class.ilForum.php

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<?php

declare(strict_types=1);

use ILIAS\User\Profile\Mode as PersonalProfileMode;

class ilForum
{
    private const SORT_TITLE = 1;
    private const SORT_DATE = 2;
    private const DEFAULT_PAGE_HITS = 30;

    protected static array $moderators_by_ref_id_map = [];

    private readonly ilAppEventHandler $event;
    private string $dbTable;
    private string $className = 'ilForum';
    private string $mdb2Query = '';
    private array $mdb2DataValue = [];
    private array $mdb2DataType = [];
    private string $txtQuote1 = "[quote]";
    private string $txtQuote2 = "[/quote]";
    private string $replQuote1 = '<blockquote class="ilForumQuote">';
    private string $replQuote2 = '</blockquote>';
    private int $pageHits = self::DEFAULT_PAGE_HITS;
    private int $id;
    private int $ref_id;
    private string $import_name = '';
    public ilLanguage $lng;
    public ilErrorHandling $error;
    public ilDBInterface $db;
    public ilObjUser $user;
    public ilSetting $settings;

    public function __construct()
    {
        global $DIC;

        $this->error = $DIC['ilErr'];
        $this->lng = $DIC->language();
        $this->db = $DIC->database();
        $this->user = $DIC->user();
        $this->settings = $DIC->settings();
        $this->event = $DIC->event();
    }

    public function setForumId(int $a_obj_id): void
    {
        $this->id = $a_obj_id;
    }

    public function setForumRefId(int $a_ref_id): void
    {
        $this->ref_id = $a_ref_id;
    }

    public function getForumId(): int
    {
        return $this->id;
    }

    public function getForumRefId(): int
    {
        return $this->ref_id;
    }

    public function setDbTable(string $dbTable): void
    {
        if ($dbTable === '') {
            die($this->className . '::setDbTable(): No database table given.');
        }

        $this->dbTable = $dbTable;
    }

    public function getDbTable(): string
    {
        return $this->dbTable;
    }

    public function setMDB2WhereCondition(string $query_string, array $data_type, array $data_value): bool
    {
        $this->mdb2Query = $query_string;
        $this->mdb2DataValue = $data_value;
        $this->mdb2DataType = $data_type;

        return true;
    }

    public function getMDB2Query(): string
    {
        return $this->mdb2Query ?: '';
    }

    public function getMDB2DataValue(): array
    {
        return $this->mdb2DataValue ?: [];
    }

    public function getMDB2DataType(): array
    {
        return $this->mdb2DataType ?: [];
    }

    public function setPageHits(int $pageHits): bool
    {
        if ($pageHits < 1) {
            $pageHits = 1;
        }

        $this->pageHits = $pageHits;
        return true;
    }

    public function getPageHits(): int
    {
        return $this->pageHits;
    }

    public function getOneTopic(): ForumDto
    {
        $data_type = [];
        $data_value = [];

        $query = 'SELECT * FROM frm_data WHERE ';
        if ($this->getMDB2Query() !== '' && $this->getMDB2DataType() !== [] && $this->getMDB2DataValue() !== []) {
            $query .= ' ' . $this->getMDB2Query() . ' ';
            $data_type += $this->getMDB2DataType();
            $data_value += $this->getMDB2DataValue();
        } else {
            $query .= '1 = 1';
        }

        $res = $this->db->queryF($query, $data_type, $data_value);
        $row = $this->db->fetchAssoc($res);

        if (!is_array($row) || $row === []) {
            return ForumDto::getEmptyInstance();
        }

        return ForumDto::getInstanceFromArray($row);
    }

    public function getOneThread(): ilForumTopic
    {
        $data_type = [];
        $data_value = [];

        $query = 'SELECT * FROM frm_threads WHERE ';
        if ($this->getMDB2Query() !== '' && $this->getMDB2DataType() !== [] && $this->getMDB2DataValue() !== []) {
            $query .= ' ' . $this->getMDB2Query() . ' ';
            $data_type += $this->getMDB2DataType();
            $data_value += $this->getMDB2DataValue();
        } else {
            $query .= '1 = 1';
        }

        $sql_res = $this->db->queryF($query, $data_type, $data_value);
        $result = $this->db->fetchAssoc($sql_res);
        $result['thr_subject'] = trim((string) ($result['thr_subject'] ?? ''));

        $thread_obj = new ilForumTopic();
        $thread_obj->assignData($result);

        return $thread_obj;
    }

    public function generatePost(
        int $forum_id,
        int $thread_id,
        int $author_id,
        int $display_user_id,
        string $message,
        int $parent_pos,
        bool $notify,
        string $subject = '',
        ?string $alias = null,
        string $date = '',
        bool $status = true,
        bool $send_activation_mail = false
    ): int {
        $objNewPost = new ilForumPost();
        $objNewPost->setForumId($forum_id);
        $objNewPost->setThreadId($thread_id);
        $objNewPost->setSubject($subject);
        $objNewPost->setMessage($message);
        $objNewPost->setDisplayUserId($display_user_id);
        $objNewPost->setUserAlias($alias);
        $objNewPost->setPosAuthorId($author_id);

        $frm_settings = ilForumProperties::getInstance($this->getForumId());

        $is_moderator = false;
        if ($frm_settings->getMarkModeratorPosts() && self::_isModerator($this->getForumRefId(), $author_id)) {
            $is_moderator = true;
        }
        $objNewPost->setIsAuthorModerator($is_moderator);

        if ($date === '') {
            $objNewPost->setCreateDate(date('Y-m-d H:i:s'));
        } elseif (strpos($date, '-') > 0) {
            $objNewPost->setCreateDate($date);
        }

        if ($status) {
            $objNewPost->setPostActivationDate($objNewPost->getCreateDate());
        }

        $objNewPost->setImportName($this->getImportName());
        $objNewPost->setNotification($notify);
        $objNewPost->setStatus($status);
        $objNewPost->insert();

        if ($parent_pos === 0) {
            $this->addPostTree($objNewPost->getThreadId(), $objNewPost->getId(), $objNewPost->getCreateDate());
        } else {
            $this->insertPostNode(
                $objNewPost->getId(),
                $parent_pos,
                $objNewPost->getThreadId(),
                $objNewPost->getCreateDate()
            );
        }

        $lastPost = $objNewPost->getForumId() . '#' . $objNewPost->getThreadId() . '#' . $objNewPost->getId();

        $this->db->manipulateF(
            'UPDATE frm_threads SET thr_num_posts = thr_num_posts + 1, thr_last_post = %s WHERE thr_pk = %s',
            ['text', 'integer'],
            [$lastPost, $objNewPost->getThreadId()]
        );

        $this->db->manipulateF(
            'UPDATE frm_data SET top_num_posts = top_num_posts + 1, top_last_post = %s WHERE top_pk = %s',
            ['text', 'integer'],
            [$lastPost, $objNewPost->getForumId()]
        );

        $forum_obj = ilObjectFactory::getInstanceByRefId($this->getForumRefId());
        $forum_obj->markPostRead($objNewPost->getPosAuthorId(), $objNewPost->getThreadId(), $objNewPost->getId());

        if ($status && $parent_pos > 0) {
            $news_item = new ilNewsItem();
            $news_item->setContext($forum_obj->getId(), 'frm', $objNewPost->getId(), 'pos');
            $news_item->setPriority(NEWS_NOTICE);
            $news_item->setTitle($objNewPost->getSubject());
            $news_item->setContent(ilRTE::_replaceMediaObjectImageSrc(
                $this->prepareText($objNewPost->getMessage(), 0),
                1
            ));
            if ($objNewPost->getMessage() !== strip_tags($objNewPost->getMessage())) {
                $news_item->setContentHtml(true);
            }

