brandon14/ebay-sdk-php

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src/Buy/Order/V2/Api/GuestCheckoutSessionApi.php

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<?php

/**
 * This file is part of the trollandtoad/ebay-sdk-php package.
 *
 * MIT License
 *
 * Copyright (c) 2022 Brandon Clothier
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

declare(strict_types=1);

/**
 * GuestCheckoutSessionApi.
 *
 * PHP version ^7.2 || ^8.0
 *
 * @category Class
 *
 * @author   OpenAPI Generator team
 *
 * @see     https://openapi-generator.tech
 */

/**
 * Order API.
 *
 * <span class=\"tablenote\"><b>Note:</b> The Order API (v2) currently only supports the guest payment/checkout flow. If you need to support member payment/checkout flow, use the <a href=\"/api-docs/buy/order_v1/resources/methods\">v1_beta version</a> of the Order API.</span><br /><br /><span class=\"tablenote\"><b>Note:</b> This is a <a href=\"https://developer.ebay.com/api-docs/static/versioning.html#limited\" target=\"_blank\"><img src=\"/cms/img/docs/partners-api.svg\" class=\"legend-icon partners-icon\"  alt=\"Limited Release\" title=\"Limited Release\" />(Limited Release)</a> API available only to select developers approved by business units.</span><br /><br />The Order API provides interfaces that let shoppers pay for items. It also returns payment and shipping status of the order.
 *
 * The version of the OpenAPI document: v2.1.0
 * Generated by: https://openapi-generator.tech
 * OpenAPI Generator version: 5.4.0
 */

/**
 * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
 * https://openapi-generator.tech
 * Do not edit the class manually.
 */

namespace TNT\Ebay\Buy\Order\V2\Api;

use GuzzleHttp\Client;
use GuzzleHttp\Psr7\Request;
use GuzzleHttp\RequestOptions;
use GuzzleHttp\ClientInterface;
use GuzzleHttp\Psr7\MultipartStream;
use TNT\Ebay\Buy\Order\V2\ApiException;
use TNT\Ebay\Buy\Order\V2\Configuration;
use GuzzleHttp\Exception\GuzzleException;
use TNT\Ebay\Buy\Order\V2\HeaderSelector;
use GuzzleHttp\Exception\ConnectException;
use GuzzleHttp\Exception\RequestException;
use TNT\Ebay\Buy\Order\V2\ObjectSerializer;

/**
 * GuestCheckoutSessionApi Class Doc Comment.
 *
 * @category Class
 *
 * @author   OpenAPI Generator team
 *
 * @see     https://openapi-generator.tech
 */
class GuestCheckoutSessionApi
{
    /**
     * @var ClientInterface
     */
    protected $client;

    /**
     * @var Configuration
     */
    protected $config;

    /**
     * @var HeaderSelector
     */
    protected $headerSelector;

    /**
     * @var int Host index
     */
    protected $hostIndex;

    /**
     * @param ClientInterface $client
     * @param Configuration   $config
     * @param HeaderSelector  $selector
     * @param int             $hostIndex (Optional) host index to select the list of hosts if defined in the OpenAPI spec
     */
    public function __construct(
        ClientInterface $client = null,
        Configuration $config = null,
        HeaderSelector $selector = null,
        $hostIndex = 0
    ) {
        $this->client = $client ?: new Client();
        $this->config = $config ?: new Configuration();
        $this->headerSelector = $selector ?: new HeaderSelector();
        $this->hostIndex = $hostIndex;
    }

    /**
     * Set the host index.
     *
     * @param int $hostIndex Host index (required)
     */
    public function setHostIndex($hostIndex): void
    {
        $this->hostIndex = $hostIndex;
    }

    /**
     * Get the host index.
     *
     * @return int Host index
     */
    public function getHostIndex()
    {
        return $this->hostIndex;
    }

    /**
     * @return Configuration
     */
    public function getConfiguration()
    {
        return $this->config;
    }

    /**
     * Operation applyGuestCoupon.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used to apply a coupon to a guest checkout session. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2
     */
    public function applyGuestCoupon($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        [$response] = $this->applyGuestCouponWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request);

        return $response;
    }

    /**
     * Operation applyGuestCouponWithHttpInfo.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used to apply a coupon to a guest checkout session. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return array of \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2, HTTP status code, HTTP response headers (array of strings)
     */
    public function applyGuestCouponWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        $request = $this->applyGuestCouponRequest($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request);

        try {
            $options = $this->createHttpClientOption();

            try {
                $response = $this->client->send($request, $options);
            } catch (RequestException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), $e->getResponse() ? $e->getResponse()->getHeaders() : null, $e->getResponse() ? (string) $e->getResponse()->getBody() : null, $e);
            } catch (ConnectException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            } catch (GuzzleException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            }

            $statusCode = $response->getStatusCode();

            if ($statusCode < 200 || $statusCode > 299) {
                throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, (string) $request->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody());
            }

            switch ($statusCode) {
                case 200:
                    if ('\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2' === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2', []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
            }

            $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';

            if ($returnType === '\SplFileObject') {
                $content = $response->getBody(); // Stream goes to serializer.
            } else {
                $content = (string) $response->getBody();
            }

            return [
                ObjectSerializer::deserialize($content, $returnType, []),
                $response->getStatusCode(),
                $response->getHeaders(),
            ];
        } catch (ApiException $e) {
            switch ($e->getCode()) {
                case 200:
                    $data = ObjectSerializer::deserialize(
                        $e->getResponseBody(),
                        '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2',
                        $e->getResponseHeaders()
                    );
                    $e->setResponseObject($data);
                    break;
            }

            throw $e;
        }
    }

    /**
     * Operation applyGuestCouponAsync.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used to apply a coupon to a guest checkout session. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function applyGuestCouponAsync($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        return $this->applyGuestCouponAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }

    /**
     * Operation applyGuestCouponAsyncWithHttpInfo.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used to apply a coupon to a guest checkout session. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function applyGuestCouponAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';
        $request = $this->applyGuestCouponRequest($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request);

        return $this->client
            ->sendAsync($request, $this->createHttpClientOption())
            ->then(
                function ($response) use ($returnType) {
                    if ($returnType === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, $returnType, []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
                },
                function ($exception) {
                    $response = $exception->getResponse();
                    $statusCode = $response->getStatusCode();

                    throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, $exception->getRequest()->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody(), $exception instanceof \Throwable ? $exception : null);
                }
            );
    }

    /**
     * Create request for operation 'applyGuestCoupon'.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used to apply a coupon to a guest checkout session. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Psr7\Request
     */
    public function applyGuestCouponRequest($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        // Verify the required parameter 'checkout_session_id' is set.
        if ($checkout_session_id === null || (\is_array($checkout_session_id) && count($checkout_session_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $checkout_session_id when calling applyGuestCoupon');
        }
        // Verify the required parameter 'x_ebay_c_marketplace_id' is set.
        if ($x_ebay_c_marketplace_id === null || (\is_array($x_ebay_c_marketplace_id) && count($x_ebay_c_marketplace_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $x_ebay_c_marketplace_id when calling applyGuestCoupon');
        }

