public function calculate_shipping( $packages = array() ) {
		$this->packages = array();

		if ( ! $this->enabled || empty( $packages ) ) {
			return array();
		}

		// Calculate costs for passed packages.
		foreach ( $packages as $package_key => $package ) {
			$this->packages[ $package_key ] = $this->calculate_shipping_for_package( $package, $package_key );
		}

		/**
		 * Allow packages to be reorganized after calculating the shipping.
		 *
		 * This filter can be used to apply some extra manipulation after the shipping costs are calculated for the packages
		 * but before WooCommerce does anything with them. A good example of usage is to merge the shipping methods for multiple
		 * packages for marketplaces.
		 *
		 * @since 2.6.0
		 *
		 * @param array $packages The array of packages after shipping costs are calculated.
		 */
		$this->packages = array_filter( (array) apply_filters( 'woocommerce_shipping_packages', $this->packages ) );

		return $this->packages;
	}