/**
    * This file Copyright (c) 2020 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.resources.app.data;
  
  import static info.magnolia.resources.app.workbench.tree.ResourcesTreePresenter.*;
  
  import info.magnolia.jcr.RuntimeRepositoryException;
  import info.magnolia.jcr.util.NodeTypes;
  import info.magnolia.resourceloader.Resource;
  import info.magnolia.resourceloader.ResourceOrigin;
  import info.magnolia.resourceloader.layered.LayeredResource;
  import info.magnolia.ui.datasource.optionlist.Option;
  import info.magnolia.ui.filter.DataFilter;
  
  import java.util.Arrays;
  import java.util.List;
  import java.util.stream.Stream;
  
  import javax.inject.Inject;
  import javax.jcr.Node;
  import javax.jcr.RepositoryException;
  
  import org.apache.commons.lang3.StringUtils;
  
  import com.vaadin.data.provider.AbstractBackEndDataProvider;
  import com.vaadin.data.provider.Query;
  
  /**
   * Flat data provider used while filtering grid.
   */
  public class ResourceFilteringDataProvider extends AbstractBackEndDataProvider<Resource, DataFilter> implements ResourceHelper {
  
      private final ResourceOrigin<?> resourceOrigin;
  
      @Inject
      public ResourceFilteringDataProvider(ResourceOrigin<?> resourceOrigin) {
          this.resourceOrigin = resourceOrigin;
      }
  
      @Override
      public Object getId(Resource item) {
          return item.getPath();
      }
  
      @Override
      protected Stream<Resource> fetchFromBackEnd(Query<Resource, DataFilter> query) {
          return resourceOrigin.find("/", resource -> query.getFilter()
                  .map(dataFilter -> applyFilter(resource, dataFilter))
                  .orElse(true))
                  .skip(query.getOffset())
                  .limit(query.getLimit());
      }
  
      private boolean applyFilter(Resource resource, DataFilter filter) {
          return filter.getPropertyFilters().entrySet().stream()
                  .filter(stringObjectEntry -> !"".equals(stringObjectEntry.getValue())) //empty text filter
                  .allMatch(stringObjectEntry -> filter(stringObjectEntry.getValue(), resource, stringObjectEntry.getKey()));
      }
  
      private boolean filter(Object filterValue, Resource resource, String propertyName) {
          if (filterValue == null) { //empty filter
              return true;
          } else if (COLUMN_ORIGIN.equals(propertyName)) {
              return filterByOrigin((ResourceOrigin<?>) filterValue, resource);
          } else if (COLUMN_TYPE.equals(propertyName)) {
              return StringUtils.contains(TIKA.detect(resource.getName()), (String) filterValue);
          } else if (COLUMN_NAME.equals(propertyName)) {
              return resource.getName().contains((String) filterValue);
         } else if (COLUMN_OVERRIDDEN.equals(propertyName)) {
             return !((Boolean) filterValue) || (resource instanceof LayeredResource && ((LayeredResource) resource).getLayers().size() > 1);
         } else if (COLUMN_STATUS.equals(propertyName)) {
             int expectedStatus = Integer.parseInt(((Option) filterValue).getValue());
             return getJcrNode(resource)
                     .map(this::getActivationStatus)
                     .map(integer -> integer == expectedStatus)
                     .orElse(false);
         }
         throw new IllegalArgumentException("Unsupported filter property: " + propertyName);
     }
 
     private boolean filterByOrigin(ResourceOrigin<?> filterValue, Resource resource) {
         List<Resource> resources = resource instanceof LayeredResource ? ((LayeredResource) resource).getLayers() : Arrays.asList(resource);
         return resources.stream()
                 .map(Resource::getOrigin)
                 .anyMatch(origin -> origin.getClass().equals(filterValue.getClass()));
     }
 
     private int getActivationStatus(Node node) {
         try {
             return NodeTypes.Activatable.getActivationStatus(node);
         } catch (RepositoryException e) {
             throw new RuntimeRepositoryException(e);
         }
     }
 
     @Override
     protected int sizeInBackEnd(Query<Resource, DataFilter> query) {
         return (int) fetchFromBackEnd(query).count();
     }
 }