/*************************************************************************
 * Copyright 2009-2012 Eucalyptus Systems, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 3 of the License.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/.
 *
 * Please contact Eucalyptus Systems, Inc., 6755 Hollister Ave., Goleta
 * CA 93117, USA or visit http://www.eucalyptus.com/licenses/ if you need
 * additional information or have any questions.
 *
 * This file may incorporate work covered under the following copyright
 * and permission notice:
 *
 *   Software License Agreement (BSD License)
 *
 *   Copyright (c) 2008, Regents of the University of California
 *   All rights reserved.
 *
 *   Redistribution and use of this software in source and binary forms,
 *   with or without modification, are permitted provided that the
 *   following conditions are met:
 *
 *     Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *     Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer
 *     in the documentation and/or other materials provided with the
 *     distribution.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *   COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *   CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *   LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *   ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *   POSSIBILITY OF SUCH DAMAGE. USERS OF THIS SOFTWARE ACKNOWLEDGE
 *   THE POSSIBLE PRESENCE OF OTHER OPEN SOURCE LICENSED MATERIAL,
 *   COPYRIGHTED MATERIAL OR PATENTED MATERIAL IN THIS SOFTWARE,
 *   AND IF ANY SUCH MATERIAL IS DISCOVERED THE PARTY DISCOVERING
 *   IT MAY INFORM DR. RICH WOLSKI AT THE UNIVERSITY OF CALIFORNIA,
 *   SANTA BARBARA WHO WILL THEN ASCERTAIN THE MOST APPROPRIATE REMEDY,
 *   WHICH IN THE REGENTS' DISCRETION MAY INCLUDE, WITHOUT LIMITATION,
 *   REPLACEMENT OF THE CODE SO IDENTIFIED, LICENSING OF THE CODE SO
 *   IDENTIFIED, OR WITHDRAWAL OF THE CODE CAPABILITY TO THE EXTENT
 *   NEEDED TO COMPLY WITH ANY SUCH LICENSES OR RIGHTS.
 ************************************************************************/

package com.eucalyptus.blockstorage;

import javax.persistence.EntityTransaction;

import org.apache.log4j.Logger;

import com.eucalyptus.blockstorage.config.StorageControllerConfiguration;
import com.eucalyptus.component.Components;
import com.eucalyptus.entities.Entities;
import com.google.common.base.Strings;

@Deprecated
public class BlockStorageManagerFactory {
  private static Logger LOG = Logger.getLogger(BlockStorageManagerFactory.class);

  public static LogicalStorageManager getBlockStorageManager() throws Exception {
    // Get the basic service config, but this is stale, so we must query the db directly
    StorageControllerConfiguration scServiceConfig =
        (StorageControllerConfiguration) (Components.lookup(Storage.class).getLocalServiceConfiguration());
    if (scServiceConfig == null) {
      throw new ClassNotFoundException("Cannot lookup SC config because partition or service name is not found");
    }

    // Get the latest info from the DB directly.
    StorageControllerConfiguration exampleConfig = new StorageControllerConfiguration();
    exampleConfig.setPartition(scServiceConfig.getPartition());
    exampleConfig.setName(scServiceConfig.getName());
    exampleConfig.setHostName(scServiceConfig.getHostName());

    EntityTransaction trans = Entities.get(StorageControllerConfiguration.class);
    StorageControllerConfiguration scInfo = null;
    try {
      scInfo = Entities.uniqueResult(exampleConfig);
    } catch (Exception e) {
      throw new ClassNotFoundException("Error retrieving configuration for this SC: " + exampleConfig.getPartition() + " " + exampleConfig.getName(),
          e);
    } finally {
      trans.commit();
    }

    String ebsManager = scInfo.getBlockStorageManager();
    if (Strings.isNullOrEmpty(ebsManager)) {
      LOG.error("No block storage backend specified.");
      throw new ClassNotFoundException("Block Storage Backend not specified");
    }

    // Update the in-memory state of the service config
    scServiceConfig.setBlockStorageManager(scInfo.getBlockStorageManager());

    try {
      ebsManager = "com.eucalyptus.storage." + ebsManager;
      return (LogicalStorageManager) ClassLoader.getSystemClassLoader().loadClass(ebsManager).newInstance();
    } catch (ClassNotFoundException e) {
      LOG.error("No such backend: " + ebsManager + ". Did you spell it correctly? " + e);
      throw e;
    }
  }
}