/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you under the Educational
    * Community License, Version 2.0 (the "License"); you may not use this file
    * except in compliance with the License. You may obtain a copy of the License
   * at:
   *
   *   http://opensource.org/licenses/ecl2.txt
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
   * License for the specific language governing permissions and limitations under
   * the License.
   *
   */
  
  package org.opencastproject.event.comment.list;
  
  import org.opencastproject.event.comment.EventCommentException;
  import org.opencastproject.event.comment.EventCommentService;
  import org.opencastproject.list.api.ListProviderException;
  import org.opencastproject.list.api.ResourceListProvider;
  import org.opencastproject.list.api.ResourceListQuery;
  
  import org.osgi.framework.BundleContext;
  import org.osgi.service.component.annotations.Activate;
  import org.osgi.service.component.annotations.Component;
  import org.osgi.service.component.annotations.Reference;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  @Component(
      service = ResourceListProvider.class,
      property = {
          "service.description=Comments list provider",
          "opencast.service.type=org.opencastproject.list.provider.EventCommentsListProvider"
      }
  )
  public class EventCommentsListProvider implements ResourceListProvider {
  
    private static final Logger logger = LoggerFactory.getLogger(EventCommentsListProvider.class);
  
    public static final String PROVIDER_PREFIX = "comments";
  
    /** The list of filter criteria for this provider */
    public enum CommentsFilterList {
      REASON, RESOLUTION;
    };
  
    /** The resolutions */
    public enum RESOLUTION {
      ALL, UNRESOLVED, RESOLVED;
    };
  
    /** The names of the different list available through this provider */
    private final List<String> listNames = new ArrayList<String>();
  
    private EventCommentService eventCommentService;
  
    @Activate
    protected void activate(BundleContext bundleContext) {
      // Fill the list names
      for (CommentsFilterList value : CommentsFilterList.values()) {
        listNames.add(getListNameFromFilter(value));
      }
  
      logger.info("Comments list provider activated!");
    }
  
    /** OSGi callback for the event comment service. */
    @Reference
    public void setEventCommentService(EventCommentService eventCommentService) {
      this.eventCommentService = eventCommentService;
    }
  
    @Override
    public String[] getListNames() {
      return listNames.toArray(new String[listNames.size()]);
    }
  
    @Override
    public Map<String, String> getList(String listName, ResourceListQuery query)
            throws ListProviderException {
      Map<String, String> result = new HashMap<String, String>();
  
      if (CommentsFilterList.REASON.equals(listName)) {
        List<String> reasons;
        try {
          reasons = eventCommentService.getReasons();
       } catch (EventCommentException e) {
         logger.error("Error retreiving reasons from event comment service", e);
         throw new ListProviderException("Error retreiving reasons from event comment service", e);
       }
 
       for (String reason : reasons) {
         result.put(reason, reason);
       }
     } else if (CommentsFilterList.RESOLUTION.equals(listName)) {
       for (RESOLUTION value : RESOLUTION.values()) {
         result.put(value.toString(), value.toString());
       }
     } else {
       logger.warn("No comments list for list name {} found", listName);
       throw new ListProviderException("No comments list for list name " + listName + " found!");
     }
 
     return result;
   }
 
   /**
    * Returns the list name related to the given filter
    *
    * @param filter
    *          the filter from which the list name is needed
    * @return the list name related to the given filter
    */
   public static String getListNameFromFilter(CommentsFilterList filter) {
     return PROVIDER_PREFIX.toLowerCase() + "_" + filter.toString().toLowerCase();
   }
 
   @Override
   public boolean isTranslatable(String listName) {
     return true;
   }
 
   @Override
   public String getDefault() {
     return null;
   }
 }