增加Payoneer 支付渠道

app/code/Payoneer/OpenPaymentGateway/.gitignore

+# These are some examples of commonly ignored file patterns.
+# You should customize this list as applicable to your project.
+# Learn more about .gitignore:
+#     https://www.atlassian.com/git/tutorials/saving-changes/gitignore
+
+# Node artifact files
+node_modules/
+dist/
+
+# Compiled Java class files
+*.class
+
+# Compiled Python bytecode
+*.py[cod]
+
+# Log files
+*.log
+
+# Package files
+*.jar
+
+# Maven
+target/
+dist/
+
+# JetBrains IDE
+.idea/
+
+# Unit test reports
+TEST*.xml
+
+# Generated by MacOS
+.DS_Store
+
+# Generated by Windows
+Thumbs.db
+
+# Applications
+*.app
+*.exe
+*.war
+
+# Large media files
+*.mp4
+*.tiff
+*.avi
+*.flv
+*.mov
+*.wmv
+

app/code/Payoneer/OpenPaymentGateway/Api/Data/NotificationInterface.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Api\Data;
+
+/**
+ * @api
+ * @since 100.0.2
+ */
+interface NotificationInterface
+{
+    const TABLE = 'payoneer_notification';
+
+    const ID = 'id';
+
+    const TRANSACTION_ID = 'transactionId';
+
+    const LONG_ID = 'longId';
+
+    const ORDER_ID = 'order_id';
+
+    const CONTENT = 'content';
+
+    const CRON_STATUS = 'cron_status';
+
+    const CREATED_AT = 'created_at';
+
+    const UPDATED_AT = 'updated_at';
+
+    /**
+     * Get notification id
+     *
+     * @return int
+     */
+    public function getId();
+
+    /**
+     * Set notification id
+     *
+     * @param int $id
+     * @return $this
+     */
+    public function setId($id);
+    
+    /**
+     * Get transaction id
+     *
+     * @return string
+     */
+    public function getTransactionId();
+
+    /**
+     * Set transaction id
+     *
+     * @param string $txnId
+     * @return $this
+     */
+    public function setTransactionId($txnId);
+
+    /**
+     * Get long id
+     *
+     * @return string
+     */
+    public function getLongId();
+
+    /**
+     * Set long id
+     *
+     * @param string $longId
+     * @return $this
+     */
+    public function setLongId($longId);
+
+    /**
+     * Get order id
+     *
+     * @return string
+     */
+    public function getOrderId();
+
+    /**
+     * Set order id
+     *
+     * @param string $orderId
+     * @return $this
+     */
+    public function setOrderId($orderId);
+
+    /**
+     * Get response content
+     *
+     * @return string
+     */
+    public function getContent();
+
+    /**
+     * Set response content
+     *
+     * @param string $response
+     * @return $this
+     */
+    public function setContent($response);
+
+    /**
+     * Get response processed status
+     *
+     * @return bool
+     */
+    public function getCronStatus();
+
+    /**
+     * Set response processed status
+     *
+     * @param bool $status
+     * @return $this
+     */
+    public function setCronStatus($status);
+}

app/code/Payoneer/OpenPaymentGateway/Api/Data/PayoneerTransactionInterface.php

+<?php
+declare(strict_types=1);
+
+namespace Payoneer\OpenPaymentGateway\Api\Data;
+
+interface PayoneerTransactionInterface
+{
+    /**
+     * Constants for keys of data array. Identical to the name of the getter in snake case.
+     */
+    const TRANSACTION_ID    =   'transaction_id';
+    const CUSTOMER_ID       =   'customer_id';
+    const REGISTRATION_ID   =   'registration_id';
+
+    /**
+     * Get TransactionId.
+     *
+     * @return int
+     */
+    public function getTransactionId();
+
+    /**
+     * Set TransactionId.
+     * @param int $transactionId
+     * @return void
+     */
+    public function setTransactionId($transactionId);
+
+    /**
+     * @return int
+     */
+    public function getCustomerId();
+
+    /**
+     * Set CustomerId.
+     * @param int $customerId.
+     * @return void
+     */
+    public function setCustomerId($customerId);
+
+    /**
+     * Get RegistrationId.
+     *
+     * @return string
+     */
+    public function getRegistrationId();
+
+    /**
+     * Set RegistrationId.
+     * @param string $registrationId.
+     * @return void
+     */
+    public function setRegistrationId($registrationId);
+}

app/code/Payoneer/OpenPaymentGateway/Api/PayoneerNotificationRepositoryInterface.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Api;
+
+use Payoneer\OpenPaymentGateway\Api\Data\NotificationInterface;
+
+/**
+ * @api
+ * @since 100.0.2
+ */
+interface PayoneerNotificationRepositoryInterface
+{
+    /**
+     * Save the notification data
+     *
+     * @param NotificationInterface $notification
+     * @return NotificationInterface
+     * @throws \Magento\Framework\Exception\InputException
+     * @throws \Magento\Framework\Exception\LocalizedException
+     * @throws \Magento\Framework\Exception\CouldNotSaveException
+     */
+    public function save(NotificationInterface $notification);
+}

app/code/Payoneer/OpenPaymentGateway/Api/PayoneerTransactionRepositoryInterface.php

+<?php
+declare(strict_types=1);
+
+namespace Payoneer\OpenPaymentGateway\Api;
+
+use Payoneer\OpenPaymentGateway\Api\Data\PayoneerTransactionInterface;
+
+/**
+ * Grid CRUD interface.
