/*
 * Copyright (C) 2000 - 2024 Silverpeas
 *
 * 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.
 *
 * As a special exception to the terms and conditions of version 3.0 of
 * the GPL, you may redistribute this Program in connection with Free/Libre
 * Open Source Software ("FLOSS") applications as described in Silverpeas's
 * FLOSS exception. You should have received a copy of the text describing
 * the FLOSS exception, and it is also available here:
 * "https://www.silverpeas.org/legal/floss_exception.html"
 *
 * 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.silverpeas.components.blog.service;

import org.silverpeas.components.blog.BlogContentManager;
import org.silverpeas.components.blog.dao.PostDAO;
import org.silverpeas.components.blog.model.Archive;
import org.silverpeas.components.blog.model.BlogRuntimeException;
import org.silverpeas.components.blog.model.Category;
import org.silverpeas.components.blog.model.PostDetail;
import org.silverpeas.components.blog.notification.BlogUserSubscriptionNotification;
import org.silverpeas.core.ResourceReference;
import org.silverpeas.core.annotation.Service;
import org.silverpeas.core.comment.model.Comment;
import org.silverpeas.core.comment.service.CommentService;
import org.silverpeas.core.contribution.content.wysiwyg.service.WysiwygController;
import org.silverpeas.core.contribution.contentcontainer.content.ContentManagerException;
import org.silverpeas.core.contribution.model.ContributionIdentifier;
import org.silverpeas.core.contribution.publication.model.Location;
import org.silverpeas.core.contribution.publication.model.PublicationDetail;
import org.silverpeas.core.contribution.publication.model.PublicationPK;
import org.silverpeas.core.contribution.publication.service.PublicationService;
import org.silverpeas.core.html.PermalinkRegistry;
import org.silverpeas.core.index.search.SearchEngineProvider;
import org.silverpeas.core.index.search.model.MatchingIndexEntry;
import org.silverpeas.core.index.search.model.QueryDescription;
import org.silverpeas.core.initialization.Initialization;
import org.silverpeas.core.node.model.NodeDetail;
import org.silverpeas.core.node.model.NodeOrderComparator;
import org.silverpeas.core.node.model.NodePK;
import org.silverpeas.core.node.service.NodeService;
import org.silverpeas.core.notification.user.builder.helper.UserNotificationHelper;
import org.silverpeas.core.pdc.pdc.model.ClassifyPosition;
import org.silverpeas.core.pdc.pdc.model.PdcClassification;
import org.silverpeas.core.pdc.pdc.model.PdcException;
import org.silverpeas.core.pdc.pdc.service.PdcManager;
import org.silverpeas.core.pdc.subscription.service.PdcSubscriptionManager;
import org.silverpeas.core.persistence.jdbc.DBUtil;
import org.silverpeas.core.subscription.SubscriptionService;
import org.silverpeas.core.subscription.SubscriptionServiceProvider;
import org.silverpeas.core.subscription.service.ComponentSubscription;
import org.silverpeas.core.util.DateUtil;
import org.silverpeas.kernel.bundle.LocalizationBundle;
import org.silverpeas.kernel.bundle.ResourceLocator;
import org.silverpeas.kernel.bundle.SettingBundle;
import org.silverpeas.kernel.util.StringUtil;
import org.silverpeas.kernel.logging.SilverLogger;

import javax.annotation.Nonnull;
import javax.inject.Inject;
import javax.inject.Named;
import javax.transaction.Transactional;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.*;
import java.util.stream.Stream;

import static java.util.stream.Collectors.*;
import static org.silverpeas.core.SilverpeasExceptionMessages.*;
import static org.silverpeas.core.contribution.publication.dao.PublicationCriteria.onComponentInstanceIds;