        $resourcePath = '/guest_checkout_session/{checkoutSessionId}/apply_coupon';
        $formParams = [];
        $queryParams = [];
        $headerParams = [];
        $httpBody = '';
        $multipart = false;

        // header params
        if ($x_ebay_c_marketplace_id !== null) {
            $headerParams['X-EBAY-C-MARKETPLACE-ID'] = ObjectSerializer::toHeaderValue($x_ebay_c_marketplace_id);
        }

        // path params
        if ($checkout_session_id !== null) {
            $resourcePath = str_replace(
                '{checkoutSessionId}',
                ObjectSerializer::toPathValue($checkout_session_id),
                $resourcePath
            );
        }

        if ($multipart) {
            $headers = $this->headerSelector->selectHeadersForMultipart(
                ['application/json']
            );
        } else {
            $headers = $this->headerSelector->selectHeaders(
                ['application/json'],
                ['application/json']
            );
        }

        // For model (json/xml)
        if (isset($coupon_request)) {
            if ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode(ObjectSerializer::sanitizeForSerialization($coupon_request));
            } else {
                $httpBody = $coupon_request;
            }
        } elseif (count($formParams) > 0) {
            if ($multipart) {
                $multipartContents = [];

                foreach ($formParams as $formParamName => $formParamValue) {
                    $formParamValueItems = is_array($formParamValue) ? $formParamValue : [$formParamValue];
                    foreach ($formParamValueItems as $formParamValueItem) {
                        $multipartContents[] = [
                            'name' => $formParamName,
                            'contents' => $formParamValueItem,
                        ];
                    }
                }

                // For HTTP post (form)
                $httpBody = new MultipartStream($multipartContents);
            } elseif ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode($formParams);
            } else {
                // For HTTP post (form)
                $httpBody = ObjectSerializer::buildQuery($queryParams);
            }
        }

        // this endpoint requires OAuth (access token)
        if (! empty($this->config->getAccessToken())) {
            $headers['Authorization'] = 'Bearer '.$this->config->getAccessToken();
        }

        $defaultHeaders = [];
        if ($this->config->getUserAgent()) {
            $defaultHeaders['User-Agent'] = $this->config->getUserAgent();
        }

        $headers = array_merge(
            $defaultHeaders,
            $headerParams,
            $headers
        );

        $query = ObjectSerializer::buildQuery($queryParams);

        return new Request(
            'POST',
            $this->config->getHost().$resourcePath.($query ? "?{$query}" : ''),
            $headers,
            $httpBody
        );
    }

    /**
     * Operation getGuestCheckoutSession.
     *
     * @param string $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2
     */
    public function getGuestCheckoutSession($checkout_session_id, $x_ebay_c_marketplace_id)
    {
        [$response] = $this->getGuestCheckoutSessionWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id);

        return $response;
    }

    /**
     * Operation getGuestCheckoutSessionWithHttpInfo.
     *
     * @param string $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return array of \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2, HTTP status code, HTTP response headers (array of strings)
     */
    public function getGuestCheckoutSessionWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id)
    {
        $request = $this->getGuestCheckoutSessionRequest($checkout_session_id, $x_ebay_c_marketplace_id);

        try {
            $options = $this->createHttpClientOption();

            try {
                $response = $this->client->send($request, $options);
            } catch (RequestException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), $e->getResponse() ? $e->getResponse()->getHeaders() : null, $e->getResponse() ? (string) $e->getResponse()->getBody() : null, $e);
            } catch (ConnectException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            } catch (GuzzleException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            }

            $statusCode = $response->getStatusCode();

            if ($statusCode < 200 || $statusCode > 299) {
                throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, (string) $request->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody());
            }

            switch ($statusCode) {
                case 200:
                    if ('\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2' === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2', []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
            }

            $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';

            if ($returnType === '\SplFileObject') {
                $content = $response->getBody(); // Stream goes to serializer.
            } else {
                $content = (string) $response->getBody();
            }

            return [
                ObjectSerializer::deserialize($content, $returnType, []),
                $response->getStatusCode(),
                $response->getHeaders(),
            ];
        } catch (ApiException $e) {
            switch ($e->getCode()) {
                case 200:
                    $data = ObjectSerializer::deserialize(
                        $e->getResponseBody(),
                        '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2',
                        $e->getResponseHeaders()
                    );
                    $e->setResponseObject($data);
                    break;
            }

            throw $e;
        }
    }

    /**
     * Operation getGuestCheckoutSessionAsync.
     *
     * @param string $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function getGuestCheckoutSessionAsync($checkout_session_id, $x_ebay_c_marketplace_id)
    {
        return $this->getGuestCheckoutSessionAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }

    /**
     * Operation getGuestCheckoutSessionAsyncWithHttpInfo.
     *
     * @param string $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function getGuestCheckoutSessionAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id)
    {
        $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';
        $request = $this->getGuestCheckoutSessionRequest($checkout_session_id, $x_ebay_c_marketplace_id);

        return $this->client
            ->sendAsync($request, $this->createHttpClientOption())
            ->then(
                function ($response) use ($returnType) {
                    if ($returnType === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, $returnType, []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
                },
                function ($exception) {
                    $response = $exception->getResponse();
                    $statusCode = $response->getStatusCode();

                    throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, $exception->getRequest()->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody(), $exception instanceof \Throwable ? $exception : null);
                }
            );
    }

    /**
     * Create request for operation 'getGuestCheckoutSession'.
     *
     * @param string $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Psr7\Request
     */
    public function getGuestCheckoutSessionRequest($checkout_session_id, $x_ebay_c_marketplace_id)
    {
        // Verify the required parameter 'checkout_session_id' is set.
        if ($checkout_session_id === null || (\is_array($checkout_session_id) && count($checkout_session_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $checkout_session_id when calling getGuestCheckoutSession');
        }
        // Verify the required parameter 'x_ebay_c_marketplace_id' is set.
        if ($x_ebay_c_marketplace_id === null || (\is_array($x_ebay_c_marketplace_id) && count($x_ebay_c_marketplace_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $x_ebay_c_marketplace_id when calling getGuestCheckoutSession');
        }

        $resourcePath = '/guest_checkout_session/{checkoutSessionId}';
        $formParams = [];
        $queryParams = [];
        $headerParams = [];
        $httpBody = '';
        $multipart = false;

        // header params
        if ($x_ebay_c_marketplace_id !== null) {
            $headerParams['X-EBAY-C-MARKETPLACE-ID'] = ObjectSerializer::toHeaderValue($x_ebay_c_marketplace_id);
        }

