bp_activity_create_parent_media_activity( $media_ids )

function bp_activity_create_parent_media_activity( $media_ids ) {
	global $bp_media_upload_count;

	if ( ! empty( $media_ids ) && ! isset( $_POST['bp_activity_update'] ) ) {

		$added_media_ids = $media_ids;
		$content         = false;

		if ( ! empty( $_POST['content'] ) ) {

			/**
			 * Filters the content provided in the activity input field.
			 *
			 * @param string $value Activity message being posted.
			 *
			 * @since BuddyPress 1.2.0
			 *
			 */
			$content = apply_filters( 'bp_activity_post_update_content', $_POST['content'] );
		}

		$group_id = FILTER_INPUT( INPUT_POST, 'group_id', FILTER_SANITIZE_NUMBER_INT );
		$album_id = false;

		if ( bp_is_active( 'groups' ) && ! empty( $group_id ) && $group_id > 0 ) {
			$activity_id = groups_post_update( array( 'content' => $content, 'group_id' => $group_id ) );
		} else {
			$activity_id = bp_activity_post_update( array( 'content' => $content ) );
		}

		//save media meta for activity
		if ( ! empty( $activity_id ) ) {
			$privacy = 'public';

			foreach ( (array) $added_media_ids as $media_id ) {
				$media = new BP_Media( $media_id );

				// get one of the media's privacy for the activity privacy
				$privacy = $media->privacy;

				// get media album id
				if ( ! empty( $media->album_id ) ) {
					$album_id = $media->album_id;
				}

				if ( 1 === $bp_media_upload_count ) {
					//save media activity id in media
					$media->activity_id = $activity_id;
					$media->save();
				}

				//save parent activity id in attachment meta
				update_post_meta( $media->attachment_id, 'bp_media_parent_activity_id', $activity_id );
			}

			bp_activity_update_meta( $activity_id, 'bp_media_ids', implode( ',', $added_media_ids ) );

			// if media is from album then save album id in activity media
			if ( ! empty( $album_id ) ) {
				bp_activity_update_meta( $activity_id, 'bp_media_album_activity', $album_id );
			}

			if ( empty( $group_id ) ) {
				$main_activity = new BP_Activity_Activity( $activity_id );
				if ( ! empty( $main_activity ) ) {
					$main_activity->privacy = $privacy;
					$main_activity->save();
				}
			}
		}
	}

	return $media_ids;
}