
  }

  public ResourceBundleDataCache createBundleDataCache() {
    try {
      final CacheManager manager = getCacheManager();
      synchronized( manager ) {
        if ( manager.cacheExists( BUNDLES_CACHE_NAME ) == false ) {
          final Cache libloaderCache = new Cache( BUNDLES_CACHE_NAME,   // cache name
            500,         // maxElementsInMemory
            false,       // overflowToDisk
            false,       // eternal
            600,         // timeToLiveSeconds
            600,         // timeToIdleSeconds
            false,       // diskPersistent
            120 );        // diskExpiryThreadIntervalSeconds
          manager.addCache( libloaderCache );
          return new EHResourceBundleDataCache( libloaderCache );
        } else {
          return new EHResourceBundleDataCache( manager.getCache( BUNDLES_CACHE_NAME ) );
        }
      }
    } catch ( CacheException e ) {
      logger.debug( "Failed to create EHCache libloader-bundles cache", e );
      return null;
    }
  }

  public ResourceFactoryCache createFactoryCache() {
    try {
      final CacheManager manager = getCacheManager();
      synchronized( manager ) {
        if ( manager.cacheExists( FACTORY_CACHE_NAME ) == false ) {
          final Cache libloaderCache = new Cache( FACTORY_CACHE_NAME,   // cache name
            500,         // maxElementsInMemory
            false,       // overflowToDisk
            false,       // eternal
            600,         // timeToLiveSeconds
            600,         // timeToIdleSeconds
            false,       // diskPersistent
            120 );        // diskExpiryThreadIntervalSeconds
          manager.addCache( libloaderCache );
          return new EHResourceFactoryCache( libloaderCache );
        } else {
          return new EHResourceFactoryCache( manager.getCache( FACTORY_CACHE_NAME ) );
        }
      }
    } catch ( CacheException e ) {
      logger.debug( "Failed to create EHCache libloader-factory cache", e );
      return null;
    }
  }
}