+ * @api
+ */
+interface PayoneerTransactionRepositoryInterface
+{
+
+    /**
+     * @param PayoneerTransactionInterface $payoneerTransaction
+     * @return mixed
+     */
+    public function save(PayoneerTransactionInterface $payoneerTransaction);
+
+    /**
+     * @param int $customerId
+     * @return mixed
+     */
+    public function getByCustomerId($customerId);
+
+    /**
+     * @return mixed
+     */
+    public function create();
+}

app/code/Payoneer/OpenPaymentGateway/Block/Adminhtml/Form/Field/ColorPicker.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Block\Adminhtml\Form\Field;
+
+use Magento\Config\Block\System\Config\Form\Field;
+use Magento\Framework\Data\Form\Element\AbstractElement;
+
+/**
+ * Class ColorPicker
+ * Creates ColorPicker element
+ */
+class ColorPicker extends Field
+{
+    /**
+     * @param AbstractElement $element
+     * @return string
+     */
+    protected function _getElementHtml(AbstractElement $element)
+    {
+        $html = $element->getElementHtml();
+        $value = $element->getData('value');
+
+        $html .= '<script type="text/javascript">
+            require(["jquery","jquery/colorpicker/js/colorpicker"], function ($) {
+                $(document).ready(function () {
+                    var $el = $("#' . $element->getHtmlId() . '");
+                    $el.css("backgroundColor", "' . $value . '");
+
+                    // Attach the color picker
+                    $el.ColorPicker({
+                        color: "' . $value . '",
+                        onChange: function (hsb, hex, rgb) {
+                            $el.css("backgroundColor", "#" + hex).val("#" + hex);
+                        }
+                    });
+                });
+            });
+            </script>';
+        return $html;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Block/Adminhtml/Form/Field/Disable.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Block\Adminhtml\Form\Field;
+
+use Magento\Config\Block\System\Config\Form\Field;
+use Magento\Framework\Data\Form\Element\AbstractElement;
+
+/**
+ * Class Disable
+ * Disables the configuration field
+ */
+class Disable extends Field
+{
+    /**
+     * Disables the configuration field
+     *
+     * @param AbstractElement $element
+     * @return string
+     */
+    protected function _getElementHtml(AbstractElement $element)
+    {
+        $element->setDisabled('disabled');
+        return $element->getElementHtml();
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Block/Adminhtml/Form/Field/ValidateCredentials.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Block\Adminhtml\Form\Field;
+
+use Magento\Config\Block\System\Config\Form\Field;
+use Magento\Framework\Data\Form\Element\AbstractElement;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Store\Model\Store;
+
+/**
+ * Class ValidateCredentials
+ * Creates button for validating the credentials
+ */
+class ValidateCredentials extends Field
+{
+    /**
+     * @inheritDoc
+     */
+    protected function _renderScopeLabel(AbstractElement $element): string
+    {
+        // Return empty label
+        return '';
+    }
+
+    /**
+     * @inheritDoc
+     * @throws LocalizedException
+     */
+    protected function _getElementHtml(AbstractElement $element): string
+    {
+        // Replace field markup with validation button
+        $title = __('Validate credentials');
+        $envId = 'select-groups-payoneer-fields-environment-value';
+        $storeId = 0;
+
+        if ($this->getRequest()->getParam('website')) {
+            $website = $this->_storeManager->getWebsite($this->getRequest()->getParam('website'));
+            if ($website->getId()) {
+                /** @var Store $store */
+                $store = $website->getDefaultStore();/** @phpstan-ignore-line */
+                $storeId = $store->getStoreId();
+            }
+        }
+
+        $endpoint = $this->getUrl('payoneer/configuration/validatecredentials', ['storeId' => $storeId]);
+
+        // @codingStandardsIgnoreStart
+        $html = <<<TEXT
+            <button
+                type="button"
+                title="{$title}"
+                class="button"
+                onclick="payoneerValidator.call(this, '{$endpoint}', '{$envId}')">
+                <span>{$title}</span>
+            </button>
+TEXT;
+        // @codingStandardsIgnoreEnd
+
+        return $html;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Block/Info.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Block;
+
+use Magento\Framework\Phrase;
+use Magento\Payment\Block\ConfigurableInfo;
+
+/**
+ * Class Info
+ *
+ * Info block for Payoneer payment gateway
+ */
+class Info extends ConfigurableInfo
+{
+    /**
+     * Returns label
+     *
+     * @param string $field
+     * @return Phrase
+     */
+    protected function getLabel($field)
+    {
+        return __($field);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Adminhtml/Configuration/ValidateCredentials.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Adminhtml\Configuration;
+
+use Exception;
+use Magento\Backend\App\Action;
+use Magento\Framework\Controller\Result\JsonFactory;
+use Magento\Framework\Controller\ResultFactory;
+use Magento\Framework\Controller\ResultInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\Api\Request;
+
+/**
+ * Class ValidateCredentials
+ * Validate the API Credentials
+ */
+class ValidateCredentials extends Action
+{
+    const ADMIN_RESOURCE = 'Magento_Config::config';
+
+    /**
+     * @var Config
+     */
+    private $config;
+
+    /**
+     * @var Request
+     */
+    private $request;
+
+    /**
+     * Json Factory
+     *
+     * @var JsonFactory
+     */
+    private $jsonResultFactory;
+
+    /**
+     * ValidateCredentials constructor.
+     * @param Action\Context $context
+     * @param Config $config
+     * @param Request $request
+     * @param JsonFactory $jsonResultFactory
+     */
+    public function __construct(
+        Action\Context $context,
+        Config $config,
+        Request $request,
+        JsonFactory $jsonResultFactory
+    ) {
+        parent::__construct($context);
+        $this->config = $config;
+        $this->request = $request;
+        $this->jsonResultFactory = $jsonResultFactory;
+    }
+
+    /**
+     * Validates the field values
+     *
+     * @return ResultInterface
+     */
+    public function execute(): ResultInterface
+    {
+        $gatewayResponse = [];
+        $endPoint = Config::LIST_END_POINT;
+        $data = $this->config->getMockData();
+        $storeCode = $this->getRequest()->getParam('storeCode');
+
+        $credentials['merchantCode'] = $this->getRequest()->getParam('merchantCode');
+        $credentials['apiKey'] = $this->getRequest()->getParam('apiKey');
+        $hostName = $this->getRequest()->getParam('hostName');
+        if ($hostName) {
+            $credentials['hostName'] = $hostName;
+        } else {
+            $credentials['hostName'] = $this->config->getCredentials($this->config::HOST_NAME);
+        }
+        if ($storeCode) {
+            $data['division'] = $storeCode;
+        }
+
+        $response = $this->resultFactory->create(ResultFactory::TYPE_JSON);
+
+        try {
+            $gatewayResponse = $this->request->send(
+                Config::METHOD_POST,
+                $endPoint,
+                $credentials,
+                $data
+            );
+            $response->setHttpResponseCode($gatewayResponse['status']);
+        } catch (Exception $e) {
+            $response->setHttpResponseCode(400);
+        }
+        $result = $this->jsonResultFactory->create();
+        $responseData = isset($gatewayResponse['response'])
+            ? $gatewayResponse['response'] : [];
+        return $result->setData(['data' => $responseData]);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Adminhtml/Gateway/Capture.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Adminhtml\Gateway;
+
+use Magento\Backend\App\Action;
+use Magento\Framework\App\ResponseInterface;
+use Magento\Framework\Controller\Result\Redirect;
+use Magento\Framework\Controller\ResultInterface;
+use Magento\Sales\Model\Order;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\Helper;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\TransactionService as AdminTransactionService;
+
+/**
+ * Class Capture
+ *
+ * Process Payoneer capture request
+ */
+class Capture extends Action
+{
+    /**
+     * @var AdminTransactionService
+     */
+    protected $listCapture;
+
+    /**
+     * @var Helper
+     */
+    protected $helper;
+
+    /**
+     * Capture constructor.