/**
 * Default implementation of the services provided by the Blog component. It is managed by the
 * underlying IoC container. At initialization by the IoC container, it registers itself among
 * different services for which it is interested.
 */
@Service
@Named("blogService")
public class DefaultBlogService implements BlogService, Initialization {

  private static final String MESSAGES_PATH = "org.silverpeas.blog.multilang.blogBundle";
  private static final String SETTINGS_PATH = "org.silverpeas.blog.settings.blogSettings";
  private static final SettingBundle settings = ResourceLocator.getSettingBundle(SETTINGS_PATH);
  private static final String POST = "post";
  private static final String USELESS = "useless";
  @Inject
  private CommentService commentService;
  @Inject
  private PdcManager pdcManager;
  @Inject
  private PdcSubscriptionManager pdcSubscriptionManager;
  @Inject
  private BlogContentManager blogContentManager;
  @Inject
  private NodeService nodeService;
  @Inject
  private PublicationService publicationService;

  @Override
  public void init() {
    PermalinkRegistry.get()
        .addUrlPart("Post");
  }

  @Override
  public Optional<PostDetail> getContributionById(ContributionIdentifier contributionId) {
    PublicationDetail publication = publicationService.getDetail(
        new PublicationPK(contributionId.getLocalId(), contributionId.getComponentInstanceId()));
    return publication == null ?
        Optional.empty() :
        toPosts(publication.getInstanceId(), List.of(publication)).stream().findFirst();
  }

  @Override
  public SettingBundle getComponentSettings() {
    return settings;
  }

  @Override
  public LocalizationBundle getComponentMessages(String language) {
    return ResourceLocator.getLocalizationBundle(MESSAGES_PATH, language);
  }

  @Override
  public boolean isRelatedTo(final String instanceId) {
    return instanceId.startsWith("blog");
  }

  private Map<String, Date> getEventDateIndexedByPost(Collection<String> pubIds) {
    try {
      return PostDAO.getEventDateIndexedByPost(pubIds);
    } catch (SQLException e) {
      throw new BlogRuntimeException(failureOnGetting(POST, pubIds), e);
    }
  }

  @Transactional
  @Override
  public String createPost(PostDetail post) {
    return createPost(post, null);
  }

  @Transactional
  @Override
  public String createPost(final PostDetail post, PdcClassification classification) {
    try (Connection con = openConnection()) {
      // Create publication
      PublicationDetail pub = post.getPublication();
      pub.setStatus(PublicationDetail.DRAFT_STATUS);
      PublicationPK pk = publicationService.createPublication(pub);

      // Create post
      PostDAO.create(con, pk.getId(), post.getDateEvent(), pk.getInstanceId());
      if (StringUtil.isDefined(post.getCategoryId())) {
        setCategory(pk, post.getCategoryId());
      }

      // Create empty wysiwyg content
      WysiwygController.createUnindexedFileAndAttachment("", new ResourceReference(pk),
          pub.getCreatorId(), pub.getLanguage());

      // Create silver content
      createSilverContent(con, pub, pub.getCreatorId());

      // classify the publication on the PdC if its classification is defined
      if (classification != null) {
        classification.classifyContent(pub);
      }

      return pk.getId();
    } catch (Exception e) {
      throw new BlogRuntimeException(failureOnAdding(POST, post.getId()), e);
    }
  }

  @Override
  public void sendSubscriptionsNotification(final NodePK fatherPK, final PostDetail post,
      final Comment comment, final String type, final String senderId) {
    UserNotificationHelper.buildAndSend(
        new BlogUserSubscriptionNotification(post, comment, type, senderId));
    // send notification if PDC subscription
    try {
      final PublicationPK pubPK = post.getPublication().getPK();
      int silverObjectId = getSilverObjectId(pubPK);
      List<ClassifyPosition> positions = pdcManager.getPositions(silverObjectId, pubPK
          .getInstanceId());
      if (positions != null) {
        for (ClassifyPosition position : positions) {
          pdcSubscriptionManager.checkSubscriptions(position.getValues(), pubPK
              .getInstanceId(), silverObjectId);
        }
      }
    } catch (PdcException e) {
      SilverLogger.getLogger(this)
          .error("PdC subscriber notification failure", e);
    }
  }

  @Transactional
  @Override
  public void updatePost(PostDetail post, final PdcClassification classification) {
    try (Connection con = openConnection()) {
      PublicationPK pubPk = post.getPublication()
          .getPK();
      PublicationDetail pub = post.getPublication();

