/*
 * Copyright (C) 2009 eXo Platform SAS.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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 software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.exoplatform.services.jcr.ext.backup.impl;

import org.exoplatform.services.jcr.RepositoryService;
import org.exoplatform.services.jcr.config.RepositoryEntry;
import org.exoplatform.services.jcr.config.WorkspaceEntry;
import org.exoplatform.services.jcr.core.ManageableRepository;
import org.exoplatform.services.jcr.core.WorkspaceContainerFacade;
import org.exoplatform.services.jcr.ext.backup.BackupChainLog;
import org.exoplatform.services.jcr.ext.backup.BackupManager;
import org.exoplatform.services.jcr.ext.backup.server.WorkspaceRestoreExeption;
import org.exoplatform.services.jcr.impl.core.RepositoryImpl;
import org.exoplatform.services.jcr.impl.core.SessionRegistry;
import org.exoplatform.services.log.ExoLogger;
import org.exoplatform.services.log.Log;

import java.util.Calendar;

import javax.jcr.InvalidItemStateException;
import javax.jcr.RepositoryException;

/**
 * Created by The eXo Platform SAS.
 * 
 * <br/>Date: 24.02.2009
 * 
 * @author <a href="mailto:alex.reshetnyak@exoplatform.com.ua">Alex Reshetnyak</a>
 * @version $Id: WorkspaceRestore.java 111 2008-11-11 11:11:11Z rainf0x $
 */
public class JobWorkspaceRestore extends Thread
{

   /**
    * The apache logger.
    */
   private static Log log = ExoLogger.getLogger("exo.jcr.component.ext.JobWorkspaceRestore");

   /**
    * RESTORE_STARTED. The state of start restore.
    */
   public static final int RESTORE_STARTED = 1;

   /**
    * RESTORE_SUCCESSFUL. The state of restore successful.
    */
   public static final int RESTORE_SUCCESSFUL = 2;

   /**
    * RESTORE_FAIL. The state of restore fail.
    */
   public static final int RESTORE_FAIL = 3;

   /**
    * RESTORE_STARTED. The state of initialized restore.
    */
   public static final int RESTORE_INITIALIZED = 4;

   /**
    * The state of restore.
    */
   private int stateRestore;

   /**
    * The destination repository.
    */
   protected final String repositoryName;

   /**
    * The WorkspaceEntry to restored workspace.
    */
   protected final WorkspaceEntry wEntry;

   /**
    * The repository service.
    */
   protected final RepositoryService repositoryService;

   /**
    * The backup manager.
    */
   private final BackupManager backupManager;

   /**
    * The exception on restore.
    */
   private Throwable restoreException = null;

   /**
    * The start time of restore.
    */
   private Calendar startTime;

   /**
    * The end time of restore.
    */
   private Calendar endTime;

   /**
    * The BackupChainLog for restore.
    */
   private final BackupChainLog backupChainLog;

   /**
    * JobWorkspaceRestore constructor.
    * 
    * @param repositoryService
    *          the RepositoryService
    * @param backupManager
    *          the BackupManager
    * @param repositoryName
    *          the destination repository
    * @param log
    *          the backup chain log
    * @param wEntry 
    *          the workspace entry
    */
   public JobWorkspaceRestore(RepositoryService repositoryService, BackupManager backupManager, String repositoryName,
      BackupChainLog log, WorkspaceEntry wEntry)
   {
      this.repositoryService = repositoryService;
      this.backupManager = backupManager;
      this.repositoryName = repositoryName;
      this.backupChainLog = log;
      this.wEntry = wEntry;
      this.stateRestore = RESTORE_INITIALIZED;
   }

   /**
    * {@inheritDoc}
    */
   public void run()
   {
      try
      {
         stateRestore = RESTORE_STARTED;
         startTime = Calendar.getInstance();

         restore();

         stateRestore = RESTORE_SUCCESSFUL;
         endTime = Calendar.getInstance();
      }
      catch (Throwable t)
      {
         stateRestore = RESTORE_FAIL;
         restoreException = t;

         log.error("The restore was fail", t);
      }
   }

   /**
    * Will be restored the workspace.
    * 
    * @throws Throwable
    *           will be generated the Throwable
    */
   protected void restore() throws Throwable
   {
      boolean restored = true;
      RepositoryImpl repository = (RepositoryImpl)repositoryService.getRepository(repositoryName);
      try
      {
         RepositoryEntry reEntry = repository.getConfiguration();
         backupManager.restore(backupChainLog, reEntry.getName(), wEntry, false);
      }
      catch (InvalidItemStateException e)
      {
         restored = false;
         throw new WorkspaceRestoreExeption("Workspace '" + "/" + repositoryName + "/" + wEntry.getName()
            + "' can not be restored! There was database error!", e);

      }
      catch (Throwable t)
      {
         restored = false;
         throw new WorkspaceRestoreExeption("Workspace '" + "/" + repositoryName + "/" + wEntry.getName()
            + "' can not be restored!", t);

      }
      finally
      {
         if (!restored)
         {
            try
            {
               removeWorkspace(repository, wEntry.getName());
            }
            catch (Throwable thr)
            {
               throw new WorkspaceRestoreExeption("Workspace '" + "/" + repositoryName + "/"
                  + wEntry.getName() + "' can not be restored!", thr);
            }
         }
      }

   }

   /**
    * removeWorkspace.
    *
    * @param mr
    *          ManageableRepository, the manageable repository
    * @param workspaceName
    *          String, the workspace name
    * @throws RepositoryException
    *           will be generated the RepositoryException
    */
   private void removeWorkspace(ManageableRepository mr, String workspaceName) throws RepositoryException
   {

      boolean isExists = false;
      for (String wsName : mr.getWorkspaceNames())
         if (workspaceName.equals(wsName))
         {
            isExists = true;
            break;
         }

      if (isExists)
      {
         if (!mr.canRemoveWorkspace(workspaceName))
         {
            WorkspaceContainerFacade wc = mr.getWorkspaceContainer(workspaceName);
            SessionRegistry sessionRegistry = (SessionRegistry)wc.getComponent(SessionRegistry.class);
            sessionRegistry.closeSessions(workspaceName);
         }

         mr.removeWorkspace(workspaceName);
      }
   }

   /**
    * getRestoreException.
    * 
    * @return Throwable return the exception of restore.
    */
   public Throwable getRestoreException()
   {
      return restoreException;
   }

   /**
    * getStateRestore.
    * 
    * @return int return state of restore.
    */
   public int getStateRestore()
   {
      return stateRestore;
   }

   /**
    * getBeginTime.
    * 
    * @return Calendar return the start time of restore
    */
   public Calendar getStartTime()
   {
      return startTime;
   }

   /**
    * getEndTime.
    * 
    * @return Calendar return the end time of restore
    */
   public Calendar getEndTime()
   {
      return endTime;
   }

   /**
    * getBackupChainLog.
    *
    * @return BackupChainLog
    *           return the backup chain log for this restore.
    */
   public BackupChainLog getBackupChainLog()
   {
      return backupChainLog;
   }

   /**
    * getRepositoryName.
    *
    * @return String
    *           the name of destination repository
    */
   public String getRepositoryName()
   {
      return repositoryName;
   }

   /**
    * getWorkspaceName.
    *
    * @return String
    *           the name of destination workspace
    */
   public String getWorkspaceName()
   {
      return wEntry.getName();
   }

   /**
    * getWorkspaceEntry
    * 
    * @return WorkspaceEntry
    * 
    */
   public WorkspaceEntry getWorkspaceEntry()
   {
      return wEntry;
   }

}