            $news_item->setUserId($display_user_id);
            $news_item->setVisibility(NEWS_USERS);
            $news_item->create();
        }

        return $objNewPost->getId();
    }

    public function generateThread(
        ilForumTopic $thread,
        string $message,
        bool $notify,
        bool $notify_posts,
        bool $status = true,
        bool $withFirstVisibleEntry = true
    ): int {
        if (!$thread->getCreateDate()) {
            $thread->setCreateDate(date('Y-m-d H:i:s'));
        }

        $thread->setImportName($this->getImportName());
        $thread->insert();

        if ($notify_posts) {
            $thread->enableNotification($thread->getThrAuthorId());
        }

        $this->db->manipulateF(
            'UPDATE frm_data SET top_num_threads = top_num_threads + 1 WHERE top_pk = %s',
            ['integer'],
            [$thread->getForumId()]
        );

        $rootNodeId = $this->generatePost(
            $thread->getForumId(),
            $thread->getId(),
            $thread->getThrAuthorId(),
            $thread->getDisplayUserId(),
            '',
            0,
            false,
            $thread->getSubject(),
            $thread->getUserAlias(),
            $thread->getCreateDate(),
            true,
            false
        );

        if (!$withFirstVisibleEntry) {
            return $rootNodeId;
        }

        return $this->generatePost(
            $thread->getForumId(),
            $thread->getId(),
            $thread->getThrAuthorId(),
            $thread->getDisplayUserId(),
            $message,
            $rootNodeId,
            $notify,
            $thread->getSubject(),
            $thread->getUserAlias(),
            $thread->getCreateDate(),
            $status,
            false
        );
    }

    public function moveThreads(array $thread_ids, ilObjForum $src_forum, int $target_obj_id): array
    {
        $errorMessages = [];

        if ($target_obj_id <= 0 || $src_forum->getId() <= 0) {
            return $errorMessages;
        }

        $this->setMDB2WhereCondition('top_frm_fk = %s ', ['integer'], [$src_forum->getId()]);
        $oldFrmData = $this->getOneTopic();

        $this->setMDB2WhereCondition('top_frm_fk = %s ', ['integer'], [$target_obj_id]);
        $newFrmData = $this->getOneTopic();

        if (!$oldFrmData->getTopPk() || !$newFrmData->getTopPk()) {
            return $errorMessages;
        }

        $num_moved_posts = 0;
        $num_moved_threads = 0;
        $num_visits = 0;

        foreach ($thread_ids as $id) {
            $objTmpThread = new ilForumTopic($id);

            try {
                $numPosts = $objTmpThread->movePosts(
                    $src_forum->getId(),
                    $oldFrmData->getTopPk(),
                    $target_obj_id,
                    $newFrmData->getTopPk()
                );

                if (($last_post_string = ($objTmpThread->getLastPostString() ?? '')) !== '') {
                    $last_post_string = explode('#', $last_post_string);
                    $last_post_string[0] = $newFrmData->getTopPk();
                    $last_post_string = implode('#', $last_post_string);
                    $objTmpThread->setLastPostString($last_post_string);
                }

                $num_visits += $objTmpThread->getVisits();
                $num_moved_posts += $numPosts;
                ++$num_moved_threads;

                $objTmpThread->setForumId($newFrmData->getTopPk());
                $objTmpThread->update();
            } catch (ilFileUtilsException) {
                $errorMessages[] = sprintf($this->lng->txt('frm_move_invalid_file_type'), $objTmpThread->getSubject());
                continue;
            }
        }

        if (0 === max($num_moved_threads, $num_moved_posts, $num_visits)) {
            return $errorMessages;
        }

        $this->db->setLimit(1, 0);
        $res = $this->db->queryF(
            'SELECT pos_thr_fk, pos_pk FROM frm_posts WHERE pos_top_fk = %s ORDER BY pos_date DESC',
            ['integer'],
            [$oldFrmData->getTopPk()]
        );

        $last_post_src = '';
        $row = $this->db->fetchObject($res);
        if ($row !== null) {
            $last_post_src = $oldFrmData->getTopPk() . '#' . $row->pos_thr_fk . '#' . $row->pos_pk;
        }

        $this->db->manipulateF(
            'UPDATE frm_data ' .
            'SET top_num_posts = top_num_posts - %s, top_num_threads = top_num_threads - %s, visits = visits - %s, ' .
            'top_last_post = %s WHERE top_pk = %s',
            ['integer', 'integer', 'integer', 'text', 'integer'],
            [
                $num_moved_posts,
                $num_moved_threads,
                $num_visits,
                $last_post_src,
                $oldFrmData->getTopPk()
            ]
        );

        $this->db->setLimit(1, 0);
        $res = $this->db->queryF(
            'SELECT pos_thr_fk, pos_pk FROM frm_posts WHERE pos_top_fk = %s ORDER BY pos_date DESC',
            ['integer'],
            [$newFrmData->getTopPk()]
        );

        $last_post_dest = '';
        $row = $this->db->fetchObject($res);
        if ($row !== null) {
            $last_post_dest = $newFrmData->getTopPk() . '#' . $row->pos_thr_fk . '#' . $row->pos_pk;
        }

        $this->db->manipulateF(
            'UPDATE frm_data SET top_num_posts = top_num_posts + %s, top_num_threads = top_num_threads + %s, ' .
            'visits = visits + %s, top_last_post = %s WHERE top_pk = %s',
            ['integer', 'integer', 'integer', 'text', 'integer'],
            [$num_moved_posts, $num_moved_threads, $num_visits, $last_post_dest, $newFrmData->getTopPk()]
        );

        $this->event->raise(
            'components/ILIAS/Forum',
            'movedThreads',
            [
                'source_ref_id' => $src_forum->getId(),
                'target_ref_id' => $src_forum->getId(),
                'thread_ids' => $src_forum->getId(),
                'source_frm_obj_id' => $src_forum->getId(),
                'target_frm_obj_id' => $target_obj_id
            ]
        );

        return $errorMessages;
    }

    public function postCensorship(ilObjForum $forum, string $message, int $pos_pk, int $cens = 0): void
    {
        $cens_date = date('Y-m-d H:i:s');

        $this->db->manipulateF(
            'UPDATE frm_posts
                        SET pos_cens_com = %s,
                                pos_cens_date = %s,
                                pos_cens = %s,
                                update_user = %s
                        WHERE pos_pk = %s',
            ['text', 'timestamp', 'integer', 'integer', 'integer'],
            [$message,
             $cens_date,
             $cens,
             $this->user->getId(),
             $pos_pk
            ]
        );

        $news_id = ilNewsItem::getFirstNewsIdForContext(
            $this->id,
            'frm',
            $pos_pk,
            'pos'
        );
        if ($news_id > 0) {
            if ($cens > 0) {
                $news_item = new ilNewsItem($news_id);
                $news_item->setContent(nl2br($this->prepareText($message, 0)));
                $news_item->setContentHtml(false);
                if ($message !== strip_tags($message)) {
                    $news_item->setContentHtml(true);
                }
            } else {
                $res = $this->db->queryF('SELECT pos_message FROM frm_posts WHERE pos_pk = %s', ['integer'], [$pos_pk]);
                $rec = $this->db->fetchAssoc($res);

