content: /*
   * Symphony - A modern community (forum/BBS/SNS/blog) platform written in Java.
   * Copyright (C) 2012-present, b3log.org
   *
   * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU Affero General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU Affero General Public License for more details.
   *
   * You should have received a copy of the GNU Affero General Public License
   * along with this program.  If not, see <https://www.gnu.org/licenses/>.
   */
  package org.b3log.symphony.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.RepositoryException;
  import org.b3log.latke.repository.annotation.Transactional;
  import org.b3log.latke.service.annotation.Service;
  import org.b3log.symphony.model.Article;
  import org.b3log.symphony.model.Comment;
  import org.b3log.symphony.model.Liveness;
  import org.b3log.symphony.model.Vote;
  import org.b3log.symphony.repository.ArticleRepository;
  import org.b3log.symphony.repository.CommentRepository;
  import org.b3log.symphony.repository.TagArticleRepository;
  import org.b3log.symphony.repository.VoteRepository;
  import org.json.JSONObject;
  
  import java.util.List;
  
  /**
   * Vote management service.
   *
   * @author <a href="http://88250.b3log.org">Liang Ding</a>
   * @version 1.1.1.1, Jun 6, 2019
   * @since 1.3.0
   */
  @Service
  public class VoteMgmtService {
  
      /**
       * Logger.
       */
      private static final Logger LOGGER = LogManager.getLogger(VoteMgmtService.class);
  
      /**
       * Vote repository.
       */
      @Inject
      private VoteRepository voteRepository;
  
      /**
       * Article repository.
       */
      @Inject
      private ArticleRepository articleRepository;
  
      /**
       * Tag-Article repository.
       */
      @Inject
      private TagArticleRepository tagArticleRepository;
  
      /**
       * Comment repository.
       */
      @Inject
      private CommentRepository commentRepository;
  
      /**
       * Liveness management service.
       */
      @Inject
      private LivenessMgmtService livenessMgmtService;
  
      /**
       * Gets Reddit article score.
       *
       * @param ups   the specified vote up count
       * @param downs the specified vote down count
       * @param t     time (epoch seconds)
       * @return reddit score
       */
      private static double redditArticleScore(final int ups, final int downs, final long t) {
          final int x = ups - downs;
          final double z = Math.max(Math.abs(x), 1);
          int y = 0;
          if (x > 0) {
              y = 1;
          } else if (x < 0) {
              y = -1;
          }
  
          return Math.log10(z) + y * (t - 1353745196) / 45000;
      }
  
      private static double redditCommentScore(final int ups, final int downs) {
          final int n = ups + downs;
          if (0 == n) {
              return 0;
          }
  
          final double z = 1.281551565545; // 1.0: 85%, 1.6: 95%, 1.281551565545: 80%
          final double p = (double) ups / n;
  
          return (p + z * z / (2 * n) - z * Math.sqrt((p * (1 - p) + z * z / (4 * n)) / n)) / (1 + z * z / n);
      }
  
      /**
       * Cancels the vote.
       *
       * @param userId   the specified user id
       * @param dataId   the specified data id
       * @param dataType the specified data type
       */
      @Transactional
      public void voteCancel(final String userId, final String dataId, final int dataType) {
          try {
              final int oldType = voteRepository.removeIfExists(userId, dataId, dataType);
  
              if (Vote.DATA_TYPE_C_ARTICLE == dataType) {
                  final JSONObject article = articleRepository.get(dataId);
                  if (null == article) {
                      LOGGER.log(Level.ERROR, "Not found article [id={}] to vote cancel", dataId);
                      return;
                  }
  
                  if (Vote.TYPE_C_UP == oldType) {
                      article.put(Article.ARTICLE_GOOD_CNT, article.optInt(Article.ARTICLE_GOOD_CNT) - 1);
                  } else if (Vote.TYPE_C_DOWN == oldType) {
                      article.put(Article.ARTICLE_BAD_CNT, article.optInt(Article.ARTICLE_BAD_CNT) - 1);
                  }
  
                  final int ups = article.optInt(Article.ARTICLE_GOOD_CNT);
                  final int downs = article.optInt(Article.ARTICLE_BAD_CNT);
                  final long t = article.optLong(Keys.OBJECT_ID) / 1000;
  
                  final double redditScore = redditArticleScore(ups, downs, t);
                  article.put(Article.REDDIT_SCORE, redditScore);
  
                  updateTagArticleScore(article);
  
                  articleRepository.update(dataId, article, Article.ARTICLE_GOOD_CNT, Article.ARTICLE_BAD_CNT, Article.REDDIT_SCORE);
              } else if (Vote.DATA_TYPE_C_COMMENT == dataType) {
                  final JSONObject comment = commentRepository.get(dataId);
                  if (null == comment) {
                      LOGGER.log(Level.ERROR, "Not found comment [id={}] to vote cancel", dataId);
                      return;
                  }
  