      // Remove last category
      publicationService.removeAllFathers(pubPk);

      // Save the publication
      publicationService.setDetail(pub);

      // Add the new category
      if (StringUtil.isDefined(post.getCategoryId())) {
        setCategory(pubPk, post.getCategoryId());
      }

      // Update event date
      PostDAO.update(con, pubPk.getId(), post.getDateEvent());

      // Save wysiwyg content and do not index it (cause it is already indexed as publication 
      // content)
      WysiwygController.updateFileAndAttachment(post.getContent(), pub.getInstanceId(),
          pubPk.getId(), pub.getUpdaterId(), pub.getLanguage(), false);

      // classify the publication on the PdC if any
      if (classification != null) {
        classification.classifyContentOrClearClassificationIfEmpty(pub, false);
      }

      // Send notification if subscription
      if (pub.isValid()) {
        sendSubscriptionsNotification(new NodePK("0", pub.getPK()
            .getSpaceId(), pub.getPK()
            .getInstanceId()), post, null, "update", pub.getUpdaterId());
      }

    } catch (SQLException e) {
      throw new BlogRuntimeException(failureOnUpdate(POST, post.getId()), e);
    }
  }

  private void setCategory(PublicationPK pk, String categoryId) {
    NodePK nodePK = new NodePK(categoryId, pk.getInstanceId());
    publicationService.addFather(pk, nodePK);
  }

  @Transactional
  @Override
  public void deletePost(String instanceId, String postId) {

    try (Connection con = openConnection()) {
      PublicationPK pubPK = new PublicationPK(postId, instanceId);
      // Delete link with categorie
      publicationService.removeAllFathers(pubPK);
      // Delete date event
      PostDAO.delete(con, pubPK.getId());
      // Delete comments
      ResourceReference resourceReference = new ResourceReference(postId, instanceId);
      getCommentService().deleteAllCommentsOnResource(PostDetail.getResourceType(),
          resourceReference);
      // Delete wysiwyg content
      WysiwygController.deleteFileAndAttachment(instanceId, postId);
      // Delete publication
      publicationService.deletePublication(pubPK);
      // Delete silverContent
      blogContentManager.deleteSilverContent(con, pubPK);
    } catch (Exception e) {
      throw new BlogRuntimeException(failureOnDeleting(POST, postId), e);
    }
  }

  private Connection openConnection() {
    Connection con;
    try {
      con = DBUtil.openConnection();
    } catch (SQLException e) {
      // traitement des exceptions
      throw new BlogRuntimeException(failureOnOpeningConnectionTo("datasource"), e);
    }
    return con;
  }

  @Nonnull
  private List<PostDetail> toPosts(final String instanceId,
    final Collection<PublicationDetail> publications) {
    if (!publications.isEmpty()) {
      final Map<Location, Category> categoryByAllNodePKs = nodeService.getAllNodes(
              new NodePK(null, instanceId))
          .stream()
          .collect(toMap(n -> new Location(n.getId(), instanceId), Category::new));
      final Collection<String> pubIds = publications.stream()
          .map(PublicationDetail::getPK)
          .map(PublicationPK::getId)
          .collect(toSet());
      final Map<String, Category> allLocationsByPublicationIds =
          publicationService.getAllLocationsByPublicationIds(pubIds)
          .entrySet()
          .stream()
          .collect(toMap(Map.Entry::getKey, e -> categoryByAllNodePKs.get(e.getValue().get(0))));
      final Map<String, Date> eventDateByPost = getEventDateIndexedByPost(pubIds);
      final Map<String, Integer> commentsByPubIds =
          getCommentService().getCommentCountIndexedByResource(
              PostDetail.getResourceType(), instanceId)
          .entrySet()
          .stream()
          .collect(toMap(e -> e.getKey().getLocalId(), Map.Entry::getValue));
      final Date defaultDate = new Date();
      return publications.stream().map(p -> {
        final String pubId = p.getPK().getId();
        final Category cat = allLocationsByPublicationIds.get(pubId);
        final Date dateEvent = eventDateByPost.getOrDefault(pubId, defaultDate);
        final int nbComments = commentsByPubIds.getOrDefault(pubId, 0);
        final PostDetail post = new PostDetail(p, cat, nbComments, dateEvent);
        //noinspection removal
        post.setCreatorName(p.getCreator().getDisplayedName());
        return post;
      }).collect(toList());
    }
    return List.of();
  }