                $news_item = new ilNewsItem($news_id);
                $news_item->setContent(nl2br($this->prepareText($rec['pos_message'], 0)));
                $news_item->setContentHtml(false);
                if ($rec['pos_message'] !== strip_tags($rec['pos_message'])) {
                    $news_item->setContentHtml(true);
                }
            }
            $news_item->update();
        }

        $this->event->raise(
            'components/ILIAS/Forum',
            'censoredPost',
            [
                'ref_id' => $this->getForumRefId(),
                'post' => new ilForumPost($pos_pk),
                'object' => $forum
            ]
        );
    }

    public function deletePost($postIdOrRecord, bool $raiseEvents = true): int
    {
        $p_node = $postIdOrRecord;
        if (is_numeric($postIdOrRecord)) {
            $p_node = $this->getPostNode($postIdOrRecord);
        }

        $post = new ilForumPost((int) $p_node['pos_pk']);
        if ($raiseEvents) {
            $is_deleted_thread = ($post->getParentId() == 0) ? true : false;
            $num_visible_active_posts = 0;
            if ($is_deleted_thread) {
                $query = '
                    SELECT COUNT(*) AS cnt
                    FROM frm_posts
                    INNER JOIN frm_posts_tree ON pos_pk = pos_fk
                    WHERE frm_posts_tree.parent_pos != 0
                    AND pos_thr_fk = ' . $this->db->quote($post->getThreadId(), 'integer') . '
                    AND pos_status = ' . $this->db->quote(1, 'integer');
                $res = $this->db->query($query);
                $row = $this->db->fetchAssoc($res);
                $num_visible_active_posts = (int) ($row['cnt'] ?? 0);
            }

            $this->event->raise(
                'components/ILIAS/Forum',
                'beforePostDeletion',
                [
                    'obj_id' => $this->getForumId(),
                    'ref_id' => $this->getForumRefId(),
                    'post' => $post,
                    'thread_deleted' => $is_deleted_thread,
                    'num_visible_active_posts' => $num_visible_active_posts
                ]
            );
        }

        $this->deletePostFiles(array_merge(
            $this->getSubPathIdsForNode($post),
            [$post->getId()]
        ));

        $affected_user_ids[] = $post->getPosAuthorId();
        $deleted_post_ids = $this->deletePostTree($p_node);

        $obj_history = new ilForumDraftsHistory();
        $obj_history->deleteHistoryByPostIds($deleted_post_ids);

        $obj_draft = new ilForumPostDraft();
        $obj_draft->deleteDraftsByPostIds($deleted_post_ids);

        foreach ($deleted_post_ids as $post_id) {
            ilObjForum::_deleteReadEntries($post_id);
        }

        $dead_pos = count($deleted_post_ids);
        $dead_thr = 0;

        if ((int) $post->getParentId() === 0) {
            $dead_thr = $post->getThreadId();

            $this->db->manipulateF('DELETE FROM frm_threads WHERE thr_pk = %s', ['integer'], [$dead_thr]);
            $this->db->manipulateF(
                'UPDATE frm_data SET top_num_threads = top_num_threads - 1 WHERE top_frm_fk = %s',
                ['integer'],
                [$this->id]
            );

            $posset = $this->db->queryF('SELECT * FROM frm_posts WHERE pos_thr_fk = %s', ['integer'], [$dead_thr]);
            while ($posrec = $this->db->fetchAssoc($posset)) {
                $news_id = ilNewsItem::getFirstNewsIdForContext(
                    $this->id,
                    'frm',
                    (int) $posrec['pos_pk'],
                    'pos'
                );
                if ($news_id > 0) {
                    $news_item = new ilNewsItem($news_id);
                    $news_item->delete();
                }

                try {
                    $mobs = ilObjMediaObject::_getMobsOfObject('frm:html', (int) $posrec['pos_pk']);
                    foreach ($mobs as $mob) {
                        if (ilObjMediaObject::_exists($mob)) {
                            ilObjMediaObject::_removeUsage($mob, 'frm:html', (int) $posrec['pos_pk']);
                            $mob_obj = new ilObjMediaObject($mob);
                            $mob_obj->delete();
                        }
                    }
                } catch (Exception) {
                }
                $affected_user_ids[] = (int) $posrec['pos_author_id'];
            }

            $this->db->manipulateF('DELETE FROM frm_posts WHERE pos_thr_fk = %s', ['integer'], [$post->getThreadId()]);
        } else {
            for ($i = 0; $i < $dead_pos; $i++) {
                $this->db->manipulateF('DELETE FROM frm_posts WHERE pos_pk = %s', ['integer'], [$deleted_post_ids[$i]]);

                $news_id = ilNewsItem::getFirstNewsIdForContext(
                    $this->id,
                    'frm',
                    $deleted_post_ids[$i],
                    'pos'
                );
                if ($news_id > 0) {
                    $news_item = new ilNewsItem($news_id);
                    $news_item->delete();
                }

                try {
                    $mobs = ilObjMediaObject::_getMobsOfObject('frm:html', $deleted_post_ids[$i]);
                    foreach ($mobs as $mob) {
                        if (ilObjMediaObject::_exists($mob)) {
                            ilObjMediaObject::_removeUsage($mob, 'frm:html', $deleted_post_ids[$i]);
                            $mob_obj = new ilObjMediaObject($mob);
                            $mob_obj->delete();
                        }
                    }
                } catch (Exception) {
                }
            }

            $this->db->manipulateF(
                'UPDATE frm_threads SET thr_num_posts = thr_num_posts - %s WHERE thr_pk = %s',
                ['integer', 'integer'],
                [$dead_pos, $post->getTreeId()]
            );

            $res1 = $this->db->queryF(
                'SELECT * FROM frm_posts WHERE pos_thr_fk = %s ORDER BY pos_date DESC',
                ['integer'],
                [$post->getTreeId()]
            );

            $lastPost_thr = '';
            if ($res1->numRows() > 0) {
                $z = 0;

                while ($selData = $this->db->fetchAssoc($res1)) {
                    if ($z > 0) {
                        break;
                    }

                    $lastPost_thr = $selData['pos_top_fk'] . '#' . $selData['pos_thr_fk'] . '#' . $selData['pos_pk'];
                    $z++;
                }
            }

            $this->db->manipulateF(
                'UPDATE frm_threads SET thr_last_post = %s WHERE thr_pk = %s',
                ['text', 'integer'],
                [$lastPost_thr, $post->getTreeId()]
            );
        }

        $this->db->manipulateF(
            'UPDATE frm_data SET top_num_posts = top_num_posts - %s WHERE top_frm_fk = %s',
            ['integer', 'integer'],
            [$dead_pos, $this->id]
        );

        $res2 = $this->db->queryF(
            'SELECT * FROM frm_posts, frm_data WHERE pos_top_fk = top_pk AND top_frm_fk = %s ORDER BY pos_date DESC',
            ['integer'],
            [$this->id]
        );

        $lastPost_top = '';
        if ($res2->numRows() > 0) {
            $z = 0;

            while ($selData = $this->db->fetchAssoc($res2)) {
                if ($z > 0) {
                    break;
                }

                $lastPost_top = $selData['pos_top_fk'] . '#' . $selData['pos_thr_fk'] . '#' . $selData['pos_pk'];
                $z++;
            }
        }