                  if (Vote.TYPE_C_UP == oldType) {
                      comment.put(Comment.COMMENT_GOOD_CNT, comment.optInt(Comment.COMMENT_GOOD_CNT) - 1);
                  } else if (Vote.TYPE_C_DOWN == oldType) {
                      comment.put(Comment.COMMENT_BAD_CNT, comment.optInt(Comment.COMMENT_BAD_CNT) - 1);
                  }
  
                  final int ups = comment.optInt(Comment.COMMENT_GOOD_CNT);
                  final int downs = comment.optInt(Comment.COMMENT_BAD_CNT);
  
                  final double redditScore = redditCommentScore(ups, downs);
                  comment.put(Comment.COMMENT_SCORE, redditScore);
  
                  commentRepository.update(dataId, comment);
              } else {
                  LOGGER.warn("Wrong data type [" + dataType + "]");
              }
          } catch (final RepositoryException e) {
              LOGGER.log(Level.ERROR, e.getMessage());
          }
      }
  
      /**
       * The specified user vote up the specified article/comment.
       *
       * @param userId   the specified user id
       * @param dataId   the specified article/comment id
       * @param dataType the specified data type
       */
      @Transactional
      public void voteUp(final String userId, final String dataId, final int dataType) {
          try {
              up(userId, dataId, dataType);
          } catch (final RepositoryException e) {
              final String msg = "User[id=" + userId + "] vote up an [" + dataType + "][id=" + dataId + "] failed";
              LOGGER.log(Level.ERROR, msg, e);
          }
  
          livenessMgmtService.incLiveness(userId, Liveness.LIVENESS_VOTE);
      }
  
      /**
       * The specified user vote down the specified article、comment.
       *
       * @param userId the specified user id
       * @param dataId the specified article id
       */
      @Transactional
      public void voteDown(final String userId, final String dataId, final int dataType) {
          try {
              down(userId, dataId, dataType);
          } catch (final RepositoryException e) {
              final String msg = "User[id=" + userId + "] vote down an [" + dataType + "][id=" + dataId + "] failed";
              LOGGER.log(Level.ERROR, msg, e);
          }
  
          livenessMgmtService.incLiveness(userId, Liveness.LIVENESS_VOTE);
      }
  
      /**
       * The specified user vote up the specified data entity with the specified data type.
       *
       * @param userId   the specified user id
       * @param dataId   the specified data entity id
       * @param dataType the specified data type
       * @throws RepositoryException repository exception
       */
      private void up(final String userId, final String dataId, final int dataType) throws RepositoryException {
          final int oldType = voteRepository.removeIfExists(userId, dataId, dataType);
  
          if (Vote.DATA_TYPE_C_ARTICLE == dataType) {
              final JSONObject article = articleRepository.get(dataId);
              if (null == article) {
                  LOGGER.log(Level.ERROR, "Not found article [id={}] to vote up", dataId);
                  return;
              }
  
              if (-1 == oldType) {
                  article.put(Article.ARTICLE_GOOD_CNT, article.optInt(Article.ARTICLE_GOOD_CNT) + 1);
              } else if (Vote.TYPE_C_DOWN == oldType) {
                  article.put(Article.ARTICLE_BAD_CNT, article.optInt(Article.ARTICLE_BAD_CNT) - 1);
                  article.put(Article.ARTICLE_GOOD_CNT, article.optInt(Article.ARTICLE_GOOD_CNT) + 1);
              }
  
              final int ups = article.optInt(Article.ARTICLE_GOOD_CNT);
              final int downs = article.optInt(Article.ARTICLE_BAD_CNT);
              final long t = article.optLong(Keys.OBJECT_ID) / 1000;
  
              final double redditScore = redditArticleScore(ups, downs, t);
              article.put(Article.REDDIT_SCORE, redditScore);
  
              updateTagArticleScore(article);
  
              articleRepository.update(dataId, article, Article.ARTICLE_GOOD_CNT, Article.ARTICLE_BAD_CNT, Article.REDDIT_SCORE);
          } else if (Vote.DATA_TYPE_C_COMMENT == dataType) {
              final JSONObject comment = commentRepository.get(dataId);
              if (null == comment) {
                  LOGGER.log(Level.ERROR, "Not found comment [id={}] to vote up", dataId);
                  return;
              }
  
              if (-1 == oldType) {
                  comment.put(Comment.COMMENT_GOOD_CNT, comment.optInt(Comment.COMMENT_GOOD_CNT) + 1);
              } else if (Vote.TYPE_C_DOWN == oldType) {
                  comment.put(Comment.COMMENT_BAD_CNT, comment.optInt(Comment.COMMENT_BAD_CNT) - 1);
                  comment.put(Comment.COMMENT_GOOD_CNT, comment.optInt(Comment.COMMENT_GOOD_CNT) + 1);
              }
  