+     *
+     * @param Action\Context $context
+     * @param AdminTransactionService $listCapture
+     * @param Helper $helper
+     */
+    public function __construct(
+        Action\Context $context,
+        AdminTransactionService $listCapture,
+        Helper $helper
+    ) {
+        parent::__construct($context);
+        $this->listCapture = $listCapture;
+        $this->helper = $helper;
+    }
+
+    /**
+     * Process Payoneer capture
+     *
+     * @return ResponseInterface|Redirect|ResultInterface
+     */
+    public function execute()
+    {
+        $resultRedirect = $this->resultRedirectFactory->create();
+        $orderId = (int)$this->getRequest()->getParam('order_id');
+        if ($orderId) {
+            try {
+                /** @var Order $order */
+                $order = $this->helper->getOrder($orderId);
+                /** @var string[] $result */
+                $result = $this->listCapture->process($order, Config::LIST_CAPTURE);
+
+                if ($result) {
+                    $this->helper->processCaptureResponse($result, $order);
+                }
+            } catch (\Exception $e) {
+                $this->helper
+                    ->showErrorMessage(__('Transaction failed') . ' ' . $e->getMessage());
+            }
+        }
+        return $resultRedirect->setPath('sales/order/view', ['order_id' => $orderId]);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Adminhtml/Gateway/Fetch.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Adminhtml\Gateway;
+
+use Magento\Backend\App\Action;
+use Magento\Framework\App\ResponseInterface;
+use Magento\Framework\Controller\Result\Redirect;
+use Magento\Framework\Controller\ResultInterface;
+use Magento\Sales\Model\Order;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\Helper;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\TransactionService as AdminTransactionService;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\TransactionOrderUpdater;
+
+/**
+ * Class Fetch
+ * Process Payoneer fetch request
+ */
+class Fetch extends Action
+{
+    /**
+     * @var AdminTransactionService
+     */
+    protected $transactionService;
+
+    /**
+     * @var Helper
+     */
+    protected $helper;
+
+    /**
+     * @var TransactionOrderUpdater
+     */
+    protected $transactionOrderUpdater;
+
+    /**
+     * Fetch constructor.
+     *
+     * @param Action\Context $context
+     * @param AdminTransactionService $transactionService
+     * @param TransactionOrderUpdater $transactionOrderUpdater
+     * @param Helper $helper
+     * @return void
+     */
+    public function __construct(
+        Action\Context $context,
+        AdminTransactionService $transactionService,
+        TransactionOrderUpdater $transactionOrderUpdater,
+        Helper $helper
+    ) {
+        parent::__construct($context);
+        $this->transactionService = $transactionService;
+        $this->helper=$helper;
+        $this->transactionOrderUpdater=$transactionOrderUpdater;
+    }
+
+    /**
+     * Process Payoneer fetch
+     *
+     * @return ResponseInterface|Redirect|ResultInterface
+     */
+    public function execute()
+    {
+        $resultRedirect = $this->resultRedirectFactory->create();
+        $orderId = (int)$this->getRequest()->getParam('order_id');
+        if ($orderId) {
+            try {
+                /** @var Order $order */
+                $order = $this->helper->getOrder($orderId);
+                /** @var mixed $result */
+                $result = $this->transactionService->process($order, Config::LIST_FETCH);
+                if ($result && $result['status'] == 200) {
+                    $this->transactionOrderUpdater->processFetchUpdateResponse(
+                        $order,
+                        $result
+                    );
+                    $this->helper->showSuccessMessage(
+                        __('Data successfully synced')
+                    );
+                } else {
+                    $this->helper
+                        ->showErrorMessage(
+                            __('Error response with the %1 code received from Payoneer. Check the payoneer.log file for details.', $result['status'])
+                        );
+                }
+            } catch (\Exception $e) {
+                $this->helper
+                    ->showErrorMessage(__('Transaction failed') . ' ' . $e->getMessage());
+            }
+        }
+        return $resultRedirect->setPath('sales/order/view', ['order_id' => $orderId]);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Embedded/Style.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Embedded;
+
+use Magento\Framework\App\Action\HttpGetActionInterface;
+use Magento\Framework\App\ResponseInterface;
+use Magento\Framework\Controller\Result\Raw;
+use Magento\Framework\Controller\Result\RawFactory;
+use Magento\Framework\Controller\ResultInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class Style
+ * Process Style data for embedded integration
+ */
+class Style implements HttpGetActionInterface
+{
+    /**
+     * @var RawFactory
+     */
+    protected $resultRawFactory;
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * Style constructor.
