/**
    * This file Copyright (c) 2013 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.setup.for5_2;
  
  import info.magnolia.jcr.predicate.NodeTypePredicate;
  import info.magnolia.jcr.util.NodeUtil;
  import info.magnolia.jcr.util.NodeVisitor;
  import info.magnolia.module.InstallContext;
  import info.magnolia.module.delta.AbstractRepositoryTask;
  import info.magnolia.module.delta.TaskExecutionException;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import javax.jcr.Node;
  import javax.jcr.RepositoryException;
  import javax.jcr.Session;
  
  import org.apache.commons.lang.StringUtils;
  import org.apache.jackrabbit.JcrConstants;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Identify all sibling nodes for a defined workspace, sub path and nodeTypes.<br>
   * If the nodesTypes is empty or null, search all 'nt:base' nodes.
   */
  public class IdentifySameNameSiblingNodesTask extends AbstractRepositoryTask {
      private static final Logger log = LoggerFactory.getLogger(IdentifySameNameSiblingNodesTask.class);
  
      protected final String workspace;
      protected Session session;
      private final String subPath;
      private final List<String> nodeTypes;
      private final boolean evaluateSupertypes;
      private final String siblingMatcherPattern = ".*\\[\\d+\\]";
  
      /**
       * @param name task name
       * @param description task description
       * @param workspace task is running against this workspace. TaskExecutionException is throws if the workspace is invalid or null.
       * @param subPath used to limit the operation to a specified subPath '/demo-project/about'
       * @param nodeTypes List of nodeTypes that has to search. If null or empty, the search of siblings is performed against 'nt:base'
       * @param evaluateSupertypes if set to true, the child nodeTypes of a defined 'nodeType' are also part of the evaluation.
       */
      public IdentifySameNameSiblingNodesTask(String name, String description, String workspace, String subPath, List<String> nodeTypes, boolean evaluateSupertypes) {
          super(name, description);
          this.workspace = workspace;
          this.subPath = StringUtils.isBlank(subPath) ? "/" : subPath;
          this.nodeTypes = nodeTypes != null ? nodeTypes : new ArrayList<String>();
          this.evaluateSupertypes = evaluateSupertypes;
      }
  
      @Override
      protected void doExecute(InstallContext installContext) throws RepositoryException, TaskExecutionException {
          try{
              session = installContext.getJCRSession(workspace);
              // Check
              if (nodeTypes.isEmpty()) {
                  nodeTypes.add(JcrConstants.NT_BASE);
              }
              for (String nodeType : nodeTypes) {
                  Node rootNode = session.getNode(subPath);
                  NodeTypePredicate predicate = new NodeTypePredicate(nodeType, evaluateSupertypes);
                  NodeUtil.visit(rootNode, createSiblingsVisitor(installContext), predicate);
  
              }
          }catch(RepositoryException re) {
             installContext.error("Unable to perform Migration task " + getName(), re);
             throw new TaskExecutionException(re.getMessage());
         }
 
     }
 
     /**
      * Create a Siblings visitor.
      */
     private NodeVisitor createSiblingsVisitor(final InstallContext installContext) {
         NodeVisitor visitor = new NodeVisitor() {
 
             @Override
             public void visit(Node node) throws RepositoryException {
                 if (isSameNameSiblingNode(node)) {
                     handleNode(node, installContext);
                 }
             }
         };
         return visitor;
     }
 
     /**
      * Return true if the node match the siblingMatcherPattern.
      */
     protected boolean isSameNameSiblingNode(Node node) {
         try {
             String path = node.getPath();
             return path.matches(siblingMatcherPattern);
         } catch (RepositoryException re) {
             log.warn("Got exception by checking if '{}' is a sibling node", NodeUtil.getName(node), re);
             return false;
         }
     }
 
     /**
      * Take action on a sibling node.<br>
      * In this case, simply display in the install screen the sibling node name and path.
      */
     protected void handleNode(Node node, InstallContext installContext) throws RepositoryException {
         installContext.warn("Found same name sibling of '" + node.getName() + "' at '" + node.getPath() + "'");
     }
 
 }