        // path params
        if ($checkout_session_id !== null) {
            $resourcePath = str_replace(
                '{checkoutSessionId}',
                ObjectSerializer::toPathValue($checkout_session_id),
                $resourcePath
            );
        }

        if ($multipart) {
            $headers = $this->headerSelector->selectHeadersForMultipart(
                ['application/json']
            );
        } else {
            $headers = $this->headerSelector->selectHeaders(
                ['application/json'],
                []
            );
        }

        // For model (json/xml)
        if (count($formParams) > 0) {
            if ($multipart) {
                $multipartContents = [];

                foreach ($formParams as $formParamName => $formParamValue) {
                    $formParamValueItems = is_array($formParamValue) ? $formParamValue : [$formParamValue];
                    foreach ($formParamValueItems as $formParamValueItem) {
                        $multipartContents[] = [
                            'name' => $formParamName,
                            'contents' => $formParamValueItem,
                        ];
                    }
                }

                // For HTTP post (form)
                $httpBody = new MultipartStream($multipartContents);
            } elseif ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode($formParams);
            } else {
                // For HTTP post (form)
                $httpBody = ObjectSerializer::buildQuery($queryParams);
            }
        }

        // this endpoint requires OAuth (access token)
        if (! empty($this->config->getAccessToken())) {
            $headers['Authorization'] = 'Bearer '.$this->config->getAccessToken();
        }

        $defaultHeaders = [];
        if ($this->config->getUserAgent()) {
            $defaultHeaders['User-Agent'] = $this->config->getUserAgent();
        }

        $headers = array_merge(
            $defaultHeaders,
            $headerParams,
            $headers
        );

        $query = ObjectSerializer::buildQuery($queryParams);

        return new Request(
            'GET',
            $this->config->getHost().$resourcePath.($query ? "?{$query}" : ''),
            $headers,
            $httpBody
        );
    }

    /**
     * Operation initiateGuestCheckoutSession.
     *
     * @param string                                                           $x_ebay_c_marketplace_id                  A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param string                                                           $x_ebay_c_enduserctx                      A header that is used to specify the &lt;b&gt;affiliateCampaignId&lt;/b&gt;, and optionally the &lt;b&gt;affiliateReferenceId&lt;/b&gt;, to enable revenue sharing when the buyer purchases items.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;font color&#x3D;\&quot;006600\&quot;&gt;&lt;b&gt;TIP:&lt;/b&gt;&lt;/font&gt; See &lt;a href&#x3D;\&quot;/api-docs/buy/static/api-browse.html#Headers\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Request headers&lt;/a&gt; in the Buying Integration Guide for more information.&lt;/span&gt; (optional)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CreateGuestCheckoutSessionRequestV2 $create_guest_checkout_session_request_v2 The container for the fields used by the &lt;b&gt;initiateGuestCheckoutSession&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2
     */
    public function initiateGuestCheckoutSession($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx = null, $create_guest_checkout_session_request_v2 = null)
    {
        [$response] = $this->initiateGuestCheckoutSessionWithHttpInfo($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx, $create_guest_checkout_session_request_v2);

        return $response;
    }

    /**
     * Operation initiateGuestCheckoutSessionWithHttpInfo.
     *
     * @param string                                                           $x_ebay_c_marketplace_id                  A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param string                                                           $x_ebay_c_enduserctx                      A header that is used to specify the &lt;b&gt;affiliateCampaignId&lt;/b&gt;, and optionally the &lt;b&gt;affiliateReferenceId&lt;/b&gt;, to enable revenue sharing when the buyer purchases items.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;font color&#x3D;\&quot;006600\&quot;&gt;&lt;b&gt;TIP:&lt;/b&gt;&lt;/font&gt; See &lt;a href&#x3D;\&quot;/api-docs/buy/static/api-browse.html#Headers\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Request headers&lt;/a&gt; in the Buying Integration Guide for more information.&lt;/span&gt; (optional)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CreateGuestCheckoutSessionRequestV2 $create_guest_checkout_session_request_v2 The container for the fields used by the &lt;b&gt;initiateGuestCheckoutSession&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return array of \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2, HTTP status code, HTTP response headers (array of strings)
     */
    public function initiateGuestCheckoutSessionWithHttpInfo($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx = null, $create_guest_checkout_session_request_v2 = null)
    {
        $request = $this->initiateGuestCheckoutSessionRequest($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx, $create_guest_checkout_session_request_v2);

        try {
            $options = $this->createHttpClientOption();

            try {
                $response = $this->client->send($request, $options);
            } catch (RequestException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), $e->getResponse() ? $e->getResponse()->getHeaders() : null, $e->getResponse() ? (string) $e->getResponse()->getBody() : null, $e);
            } catch (ConnectException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            } catch (GuzzleException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            }

            $statusCode = $response->getStatusCode();

            if ($statusCode < 200 || $statusCode > 299) {
                throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, (string) $request->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody());
            }

            switch ($statusCode) {
                case 200:
                    if ('\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2' === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2', []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
            }

            $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';

            if ($returnType === '\SplFileObject') {
                $content = $response->getBody(); // Stream goes to serializer.
            } else {
                $content = (string) $response->getBody();
            }

            return [
                ObjectSerializer::deserialize($content, $returnType, []),
                $response->getStatusCode(),
                $response->getHeaders(),
            ];
        } catch (ApiException $e) {
            switch ($e->getCode()) {
                case 200:
                    $data = ObjectSerializer::deserialize(
                        $e->getResponseBody(),
                        '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2',
                        $e->getResponseHeaders()
                    );
                    $e->setResponseObject($data);
                    break;
            }

            throw $e;
        }
    }

    /**
     * Operation initiateGuestCheckoutSessionAsync.
     *
     * @param string                                                           $x_ebay_c_marketplace_id                  A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param string                                                           $x_ebay_c_enduserctx                      A header that is used to specify the &lt;b&gt;affiliateCampaignId&lt;/b&gt;, and optionally the &lt;b&gt;affiliateReferenceId&lt;/b&gt;, to enable revenue sharing when the buyer purchases items.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;font color&#x3D;\&quot;006600\&quot;&gt;&lt;b&gt;TIP:&lt;/b&gt;&lt;/font&gt; See &lt;a href&#x3D;\&quot;/api-docs/buy/static/api-browse.html#Headers\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Request headers&lt;/a&gt; in the Buying Integration Guide for more information.&lt;/span&gt; (optional)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CreateGuestCheckoutSessionRequestV2 $create_guest_checkout_session_request_v2 The container for the fields used by the &lt;b&gt;initiateGuestCheckoutSession&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function initiateGuestCheckoutSessionAsync($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx = null, $create_guest_checkout_session_request_v2 = null)
    {
        return $this->initiateGuestCheckoutSessionAsyncWithHttpInfo($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx, $create_guest_checkout_session_request_v2)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }

    /**
     * Operation initiateGuestCheckoutSessionAsyncWithHttpInfo.
     *
     * @param string                                                           $x_ebay_c_marketplace_id                  A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param string                                                           $x_ebay_c_enduserctx                      A header that is used to specify the &lt;b&gt;affiliateCampaignId&lt;/b&gt;, and optionally the &lt;b&gt;affiliateReferenceId&lt;/b&gt;, to enable revenue sharing when the buyer purchases items.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;font color&#x3D;\&quot;006600\&quot;&gt;&lt;b&gt;TIP:&lt;/b&gt;&lt;/font&gt; See &lt;a href&#x3D;\&quot;/api-docs/buy/static/api-browse.html#Headers\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Request headers&lt;/a&gt; in the Buying Integration Guide for more information.&lt;/span&gt; (optional)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CreateGuestCheckoutSessionRequestV2 $create_guest_checkout_session_request_v2 The container for the fields used by the &lt;b&gt;initiateGuestCheckoutSession&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function initiateGuestCheckoutSessionAsyncWithHttpInfo($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx = null, $create_guest_checkout_session_request_v2 = null)
    {
        $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';
        $request = $this->initiateGuestCheckoutSessionRequest($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx, $create_guest_checkout_session_request_v2);

        return $this->client
            ->sendAsync($request, $this->createHttpClientOption())
            ->then(
                function ($response) use ($returnType) {
                    if ($returnType === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, $returnType, []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
                },
                function ($exception) {
                    $response = $exception->getResponse();
                    $statusCode = $response->getStatusCode();

                    throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, $exception->getRequest()->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody(), $exception instanceof \Throwable ? $exception : null);
                }
            );
    }

    /**
     * Create request for operation 'initiateGuestCheckoutSession'.
     *
     * @param string                                                           $x_ebay_c_marketplace_id                  A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param string                                                           $x_ebay_c_enduserctx                      A header that is used to specify the &lt;b&gt;affiliateCampaignId&lt;/b&gt;, and optionally the &lt;b&gt;affiliateReferenceId&lt;/b&gt;, to enable revenue sharing when the buyer purchases items.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;font color&#x3D;\&quot;006600\&quot;&gt;&lt;b&gt;TIP:&lt;/b&gt;&lt;/font&gt; See &lt;a href&#x3D;\&quot;/api-docs/buy/static/api-browse.html#Headers\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Request headers&lt;/a&gt; in the Buying Integration Guide for more information.&lt;/span&gt; (optional)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CreateGuestCheckoutSessionRequestV2 $create_guest_checkout_session_request_v2 The container for the fields used by the &lt;b&gt;initiateGuestCheckoutSession&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Psr7\Request
     */
    public function initiateGuestCheckoutSessionRequest($x_ebay_c_marketplace_id, $x_ebay_c_enduserctx = null, $create_guest_checkout_session_request_v2 = null)
    {
        // Verify the required parameter 'x_ebay_c_marketplace_id' is set.
        if ($x_ebay_c_marketplace_id === null || (\is_array($x_ebay_c_marketplace_id) && count($x_ebay_c_marketplace_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $x_ebay_c_marketplace_id when calling initiateGuestCheckoutSession');
        }

        $resourcePath = '/guest_checkout_session/initiate';
        $formParams = [];
        $queryParams = [];
        $headerParams = [];
        $httpBody = '';
        $multipart = false;

        // header params
        if ($x_ebay_c_enduserctx !== null) {
            $headerParams['X-EBAY-C-ENDUSERCTX'] = ObjectSerializer::toHeaderValue($x_ebay_c_enduserctx);
        }
        // header params
        if ($x_ebay_c_marketplace_id !== null) {
            $headerParams['X-EBAY-C-MARKETPLACE-ID'] = ObjectSerializer::toHeaderValue($x_ebay_c_marketplace_id);
        }

        if ($multipart) {
            $headers = $this->headerSelector->selectHeadersForMultipart(
                ['application/json']
            );
        } else {
            $headers = $this->headerSelector->selectHeaders(
                ['application/json'],
                ['application/json']
            );
        }

        // For model (json/xml)
        if (isset($create_guest_checkout_session_request_v2)) {
            if ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode(ObjectSerializer::sanitizeForSerialization($create_guest_checkout_session_request_v2));
            } else {
                $httpBody = $create_guest_checkout_session_request_v2;
            }
        } elseif (count($formParams) > 0) {
            if ($multipart) {
                $multipartContents = [];

                foreach ($formParams as $formParamName => $formParamValue) {
                    $formParamValueItems = is_array($formParamValue) ? $formParamValue : [$formParamValue];
                    foreach ($formParamValueItems as $formParamValueItem) {
                        $multipartContents[] = [
                            'name' => $formParamName,
                            'contents' => $formParamValueItem,
                        ];
                    }
                }

                // For HTTP post (form)
                $httpBody = new MultipartStream($multipartContents);
            } elseif ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode($formParams);
            } else {
                // For HTTP post (form)
                $httpBody = ObjectSerializer::buildQuery($queryParams);
            }
        }

        // this endpoint requires OAuth (access token)
        if (! empty($this->config->getAccessToken())) {
            $headers['Authorization'] = 'Bearer '.$this->config->getAccessToken();
        }

        $defaultHeaders = [];
        if ($this->config->getUserAgent()) {
            $defaultHeaders['User-Agent'] = $this->config->getUserAgent();
        }

        $headers = array_merge(
            $defaultHeaders,
            $headerParams,
            $headers
        );

        $query = ObjectSerializer::buildQuery($queryParams);

        return new Request(
            'POST',
            $this->config->getHost().$resourcePath.($query ? "?{$query}" : ''),
            $headers,
            $httpBody
        );
    }

    /**
     * Operation removeGuestCoupon.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used by the &lt;b&gt;removeGuestCoupon&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2
     */
    public function removeGuestCoupon($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        [$response] = $this->removeGuestCouponWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request);

        return $response;
    }

    /**
     * Operation removeGuestCouponWithHttpInfo.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used by the &lt;b&gt;removeGuestCoupon&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return array of \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2, HTTP status code, HTTP response headers (array of strings)
     */
    public function removeGuestCouponWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        $request = $this->removeGuestCouponRequest($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request);

        try {
            $options = $this->createHttpClientOption();

            try {
                $response = $this->client->send($request, $options);
            } catch (RequestException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), $e->getResponse() ? $e->getResponse()->getHeaders() : null, $e->getResponse() ? (string) $e->getResponse()->getBody() : null, $e);
            } catch (ConnectException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            } catch (GuzzleException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            }

            $statusCode = $response->getStatusCode();

            if ($statusCode < 200 || $statusCode > 299) {
                throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, (string) $request->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody());
            }

            switch ($statusCode) {
                case 200:
                    if ('\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2' === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2', []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
            }