+     * @param RawFactory $resultRawFactory
+     * @param Config $config
+     */
+    public function __construct(
+        RawFactory $resultRawFactory,
+        Config $config
+    ) {
+        $this->resultRawFactory = $resultRawFactory;
+        $this->config = $config;
+    }
+
+    /**
+     * Creates raw css file based on configuration
+     * @return ResponseInterface|Raw|ResultInterface
+     */
+    public function execute()
+    {
+        $styleConfig = $this->config->getStyleConfig();
+        $containerCSS = $this->getContainerStyle($styleConfig);
+        $containerPlaceholderCSS = $this->getContainerPlaceholderStyle();
+        $checkoutCssConfig = $this->config->getValue('widget_appearance/checkout_css');
+
+        $widgetCSS = $containerCSS . $containerPlaceholderCSS;
+        if ($checkoutCssConfig) {
+            $widgetCSS = $widgetCSS . $checkoutCssConfig;
+        }
+        $resultRaw = $this->resultRawFactory->create();
+        $resultRaw->setHeader('Content-type', 'text/css');
+        $resultRaw->setContents($widgetCSS);
+
+        return $resultRaw;
+    }
+
+    /**
+     * Get formatted css for the container
+     * @param array <mixed> $styleConfig
+     * @return string
+     */
+    public function getContainerStyle($styleConfig)
+    {
+        $content = '#networkForm, .op-payment-widget-container {';
+        foreach ($styleConfig as $key => $value) {
+            $content = $content . $key . ':' . $value . ';';
+        }
+        return $content . '}';
+    }
+
+    /**
+     * Get placeholder css
+     * @return string
+     */
+    public function getContainerPlaceholderStyle()
+    {
+        $inputStyle = '';
+        $selectStyle = '';
+        $placeholderValue = $this->config->getValue('widget_appearance/placeholders_color');
+        $phContentClass = '#networkForm ::placeholder, .op-payment-widget-container ::placeholder {';
+        $phContent = $phContentClass . 'opacity: 1;';
+        if ($placeholderValue) {
+            $phColor = 'color:' . $placeholderValue . ';';
+            $phContent = $phContent . $phColor;
+            $inputStyle = '#networkForm ::-ms-input-placeholder, .op-payment-widget-container ::-ms-input-placeholder{'
+                . $phColor . '}';
+            $selectStyle = '#networkForm select {' . $phColor . '}';
+        }
+        $phContent = $phContent . '}';
+        if ($inputStyle) {
+            $phContent = $phContent . $inputStyle . $selectStyle;
+        }
+        return $phContent;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Integration/ProcessPayment.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Integration;
+
+use Exception;
+use Magento\Checkout\Model\Session;
+use Magento\Framework\App\ActionInterface;
+use Magento\Framework\App\RequestInterface as Request;
+use Magento\Framework\Controller\Result\Json;
+use Magento\Framework\Controller\Result\JsonFactory;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Framework\Exception\NoSuchEntityException;
+use Magento\Framework\Message\ManagerInterface;
+use Magento\Payment\Gateway\Command\ResultInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\ListUpdateTransactionService;
+use Payoneer\OpenPaymentGateway\Model\TransactionService;
+
+/**
+ * Class ProcessPayment
+ * Process List request for hosted payment
+ */
+class ProcessPayment implements ActionInterface
+{
+    const LIST_EXPIRED = 'list_expired';
+    const HOSTED = 'hosted';
+
+    /**
+     * @var Session
+     */
+    private $checkoutSession;
+
+    /**
+     * @var TransactionService
+     */
+    private $transactionService;
+
+    /**
+     * @var ListUpdateTransactionService
+     */
+    private $updateTransactionService;
+
+    /**
+     * @var ManagerInterface
+     */
+    protected $messageManager;
+
+    /**
+     * @var Request
+     */
+    protected $request;
+
+    /**
+     * @var JsonFactory
+     */
+    protected $resultJsonFactory;
+
+    /**
+     * ProcessPayment constructor.
+     * @param Session $checkoutSession
+     * @param TransactionService $transactionService
+     * @param ListUpdateTransactionService $updateTransactionService
+     * @param ManagerInterface $messageManager
+     * @param Request $request
+     * @param JsonFactory $resultJsonFactory
+     */
+    public function __construct(
+        Session $checkoutSession,
+        TransactionService $transactionService,
+        ListUpdateTransactionService $updateTransactionService,
+        ManagerInterface $messageManager,
+        Request $request,
+        JsonFactory $resultJsonFactory
+    ) {
+        $this->checkoutSession = $checkoutSession;
+        $this->transactionService = $transactionService;
+        $this->updateTransactionService = $updateTransactionService;
+        $this->messageManager = $messageManager;
+        $this->request = $request;
+        $this->resultJsonFactory = $resultJsonFactory;
+    }
+
+    /**
+     * @return Json | array <mixed>
+     * @throws LocalizedException
+     * @throws NoSuchEntityException
+     * @throws \Exception
+     */
+    public function execute()
+    {
+        $quote = $this->checkoutSession->getQuote();
+        $payment = $quote->getPayment();
+        $additionalInformation = $payment->getAdditionalInformation();
+        /** @phpstan-ignore-next-line */
+        $listId = isset($additionalInformation[Config::LIST_ID]) ?? $additionalInformation[Config::LIST_ID];
+        try {
+            if (!$listId) {
+                $response = $this->transactionService->process($quote);
+            } else {
+                /** @var array <mixed> $response */
+                $response = $this->updateTransactionService->process($quote->getPayment(), Config::LIST_UPDATE);
+
+                //if list session gave an update error, create a new one
+                if ($this->updateError($response)) {
+                    $response = $this->transactionService->process($quote);
+                }
+            }
+            if ($this->isHostedIntegration()) {
+                $jsonData = $this->processHostedResponse($response);
+            } else {
+                $jsonData = $this->processEmbeddedResponse($response);
+            }
+
+            return $this->resultJsonFactory->create()->setData($jsonData);
+        } catch (Exception $e) {
+            return $this->resultJsonFactory->create()->setHttpResponseCode(400)->setData([
+                'error' => $e->getMessage()
+            ]);
+        }
+    }
+
+    /**
+     * @param array <mixed> $result
+     * @return bool
+     */
+    public function isListExpired($result)
+    {
+        if (isset($result['reason']) && str_contains($result['reason'], self::LIST_EXPIRED)) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * @param array <mixed> $result
+     * @return bool
+     */
+    public function updateError($result)
+    {
+        if (isset($result['status']) && ($result['status'] == 422 || $result['status'] == 409)) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * Process response of hosted integration
+     * @param ResultInterface|null|bool|array <mixed> $result
+     * @return array <mixed>
+     * @throws LocalizedException
+     * @throws NoSuchEntityException
+     */
+    public function processHostedResponse($result)
+    {
+        if ($result && isset($result['response']['redirect'])) {
+            $redirectURL =  $result['response']['redirect']['url'];
+        } else {
+            $quote = $this->checkoutSession->getQuote();
+            $payment = $quote->getPayment();
+            $additionalInformation = $payment->getAdditionalInformation();
+            if (isset($additionalInformation[Config::REDIRECT_URL])) {
+                $redirectURL = $additionalInformation[Config::REDIRECT_URL];
+            } else {
+                $this->messageManager->addErrorMessage(__('We couldn\'t process the payment'));
+            }
+        }
+        return (isset($redirectURL)? ['redirectURL' => $redirectURL]: []);
+    }
+
+    /**
+     * Process response of embedded integration