        $this->db->manipulateF(
            'UPDATE frm_data SET top_last_post = %s WHERE top_frm_fk = %s',
            ['text', 'integer'],
            [$lastPost_top, $this->id]
        );

        if ($raiseEvents) {
            $this->event->raise(
                'components/ILIAS/Forum',
                'afterPostDeletion',
                [
                    'obj_id' => $this->getForumId(),
                    'ref_id' => $this->getForumRefId(),
                    'user_ids' => $affected_user_ids
                ]
            );
        }

        return $dead_thr;
    }

    public function getAllThreads(int $a_topic_id, array $params = [], int $limit = 0, int $offset = 0): array
    {
        $frm_props = ilForumProperties::getInstance($this->getForumId());
        $is_post_activation_enabled = $frm_props->isPostActivationEnabled();

        $user_id = $this->user->getId();

        $excluded_ids_condition = '';
        if (isset($params['excluded_ids']) && is_array($params['excluded_ids']) && $params['excluded_ids']) {
            $excluded_ids_condition = ' AND ' . $this->db->in('thr_pk', $params['excluded_ids'], true, 'integer') . ' ';
        }

        if (!isset($params['order_column']) || !in_array(
            strtolower($params['order_column']),
            ['lp_date', 'rating', 'thr_subject', 'num_posts', 'num_visit']
        )) {
            $params['order_column'] = 'post_date';
        }
        if (!isset($params['order_direction']) || !in_array(strtolower($params['order_direction']), ['asc', 'desc'])) {
            $params['order_direction'] = 'desc';
        }

        $cnt_active_pos_query = '';
        $cnt_join_type = 'LEFT';
        if ($is_post_activation_enabled && !$params['is_moderator']) {
            $cnt_active_pos_query = " AND (pos_status = {$this->db->quote(1, 'integer')} OR pos_author_id = {$this->db->quote($user_id, 'integer')}) ";
            $cnt_join_type = "INNER";
        }
        $query =
            "SELECT COUNT(DISTINCT(thr_pk)) cnt
                         FROM frm_threads
                         $cnt_join_type JOIN frm_posts
                                ON pos_thr_fk = thr_pk $cnt_active_pos_query
                         WHERE thr_top_fk = %s $excluded_ids_condition
                ";
        $res = $this->db->queryF($query, ['integer'], [$a_topic_id]);
        $cntData = $this->db->fetchAssoc($res);
        $cnt = (int) $cntData['cnt'];

        $active_query = '';
        $having = '';
        if ($is_post_activation_enabled && !$params['is_moderator']) {
            $active_query = ' AND (pos_status = %s OR pos_author_id = %s) ';
            $having = ' HAVING num_posts > 0';
        }

        $threads = [];
        $data = [];
        $data_types = [];

        $optional_fields = '';
        if ($frm_props->isIsThreadRatingEnabled()) {
            $optional_fields = ', avg_rating';
        }

        $additional_sort = '';

        if ($params['order_column'] === 'thr_subject') {
            $dynamic_columns = [', thr_subject ' . $params['order_direction']];
        } elseif ($params['order_column'] === 'num_posts') {
            $dynamic_columns = [', num_posts ' . $params['order_direction']];
        } elseif ($params['order_column'] === 'num_visit') {
            $dynamic_columns = [', visits ' . $params['order_direction']];
        } else {
            $dynamic_columns = [', post_date ' . $params['order_direction']];
        }

        if ($frm_props->isIsThreadRatingEnabled()) {
            $dynamic_columns[] = ' ,avg_rating ' . $params['order_direction'];
        }
        if ('rating' === strtolower($params['order_column'])) {
            $dynamic_columns = array_reverse($dynamic_columns);
        }
        $additional_sort .= implode(' ', $dynamic_columns);


        if (!$this->user->isAnonymous()) {
            $query = "SELECT
                                          (CASE WHEN COUNT(DISTINCT(notification_id)) > 0 THEN 1 ELSE 0 END) usr_notification_is_enabled,
                                          MAX(pos_date) post_date,
                                          SUM(tree1.parent_pos != 0) num_posts, 
                                          SUM(tree1.parent_pos != 0) - SUM(tree1.parent_pos != 0 AND postread.post_id IS NOT NULL) num_unread_posts, ";

            $query .= " thr_pk, thr_top_fk, thr_subject, thr_author_id, thr_display_user_id, thr_usr_alias, thr_num_posts, thr_last_post, thr_date, thr_update, visits, frm_threads.import_name, is_sticky, is_closed
                                          $optional_fields
                                          FROM frm_threads
                                          
                                          LEFT JOIN frm_notification
                                                ON frm_notification.thread_id = thr_pk
                                                AND frm_notification.user_id = %s
                                          
                                          LEFT JOIN frm_posts
                                                ON pos_thr_fk = thr_pk $active_query
                                          LEFT JOIN frm_posts_tree tree1
                                            ON tree1.pos_fk = frm_posts.pos_pk 
                                          LEFT JOIN frm_user_read postread
                                                ON postread.post_id = pos_pk
                                                AND postread.usr_id = %s";

            $query .= " WHERE thr_top_fk = %s
                                                $excluded_ids_condition
                                                GROUP BY thr_pk, thr_top_fk, thr_subject, thr_author_id, thr_display_user_id, thr_usr_alias, thr_num_posts, thr_last_post, thr_date, thr_update, visits, frm_threads.import_name, is_sticky, is_closed
                                                $optional_fields
                                                $having
                                                ORDER BY is_sticky DESC $additional_sort, thr_date DESC";


            $data_types[] = 'integer';
            if ($is_post_activation_enabled && !$params['is_moderator']) {
                $data_types[] = 'integer';
                $data_types[] = 'integer';
            }
            $data_types[] = 'integer';
            $data_types[] = 'integer';


            $data[] = $user_id;
            if ($is_post_activation_enabled && !$params['is_moderator']) {
                $data[] = 1;
                $data[] = $user_id;
            }
            $data[] = $user_id;
        } else {
            $query = "SELECT
                                          0 usr_notification_is_enabled,
                                          MAX(pos_date) post_date,
                                          COUNT(DISTINCT(tree1.pos_fk)) num_posts,
                                          COUNT(DISTINCT(tree1.pos_fk)) num_unread_posts,
                                          thr_pk, thr_top_fk, thr_subject, thr_author_id, thr_display_user_id, thr_usr_alias, thr_num_posts, thr_last_post, thr_date, thr_update, visits, frm_threads.import_name, is_sticky, is_closed
                                          $optional_fields
                                          FROM frm_threads
                                          
                                          LEFT JOIN frm_posts
                                                ON pos_thr_fk = thr_pk $active_query
                                          LEFT JOIN frm_posts_tree tree1
                                            ON tree1.pos_fk = frm_posts.pos_pk AND tree1.parent_pos != 0
                                        ";

            $query .= " WHERE thr_top_fk = %s
                                                $excluded_ids_condition
                                                GROUP BY thr_pk, thr_top_fk, thr_subject, thr_author_id, thr_display_user_id, thr_usr_alias, thr_num_posts, thr_last_post, thr_date, thr_update, visits, frm_threads.import_name, is_sticky, is_closed
                                                $optional_fields
                                                $having
                                                ORDER BY is_sticky DESC $additional_sort, thr_date DESC";

            if ($is_post_activation_enabled && !$params['is_moderator']) {
                $data_types[] = 'integer';
                $data_types[] = 'integer';
            }
            $data_types[] = 'integer';
            if ($is_post_activation_enabled && !$params['is_moderator']) {
                $data[] = 1;
                $data[] = $user_id;
            }
        }
        $data[] = $a_topic_id;

        if ($limit || $offset) {
            $this->db->setLimit($limit, $offset);
        }

