/**
    * This file Copyright (c) 2018 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.admincentral.apps.messages;
  
  import info.magnolia.context.MgnlContext;
  import info.magnolia.ui.api.message.Message;
  import info.magnolia.ui.api.message.MessageType;
  import info.magnolia.ui.contentapp.DataFilter;
  import info.magnolia.ui.framework.message.MessagesManager;
  
  import java.util.List;
  import java.util.Map;
  import java.util.stream.Collectors;
  import java.util.stream.Stream;
  
  import javax.inject.Inject;
  
  import org.apache.commons.collections4.CollectionUtils;
  import org.apache.commons.lang3.StringUtils;
  
  import com.google.common.collect.Lists;
  import com.vaadin.data.provider.AbstractDataProvider;
  import com.vaadin.data.provider.Query;
  import com.vaadin.data.provider.QuerySortOrder;
  import com.vaadin.shared.data.sort.SortDirection;
  
  /**
   * Provide consolidated APIs to work on {@link Message}.
   */
  public class MessageDataProvider extends AbstractDataProvider<Message, DataFilter> {
  
      private final MessagesManager messagesManager;
      private MessageDataSourceDefinition definition;
  
      @Inject
      public MessageDataProvider(MessagesManager messagesManager, MessageDataSourceDefinition definition) {
          this.messagesManager = messagesManager;
          this.definition = definition;
      }
  
      @Override
      public boolean isInMemory() {
          return true;
      }
  
      @Override
      public int size(Query<Message, DataFilter> query) {
          Long size = messagesManager.getMessagesAmount(MgnlContext.getUser().getName(), getFilteredMessageTypes());
          return size.intValue();
      }
  
      @Override
      public Stream<Message> fetch(Query<Message, DataFilter> query) {
  
          final Map<String, Boolean> sortCriteria = query.getSortOrders().stream()
                  .collect(Collectors.toMap(QuerySortOrder::getSorted, so -> so.getDirection() == SortDirection.ASCENDING ? Boolean.TRUE : Boolean.FALSE, (a, b) -> b));
  
          // by default, sort result set by timestamp
          if (sortCriteria.isEmpty()) {
              sortCriteria.put("timestamp", true);
          }
          int limit = query.getLimit();
          int offset = query.getOffset();
  
          if (query.getFilter().isPresent() && query.getFilter().get().getPropertyFilters().containsKey("id")) {
              String id = query.getFilter().get().getPropertyFilters().get("id").toString();
              if (StringUtils.isNotEmpty(id)) {
                  return Stream.of(messagesManager.getMessageById(MgnlContext.getUser().getName(), id));
             }
         }
         final List<Message> messageBatch = messagesManager.getMessageBatch(MgnlContext.getUser().getName(), getFilteredMessageTypes(), sortCriteria, limit, offset);
         return messageBatch.stream();
     }
 
     protected List<MessageType> getFilteredMessageTypes() {
         final List<MessageType> messageTypes = CollectionUtils.isEmpty(definition.getMessageTypes()) ? Lists.newArrayList(MessageType.values()) : definition.getMessageTypes().stream().map(type -> MessageType.valueOf(type)).collect(Collectors.toList());
         return messageTypes;
     }
 }