              final int ups = comment.optInt(Comment.COMMENT_GOOD_CNT);
              final int downs = comment.optInt(Comment.COMMENT_BAD_CNT);
  
              final double redditScore = redditCommentScore(ups, downs);
              comment.put(Comment.COMMENT_SCORE, redditScore);
  
              commentRepository.update(dataId, comment);
          } else {
              LOGGER.warn("Wrong data type [" + dataType + "]");
          }
  
          final JSONObject vote = new JSONObject();
          vote.put(Vote.USER_ID, userId);
          vote.put(Vote.DATA_ID, dataId);
          vote.put(Vote.TYPE, Vote.TYPE_C_UP);
          vote.put(Vote.DATA_TYPE, dataType);
  
          voteRepository.add(vote);
      }
  
      /**
       * The specified user vote down the specified data entity with the specified data type.
       *
       * @param userId   the specified user id
       * @param dataId   the specified data entity id
       * @param dataType the specified data type
       * @throws RepositoryException repository exception
       */
      private void down(final String userId, final String dataId, final int dataType) throws RepositoryException {
          final int oldType = voteRepository.removeIfExists(userId, dataId, dataType);
  
          if (Vote.DATA_TYPE_C_ARTICLE == dataType) {
              final JSONObject article = articleRepository.get(dataId);
              if (null == article) {
                  LOGGER.log(Level.ERROR, "Not found article [id={}] to vote down", dataId);
                  return;
              }
  
              if (-1 == oldType) {
                  article.put(Article.ARTICLE_BAD_CNT, article.optInt(Article.ARTICLE_BAD_CNT) + 1);
              } else if (Vote.TYPE_C_UP == oldType) {
                  article.put(Article.ARTICLE_GOOD_CNT, article.optInt(Article.ARTICLE_GOOD_CNT) - 1);
                  article.put(Article.ARTICLE_BAD_CNT, article.optInt(Article.ARTICLE_BAD_CNT) + 1);
              }
  
              final int ups = article.optInt(Article.ARTICLE_GOOD_CNT);
              final int downs = article.optInt(Article.ARTICLE_BAD_CNT);
              final long t = article.optLong(Keys.OBJECT_ID) / 1000;
  
              final double redditScore = redditArticleScore(ups, downs, t);
              article.put(Article.REDDIT_SCORE, redditScore);
  
              updateTagArticleScore(article);
  
              articleRepository.update(dataId, article, Article.ARTICLE_GOOD_CNT, Article.ARTICLE_BAD_CNT, Article.REDDIT_SCORE);
          } else if (Vote.DATA_TYPE_C_COMMENT == dataType) {
              final JSONObject comment = commentRepository.get(dataId);
              if (null == comment) {
                  LOGGER.log(Level.ERROR, "Not found comment [id={}] to vote up", dataId);
                  return;
              }
  
              if (-1 == oldType) {
                  comment.put(Comment.COMMENT_BAD_CNT, comment.optInt(Comment.COMMENT_BAD_CNT) + 1);
              } else if (Vote.TYPE_C_UP == oldType) {
                  comment.put(Comment.COMMENT_GOOD_CNT, comment.optInt(Comment.COMMENT_GOOD_CNT) - 1);
                  comment.put(Comment.COMMENT_BAD_CNT, comment.optInt(Comment.COMMENT_BAD_CNT) + 1);
              }
  
              final int ups = comment.optInt(Comment.COMMENT_GOOD_CNT);
              final int downs = comment.optInt(Comment.COMMENT_BAD_CNT);
  
              final double redditScore = redditCommentScore(ups, downs);
              comment.put(Comment.COMMENT_SCORE, redditScore);
  
              commentRepository.update(dataId, comment);
          } else {
              LOGGER.warn("Wrong data type [" + dataType + "]");
          }
  
          final JSONObject vote = new JSONObject();
          vote.put(Vote.USER_ID, userId);
          vote.put(Vote.DATA_ID, dataId);
          vote.put(Vote.TYPE, Vote.TYPE_C_DOWN);
          vote.put(Vote.DATA_TYPE, dataType);
  
          voteRepository.add(vote);
      }
  
      private void updateTagArticleScore(final JSONObject article) throws RepositoryException {
          final List<JSONObject> tagArticleRels = tagArticleRepository.getByArticleId(article.optString(Keys.OBJECT_ID));
          for (final JSONObject tagArticleRel : tagArticleRels) {
              tagArticleRel.put(Article.REDDIT_SCORE, article.optDouble(Article.REDDIT_SCORE, 0D));
  
              tagArticleRepository.update(tagArticleRel.optString(Keys.OBJECT_ID), tagArticleRel);
          }
      }
  }
  