        $threadIds = [];
        $res = $this->db->queryF($query, $data_types, $data);
        while ($row = $this->db->fetchAssoc($res)) {
            $thread = new ilForumTopic((int) $row['thr_pk'], (bool) $params['is_moderator'], true);
            $thread->assignData($row);
            $threads[(int) $row['thr_pk']] = $thread;
            $threadIds[] = (int) $row['thr_pk'];
        }

        $inner_last_active_post_condition = '';
        if ($is_post_activation_enabled && !$params['is_moderator']) {
            $inner_last_active_post_condition = sprintf(
                ' AND (iposts.pos_status = %s OR (iposts.pos_status = %s AND iposts.pos_author_id = %s)) ',
                $this->db->quote(1, 'integer'),
                $this->db->quote(0, 'integer'),
                $this->db->quote($this->user->getId(), 'integer')
            );
        }

        $post_res = $this->db->query(
            'SELECT frm_posts.*
                        FROM frm_posts
                        INNER JOIN (
                                SELECT pos_thr_fk, MAX(iposts.pos_date) i_pos_date
                                FROM frm_posts iposts
                                WHERE ' . $this->db->in('iposts.pos_thr_fk', $threadIds, false, 'integer') . ' 
                                ' . $inner_last_active_post_condition . '
                                GROUP BY pos_thr_fk
                        ) opost ON frm_posts.pos_thr_fk = opost.pos_thr_fk AND frm_posts.pos_date = opost.i_pos_date'
        );
        while ($post_row = $this->db->fetchAssoc($post_res)) {
            $tmp_obj = new ilForumPost((int) $post_row['pos_pk'], (bool) $params['is_moderator'], true);
            $tmp_obj->setPosAuthorId((int) $post_row['pos_author_id']);
            $tmp_obj->setDisplayUserId((int) $post_row['pos_display_user_id']);
            $tmp_obj->setUserAlias((string) $post_row['pos_usr_alias']);
            $tmp_obj->setImportName((string) $post_row['import_name']);
            $tmp_obj->setId((int) $post_row['pos_pk']);
            $tmp_obj->setCreateDate((string) $post_row['pos_date']);

            $threads[(int) $post_row['pos_thr_fk']]->setLastPostForThreadOverview($tmp_obj);
        }

        return [
            'items' => $threads,
            'cnt' => $cnt
        ];
    }

    public function getNumberOfPublishedUserPostings(int $usr_id, bool $post_activation_required): int
    {
        $query = '
            SELECT 
                   SUM(IF(f.pos_cens = %s, 1, 0)) cnt
            FROM frm_posts f
            INNER JOIN frm_posts_tree t ON f.pos_pk = t.pos_fk AND t.parent_pos != %s
            INNER JOIN frm_threads th ON t.thr_fk = th.thr_pk 
            INNER JOIN frm_data d ON d.top_pk = f.pos_top_fk AND d.top_frm_fk = %s
            WHERE f.pos_author_id = %s
        ';

        if ($post_activation_required) {
            $query .= ' AND f.pos_status = ' . $this->db->quote(1, 'integer');
        }

        $res = $this->db->queryF(
            $query,
            ['integer', 'integer', 'integer', 'integer'],
            [0, 0, $this->getForumId(), $usr_id]
        );
        $row = $this->db->fetchAssoc($res);
        if (is_array($row)) {
            return (int) $row['cnt'];
        }

        return 0;
    }

    public function getUserStatistics(bool $post_activation_required): array
    {
        $statistic = [];
        $data_types = [];
        $data = [];

        $query = '
            SELECT 
                   u.login, u.lastname, u.firstname, f.pos_author_id, u.usr_id,
                   p.value public_profile,
                   SUM(IF(f.pos_cens = %s, 1, 0)) num_postings
            FROM frm_posts f
            INNER JOIN frm_posts_tree t ON f.pos_pk = t.pos_fk
            INNER JOIN frm_threads th ON t.thr_fk = th.thr_pk
            INNER JOIN usr_data u ON u.usr_id = f.pos_author_id
            INNER JOIN frm_data d ON d.top_pk = f.pos_top_fk
            LEFT JOIN usr_pref p ON p.usr_id = u.usr_id AND p.keyword = %s
            WHERE t.parent_pos != %s
        ';

        $data_types[] = 'integer';
        $data_types[] = 'text';
        $data_types[] = 'integer';
        $data[] = 0;
        $data[] = 'public_profile';
        $data[] = 0;

        if ($post_activation_required) {
            $query .= ' AND pos_status = %s';
            $data_types[] = 'integer';
            $data[] = 1;
        }

        $query .= '
            AND d.top_frm_fk = %s
            GROUP BY u.login, p.value,u.lastname, u.firstname, f.pos_author_id
        ';

        $data_types[] = 'integer';
        $data[] = $this->getForumId();

        $res = $this->db->queryF($query, $data_types, $data);
        while ($row = $this->db->fetchAssoc($res)) {
            if (
                !in_array($row['public_profile'], [
                    PersonalProfileMode::PROFILE_ENABLED_LOGGED_IN_USERS,
                    PersonalProfileMode::PROFILE_ENABLED_GLOBAL], true)
                || ($this->user->isAnonymous() && $row['public_profile'] !== PersonalProfileMode::PROFILE_ENABLED_GLOBAL)
            ) {
                $row['lastname'] = '';
                $row['firstname'] = '';
            }

            $row['usr_id'] = (int) $row['usr_id'];
            $row['pos_author_id'] = (int) $row['pos_author_id'];
            $row['num_postings'] = (int) $row['num_postings'];

            $statistic[] = $row;
        }

        return $statistic;
    }

    public function getRootPostIdByThread(int $a_thread_id): int
    {
        $res = $this->db->queryF(
            'SELECT pos_fk FROM frm_posts_tree WHERE thr_fk = %s AND parent_pos = %s',
            ['integer', 'integer'],
            [$a_thread_id, 0]
        );

        $row = $this->db->fetchObject($res);
        if ($row instanceof stdClass) {
            return (int) $row->pos_fk;
        }

        return 0;
    }

    public function getModerators(): array
    {
        return self::_getModerators($this->getForumRefId());
    }

    public static function _getModerators(int $a_ref_id): array
    {
        global $DIC;

        $rbacreview = $DIC->rbac()->review();

        $role_arr = $rbacreview->getRolesOfRoleFolder($a_ref_id);
        foreach ($role_arr as $role_id) {
            if (ilObject::_lookupTitle($role_id) === 'il_frm_moderator_' . $a_ref_id) {
                return array_map('intval', $rbacreview->assignedUsers($role_id));
            }
        }

        return [];
    }

    public static function _isModerator(int $a_ref_id, int $a_usr_id): bool
    {
        if (!isset(self::$moderators_by_ref_id_map[$a_ref_id])) {
            self::$moderators_by_ref_id_map[$a_ref_id] = self::_getModerators($a_ref_id);
        }

        return in_array($a_usr_id, self::$moderators_by_ref_id_map[$a_ref_id], true);
    }

    public function countUserArticles(int $a_user_id): int
    {
        $res = $this->db->queryF(
            'SELECT * FROM frm_data
                        INNER JOIN frm_posts ON pos_top_fk = top_pk
                        INNER JOIN frm_posts_tree tree1 ON tree1.pos_fk = frm_posts.pos_pk AND tree1.parent_pos != 0  
                        WHERE top_frm_fk = %s
                        AND pos_author_id = %s',
            ['integer', 'integer'],
            [$this->getForumId(), $a_user_id]
        );

