/**
    * This file Copyright (c) 2003-2010 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.module.webapp;
  
  import info.magnolia.cms.beans.config.ContentRepository;
  import info.magnolia.module.InstallContext;
  import info.magnolia.module.ModuleVersionHandler;
  import info.magnolia.module.delta.Delta;
  import info.magnolia.module.delta.DeltaBuilder;
  import info.magnolia.module.delta.Task;
  import info.magnolia.module.model.Version;
  
  import javax.jcr.RepositoryException;
  import java.util.Collections;
  import java.util.List;
  
  /**
   *
   * @author gjoseph
   * @version $Revision: $ ($Author: $)
   */
  public class WebappVersionHandler implements ModuleVersionHandler {
      private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(WebappVersionHandler.class);
  
      public Version getCurrentlyInstalled(InstallContext ctx) {
          try {
              final boolean anyContent = ContentRepository.checkIfInitialized();
              log.info("Content was {}found in the repository, will {}bootstrap web-app.", (anyContent ? "" : "not "), (anyContent ? "not " : ""));
              if (anyContent) {
                  return Version.UNDEFINED_TO;
              } else {
                  // no content, so we'll execute.
                  return null;
              }
  
          } catch (RepositoryException e) {
              //TODO
              throw new RuntimeException("Couldn't check if repositories were empty: " + e.getMessage(), e);
          }
      }
  
      public List<Delta> getDeltas(InstallContext ctx, Version from) {
          if (from == null) {
              final Version version = ctx.getCurrentModuleDefinition().getVersion();
              return Collections.<Delta>singletonList(new WebappDelta(version));
          } else if (!from.equals(Version.UNDEFINED_TO)) {
              throw new IllegalStateException("This is a dummy module. It should not get updated.");
          } else {
              return Collections.emptyList();
          }
      }
  
      public Delta getStartupDelta(InstallContext ctx) {
          return DeltaBuilder.startup(ctx.getCurrentModuleDefinition(), Collections.<Task>emptyList());
      }
  }