+     * @param ResultInterface|null|bool|array <mixed> $result
+     * @return array <mixed>
+     */
+    public function processEmbeddedResponse($result)
+    {
+        $jsonData = [];
+        if ($result && isset($result['response']['links'])) {
+            $jsonData = [
+                'links' => $result['response']['links']
+            ];
+        } else {
+            $this->messageManager->addErrorMessage(__('We couldn\'t process the payment'));
+        }
+        return $jsonData;
+    }
+
+    /**
+     * @return bool
+     */
+    public function isHostedIntegration()
+    {
+        return $this->request->getParam(Config::INTEGRATION) == Config::INTEGRATION_HOSTED;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Redirect/Cancel.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Redirect;
+
+use Magento\Framework\App\Action\Context;
+use Magento\Framework\App\Action\HttpGetActionInterface;
+use Magento\Framework\App\ResponseInterface;
+use Magento\Framework\Controller\ResultInterface;
+use Magento\Framework\Exception\CouldNotSaveException;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Framework\Exception\NoSuchEntityException;
+use Magento\Framework\View\Result\Page;
+use Magento\Quote\Api\CartRepositoryInterface;
+use Magento\Quote\Model\Quote;
+use Magento\Sales\Api\TransactionRepositoryInterface;
+use Magento\Sales\Model\Order\Payment\Transaction;
+use Magento\Sales\Model\ResourceModel\Order\Payment\Transaction\CollectionFactory as OrderTransactionCollectionFactory;
+use Payoneer\OpenPaymentGateway\Model\Helper;
+use Payoneer\OpenPaymentGateway\Logger\NotificationLogger;
+use Magento\Checkout\Model\Session as CheckoutSession;
+
+/**
+ * Class Cancel
+ * Process CANCEL request
+ */
+class Cancel implements HttpGetActionInterface
+{
+    /**
+     * @var Context
+     */
+    private $context;
+
+    /**
+     * @var CartRepositoryInterface
+     */
+    private $cartRepository;
+
+    /**
+     * @var Helper
+     */
+    private $helper;
+
+    /**
+     * @var TransactionRepositoryInterface
+     */
+    private $transactionRepository;
+
+    /**
+     * @var OrderTransactionCollectionFactory
+     */
+    protected $orderTransactionCollectionFactory;
+
+    /**
+     * @var NotificationLogger
+     */
+    protected $notificationLogger;
+
+    /**
+     * @var CheckoutSession
+     */
+    protected $checkoutSession;
+
+    /**
+     * Helper constructor.
+     * @param Context $context
+     * @param CartRepositoryInterface $cartRepository
+     * @param Helper $helper
+     * @param TransactionRepositoryInterface $transactionRepository
+     * @param OrderTransactionCollectionFactory $orderTransactionCollectionFactory
+     * @param NotificationLogger $notificationLogger
+     * @param CheckoutSession $checkoutSession
+     */
+    public function __construct(
+        Context $context,
+        CartRepositoryInterface $cartRepository,
+        Helper $helper,
+        TransactionRepositoryInterface $transactionRepository,
+        OrderTransactionCollectionFactory $orderTransactionCollectionFactory,
+        NotificationLogger $notificationLogger,
+        CheckoutSession $checkoutSession
+    ) {
+        $this->context = $context;
+        $this->cartRepository = $cartRepository;
+        $this->helper = $helper;
+        $this->transactionRepository = $transactionRepository;
+        $this->orderTransactionCollectionFactory = $orderTransactionCollectionFactory;
+        $this->notificationLogger = $notificationLogger;
+        $this->checkoutSession = $checkoutSession;
+    }
+
+    /**
+     * @return ResponseInterface|ResultInterface|Page
+     */
+    public function execute()
+    {
+        $reqParams = $this->context->getRequest()->getParams();
+
+        try {
+            // Session to skip order confirmation email sending
+            $this->checkoutSession->setIsPayoneerCancelledOrder(true);
+            $this->checkoutSession->setPayoneerSkipInvoiceCreation(true);
+            $this->helper->setPayoneerInvalidTxnSession();
+            // Place order with invalid transaction details
+            $this->saveCartAndPlaceOrder($reqParams);
+            // Restore quote
+            $this->checkoutSession->restoreQuote();
+            // Update the invalid order transaction type to void
+            $this->updateTransactionType();
+            //Add comment to the order
+            $this->helper->addCommentToOrder();
+        } catch (\Exception $e) {
+            $this->notificationLogger->addError(
+                'CancelError - ' . $e->getMessage()
+            );
+        }
+        return $this->helper->redirectToCart(
+            __('We couldn\'t process the payment')
+        );
+    }
+
+    /**
+     * @param array <mixed> $reqParams
+     * @throws CouldNotSaveException
+     * @throws LocalizedException
+     * @throws NoSuchEntityException
+     * @return void
+     */
+    public function saveCartAndPlaceOrder($reqParams)
+    {
+        $cartId = $reqParams['cart_id'];
+        if ($cartId) {
+            /** @var Quote $quote */
+            $quote = $this->cartRepository->getActive($reqParams['cart_id']);
+            $payment = $quote->getPayment();
+            foreach ($reqParams as $key => $value) {
+                $payment->setAdditionalInformation($key, $value);
+            }
+            $quote->setPayment($payment);
+
+            if (!$quote->getCustomerId()) {
+                $quote = $this->helper->setGuestCustomerEmail($quote);
+            }
+            $this->cartRepository->save($quote);
+
+            $this->helper->placeOrder($reqParams['cart_id']);
+        }
+    }
+
+    /**
+     * Updates transaction type to 'void'
+     *
+     * @return void
+     */
+    public function updateTransactionType()
+    {
+        $orderId = $this->helper->getLastOrderId();
+        $collection = $this->orderTransactionCollectionFactory->create();
+        $collection->addOrderIdFilter($orderId);
+        if ($collection->getSize()) {
+            /** @var  Transaction $transaction */
+            $transaction = $collection->getFirstItem();
+            $transaction->setTxnType('void');
+            $transaction->setIsClosed(1);
+            $this->transactionRepository->save($transaction);
+        }
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Redirect/Notification.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Redirect;
+
+use Exception;
+use Magento\Framework\App\CsrfAwareActionInterface;
+use Magento\Framework\App\Request\Http;
+use Magento\Framework\App\Request\InvalidRequestException;
+use Magento\Framework\App\RequestInterface;
+use Magento\Framework\App\ResponseInterface;
+use Magento\Framework\Controller\ResultInterface;
+use Payoneer\OpenPaymentGateway\Api\Data\NotificationInterfaceFactory;
+use Payoneer\OpenPaymentGateway\Api\PayoneerNotificationRepositoryInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\PayoneerNotification;
+use Payoneer\OpenPaymentGateway\Model\PayoneerNotificationFactory;
+use Magento\Sales\Model\ResourceModel\Order\CollectionFactory as OrderCollectionFactory;
+use Payoneer\OpenPaymentGateway\Logger\NotificationLogger;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\Helper;
+use Payoneer\OpenPaymentGateway\Model\TransactionOrderUpdater;
+
+/**
+ * Class Notification
+ *
+ * Process Notification request
+ */
+class Notification implements CsrfAwareActionInterface
+{
+    /**
+     * @var PayoneerNotificationFactory
+     */
+    protected $payoneerNotification;
+
+    /**
+     * @var Http
+     */
+    protected $request;
+
+    /**
+     * @var PayoneerNotificationRepositoryInterface
+     */
+    protected $notificationRepository;
+
+    /**
+     * @var NotificationInterfaceFactory
+     */
+    protected $notificationFactory;
+
+    /**
+     * @var OrderCollectionFactory
+     */
+    protected $orderCollectionFactory;
+
+    /**
+     * @var NotificationLogger
+     */
+    protected $notificationLogger;
+
+    /**
+     * @var TransactionOrderUpdater
+     */
+    protected $transactionOrderUpdater;
+
+    /**
+     * Notification constructor.
