content: /*
   * Solo - A small and beautiful blogging system written in Java.
   * Copyright (c) 2010-present, b3log.org
   *
   * Solo is licensed under Mulan PSL v2.
   * You can use this software according to the terms and conditions of the Mulan PSL v2.
   * You may obtain a copy of Mulan PSL v2 at:
   *         http://license.coscl.org.cn/MulanPSL2
   * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
   * See the Mulan PSL v2 for more details.
   */
  package org.b3log.solo.service;
  
  import org.apache.logging.log4j.Level;
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.b3log.latke.Keys;
  import org.b3log.latke.ioc.Inject;
  import org.b3log.latke.repository.Query;
  import org.b3log.latke.repository.RepositoryException;
  import org.b3log.latke.service.ServiceException;
  import org.b3log.latke.service.annotation.Service;
  import org.b3log.solo.model.Tag;
  import org.b3log.solo.repository.TagArticleRepository;
  import org.b3log.solo.repository.TagRepository;
  import org.json.JSONObject;
  
  import java.util.List;
  
  /**
   * Tag query service.
   *
   * @author <a href="http://88250.b3log.org">Liang Ding</a>
   * @version 1.2.0.0, Mar 31, 2020
   * @since 0.4.0
   */
  @Service
  public class TagQueryService {
  
      /**
       * Logger.
       */
      private static final Logger LOGGER = LogManager.getLogger(TagQueryService.class);
  
      /**
       * Tag repository.
       */
      @Inject
      private TagRepository tagRepository;
  
      /**
       * Tag-Article repository.
       */
      @Inject
      private TagArticleRepository tagArticleRepository;
  
      /**
       * Gets article count of a tag specified by the given tag id.
       *
       * @param tagId the given tag id
       * @return article count, returns {@code -1} if occurred an exception
       */
      public int getArticleCount(final String tagId) {
          return tagArticleRepository.getArticleCount(tagId);
      }
  
      /**
       * Gets a tag by the specified tag title.
       *
       * @param tagTitle the specified tag title
       * @return for example,      <pre>
       * {
       *     "tag": {
       *         "oId": "",
       *         "tagTitle": "",
       *         "tagPublishedRefCount": int
       *     }
       * }
       * </pre>, returns {@code null} if not found
       * @throws ServiceException service exception
       */
      public JSONObject getTagByTitle(final String tagTitle) throws ServiceException {
          try {
              final JSONObject tag = tagRepository.getByTitle(tagTitle);
              if (null == tag) {
                  return null;
              }
  
              final JSONObject ret = new JSONObject();
              ret.put(Tag.TAG, tag);
  
              return ret;
          } catch (final RepositoryException e) {
              LOGGER.log(Level.ERROR, "Gets an article failed", e);
              throw new ServiceException(e);
          }
      }
  
      /**
       * Gets the count of tags.
       *
       * @return count of tags
       */
      public long getTagCount() {
          try {
              return tagRepository.count();
          } catch (final RepositoryException e) {
              LOGGER.log(Level.ERROR, "Gets tags failed", e);
  
              return 0;
          }
      }
  
      /**
       * Gets all tags.
       *
       * @return for example,      <pre>
       * [
       *     {"tagTitle": "", ....},
       *     ....
       * ]
       * </pre>, returns an empty list if not found
       * @throws ServiceException service exception
       */
      public List<JSONObject> getTags() throws ServiceException {
          try {
              final Query query = new Query().setPageCount(1);
              final List<JSONObject> ret = tagRepository.getList(query);
              for (final JSONObject tag : ret) {
                  final String tagId = tag.optString(Keys.OBJECT_ID);
                  final int articleCount = tagArticleRepository.getPublishedArticleCount(tagId);
                  tag.put(Tag.TAG_T_PUBLISHED_REFERENCE_COUNT, articleCount);
              }
  
              return ret;
          } catch (final RepositoryException e) {
              LOGGER.log(Level.ERROR, "Gets tags failed", e);
  
              throw new ServiceException(e);
          }
      }
  
      /**
       * Gets tags of the published articles.
       *
       * @return tags list
       * @throws ServiceException service exception
       */
      public List<JSONObject> getTagsOfPublishedArticles() throws ServiceException {
          final List<JSONObject> ret = getTags();
          ret.removeIf(tag -> tagArticleRepository.getPublishedArticleCount(tag.optString(Keys.OBJECT_ID)) < 1);
  
          return ret;
      }
  }
  