public static function before_delete_order( $order_id ) {
		if ( in_array( get_post_type( $order_id ), wc_get_order_types(), true ) ) {
			// Clean up user.
			$order = wc_get_order( $order_id );

			// Check for `get_customer_id`, since this may be e.g. a refund order (which doesn't implement it).
			$customer_id = is_callable( array( $order, 'get_customer_id' ) ) ? $order->get_customer_id() : 0;

			if ( $customer_id > 0 && 'shop_order' === $order->get_type() ) {
				$customer    = new WC_Customer( $customer_id );
				$order_count = $customer->get_order_count();
				$order_count --;

				if ( 0 === $order_count ) {
					$customer->set_is_paying_customer( false );
					$customer->save();
				}

				// Delete order count meta.
				delete_user_meta( $customer_id, '_order_count' );
			}

			// Clean up items.
			self::delete_order_items( $order_id );
			self::delete_order_downloadable_permissions( $order_id );
		}
	}