  @Override
  public Collection<PostDetail> getLastPosts(final String instanceId, final BlogFilters filters) {
    try (Connection con = openConnection()) {
      // search publications sorted by event date
      Collection<String> allPostIds = PostDAO.getAllPostIds(con, instanceId);
      final Stream<PublicationDetail> publications = filterPublications(
          publicationService.getByIds(allPostIds).stream(), filters);
      return toPosts(instanceId, publications.collect(toList()));
    } catch (Exception e) {
      throw new BlogRuntimeException(failureOnGetting("all posts of blog", instanceId), e);
    }
  }

  @Override
  public Collection<PostDetail> getAllPosts(String instanceId) {
    return getLastPosts(instanceId, new BlogFilters(true));
  }

  @Override
  public Collection<PostDetail> getLastValidPosts(String instanceId, BlogFilters filters) {
    try (Connection con = openConnection()) {
      // rechercher les publications classées par date d'évènement
      final Collection<String> allPostIds = PostDAO.getAllPostIds(con, instanceId);
      final Stream<PublicationDetail> publications = publicationService.getByIds(allPostIds)
          .stream()
          .filter(p -> PublicationDetail.VALID_STATUS.equals(p.getStatus()));
      return toPosts(instanceId, filterPublications(publications, filters).collect(toList()));
    } catch (Exception e) {
      throw new BlogRuntimeException(failureOnGetting("All validated posts for blog", instanceId),
          e);
    }
  }

  @Override
  public Collection<PostDetail> getPostsByCategory(String instanceId, String categoryId,
      final BlogFilters filters) {
    try (Connection con = openConnection()) {
      // looking for classified publications
      final Collection<String> allPostIds = PostDAO.getAllPostIds(con, instanceId);
      final Map<String, PublicationDetail> categoryPublications =
          publicationService.getPublicationsByCriteria(
              onComponentInstanceIds(instanceId).onNodes(categoryId))
          .stream()
          .collect(toMap(PublicationDetail::getId, p -> p));
      final Stream<PublicationDetail> publications = allPostIds.stream()
          .map(categoryPublications::get)
          .filter(Objects::nonNull);
      return toPosts(instanceId, filterPublications(publications, filters).collect(toList()));
    } catch (Exception e) {
      throw new BlogRuntimeException(failureOnGetting("all posts in category", categoryId), e);
    }
  }

  @Override
  public Collection<PostDetail> getPostsByEventDate(String instanceId, String date,
      final BlogFilters filters) {
    return getPostsByArchive(instanceId, date, date, filters);
  }

  @Override
  public Collection<PostDetail> getPostsByArchive(String instanceId, String beginDate, String endDate,
      final BlogFilters filters) {
    try (Connection con = openConnection()) {
      // searching publications sorted by event date
      final Collection<String> postIds = PostDAO.getPostInRange(con, instanceId, beginDate,
          endDate);
      final List<PublicationDetail> publications = publicationService.getByIds(postIds);
      return toPosts(instanceId,
          filterPublications(publications.stream(), filters).collect(toList()));
    } catch (Exception e) {
      throw new BlogRuntimeException(
          failureOnGetting("all posts archived between", beginDate + " and " + endDate), e);
    }
  }

  @Override
  public Collection<PostDetail> getResultSearch(String instanceId, String word, String userId, final BlogFilters filters) {
    QueryDescription query = new QueryDescription(word);
    query.setSearchingUser(userId);
    query.addComponent(instanceId);

    try (Connection con = openConnection()) {
      final Set<String> searchResult = SearchEngineProvider.getSearchEngine()
          .search(query)
          .getEntries()
          .stream()
          .map(MatchingIndexEntry::getObjectId)
          .collect(toSet());

