BBP_BuddyPress_Activity::topic_create( int $topic_id, int $forum_id, array $anonymous_data = array(), int $topic_author_id )

	public function topic_create( $topic_id = 0, $forum_id = 0, $anonymous_data = array(), $topic_author_id = 0 ) {

		// Bail early if topic is by anonymous user
		if ( !empty( $anonymous_data ) )
			return;

		// Validate activity data
		$user_id  = (int) $topic_author_id;
		$topic_id = bbp_get_topic_id( $topic_id );
		$forum_id = bbp_get_forum_id( $forum_id );

		// Bail if user is not active
		if ( bbp_is_user_inactive( $user_id ) )
			return;

		// Bail if topic is not published
		if ( !bbp_is_topic_published( $topic_id ) )
			return;

		// User link for topic author
		$user_link = bbp_get_user_profile_link( $user_id  );

		// Topic
		$topic_permalink = bbp_get_topic_permalink( $topic_id );
		$topic_title     = get_post_field( 'post_title',   $topic_id, 'raw' );
		$topic_content   = get_post_field( 'post_content', $topic_id, 'raw' );
		$topic_link      = '<a href="' . $topic_permalink . '">' . $topic_title . '</a>';

		// Forum
		$forum_permalink = bbp_get_forum_permalink( $forum_id );
		$forum_title     = get_post_field( 'post_title', $forum_id, 'raw' );
		$forum_link      = '<a href="' . $forum_permalink . '">' . $forum_title . '</a>';

		// Activity action & text
		$activity_text    = sprintf( esc_html__( '%1$s started the discussion %2$s in the forum %3$s', 'buddyboss' ), $user_link, $topic_link, $forum_link );
		$activity_action  = apply_filters( 'bbp_activity_topic_create',         $activity_text, $user_id,   $topic_id,   $forum_id );
		$activity_content = apply_filters( 'bbp_activity_topic_create_excerpt', $topic_content                                     );

		// Compile and record the activity stream results
		$activity_id = $this->record_activity( array(
			'id'                => $this->get_activity_id( $topic_id ),
			'user_id'           => $user_id,
			'action'            => $activity_action,
			'content'           => $activity_content,
			'primary_link'      => $topic_permalink,
			'type'              => $this->topic_create,
			'item_id'           => $topic_id,
			'secondary_item_id' => $forum_id,
			'recorded_time'     => get_post_time( 'Y-m-d H:i:s', true, $topic_id ),
			'hide_sitewide'     => ! bbp_is_forum_public( $forum_id, false )
		) );

		// Add the activity entry ID as a meta value to the topic
		if ( !empty( $activity_id ) ) {
			update_post_meta( $topic_id, '_bbp_activity_id', $activity_id );
		}
	}