1. The name of an email template; 2. Email address; 3. User-agent that requested the action.
			esc_html__( 'Email template "%1$s" sent to %2$s, via %3$s.', 'woocommerce' ),
			esc_html( $template->get_title() ),
			esc_html( $order->get_billing_email() ),
			$user_agent ? $user_agent : 'REST API'
		);

		$messages = array_filter( $messages );
		foreach ( $messages as $message ) {
			$order->add_order_note( $message, false, true );
		}

		return array(
			'message' => implode( ' ', $messages ),
		);
	}

	/**
	 * Handle the POST /orders/{id}/actions/send_order_details.
	 *
	 * @param WP_REST_Request $request The received request.
	 * @return array|WP_Error Request response or an error.
	 */
	protected function send_order_details( WP_REST_Request $request ) {
		$order    = wc_get_order( $request->get_param( 'id' ) );
		$email    = $request->get_param( 'email' );
		$force    = wp_validate_boolean( $request->get_param( 'force_email_update' ) );
		$messages = array();

		if ( $email ) {
			$message = $this->maybe_update_billing_email( $order, $email, $force );
			if ( is_wp_error( $message ) ) {
				return $message;
			}
			$messages[] = $message;
		}

		if ( ! is_email( $order->get_billing_email() ) ) {
			return new WP_Error(
				'woocommerce_rest_missing_email',
				__( 'Order does not have an email address.', 'woocommerce' ),
				array( 'status' => 400 )
			);
		}

		// phpcs:disable WooCommerce.Commenting.CommentHooks.MissingSinceComment
		/** This action is documented in includes/admin/meta-boxes/class-wc-meta-box-order-actions.php */
		do_action( 'woocommerce_before_resend_order_emails', $order, 'customer_invoice' );

		WC()->payment_gateways();
		WC()->shipping();
		WC()->mailer()->customer_invoice( $order );

		$user_agent = esc_html( $request->get_header( 'User-Agent' ) );
		$messages[] = sprintf(
			// translators: %1$s is the customer email, %2$s is the user agent that requested the action.
			esc_html__( 'Order details sent to %1$s, via %2$s.', 'woocommerce' ),
			esc_html( $order->get_billing_email() ),
			$user_agent ? $user_agent : 'REST API'
		);

		$messages = array_filter( $messages );
		foreach ( $messages as $message ) {
			$order->add_order_note( $message, false, true );
		}

		// phpcs:disable WooCommerce.Commenting.CommentHooks.MissingSinceComment
		/** This action is documented in includes/admin/meta-boxes/class-wc-meta-box-order-actions.php */
		do_action( 'woocommerce_after_resend_order_email', $order, 'customer_invoice' );

		return array(
			'message' => implode( ' ', $messages ),
		);
	}

	/**
	 * Update the billing email of an order when certain conditions are met.
	 *
	 * If the order does not already have a billing email, it will be updated. If it does have one, but `$force` is set
	 * to `true`, it will be updated. Otherwise this will return an error. This can also return an error if the given
	 * email address is not valid.
	 *
	 * @param WC_Order $order The order to update.
	 * @param string   $email The email address to maybe add to the order.
	 * @param bool     $force Optional. True to update the order even if it already has a billing email. Default false.
	 *
	 * @return string|WP_Error A message upon success, otherwise an error.
	 */
	private function maybe_update_billing_email( WC_Order $order, string $email, ?bool $force = false ) {
		$existing_email = $order->get_billing_email( 'edit' );

		if ( $existing_email === $email ) {
			return '';
		}

		if ( $existing_email && true !== $force ) {
			return new WP_Error(
				'woocommerce_rest_order_billing_email_exists',
				__( 'Order already has a billing email.', 'woocommerce' ),
				array( 'status' => 400 )
			);
		}

		try {
			$order->set_billing_email( $email );
			$order->save();
		} catch ( WC_Data_Exception $e ) {
			return new WP_Error(
				$e->getErrorCode(),
				$e->getMessage()
			);
		}

		return sprintf(
			// translators: %s is an email address.
			__( 'Billing email updated to %s.', 'woocommerce' ),
			esc_html( $email )
		);
	}

	/**
	 * Check if a given order has any partial refunds.
	 *
	 * Based on heuristics in the `wc_create_refund()` function.
	 *
	 * @param WC_Order $order An order object.
	 *
	 * @return bool
	 */
	private function order_is_partially_refunded( WC_Order $order ): bool {
		$remaining_amount = $order->get_remaining_refund_amount();
		$remaining_items  = $order->get_remaining_refund_items();
		$refunds          = $order->get_refunds();
		$last_refund      = reset( $refunds );

		// phpcs:disable WooCommerce.Commenting.CommentHooks.MissingSinceComment
		/** This filter is documented in includes/wc-order-functions.php */
		$partially_refunded = apply_filters(
			'woocommerce_order_is_partially_refunded',
			count( $refunds ) > 0 && ( $remaining_amount > 0 || ( $order->has_free_item() && $remaining_items > 0 ) ),
			$order->get_id(),
			$last_refund ? $last_refund->get_id() : 0
		);

		return (bool) $partially_refunded;
	}
}