+     *
+     * @param PayoneerNotificationFactory $payoneerNotification
+     * @param PayoneerNotificationRepositoryInterface $notificationRepository
+     * @param NotificationInterfaceFactory $notificationFactory
+     * @param OrderCollectionFactory $orderCollectionFactory
+     * @param NotificationLogger $notificationLogger
+     * @param Http $request
+     * @param TransactionOrderUpdater $transactionOrderUpdater
+     */
+    public function __construct(
+        PayoneerNotificationFactory $payoneerNotification,
+        PayoneerNotificationRepositoryInterface $notificationRepository,
+        NotificationInterfaceFactory $notificationFactory,
+        OrderCollectionFactory $orderCollectionFactory,
+        NotificationLogger $notificationLogger,
+        Http $request,
+        TransactionOrderUpdater $transactionOrderUpdater
+    ) {
+        $this->payoneerNotification = $payoneerNotification;
+        $this->notificationRepository = $notificationRepository;
+        $this->notificationFactory = $notificationFactory;
+        $this->request = $request;
+        $this->orderCollectionFactory = $orderCollectionFactory;
+        $this->notificationLogger = $notificationLogger;
+        $this->transactionOrderUpdater = $transactionOrderUpdater;
+    }
+
+    /**
+     * Listen notification from payoneer side and save to db.
+     *
+     * @return ResponseInterface|ResultInterface|void|null
+     * @throws Exception
+     */
+    public function execute()
+    {
+        try {
+            $urlParams = $this->request->getParams();
+            $post = $this->request->getContent();
+            $postArray = \Safe\json_decode($post, true);
+            if ($postArray['entity'] == Config::ENTITY_PAYMENT) {
+                /** @var  PayoneerNotification $notification */
+                $notification = $this->notificationFactory->create();
+                $notification->addData([
+                    'transactionId' => $postArray['transactionId'],
+                    'longId' => $postArray['longId'],
+                    'content' => $post,
+                    'order_id' => $urlParams['order_id'],
+                    'cron_status' => 0
+                ]);
+                $this->notificationRepository->save($notification);
+                if (isset($postArray['statusCode']) &&
+                    isset($postArray['interactionReason']) &&
+                    $postArray['interactionReason'] != Helper::SYSTEM_FAILURE
+                ) {
+                    $this->transactionOrderUpdater->processNotificationResponse(
+                        $notification->getOrderId(),
+                        $postArray
+                    );
+                    $notification->setCronStatus(true);
+                    $this->notificationRepository->save($notification);
+                }
+            }
+        } catch (Exception $e) {
+            $this->notificationLogger->addError(
+                __(
+                    'ErrorMessage = %1, OrderId = %2, NotificationResponse = %3.',
+                    $e->getMessage(),
+                    $urlParams['order_id'],
+                    $post
+                )
+            );
+        }
+        exit; // @codingStandardsIgnoreLine
+    }
+
+    /**
+     * Get the token from the order payment additional info.
+     *
+     * @param string $orderId
+     * @return string|null
+     */
+    private function getTokenFromOrder($orderId)
+    {
+        $collection = $this->orderCollectionFactory->create();
+        $collection->addFieldToFilter('increment_id', ['eq' => $orderId]);
+        if ($collection->getSize()) {
+            $order = $collection->getFirstItem();
+            $payment = $order->getPayment();
+            return $payment->getAdditionalInformation(Config::TOKEN_NOTIFICATION);
+        }
+        return null;
+    }
+
+    /**
+     * @param RequestInterface $request
+     * @return InvalidRequestException|null
+     */
+    public function createCsrfValidationException(RequestInterface $request): ?InvalidRequestException
+    {
+        return null;
+    }
+
+    /**
+     * @param RequestInterface $request
+     * @return bool|null
+     */
+    public function validateForCsrf(RequestInterface $request): ?bool
+    {
+        $orderId = $request->getParam('order_id');
+        $notificationToken = $request->getParam('token');
+        $orderToken = $this->getTokenFromOrder($orderId);
+        if ($notificationToken == '' || $notificationToken == null || $notificationToken != $orderToken) {
+            $this->notificationLogger->addError(
+                __(
+                    'Invalid token for order #%1, order token = %2, received token = %3',
+                    $orderId,
+                    $orderToken,
+                    $notificationToken
+                )
+            );
+            return false;
+        }
+        return true;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Controller/Redirect/Success.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Controller\Redirect;
+
+use Magento\Checkout\Model\Session;
+use Magento\Framework\App\Action\Context;
+use Magento\Framework\App\Action\HttpGetActionInterface;
+use Magento\Framework\App\ResponseInterface;
+use Magento\Framework\Controller\Result\Redirect;
+use Magento\Framework\Controller\ResultInterface;
+use Magento\Framework\View\Result\Page;
+use Magento\Framework\View\Result\PageFactory;
+use Magento\Quote\Api\CartManagementInterface;
+use Magento\Quote\Api\CartRepositoryInterface;
+use Magento\Quote\Model\Quote;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\Source\Fields as AdminFields;
+use Payoneer\OpenPaymentGateway\Model\Helper;
+
+/**
+ * Class Success
+ * Process SUCCESS request
+ */
+class Success implements HttpGetActionInterface
+{
+    const INTERACTION_CODE_PROCEED = 'PROCEED';
+
+    /**
+     * @var Context
+     */
+    private $context;
+
+    /**
+     * @var CartRepositoryInterface
+     */
+    private $cartRepository;
+
+    /**
+     * @var PageFactory
+     */
+    private $resultPageFactory;
+
+    /**
+     * @var Helper
+     */
+    protected $helper;
+
+    /**
+     * @var Session
+     */
+    private $checkoutSession;
+
+    /**
+     * @var Config
+     */
+    private $config;
+
+    /**
+     * Success constructor.
