bp_media_forums_new_post_media_save( $post_id )

function bp_media_forums_new_post_media_save( $post_id ) {

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

		// save activity id if it is saved in forums and enabled in platform settings
		$main_activity_id = get_post_meta( $post_id, '_bbp_activity_id', true );

		// save media
		$medias = json_decode( stripslashes( $_POST['bbp_media'] ), true );

		//fetch currently uploaded media ids
		$existing_media                = [];
		$existing_media_ids            = get_post_meta( $post_id, 'bp_media_ids', true );
		$existing_media_attachment_ids = array();
		if ( ! empty( $existing_media_ids ) ) {
			$existing_media_ids = explode( ',', $existing_media_ids );

			foreach ( $existing_media_ids as $existing_media_id ) {
				$existing_media[ $existing_media_id ] = new BP_Media( $existing_media_id );

				if ( ! empty( $existing_media[ $existing_media_id ]->attachment_id ) ) {
					$existing_media_attachment_ids[] = $existing_media[ $existing_media_id ]->attachment_id;
				}
			}
		}

		$media_ids = array();
		foreach ( $medias as $media ) {

			$title             = ! empty( $media['name'] ) ? $media['name'] : '';
			$attachment_id     = ! empty( $media['id'] ) ? $media['id'] : 0;
			$attached_media_id = ! empty( $media['media_id'] ) ? $media['media_id'] : 0;
			$album_id          = ! empty( $media['album_id'] ) ? $media['album_id'] : 0;
			$group_id          = ! empty( $media['group_id'] ) ? $media['group_id'] : 0;
			$menu_order        = ! empty( $media['menu_order'] ) ? $media['menu_order'] : 0;

			if ( ! empty( $existing_media_attachment_ids ) ) {
				$index = array_search( $attachment_id, $existing_media_attachment_ids );
				if ( ! empty( $attachment_id ) && $index !== false && ! empty( $existing_media[ $attached_media_id ] ) ) {

					$existing_media[ $attached_media_id ]->menu_order = $menu_order;
					$existing_media[ $attached_media_id ]->save();

					unset( $existing_media_ids[ $index ] );
					$media_ids[] = $attached_media_id;
					continue;
				}
			}

			$media_id = bp_media_add( array(
				'attachment_id' => $attachment_id,
				'title'         => $title,
				'album_id'      => $album_id,
				'group_id'      => $group_id,
				'error_type'    => 'wp_error'
			) );

			if ( ! is_wp_error( $media_id ) ) {
				$media_ids[] = $media_id;

				//save media is saved in attachment
				update_post_meta( $attachment_id, 'bp_media_saved', true );
			}
		}

		$media_ids = implode( ',', $media_ids );

		//Save all attachment ids in forums post meta
		update_post_meta( $post_id, 'bp_media_ids', $media_ids );

		//save media meta for activity
		if ( ! empty( $main_activity_id ) && bp_is_active( 'activity' ) ) {
			bp_activity_update_meta( $main_activity_id, 'bp_media_ids', $media_ids );
		}

		// delete medias which were not saved or removed from form
		if ( ! empty( $existing_media_ids ) ) {
            foreach ( $existing_media_ids as $media_id ) {
                bp_media_delete( $media_id );
            }
		}
	}
}