        return $res->numRows();
    }

    public function countActiveUserArticles(int $a_user_id): int
    {
        $res = $this->db->queryF(
            'SELECT * FROM frm_data
                        INNER JOIN frm_posts ON pos_top_fk = top_pk
                        INNER JOIN frm_posts_tree tree1 ON tree1.pos_fk = frm_posts.pos_pk AND tree1.parent_pos != 0
                        WHERE top_frm_fk = %s
                        AND (pos_status = %s OR (pos_status = %s AND pos_author_id = %s))
                        AND pos_author_id = %s',
            ['integer', 'integer', 'integer', 'integer', 'integer'],
            [$this->getForumId(), 1, 0, $this->user->getId(), $a_user_id]
        );

        return $res->numRows();
    }

    public function convertDate(string $date): string
    {
        return ilDatePresentation::formatDate(new ilDateTime($date, IL_CAL_DATETIME));
    }

    public function addPostTree(int $a_tree_id, int $a_node_id = -1, string $a_date = ''): bool
    {
        $a_date = $a_date ?: date('Y-m-d H:i:s');

        if ($a_node_id <= 0) {
            $a_node_id = $a_tree_id;
        }

        $nextId = $this->db->nextId('frm_posts_tree');

        $this->db->manipulateF(
            '
                        INSERT INTO frm_posts_tree
                        (       fpt_pk,
                                thr_fk,
                                pos_fk,
                                parent_pos,
                                lft,
                                rgt,
                                depth,
                                fpt_date
                        )
                        VALUES(%s, %s, %s, %s,  %s,  %s, %s, %s )',
            ['integer', 'integer', 'integer', 'integer', 'integer', 'integer', 'integer', 'timestamp'],
            [$nextId, $a_tree_id, $a_node_id, 0, 1, 2, 1, $a_date]
        );

        return true;
    }

    public function insertPostNode(int $a_node_id, int $a_parent_id, int $tree_id, string $a_date = ''): void
    {
        $a_date = $a_date ?: date('Y-m-d H:i:s');
        $left = 1;

        $res = $this->db->queryF(
            'SELECT lft FROM frm_posts_tree WHERE pos_fk = %s AND thr_fk = %s',
            ['integer', 'integer'],
            [$a_parent_id, $tree_id]
        );
        $row = $this->db->fetchObject($res);
        if ($row instanceof stdClass) {
            $left = (int) $row->lft;
        }

        $lft = $left + 1;
        $rgt = $left + 2;

        $this->db->manipulateF(
            '
                        UPDATE frm_posts_tree 
                        SET  lft = CASE 
                                 WHEN lft > %s
                                 THEN lft + 2 
                                 ELSE lft 
                                 END, 
                                 rgt = CASE 
                                 WHEN rgt > %s
                                 THEN rgt + 2 
                                 ELSE rgt 
                                 END 
                                 WHERE thr_fk = %s',
            ['integer', 'integer', 'integer'],
            [$left, $left, $tree_id]
        );

        $depth = $this->getPostDepth($a_parent_id, $tree_id) + 1;

        $nextId = $this->db->nextId('frm_posts_tree');
        $this->db->manipulateF(
            '
                        INSERT INTO frm_posts_tree
                        (       fpt_pk,
                                thr_fk,
                                pos_fk,
                                parent_pos,
                                lft,
                                rgt,
                                depth,
                                fpt_date
                        )
                        VALUES(%s,%s,%s, %s, %s, %s,%s, %s)',
            ['integer', 'integer', 'integer', 'integer', 'integer', 'integer', 'integer', 'timestamp'],
            [
                $nextId,
                $tree_id,
                $a_node_id,
                $a_parent_id,
                $lft,
                $rgt,
                $depth,
                $a_date
            ]
        );
    }

    public function getPostDepth(int $a_node_id, int $tree_id): int
    {
        if ($tree_id !== 0) {
            $res = $this->db->queryF(
                'SELECT depth FROM frm_posts_tree WHERE pos_fk = %s AND thr_fk = %s',
                ['integer', 'integer'],
                [$a_node_id, $tree_id]
            );

            $row = $this->db->fetchObject($res);
            if ($row instanceof stdClass) {
                return (int) $row->depth;
            }
        }

        return 0;
    }

    public function getFirstPostNode(int $tree_id): array
    {
        $res = $this->db->queryF(
            'SELECT * FROM frm_posts, frm_posts_tree WHERE pos_pk = pos_fk AND parent_pos = %s AND thr_fk = %s',
            ['integer', 'integer'],
            [0, $tree_id]
        );

        if (($row = $this->db->fetchObject($res)) !== null) {
            return $this->fetchPostNodeData($row);
        }

        return [];
    }

    public function getPostNode(int $post_id): array
    {
        $res = $this->db->queryF(
            'SELECT * FROM frm_posts, frm_posts_tree WHERE pos_pk = pos_fk AND pos_pk = %s',
            ['integer'],
            [$post_id]
        );

        if (($row = $this->db->fetchObject($res)) !== null) {
            return $this->fetchPostNodeData($row);
        }

        return [];
    }

    public function fetchPostNodeData(stdClass $a_row): array
    {
        $fullname = '';
        $loginname = '';

        if (ilObject::_exists((int) $a_row->pos_display_user_id)) {
            $tmp_user = new ilObjUser((int) $a_row->pos_display_user_id);
            $fullname = $tmp_user->getFullname();
            $loginname = $tmp_user->getLogin();
        }

        if ($fullname === '') {
            $fullname = $this->lng->txt('unknown');
            if ($a_row->import_name) {
                $fullname = $a_row->import_name;
            }
        }

        return [
            'type' => 'post',
            'pos_pk' => (int) $a_row->pos_pk,
            'pos_thr_fk' => (int) $a_row->pos_thr_fk,
            'child' => (int) $a_row->pos_pk,
            'author' => (int) $a_row->pos_display_user_id,
            'alias' => (string) $a_row->pos_usr_alias,
            'title' => $fullname,
            'loginname' => $loginname,
            'message' => (string) $a_row->pos_message,
            'subject' => (string) $a_row->pos_subject,
            'pos_cens_com' => (string) $a_row->pos_cens_com,
            'pos_cens' => (int) $a_row->pos_cens,
            'date' => $a_row->fpt_date,
            'create_date' => $a_row->pos_date,
            'update' => $a_row->pos_update,
            'update_user' => (int) $a_row->update_user,
            'tree' => (int) $a_row->thr_fk,
            'parent' => (int) $a_row->parent_pos,
            'lft' => (int) $a_row->lft,
            'rgt' => (int) $a_row->rgt,
            'depth' => (int) $a_row->depth,
            'id' => (int) $a_row->fpt_pk,
            'notify' => (int) $a_row->notify,
            'import_name' => $a_row->import_name,
            'pos_status' => (int) $a_row->pos_status
        ];
    }

    public function getSubPathIdsForNode(ilForumPost $post): array
    {
        $res = $this->db->queryF(
            'SELECT pos_fk FROM frm_posts_tree WHERE lft BETWEEN %s AND %s AND thr_fk = %s',
            [ilDBConstants::T_INTEGER, ilDBConstants::T_INTEGER, ilDBConstants::T_INTEGER],
            [$post->getLft(), $post->getRgt(), $post->getTreeId()]
        );