            $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';

            if ($returnType === '\SplFileObject') {
                $content = $response->getBody(); // Stream goes to serializer.
            } else {
                $content = (string) $response->getBody();
            }

            return [
                ObjectSerializer::deserialize($content, $returnType, []),
                $response->getStatusCode(),
                $response->getHeaders(),
            ];
        } catch (ApiException $e) {
            switch ($e->getCode()) {
                case 200:
                    $data = ObjectSerializer::deserialize(
                        $e->getResponseBody(),
                        '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2',
                        $e->getResponseHeaders()
                    );
                    $e->setResponseObject($data);
                    break;
            }

            throw $e;
        }
    }

    /**
     * Operation removeGuestCouponAsync.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used by the &lt;b&gt;removeGuestCoupon&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function removeGuestCouponAsync($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        return $this->removeGuestCouponAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }

    /**
     * Operation removeGuestCouponAsyncWithHttpInfo.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used by the &lt;b&gt;removeGuestCoupon&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function removeGuestCouponAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';
        $request = $this->removeGuestCouponRequest($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request);

        return $this->client
            ->sendAsync($request, $this->createHttpClientOption())
            ->then(
                function ($response) use ($returnType) {
                    if ($returnType === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, $returnType, []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
                },
                function ($exception) {
                    $response = $exception->getResponse();
                    $statusCode = $response->getStatusCode();

                    throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, $exception->getRequest()->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody(), $exception instanceof \Throwable ? $exception : null);
                }
            );
    }

    /**
     * Create request for operation 'removeGuestCoupon'.
     *
     * @param string                                     $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                     $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\CouponRequest $coupon_request          The container for the fields used by the &lt;b&gt;removeGuestCoupon&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Psr7\Request
     */
    public function removeGuestCouponRequest($checkout_session_id, $x_ebay_c_marketplace_id, $coupon_request = null)
    {
        // Verify the required parameter 'checkout_session_id' is set.
        if ($checkout_session_id === null || (\is_array($checkout_session_id) && count($checkout_session_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $checkout_session_id when calling removeGuestCoupon');
        }
        // Verify the required parameter 'x_ebay_c_marketplace_id' is set.
        if ($x_ebay_c_marketplace_id === null || (\is_array($x_ebay_c_marketplace_id) && count($x_ebay_c_marketplace_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $x_ebay_c_marketplace_id when calling removeGuestCoupon');
        }

        $resourcePath = '/guest_checkout_session/{checkoutSessionId}/remove_coupon';
        $formParams = [];
        $queryParams = [];
        $headerParams = [];
        $httpBody = '';
        $multipart = false;

        // header params
        if ($x_ebay_c_marketplace_id !== null) {
            $headerParams['X-EBAY-C-MARKETPLACE-ID'] = ObjectSerializer::toHeaderValue($x_ebay_c_marketplace_id);
        }

        // path params
        if ($checkout_session_id !== null) {
            $resourcePath = str_replace(
                '{checkoutSessionId}',
                ObjectSerializer::toPathValue($checkout_session_id),
                $resourcePath
            );
        }

        if ($multipart) {
            $headers = $this->headerSelector->selectHeadersForMultipart(
                ['application/json']
            );
        } else {
            $headers = $this->headerSelector->selectHeaders(
                ['application/json'],
                ['application/json']
            );
        }

        // For model (json/xml)
        if (isset($coupon_request)) {
            if ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode(ObjectSerializer::sanitizeForSerialization($coupon_request));
            } else {
                $httpBody = $coupon_request;
            }
        } elseif (count($formParams) > 0) {
            if ($multipart) {
                $multipartContents = [];

                foreach ($formParams as $formParamName => $formParamValue) {
                    $formParamValueItems = is_array($formParamValue) ? $formParamValue : [$formParamValue];
                    foreach ($formParamValueItems as $formParamValueItem) {
                        $multipartContents[] = [
                            'name' => $formParamName,
                            'contents' => $formParamValueItem,
                        ];
                    }
                }

                // For HTTP post (form)
                $httpBody = new MultipartStream($multipartContents);
            } elseif ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode($formParams);
            } else {
                // For HTTP post (form)
                $httpBody = ObjectSerializer::buildQuery($queryParams);
            }
        }

        // this endpoint requires OAuth (access token)
        if (! empty($this->config->getAccessToken())) {
            $headers['Authorization'] = 'Bearer '.$this->config->getAccessToken();
        }

        $defaultHeaders = [];
        if ($this->config->getUserAgent()) {
            $defaultHeaders['User-Agent'] = $this->config->getUserAgent();
        }

        $headers = array_merge(
            $defaultHeaders,
            $headerParams,
            $headers
        );

        $query = ObjectSerializer::buildQuery($queryParams);

        return new Request(
            'POST',
            $this->config->getHost().$resourcePath.($query ? "?{$query}" : ''),
            $headers,
            $httpBody
        );
    }

    /**
     * Operation updateGuestQuantity.
     *
     * @param string                                      $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                      $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateQuantity $update_quantity         The container for the fields used by the &lt;b&gt;updateGuestQuantity&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2
     */
    public function updateGuestQuantity($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity = null)
    {
        [$response] = $this->updateGuestQuantityWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity);

        return $response;
    }

    /**
     * Operation updateGuestQuantityWithHttpInfo.
     *
     * @param string                                      $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                      $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateQuantity $update_quantity         The container for the fields used by the &lt;b&gt;updateGuestQuantity&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return array of \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2, HTTP status code, HTTP response headers (array of strings)
     */
    public function updateGuestQuantityWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity = null)
    {
        $request = $this->updateGuestQuantityRequest($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity);

        try {
            $options = $this->createHttpClientOption();

            try {
                $response = $this->client->send($request, $options);
            } catch (RequestException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), $e->getResponse() ? $e->getResponse()->getHeaders() : null, $e->getResponse() ? (string) $e->getResponse()->getBody() : null, $e);
            } catch (ConnectException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            } catch (GuzzleException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            }

            $statusCode = $response->getStatusCode();

            if ($statusCode < 200 || $statusCode > 299) {
                throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, (string) $request->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody());
            }

            switch ($statusCode) {
                case 200:
                    if ('\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2' === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2', []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
            }

            $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';

            if ($returnType === '\SplFileObject') {
                $content = $response->getBody(); // Stream goes to serializer.
            } else {
                $content = (string) $response->getBody();
            }

            return [
                ObjectSerializer::deserialize($content, $returnType, []),
                $response->getStatusCode(),
                $response->getHeaders(),
            ];
        } catch (ApiException $e) {
            switch ($e->getCode()) {
                case 200:
                    $data = ObjectSerializer::deserialize(
                        $e->getResponseBody(),
                        '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2',
                        $e->getResponseHeaders()
                    );
                    $e->setResponseObject($data);
                    break;
            }

            throw $e;
        }
    }

    /**
     * Operation updateGuestQuantityAsync.
     *
     * @param string                                      $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                      $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateQuantity $update_quantity         The container for the fields used by the &lt;b&gt;updateGuestQuantity&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function updateGuestQuantityAsync($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity = null)
    {
        return $this->updateGuestQuantityAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }

    /**
     * Operation updateGuestQuantityAsyncWithHttpInfo.
     *
     * @param string                                      $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                      $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateQuantity $update_quantity         The container for the fields used by the &lt;b&gt;updateGuestQuantity&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function updateGuestQuantityAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity = null)
    {
        $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';
        $request = $this->updateGuestQuantityRequest($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity);

        return $this->client
            ->sendAsync($request, $this->createHttpClientOption())
            ->then(
                function ($response) use ($returnType) {
                    if ($returnType === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, $returnType, []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
                },
                function ($exception) {
                    $response = $exception->getResponse();
                    $statusCode = $response->getStatusCode();

                    throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, $exception->getRequest()->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody(), $exception instanceof \Throwable ? $exception : null);
                }
            );
    }

    /**
     * Create request for operation 'updateGuestQuantity'.
     *
     * @param string                                      $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                      $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateQuantity $update_quantity         The container for the fields used by the &lt;b&gt;updateGuestQuantity&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Psr7\Request
     */
    public function updateGuestQuantityRequest($checkout_session_id, $x_ebay_c_marketplace_id, $update_quantity = null)
    {
        // Verify the required parameter 'checkout_session_id' is set.
        if ($checkout_session_id === null || (\is_array($checkout_session_id) && count($checkout_session_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $checkout_session_id when calling updateGuestQuantity');
        }
        // Verify the required parameter 'x_ebay_c_marketplace_id' is set.
        if ($x_ebay_c_marketplace_id === null || (\is_array($x_ebay_c_marketplace_id) && count($x_ebay_c_marketplace_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $x_ebay_c_marketplace_id when calling updateGuestQuantity');
        }

        $resourcePath = '/guest_checkout_session/{checkoutSessionId}/update_quantity';
        $formParams = [];
        $queryParams = [];
        $headerParams = [];
        $httpBody = '';
        $multipart = false;

        // header params
        if ($x_ebay_c_marketplace_id !== null) {
            $headerParams['X-EBAY-C-MARKETPLACE-ID'] = ObjectSerializer::toHeaderValue($x_ebay_c_marketplace_id);
        }

        // path params
        if ($checkout_session_id !== null) {
            $resourcePath = str_replace(
                '{checkoutSessionId}',
                ObjectSerializer::toPathValue($checkout_session_id),
                $resourcePath
            );
        }

        if ($multipart) {
            $headers = $this->headerSelector->selectHeadersForMultipart(
                ['application/json']
            );
        } else {
            $headers = $this->headerSelector->selectHeaders(
                ['application/json'],
                ['application/json']
            );
        }

        // For model (json/xml)
        if (isset($update_quantity)) {
            if ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode(ObjectSerializer::sanitizeForSerialization($update_quantity));
            } else {
                $httpBody = $update_quantity;
            }
        } elseif (count($formParams) > 0) {
            if ($multipart) {
                $multipartContents = [];

                foreach ($formParams as $formParamName => $formParamValue) {
                    $formParamValueItems = is_array($formParamValue) ? $formParamValue : [$formParamValue];
                    foreach ($formParamValueItems as $formParamValueItem) {
                        $multipartContents[] = [
                            'name' => $formParamName,
                            'contents' => $formParamValueItem,
                        ];
                    }
                }

                // For HTTP post (form)
                $httpBody = new MultipartStream($multipartContents);
            } elseif ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode($formParams);
            } else {
                // For HTTP post (form)
                $httpBody = ObjectSerializer::buildQuery($queryParams);
            }
        }

        // this endpoint requires OAuth (access token)
        if (! empty($this->config->getAccessToken())) {
            $headers['Authorization'] = 'Bearer '.$this->config->getAccessToken();
        }

        $defaultHeaders = [];
        if ($this->config->getUserAgent()) {
            $defaultHeaders['User-Agent'] = $this->config->getUserAgent();
        }

        $headers = array_merge(
            $defaultHeaders,
            $headerParams,
            $headers
        );

        $query = ObjectSerializer::buildQuery($queryParams);

        return new Request(
            'POST',
            $this->config->getHost().$resourcePath.($query ? "?{$query}" : ''),
            $headers,
            $httpBody
        );
    }

    /**
     * Operation updateGuestShippingAddress.
     *
     * @param string                                           $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                           $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\ShippingAddressImpl $shipping_address_impl   The container for the fields used by the &lt;b&gt;updateGuestShippingAddress&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2
     */
    public function updateGuestShippingAddress($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl = null)
    {
        [$response] = $this->updateGuestShippingAddressWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl);

        return $response;
    }

    /**
     * Operation updateGuestShippingAddressWithHttpInfo.
     *
     * @param string                                           $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                           $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\ShippingAddressImpl $shipping_address_impl   The container for the fields used by the &lt;b&gt;updateGuestShippingAddress&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return array of \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2, HTTP status code, HTTP response headers (array of strings)
     */
    public function updateGuestShippingAddressWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl = null)
    {
        $request = $this->updateGuestShippingAddressRequest($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl);

        try {
            $options = $this->createHttpClientOption();

            try {
                $response = $this->client->send($request, $options);
            } catch (RequestException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), $e->getResponse() ? $e->getResponse()->getHeaders() : null, $e->getResponse() ? (string) $e->getResponse()->getBody() : null, $e);
            } catch (ConnectException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            } catch (GuzzleException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            }

            $statusCode = $response->getStatusCode();

            if ($statusCode < 200 || $statusCode > 299) {
                throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, (string) $request->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody());
            }

            switch ($statusCode) {
                case 200:
                    if ('\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2' === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2', []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
            }

            $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';

            if ($returnType === '\SplFileObject') {
                $content = $response->getBody(); // Stream goes to serializer.
            } else {
                $content = (string) $response->getBody();
            }

            return [
                ObjectSerializer::deserialize($content, $returnType, []),
                $response->getStatusCode(),
                $response->getHeaders(),
            ];
        } catch (ApiException $e) {
            switch ($e->getCode()) {
                case 200:
                    $data = ObjectSerializer::deserialize(
                        $e->getResponseBody(),
                        '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2',
                        $e->getResponseHeaders()
                    );
                    $e->setResponseObject($data);
                    break;
            }

            throw $e;
        }
    }

    /**
     * Operation updateGuestShippingAddressAsync.
     *
     * @param string                                           $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                           $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\ShippingAddressImpl $shipping_address_impl   The container for the fields used by the &lt;b&gt;updateGuestShippingAddress&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function updateGuestShippingAddressAsync($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl = null)
    {
        return $this->updateGuestShippingAddressAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }

    /**
     * Operation updateGuestShippingAddressAsyncWithHttpInfo.
     *
     * @param string                                           $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                           $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\ShippingAddressImpl $shipping_address_impl   The container for the fields used by the &lt;b&gt;updateGuestShippingAddress&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function updateGuestShippingAddressAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl = null)
    {
        $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';
        $request = $this->updateGuestShippingAddressRequest($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl);

        return $this->client
            ->sendAsync($request, $this->createHttpClientOption())
            ->then(
                function ($response) use ($returnType) {
                    if ($returnType === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, $returnType, []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
                },
                function ($exception) {
                    $response = $exception->getResponse();
                    $statusCode = $response->getStatusCode();

                    throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, $exception->getRequest()->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody(), $exception instanceof \Throwable ? $exception : null);
                }
            );
    }

    /**
     * Create request for operation 'updateGuestShippingAddress'.
     *
     * @param string                                           $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                           $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\ShippingAddressImpl $shipping_address_impl   The container for the fields used by the &lt;b&gt;updateGuestShippingAddress&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Psr7\Request
     */
    public function updateGuestShippingAddressRequest($checkout_session_id, $x_ebay_c_marketplace_id, $shipping_address_impl = null)
    {
        // Verify the required parameter 'checkout_session_id' is set.
        if ($checkout_session_id === null || (\is_array($checkout_session_id) && count($checkout_session_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $checkout_session_id when calling updateGuestShippingAddress');
        }
        // Verify the required parameter 'x_ebay_c_marketplace_id' is set.
        if ($x_ebay_c_marketplace_id === null || (\is_array($x_ebay_c_marketplace_id) && count($x_ebay_c_marketplace_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $x_ebay_c_marketplace_id when calling updateGuestShippingAddress');
        }

        $resourcePath = '/guest_checkout_session/{checkoutSessionId}/update_shipping_address';
        $formParams = [];
        $queryParams = [];
        $headerParams = [];
        $httpBody = '';
        $multipart = false;

        // header params
        if ($x_ebay_c_marketplace_id !== null) {
            $headerParams['X-EBAY-C-MARKETPLACE-ID'] = ObjectSerializer::toHeaderValue($x_ebay_c_marketplace_id);
        }

        // path params
        if ($checkout_session_id !== null) {
            $resourcePath = str_replace(
                '{checkoutSessionId}',
                ObjectSerializer::toPathValue($checkout_session_id),
                $resourcePath
            );
        }

        if ($multipart) {
            $headers = $this->headerSelector->selectHeadersForMultipart(
                ['application/json']
            );
        } else {
            $headers = $this->headerSelector->selectHeaders(
                ['application/json'],
                ['application/json']
            );
        }

        // For model (json/xml)
        if (isset($shipping_address_impl)) {
            if ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode(ObjectSerializer::sanitizeForSerialization($shipping_address_impl));
            } else {
                $httpBody = $shipping_address_impl;
            }
        } elseif (count($formParams) > 0) {
            if ($multipart) {
                $multipartContents = [];

                foreach ($formParams as $formParamName => $formParamValue) {
                    $formParamValueItems = is_array($formParamValue) ? $formParamValue : [$formParamValue];
                    foreach ($formParamValueItems as $formParamValueItem) {
                        $multipartContents[] = [
                            'name' => $formParamName,
                            'contents' => $formParamValueItem,
                        ];
                    }
                }

                // For HTTP post (form)
                $httpBody = new MultipartStream($multipartContents);
            } elseif ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode($formParams);
            } else {
                // For HTTP post (form)
                $httpBody = ObjectSerializer::buildQuery($queryParams);
            }
        }

        // this endpoint requires OAuth (access token)
        if (! empty($this->config->getAccessToken())) {
            $headers['Authorization'] = 'Bearer '.$this->config->getAccessToken();
        }

        $defaultHeaders = [];
        if ($this->config->getUserAgent()) {
            $defaultHeaders['User-Agent'] = $this->config->getUserAgent();
        }

        $headers = array_merge(
            $defaultHeaders,
            $headerParams,
            $headers
        );

        $query = ObjectSerializer::buildQuery($queryParams);

        return new Request(
            'POST',
            $this->config->getHost().$resourcePath.($query ? "?{$query}" : ''),
            $headers,
            $httpBody
        );
    }

    /**
     * Operation updateGuestShippingOption.
     *
     * @param string                                            $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                            $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateShippingOption $update_shipping_option  The container for the fields used by the &lt;b&gt;updateGuestShippingOption&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2
     */
    public function updateGuestShippingOption($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option = null)
    {
        [$response] = $this->updateGuestShippingOptionWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option);

        return $response;
    }

    /**
     * Operation updateGuestShippingOptionWithHttpInfo.
     *
     * @param string                                            $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                            $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateShippingOption $update_shipping_option  The container for the fields used by the &lt;b&gt;updateGuestShippingOption&lt;/b&gt; method. (optional)
     *
     * @throws \TNT\Ebay\Buy\Order\V2\ApiException on non-2xx response
     * @throws \InvalidArgumentException
     *
     * @return array of \TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2, HTTP status code, HTTP response headers (array of strings)
     */
    public function updateGuestShippingOptionWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option = null)
    {
        $request = $this->updateGuestShippingOptionRequest($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option);

        try {
            $options = $this->createHttpClientOption();

            try {
                $response = $this->client->send($request, $options);
            } catch (RequestException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), $e->getResponse() ? $e->getResponse()->getHeaders() : null, $e->getResponse() ? (string) $e->getResponse()->getBody() : null, $e);
            } catch (ConnectException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            } catch (GuzzleException $e) {
                throw new ApiException("[{$e->getCode()}] {$e->getMessage()}", (int) $e->getCode(), null, null, $e);
            }

            $statusCode = $response->getStatusCode();

            if ($statusCode < 200 || $statusCode > 299) {
                throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, (string) $request->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody());
            }

            switch ($statusCode) {
                case 200:
                    if ('\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2' === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2', []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
            }

            $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';

            if ($returnType === '\SplFileObject') {
                $content = $response->getBody(); // Stream goes to serializer.
            } else {
                $content = (string) $response->getBody();
            }

            return [
                ObjectSerializer::deserialize($content, $returnType, []),
                $response->getStatusCode(),
                $response->getHeaders(),
            ];
        } catch (ApiException $e) {
            switch ($e->getCode()) {
                case 200:
                    $data = ObjectSerializer::deserialize(
                        $e->getResponseBody(),
                        '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2',
                        $e->getResponseHeaders()
                    );
                    $e->setResponseObject($data);
                    break;
            }

            throw $e;
        }
    }

    /**
     * Operation updateGuestShippingOptionAsync.
     *
     * @param string                                            $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                            $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateShippingOption $update_shipping_option  The container for the fields used by the &lt;b&gt;updateGuestShippingOption&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function updateGuestShippingOptionAsync($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option = null)
    {
        return $this->updateGuestShippingOptionAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }

    /**
     * Operation updateGuestShippingOptionAsyncWithHttpInfo.
     *
     * @param string                                            $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                            $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateShippingOption $update_shipping_option  The container for the fields used by the &lt;b&gt;updateGuestShippingOption&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Promise\PromiseInterface
     */
    public function updateGuestShippingOptionAsyncWithHttpInfo($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option = null)
    {
        $returnType = '\TNT\Ebay\Buy\Order\V2\Model\GuestCheckoutSessionResponseV2';
        $request = $this->updateGuestShippingOptionRequest($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option);

        return $this->client
            ->sendAsync($request, $this->createHttpClientOption())
            ->then(
                function ($response) use ($returnType) {
                    if ($returnType === '\SplFileObject') {
                        $content = $response->getBody(); // Stream goes to serializer.
                    } else {
                        $content = (string) $response->getBody();
                    }

                    return [
                        ObjectSerializer::deserialize($content, $returnType, []),
                        $response->getStatusCode(),
                        $response->getHeaders(),
                    ];
                },
                function ($exception) {
                    $response = $exception->getResponse();
                    $statusCode = $response->getStatusCode();

                    throw new ApiException(sprintf('[%d] Error connecting to the API (%s)', $statusCode, $exception->getRequest()->getUri()), $statusCode, $response->getHeaders(), (string) $response->getBody(), $exception instanceof \Throwable ? $exception : null);
                }
            );
    }

    /**
     * Create request for operation 'updateGuestShippingOption'.
     *
     * @param string                                            $checkout_session_id     The eBay-assigned session ID, for a specific eBay marketplace, that is returned by the &lt;b&gt; initiateGuestCheckoutSession&lt;/b&gt; method.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; When using this ID, the X-EBAY-C-MARKETPLACE-ID value and developer App ID must be the same as that used when this guest checkout session was created. See &lt;a href&#x3D;\&quot;/api-docs/buy/order/overview.html#checkout-restriction\&quot;&gt;Checkout session restrictions&lt;/a&gt; in the Buy Integration Guide for details.&lt;/span&gt; (required)
     * @param string                                            $x_ebay_c_marketplace_id A header that identifies the user&#39;s business context and is specified using a marketplace ID value.&lt;br /&gt;&lt;br /&gt;&lt;span class&#x3D;\&quot;tablenote\&quot;&gt;&lt;b&gt;Note:&lt;/b&gt; This header does &lt;i&gt;not&lt;/i&gt; indicate a language preference or consumer location.&lt;/span&gt;&lt;br /&gt;&lt;br /&gt;See &lt;a href&#x3D;\&quot;/api-docs/static/rest-request-components.html#marketpl\&quot; target&#x3D;\&quot;_blank\&quot;&gt;Marketplace ID values&lt;/a&gt; for a list of supported values. (required)
     * @param \TNT\Ebay\Buy\Order\V2\Model\UpdateShippingOption $update_shipping_option  The container for the fields used by the &lt;b&gt;updateGuestShippingOption&lt;/b&gt; method. (optional)
     *
     * @throws \InvalidArgumentException
     *
     * @return \GuzzleHttp\Psr7\Request
     */
    public function updateGuestShippingOptionRequest($checkout_session_id, $x_ebay_c_marketplace_id, $update_shipping_option = null)
    {
        // Verify the required parameter 'checkout_session_id' is set.
        if ($checkout_session_id === null || (\is_array($checkout_session_id) && count($checkout_session_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $checkout_session_id when calling updateGuestShippingOption');
        }
        // Verify the required parameter 'x_ebay_c_marketplace_id' is set.
        if ($x_ebay_c_marketplace_id === null || (\is_array($x_ebay_c_marketplace_id) && count($x_ebay_c_marketplace_id) === 0)) {
            throw new \InvalidArgumentException('Missing the required parameter $x_ebay_c_marketplace_id when calling updateGuestShippingOption');
        }

        $resourcePath = '/guest_checkout_session/{checkoutSessionId}/update_shipping_option';
        $formParams = [];
        $queryParams = [];
        $headerParams = [];
        $httpBody = '';
        $multipart = false;

        // header params
        if ($x_ebay_c_marketplace_id !== null) {
            $headerParams['X-EBAY-C-MARKETPLACE-ID'] = ObjectSerializer::toHeaderValue($x_ebay_c_marketplace_id);
        }

        // path params
        if ($checkout_session_id !== null) {
            $resourcePath = str_replace(
                '{checkoutSessionId}',
                ObjectSerializer::toPathValue($checkout_session_id),
                $resourcePath
            );
        }

        if ($multipart) {
            $headers = $this->headerSelector->selectHeadersForMultipart(
                ['application/json']
            );
        } else {
            $headers = $this->headerSelector->selectHeaders(
                ['application/json'],
                ['application/json']
            );
        }

        // For model (json/xml)
        if (isset($update_shipping_option)) {
            if ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode(ObjectSerializer::sanitizeForSerialization($update_shipping_option));
            } else {
                $httpBody = $update_shipping_option;
            }
        } elseif (count($formParams) > 0) {
            if ($multipart) {
                $multipartContents = [];

                foreach ($formParams as $formParamName => $formParamValue) {
                    $formParamValueItems = is_array($formParamValue) ? $formParamValue : [$formParamValue];
                    foreach ($formParamValueItems as $formParamValueItem) {
                        $multipartContents[] = [
                            'name' => $formParamName,
                            'contents' => $formParamValueItem,
                        ];
                    }
                }

                // For HTTP post (form)
                $httpBody = new MultipartStream($multipartContents);
            } elseif ($headers['Content-Type'] === 'application/json') {
                $httpBody = \GuzzleHttp\json_encode($formParams);
            } else {
                // For HTTP post (form)
                $httpBody = ObjectSerializer::buildQuery($queryParams);
            }
        }

        // this endpoint requires OAuth (access token)
        if (! empty($this->config->getAccessToken())) {
            $headers['Authorization'] = 'Bearer '.$this->config->getAccessToken();
        }

        $defaultHeaders = [];
        if ($this->config->getUserAgent()) {
            $defaultHeaders['User-Agent'] = $this->config->getUserAgent();
        }

        $headers = array_merge(
            $defaultHeaders,
            $headerParams,
            $headers
        );

        $query = ObjectSerializer::buildQuery($queryParams);

        return new Request(
            'POST',
            $this->config->getHost().$resourcePath.($query ? "?{$query}" : ''),
            $headers,
            $httpBody
        );
    }

    /**
     * Create http client option.
     *
     * @throws \RuntimeException on file opening failure
     *
     * @return array of http client options
     */
    protected function createHttpClientOption()
    {
        $options = [];

        if ($this->config->getDebug()) {
            $options[RequestOptions::DEBUG] = fopen($this->config->getDebugFile(), 'ab');

            if (! $options[RequestOptions::DEBUG]) {
                throw new \RuntimeException('Failed to open the debug file: '.$this->config->getDebugFile());
            }
        }

        return $options;
    }
}