+     * @param Context $context
+     * @param CartRepositoryInterface $cartRepository
+     * @param PageFactory $resultPageFactory
+     * @param Helper $helper
+     * @param Session $checkoutSession
+     * @param Config $config
+     */
+    public function __construct(
+        Context $context,
+        CartRepositoryInterface $cartRepository,
+        PageFactory $resultPageFactory,
+        Helper $helper,
+        Session $checkoutSession,
+        Config $config
+    ) {
+        $this->context = $context;
+        $this->cartRepository = $cartRepository;
+        $this->resultPageFactory = $resultPageFactory;
+        $this->helper = $helper;
+        $this->checkoutSession = $checkoutSession;
+        $this->config = $config;
+    }
+
+    /**
+     * Dispatch request
+     * @return ResponseInterface|Redirect|ResultInterface|Page
+     */
+    public function execute()
+    {
+        $reqParams = $this->context->getRequest()->getParams();
+        try {
+            if (isset($reqParams['listUrl']) &&
+                isset($reqParams['interactionCode']) &&
+                $reqParams['interactionCode'] == self::INTERACTION_CODE_PROCEED
+            ) {
+                $cartId = $reqParams['cart_id'];
+                /** @var Quote $quote */
+                $quote = $this->cartRepository->getActive($cartId);
+                $quoteData = $quote->getData();
+                $payment = $quote->getPayment();
+                if (!isset($reqParams['token'])
+                    || $reqParams['token'] == ''
+                    || $reqParams['token'] == null
+                    || $payment->getAdditionalInformation('token') != $reqParams['token']
+                ) {
+                    return $this->redirectToCart();
+                } else {
+                    foreach ($reqParams as $key => $value) {
+                        $payment->setAdditionalInformation($key, $value);
+                    }
+                    if ($this->config->getValue('payment_action') == AdminFields::CAPTURE) {
+                        $payment->setAdditionalInformation('payoneerCapture', 'Success');
+                    }
+                    $quote->setPayment($payment);
+                }
+
+                if ($quote->getCustomerId() && isset($reqParams['customerRegistrationId'])) {
+                    $this->helper->saveRegistrationId($reqParams['customerRegistrationId'], $quote->getCustomerId());
+                }
+
+                if (!$quote->getCustomerId()) {
+                    $quote = $this->helper->setGuestCustomerEmail($quote);
+                } else {
+                    $this->helper->unsetPayoneerCustomerEmailSession();
+                }
+                $this->cartRepository->save($quote);
+
+                if ($quoteData['grand_total'] != $reqParams['amount']) {
+                    $this->checkoutSession->setUpdateOrderStatus(true);
+                }
+                //Place order in magento
+                $this->helper->placeOrder($cartId);
+                //Unset custom Payoneer sessions
+                $this->helper->unsetPayoneerCountryIdSession();
+                return $this->resultPageFactory->create();
+            } else {
+                return $this->redirectToCart();
+            }
+        } catch (\Exception $e) {
+            return $this->redirectToCart($e->getMessage());
+        }
+    }
+
+    /**
+     * @param string|null $message
+     * @return Redirect
+     */
+    public function redirectToCart($message = null)
+    {
+        if (!$message) {
+            $message = 'We couldn\'t process the payment. Invalid response from Payoneer.';
+        }
+        return $this->helper->redirectToCart(__($message));
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Cron/OrderUpdate.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Cron;
+
+use Magento\Framework\Stdlib\DateTime\TimezoneInterface;
+use Payoneer\OpenPaymentGateway\Model\ResourceModel\PayoneerNotification\CollectionFactory;
+use Payoneer\OpenPaymentGateway\Model\TransactionOrderUpdater;
+use Payoneer\OpenPaymentGateway\Model\ResourceModel\PayoneerNotification\Collection;
+use Payoneer\OpenPaymentGateway\Logger\NotificationLogger;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\NotificationEmailSender;
+use Payoneer\OpenPaymentGateway\Api\PayoneerNotificationRepositoryInterface;
+
+/**
+ * Update order on running cron with notification data
+ */
+class OrderUpdate
+{
+    /**
+     * @var CollectionFactory
+     */
+    private $notificationCollectionFactory;
+
+    /**
+     * @var TransactionOrderUpdater
+     */
+    protected $transactionOrderUpdater;
+
+    /**
+     * @var NotificationLogger
+     */
+    protected $notificationLogger;
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * @var TimezoneInterface
+     */
+    protected $timezone;
+
+    /**
+     * @var NotificationEmailSender
+     */
+    protected $emailSender;
+
+    /**
+     * @var PayoneerNotificationRepositoryInterface
+     */
+    protected $notificationRepository;
+
+    /**
+     * OrderUpdate construct function
+     *
+     * @param CollectionFactory $notificationCollectionFactory
+     * @param TransactionOrderUpdater $transactionOrderUpdater
+     * @param NotificationLogger $notificationLogger
+     * @param Config $config
+     * @param TimezoneInterface $timezone
+     * @param NotificationEmailSender $emailSender
+     * @param PayoneerNotificationRepositoryInterface $notificationRepository
+     * @return void
+     */
+    public function __construct(
+        CollectionFactory $notificationCollectionFactory,
+        TransactionOrderUpdater $transactionOrderUpdater,
+        NotificationLogger $notificationLogger,
+        Config $config,
+        TimezoneInterface $timezone,
+        NotificationEmailSender $emailSender,
+        PayoneerNotificationRepositoryInterface $notificationRepository
+    ) {
+        $this->notificationCollectionFactory = $notificationCollectionFactory;
+        $this->transactionOrderUpdater = $transactionOrderUpdater;
+        $this->notificationLogger = $notificationLogger;
+        $this->config = $config;
+        $this->timezone = $timezone;
+        $this->emailSender = $emailSender;
+        $this->notificationRepository = $notificationRepository;
+    }
+
+    /**
+     * Get the non-processed notification and process it.