      // création des billets à partir des résultats
      // rechercher la liste des posts trié par date
      final Collection<String> searchedPostIds = PostDAO.getAllPostIds(con, instanceId)
          .stream()
          .filter(searchResult::contains)
          .collect(toList());
      final List<PublicationDetail> publications = filterPublications(
          publicationService.getByIds(searchedPostIds).stream(), filters).collect(toList());
      return toPosts(instanceId, publications);
    } catch (Exception e) {
      throw new BlogRuntimeException(e);
    }
  }

  @Transactional
  @Override
  public void createCategory(Category category) {
    try {
      nodeService.createNode(category, new NodeDetail());
    } catch (Exception e) {
      throw new BlogRuntimeException(e);
    }
  }

  @Transactional
  @Override
  public void updateCategory(Category category) {
    try {
      nodeService.setDetail(category);
    } catch (Exception e) {
      throw new BlogRuntimeException(e);
    }
  }

  @Transactional
  @Override
  public void deleteCategory(String instanceId, String id) {
    try {
      NodePK nodePk = new NodePK(id, instanceId);

      // recherche des billets sur cette catégorie
      Collection<PostDetail> posts = getPostsByCategory(instanceId, id, new BlogFilters(true));
      for (PostDetail post : posts) {
        publicationService.removeFather(post.getPublication()
            .getPK(), nodePk);
      }
      // suppression de la catégorie
      nodeService.deleteNode(nodePk);
    } catch (Exception e) {
      throw new BlogRuntimeException(e);
    }
  }

  @Override
  public Category getCategory(NodePK pk) {
    return new Category(nodeService.getDetail(pk));
  }

  @Override
  public Collection<NodeDetail> getAllCategories(String instanceId) {
    NodePK nodePK = new NodePK(NodePK.ROOT_NODE_ID, instanceId);
    List<NodeDetail> result = new ArrayList<>(nodeService.getChildrenDetails(nodePK));
    result.sort(new NodeOrderComparator());
    return result;
  }

  @Override
  public Collection<Archive> getAllArchives(String instanceId) {
    try (Connection con = openConnection()) {
      final Calendar calendar = Calendar.getInstance(Locale.FRENCH);
      return PostDAO.getAllEventDates(con, instanceId)
          .stream()
          .map(d -> {
            calendar.setTime(d);
            return createArchive(calendar);
          })
          .distinct()
          .collect(toList());
    } catch (Exception e) {
      throw new BlogRuntimeException(failureOnGetting("All archives of blog", instanceId), e);
    }
  }

  private Archive createArchive(Calendar calendar) {
    Date beginDate = getMonthFirstDay(calendar);
    Date endDate = getMonthLastDay(calendar);
    // regarder s'il y a des évenements sur cette période
    Archive archive =
        new Archive(USELESS, DateUtil.date2SQLDate(beginDate), DateUtil.date2SQLDate(endDate));
    archive.setYear(java.lang.Integer.toString(calendar.get(Calendar.YEAR)));
    archive.setMonthId(java.lang.Integer.toString(calendar.get(Calendar.MONTH)));
    return archive;
  }

  @Override
  public void indexBlog(String componentId) {
    indexTopics(new NodePK(USELESS, componentId));
    indexPublications(componentId);
  }

  private void indexPublications(String componentId) {
    Collection<PublicationDetail> pubs;
    try {
      pubs = publicationService.getAllPublications(componentId);
    } catch (Exception e) {
      throw new BlogRuntimeException(
          failureOnGetting("[INDEXING] all publications in blog", componentId), e);
    }

    if (pubs != null) {
      for (PublicationDetail pub : pubs) {
        try {
          indexPublication(pub.getPK());
        } catch (Exception e) {
          throw new BlogRuntimeException(failureOnIndexing("publication", pub.getPK()
              .toString()), e);
        }
      }
    }
  }

  private void indexPublication(PublicationPK pubPK) {
    // index publication itself
    publicationService.createIndex(pubPK);
    // index external elements
    indexExternalElementsOfPublication(pubPK);
  }

  private void indexTopics(NodePK nodePK) {
    Collection<NodeDetail> nodes = nodeService.getAllNodes(nodePK);
    if (nodes != null) {
      for (NodeDetail node : nodes) {
        if (!node.getNodePK()
            .isRoot() && !node.getNodePK()
            .isTrash()) {
          nodeService.createIndex(node);
        }
      }
    }
  }