        $post_ids = [];
        while ($post_tree_data = $this->db->fetchAssoc($res)) {
            $post_ids[] = (int) $post_tree_data['pos_fk'];
        }

        return $post_ids;
    }

    public function deletePostTree(array $a_node): array
    {
        $res = $this->db->queryF(
            'SELECT lft, rgt FROM frm_posts_tree WHERE thr_fk = %s AND pos_fk = %s AND parent_pos = %s',
            ['integer', 'integer', 'integer'],
            [$a_node['tree'], $a_node['pos_pk'], $a_node['parent']]
        );

        while ($row = $this->db->fetchObject($res)) {
            $a_node['lft'] = (int) $row->lft;
            $a_node['rgt'] = (int) $row->rgt;
        }

        $diff = $a_node['rgt'] - $a_node['lft'] + 1;

        $res = $this->db->queryF(
            'SELECT pos_fk FROM frm_posts_tree WHERE lft BETWEEN %s AND %s AND thr_fk = %s',
            ['integer', 'integer', 'integer'],
            [$a_node['lft'], $a_node['rgt'], $a_node['tree']]
        );

        $deleted_post_ids = [];
        while ($treeData = $this->db->fetchAssoc($res)) {
            $deleted_post_ids[] = (int) $treeData['pos_fk'];
        }

        $this->db->manipulateF(
            'DELETE FROM frm_posts_tree WHERE lft BETWEEN %s AND %s AND thr_fk = %s',
            ['integer', 'integer', 'integer'],
            [$a_node['lft'], $a_node['rgt'], $a_node['tree']]
        );

        $this->db->manipulateF(
            '
                        UPDATE frm_posts_tree 
                        SET lft = CASE 
                                                WHEN lft > %s
                                                THEN lft - %s
                                                ELSE lft 
                                                END, 
                                rgt = CASE 
                                                WHEN rgt > %s
                                                THEN rgt - %s
                                                ELSE rgt 
                                                END 
                        WHERE thr_fk = %s',
            ['integer', 'integer', 'integer', 'integer', 'integer'],
            [$a_node['lft'], $diff, $a_node['lft'], $diff, $a_node['tree']]
        );

        return $deleted_post_ids;
    }

    public function updateVisits(int $ID): void
    {
        $checkTime = time() - (60 * 60);
        $session_key = 'frm_visit_' . $this->dbTable . '_' . $ID;

        if (ilSession::get($session_key) < $checkTime) {
            ilSession::set($session_key, time());
            $query = 'UPDATE ' . $this->dbTable . ' SET visits = visits + 1 WHERE ';
            $data_type = [];
            $data_value = [];

            if ($this->getMDB2Query() !== '' && $this->getMDB2DataType() !== [] && $this->getMDB2DataValue() !== []) {
                $query .= $this->getMDB2Query();
                $data_type += $this->getMDB2DataType();
                $data_value += $this->getMDB2DataValue();

                $this->db->manipulateF($query, $data_type, $data_value);
            }
        }
    }

    public function prepareText(string $text, int $edit = 0, string $quote_user = '', string $type = ''): string
    {
        if ($type === 'export') {
            $this->replQuote1 = "<blockquote class=\"quote\"><hr size=\"1\" color=\"#000000\">";
            $this->replQuote2 = "<hr size=\"1\" color=\"#000000\"/></blockquote>";
        }

        if ($edit === 1) {
            $lname = '';
            if ($quote_user !== '') {
                $lname = '="' . $quote_user . '"';
            }

            $text = "[quote$lname]" . $text . "[/quote]";
        } else {
            // check for quotation
            $startZ = substr_count($text, "[quote"); // also count [quote="..."]
            $endZ = substr_count($text, "[/quote]");

            if ($startZ > 0 || $endZ > 0) {
                // add missing opening and closing tags
                if ($startZ > $endZ) {
                    $diff = $startZ - $endZ;

                    for ($i = 0; $i < $diff; $i++) {
                        if ($type === 'export') {
                            $text .= $this->txtQuote2;
                        } else {
                            $text .= "[/quote]";
                        }
                    }
                } elseif ($startZ < $endZ) {
                    $diff = $endZ - $startZ;

                    for ($i = 0; $i < $diff; $i++) {
                        if ($type === 'export') {
                            $text = $this->txtQuote1 . $text;
                        } else {
                            $text = "[quote]" . $text;
                        }
                    }
                }

                if ($edit === 0) {
                    $text = preg_replace(
                        '@\[(quote\s*?=\s*?"([^"]*?)"\s*?)\]@i',
                        $this->replQuote1 . '<div class="ilForumQuoteHead">' . $this->lng->txt('quote') . ' ($2)</div>',
                        $text
                    );

                    $text = str_replace(
                        ["[quote]", "[/quote]"],
                        [
                            $this->replQuote1 . '<div class="ilForumQuoteHead">' . $this->lng->txt('quote') . '</div>',
                            $this->replQuote2
                        ],
                        $text
                    );
                }
            }
        }

        if ($type !== 'export') {
            if ($edit === 0) {
                $text = ilMathJax::getInstance()->insertLatexImages($text, "<span class\=\"latex\">", "<\/span>");
                $text = ilMathJax::getInstance()->insertLatexImages($text, "\[tex\]", "\[\/tex\]");
            }

            // workaround for preventing template engine
            // from hiding text that is enclosed
            // in curly brackets (e.g. "{a}")
            $text = str_replace(["{", "}"], ["&#123;", "&#125;"], $text);
        }

        return $text;
    }

    private function deletePostFiles(array $a_ids): void
    {
        foreach ($a_ids as $pos_id) {
            $forumFiles = new ilFileDataForum($this->getForumId(), $pos_id);
            $files = $forumFiles->getFilesOfPost();
            foreach ($files as $file) {
                $forumFiles->unlinkFile($file['name']);
            }
        }
    }

    public function getImportName(): string
    {
        return $this->import_name;
    }

    public function setImportName(string $a_import_name): void
    {
        $this->import_name = $a_import_name;
    }

    public function enableForumNotification(int $user_id): bool
    {
        if (!$this->isForumNotificationEnabled($user_id)) {
            /* Remove all notifications of threads that belong to the forum */
            $res = $this->db->queryF(
                '
                                SELECT frm_notification.thread_id FROM frm_data, frm_notification, frm_threads 
                                WHERE frm_notification.user_id = %s
                                AND frm_notification.thread_id = frm_threads.thr_pk 
                                AND frm_threads.thr_top_fk = frm_data.top_pk 
                                AND frm_data.top_frm_fk = %s
                                GROUP BY frm_notification.thread_id',
                ['integer', 'integer'],
                [$user_id, $this->id]
            );

            if ($res->numRows() > 0) {
                $thread_data = [];
                $thread_data_types = [];

                $query = ' DELETE FROM frm_notification WHERE user_id = %s AND thread_id IN (';
                $thread_data[] = $user_id;
                $thread_data_types[] = 'integer';

                $counter = 1;
                while ($row = $this->db->fetchAssoc($res)) {
                    if ($counter < $res->numRows()) {
                        $query .= '%s, ';
                        $thread_data[] = $row['thread_id'];
                        $thread_data_types[] = 'integer';
                    }

                    if ($counter === $res->numRows()) {
                        $query .= '%s)';
                        $thread_data[] = $row['thread_id'];
                        $thread_data_types[] = 'integer';
                    }
                    $counter++;
                }

