/**
    * This file Copyright (c) 2012 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.ui.app.security.dialog.field;
  
  import com.vaadin.data.Item;
  import com.vaadin.ui.AbstractSelect;
  import com.vaadin.ui.TwinColSelect;
  import info.magnolia.cms.util.QueryUtil;
  import info.magnolia.jcr.util.NodeTypes;
  import info.magnolia.repository.RepositoryConstants;
  import info.magnolia.ui.admincentral.field.builder.TwinColSelectFieldBuilder;
  import info.magnolia.ui.model.field.definition.SelectFieldOptionDefinition;
  import info.magnolia.ui.vaadin.integration.jcr.DefaultProperty;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import javax.jcr.Node;
  import javax.jcr.NodeIterator;
  import javax.jcr.Property;
  import javax.jcr.PropertyIterator;
  import javax.jcr.RepositoryException;
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * GUI builder for the Group Management field.
   */
  public class GroupManagementField extends TwinColSelectFieldBuilder<GroupManagementFieldDefinition> {
  
      /**
       * Internal bean to represent basic group data.
       */
      public static class Group {
          public String name;
          public String uuid;
          public Group(String name, String uuid) {
              this.name = name;
              this.uuid = uuid;
          }
      }
  
      private static final Logger log = LoggerFactory.getLogger(GroupManagementField.class);
  
      public GroupManagementField(GroupManagementFieldDefinition definition, Item relatedFieldItem) {
          super(definition, relatedFieldItem);
          this.definition.setOptions(getSelectFieldOptionDefinition());
      }
  
  
      @Override
      protected AbstractSelect buildField() {
          super.buildField();
          select.setMultiSelect(true);
          select.setNullSelectionAllowed(true);
          select.setImmediate(true);
          return select;
      }
  
      @Override
      protected AbstractSelect createSelectionField() {
          return new TwinColSelect();
      }
  
      /**
       * Returns the available groups with those already assigned marked selected, according to the current node.
       */
      @Override
      public List<SelectFieldOptionDefinition> getSelectFieldOptionDefinition(){
         List<SelectFieldOptionDefinition> options = new ArrayList<SelectFieldOptionDefinition>();
         List<Group> allGroups = getAllGroups(); // name,uuid
         List<String> assignedGroups = getAssignedGroups();
         String currentUUID = null;
         try {
             currentUUID = getRelatedNode(item).getIdentifier();
         } catch (RepositoryException e) {
             // nothing to do
         }
         for (Group group : allGroups) {
             SelectFieldOptionDefinition option = new SelectFieldOptionDefinition();
             option.setValue(group.uuid);
             option.setLabel(group.name);
             if (assignedGroups.contains(group.uuid)) {
                 option.setSelected(true);
             }
             if (!group.uuid.equals(currentUUID)) {
                 // we don't want the group to be assigned to itself, do we?
                 options.add(option);
             }
         }
         return options;
     }
 
     private List<Group> getAllGroups() {
         List<Group> groups = new ArrayList<Group>();
         try {
             NodeIterator ni = QueryUtil.search(RepositoryConstants.USER_GROUPS, "SELECT * FROM ["+NodeTypes.Group.NAME+"] ORDER BY name()");
             while (ni.hasNext()) {
                 Node n = ni.nextNode();
                 String name = n.getName();
                 String uuid = n.getIdentifier();
                 groups.add(new Group(name, uuid));
             }
         } catch (RepositoryException e) {
             log.error("Cannot read groups from the ["+RepositoryConstants.USER_GROUPS+"] workspace.", e);
         }
         return groups;
     }
 
     private List<String> getAssignedGroups() {
         List<String> groups = new ArrayList<String>();
         Node mainNode = getRelatedNode(item);
         try {
             if (mainNode.hasNode("groups")) {
                 Node groupsNode = mainNode.getNode("groups");
                 if (groupsNode == null) {
                     // shouldn't happen, just in case
                     return groups;
                 }
                 PropertyIterator pi = groupsNode.getProperties();
                 while (pi.hasNext()) {
                     Property p = pi.nextProperty();
                     if (!p.getName().startsWith(NodeTypes.JCR_PREFIX)) {
                         // do not add system properties
                         groups.add(p.getString());
                     }
                 }
             }
         } catch (RepositoryException re) {
             log.error("Cannot read assigned groups of the node ["+mainNode+"].", re);
         }
         return groups;
     }
 
     @Override
     public com.vaadin.data.Property getOrCreateProperty() {
         DefaultProperty prop = new DefaultProperty("groups", getAssignedGroups());
         item.addItemProperty("groups", prop);
         return prop;
     }
 
 }