  @Override
  public boolean isSubscribed(final String userId, final String instanceId) {
    return getSubscribeService().existsSubscription(new ComponentSubscription(userId, instanceId));
  }

  private void indexExternalElementsOfPublication(PublicationPK pubPK) {
    try {
      // index comments
      getCommentService().indexAllCommentsOnPublication(PostDetail.getResourceType(),
          new ResourceReference(pubPK));
    } catch (Exception e) {
      SilverLogger.getLogger(this)
          .error("Comment index failure for publication {0}", new String[]{pubPK.toString()}, e);
    }
  }

  private Date getMonthFirstDay(Calendar calendar) {
    calendar.set(Calendar.DAY_OF_MONTH, 1);
    return calendar.getTime();
  }

  private Date getMonthLastDay(Calendar calendar) {
    int monthLastDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
    calendar.set(Calendar.DAY_OF_MONTH, monthLastDay);
    return calendar.getTime();
  }

  private void createSilverContent(Connection con, PublicationDetail pubDetail, String creatorId) {
    try {
      blogContentManager.createSilverContent(con, pubDetail, creatorId);
    } catch (ContentManagerException e) {
      throw new BlogRuntimeException(e);
    }
  }

  private void updateSilverContentVisibility(PublicationDetail pubDetail) {
    try {
      blogContentManager.updateSilverContentVisibility(pubDetail);
    } catch (Exception e) {
      throw new BlogRuntimeException(e);
    }
  }

  @Override
  public void draftOutPost(PostDetail post) {

    PublicationDetail pub = post.getPublication();
    pub.setStatus(PublicationDetail.VALID_STATUS);

    // update the publication
    publicationService.setDetail(pub);

    if (pub.getStatus()
        .equals(PublicationDetail.VALID_STATUS)) {

      // update visibility attribute on PDC
      updateSilverContentVisibility(pub);

      // send notification if instance subscription
      sendSubscriptionsNotification(new NodePK("0", pub.getPK()
          .getSpaceId(), pub.getPK()
          .getInstanceId()), post, null, "create", pub.getUpdaterId());
    }
  }

  private Stream<PublicationDetail> filterPublications(final Stream<PublicationDetail> pubs,
      final BlogFilters filters) {
    Stream<PublicationDetail> stream = pubs.filter(filters.toPredicate());
    final Optional<Integer> maxResult = filters.getMaxResult();
    if (maxResult.isPresent()) {
      stream = stream.limit(maxResult.get());
    }
    return stream;
  }

  private int createSilverContent(PublicationDetail pubDetail, String creatorId) {
    Connection con = null;
    try {
      con = openConnection();
      return blogContentManager.createSilverContent(con, pubDetail, creatorId);
    } catch (Exception e) {
      throw new BlogRuntimeException(e);
    } finally {
      DBUtil.close(con);
    }
  }


  private int getSilverObjectId(PublicationPK pubPK) {

    int silverObjectId;
    PublicationDetail pubDetail;
    try {
      silverObjectId = blogContentManager.getSilverContentId(pubPK.getId(), pubPK.getInstanceId());
      if (silverObjectId == -1) {
        pubDetail = publicationService.getDetail(pubPK);
        silverObjectId = createSilverContent(pubDetail, pubDetail.getCreatorId());
      }
    } catch (Exception e) {
      throw new BlogRuntimeException(e);
    }
    return silverObjectId;
  }

  private SubscriptionService getSubscribeService() {
    return SubscriptionServiceProvider.getSubscribeService();
  }

  /**
   * Gets a DefaultCommentService instance.
   * @return a DefaultCommentService instance.
   */
  protected CommentService getCommentService() {
    return commentService;
  }
}