                $this->db->manipulateF($query, $thread_data_types, $thread_data);
            }

            /* Insert forum notification */
            $nextId = $this->db->nextId('frm_notification');
            $this->db->manipulateF(
                'INSERT INTO frm_notification (notification_id, user_id, frm_id) VALUES(%s, %s, %s)',
                ['integer', 'integer', 'integer'],
                [$nextId, $user_id, $this->id]
            );
        }

        return true;
    }

    public function disableForumNotification(int $user_id): bool
    {
        $this->db->manipulateF(
            'DELETE FROM frm_notification WHERE user_id = %s AND frm_id = %s',
            ['integer', 'integer'],
            [$user_id, $this->id]
        );

        return true;
    }

    public function isForumNotificationEnabled(int $user_id): bool
    {
        $res = $this->db->queryF(
            'SELECT COUNT(*) cnt FROM frm_notification WHERE user_id = %s AND frm_id = %s',
            ['integer', 'integer'],
            [$user_id, $this->id]
        );

        if ($row = $this->db->fetchAssoc($res)) {
            return (int) $row['cnt'] > 0;
        }

        return false;
    }

    public function isThreadNotificationEnabled(int $user_id, int $thread_id): bool
    {
        $res = $this->db->queryF(
            'SELECT COUNT(*) cnt FROM frm_notification WHERE user_id = %s AND thread_id = %s',
            ['integer', 'integer'],
            [$user_id, $thread_id]
        );

        if ($row = $this->db->fetchAssoc($res)) {
            return (int) $row['cnt'] > 0;
        }

        return false;
    }

    public static function getSortedThreadSubjects(int $a_obj_id, int $a_sort_mode = self::SORT_DATE): array
    {
        global $DIC;

        $sort = match ($a_sort_mode) {
            self::SORT_DATE => 'thr_date',
            default => 'thr_subject',
        };

        $res = $DIC->database()->queryF(
            'SELECT thr_pk, thr_subject FROM frm_threads INNER JOIN frm_data ON top_pk = thr_top_fk WHERE top_frm_fk = %s ORDER BY %s',
            ['integer', 'text'],
            [$a_obj_id, $sort]
        );

        $threads = [];
        while ($row = $DIC->database()->fetchObject($res)) {
            $threads[(int) $row->thr_pk] = $row->thr_subject;
        }

        return $threads;
    }

    public static function _lookupObjIdForForumId(int $a_for_id): int
    {
        global $DIC;

        $res = $DIC->database()->queryF('SELECT top_frm_fk FROM frm_data WHERE top_pk = %s', ['integer'], [$a_for_id]);
        if ($row = $DIC->database()->fetchAssoc($res)) {
            return (int) $row['top_frm_fk'];
        }

        return 0;
    }

    public function mergeThreads(int $source_id, int $target_id): void
    {
        // selected source and target objects
        $sourceThread = new ilForumTopic($source_id);
        $targetThread = new ilForumTopic($target_id);

        if ($sourceThread->getForumId() !== $targetThread->getForumId()) {
            throw new ilException('not_allowed_to_merge_into_another_forum');
        }

        // use the 'older' thread as target
        if ($sourceThread->getCreateDate() > $targetThread->getCreateDate()) {
            $sourceThreadForMerge = $sourceThread;
            $targetThreadForMerge = $targetThread;
        } else {
            $sourceThreadForMerge = $targetThread;
            $targetThreadForMerge = $sourceThread;
        }

        $threadSubject = $targetThreadForMerge->getSubject();

        $targetWasClosedBeforeMerge = $targetThreadForMerge->isClosed();
        $sourceThreadForMerge->close();

        if (!$targetWasClosedBeforeMerge) {
            $targetThreadForMerge->close();
        }

        $allSourcePostings = $sourceThreadForMerge->getAllPostIds();
        $sourceThreadRootNode = $sourceThreadForMerge->getPostRootNode();
        $targetThreadRootNode = $targetThreadForMerge->getPostRootNode();

        $sourceThreadRootArray = $this->getPostNode($sourceThreadRootNode->getId());

        $ilAtomQuery = $this->db->buildAtomQuery();
        $ilAtomQuery->addTableLock('frm_posts');
        $ilAtomQuery->addTableLock('frm_posts_tree');
        $ilAtomQuery->addTableLock('frm_threads');
        $ilAtomQuery->addTableLock('frm_data');

        $ilAtomQuery->addQueryCallable(static function (ilDBInterface $ilDB) use (
            $targetThreadForMerge,
            $sourceThreadForMerge,
            $targetThreadRootNode,
            $sourceThreadRootNode,
            $allSourcePostings
        ): void {
            $targetRootNodeRgt = $targetThreadRootNode->getRgt();
            $targetRootNodeId = $targetThreadRootNode->getId();

            // update target root node rgt: Ignore the root node itself from the source (= -2)
            ilForumPostsTree::updateTargetRootRgt(
                $targetThreadRootNode->getId(),
                ($targetThreadRootNode->getRgt() + $sourceThreadRootNode->getRgt() - 2)
            );

            // get source post tree and update posts tree
            foreach ($allSourcePostings as $pos_pk) {
                $post_obj = new ilForumPost($pos_pk);

                if ($post_obj->getId() === $sourceThreadRootNode->getId()) {
                    // Ignore the source root node (MUST be deleted later)
                    continue;
                }

                $tree = new ilForumPostsTree();
                $tree->setPosFk($pos_pk);

                if ($post_obj->getParentId() === $sourceThreadRootNode->getId()) {
                    $tree->setParentPos($targetRootNodeId);
                } else {
                    $tree->setParentPos($post_obj->getParentId());
                }

                $tree->setLft(($post_obj->getLft() + $targetRootNodeRgt) - 2);
                $tree->setRgt(($post_obj->getRgt() + $targetRootNodeRgt) - 2);

                $tree->setDepth($post_obj->getDepth());
                $tree->setTargetThreadId($targetThreadForMerge->getId());
                $tree->setSourceThreadId($sourceThreadForMerge->getId());

                $tree->merge();
            }

            ilForumPost::mergePosts(
                $sourceThreadForMerge->getId(),
                $targetThreadForMerge->getId(),
                [$sourceThreadRootNode->getId()]
            );
        });
        $ilAtomQuery->run();

        ilForumNotification::mergeThreadNotifications($sourceThreadForMerge->getId(), $targetThreadForMerge->getId());
        ilObjForum::mergeForumUserRead($sourceThreadForMerge->getId(), $targetThreadForMerge->getId());

        $lastPostString = $targetThreadForMerge->getLastPostString() ?? '';
        $exp = explode('#', $lastPostString);
        if (array_key_exists(2, $exp)) {
            try {
                $exp[2] = $targetThreadForMerge->getLastPost()->getId();
                $lastPostString = implode('#', $exp);
            } catch (OutOfBoundsException) {
                $lastPostString = null;
            }
        }

        $frm_topic_obj = new ilForumTopic(0, false, true);
        $frm_topic_obj->setNumPosts($sourceThreadForMerge->getNumPosts() + $targetThreadForMerge->getNumPosts());
        $frm_topic_obj->setVisits($sourceThreadForMerge->getVisits() + $targetThreadForMerge->getVisits());
        $frm_topic_obj->setLastPostString($lastPostString);
        $frm_topic_obj->setSubject($threadSubject);
        $frm_topic_obj->setId($targetThreadForMerge->getId());
        $frm_topic_obj->updateMergedThread();

        if (!$targetWasClosedBeforeMerge) {
            $targetThreadForMerge->reopen();
        }

        $this->event->raise(
            'components/ILIAS/Forum',
            'mergedThreads',
            [
                'obj_id' => $this->getForumId(),
                'source_thread_id' => $sourceThreadForMerge->getId(),
                'target_thread_id' => $targetThreadForMerge->getId()
            ]
        );

        $this->deletePost($sourceThreadRootArray, false);
    }
}