+     *
+     * @return bool|void
+     */
+    public function execute()
+    {
+        try {
+            $notificationCollection = $this->getNotificationsToCleanUp();
+            if ($notificationCollection != null) {
+                /** @phpstan-ignore-next-line */
+                $notificationCollection->walk('delete');
+            }
+        } catch (\Exception $e) {
+            $this->notificationLogger->addError(
+                __('NotificationCleanupError: %1', $e->getMessage())
+            );
+        }
+        try {
+            $notificationCollection = $this->getNotificationsToSendEmail();
+            if ($notificationCollection != null) {
+                foreach ($notificationCollection as $notification) {
+                    $response = \Safe\json_decode($notification->getContent(), true);
+                    $this->emailSender->send($response);
+                    $notification->setSendEmail(true);
+                    $this->notificationRepository->save($notification);
+                }
+            }
+        } catch (\Exception $e) {
+            $this->notificationLogger->addError(
+                __('NotificationEmailSendError: %1', $e->getMessage())
+            );
+        }
+    }
+
+    /**
+     * Get all the notifications to cleanup
+     *
+     * @return Collection|null
+     */
+    private function getNotificationsToCleanUp()
+    {
+        $cleanupDays = $this->config->getValue(Config::NOTIFICATION_CLEANUP_DAYS_PATH);
+        if (empty($cleanupDays)) {
+            return null;
+        }
+        $collection = $this->notificationCollectionFactory->create();
+        $collection->addFieldToFilter('cron_status', ['eq' => 1]);
+        $collection->addFieldToFilter(
+            'created_at',
+            ['lteq' => $this->getUtcDateXDaysBefore($cleanupDays)]
+        );
+
+        return $collection;
+    }
+
+    /**
+     * Get all the notifications to which the email should be send
+     *
+     * @return Collection|null
+     */
+    private function getNotificationsToSendEmail()
+    {
+        $emailSendDays = $this->config->getValue(Config::EMAIL_NOTIFICATION_DAYS_PATH);
+        if (empty($emailSendDays)) {
+            return null;
+        }
+        $collection = $this->notificationCollectionFactory->create();
+        $collection->addFieldToFilter('cron_status', ['eq' => 0]);
+        $collection->addFieldToFilter('send_email', ['eq' => 0]);
+        $collection->addFieldToFilter(
+            'created_at',
+            ['lteq' => $this->getUtcDateXDaysBefore($emailSendDays)]
+        );
+
+        return $collection;
+    }
+
+    /**
+     * Get the date in UTC timezone
+     *
+     * @param int $noOfDays
+     * @return string
+     */
+    private function getUtcDateXDaysBefore($noOfDays)
+    {
+        return $this->timezone->date()->setTimezone(new \DateTimeZone('UTC'))
+            ->modify('-' . $noOfDays . ' day')
+            ->format('Y-m-d 23:59:59');
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Command/GatewayCommand.php

+<?php
+namespace Payoneer\OpenPaymentGateway\Gateway\Command;
+
+use Magento\Checkout\Model\Session;
+use Magento\Payment\Gateway\Command\CommandException;
+use Magento\Payment\Gateway\Command\ResultInterface as CommandResultInterface;
+use Magento\Payment\Gateway\CommandInterface;
+use Magento\Payment\Gateway\ErrorMapper\ErrorMessageMapperInterface;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Http\ClientException;
+use Magento\Payment\Gateway\Http\ClientInterface;
+use Magento\Payment\Gateway\Http\ConverterException;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Magento\Payment\Gateway\Response\HandlerInterface;
+use Magento\Payment\Gateway\Validator\ResultInterface;
+use Magento\Payment\Gateway\Validator\ValidatorInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Http\TransferFactoryInterface;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Class GatewayCommand
+ *
+ * GatewayCommand for Payoneer payment
+ */
+class GatewayCommand implements CommandInterface
+{
+    /**
+     * @var BuilderInterface
+     */
+    protected $requestBuilder;
+
+    /**
+     * @var TransferFactoryInterface
+     */
+    protected $transferFactory;
+
+    /**
+     * @var ClientInterface
+     */
+    protected $client;
+
+    /**
+     * @var LoggerInterface
+     */
+    protected $logger;
+
+    /**
+     * @var HandlerInterface|null
+     */
+    protected $handler;
+
+    /**
+     * @var ValidatorInterface|null
+     */
+    protected $validator;
+
+    /**
+     * @var ErrorMessageMapperInterface|null
+     */
+    private $errorMessageMapper;
+
+    /**
+     * @var Session
+     */
+    private $session;
+
+    /**
+     * Gateway command constructor
+     *
+     * @param BuilderInterface $requestBuilder
+     * @param TransferFactoryInterface $transferFactory
+     * @param ClientInterface $client
+     * @param LoggerInterface $logger
+     * @param Session $checkoutSession
+     * @param HandlerInterface $handler
+     * @param ValidatorInterface $validator
+     * @param ErrorMessageMapperInterface|null $errorMessageMapper
+     *
+     */
+    public function __construct(
+        BuilderInterface $requestBuilder,
+        TransferFactoryInterface $transferFactory,
+        ClientInterface $client,
+        LoggerInterface $logger,
+        Session $checkoutSession,
+        HandlerInterface $handler = null,
+        ValidatorInterface $validator = null,
+        ErrorMessageMapperInterface $errorMessageMapper = null
+    ) {
+        $this->requestBuilder = $requestBuilder;
+        $this->transferFactory = $transferFactory;
+        $this->client = $client;
+        $this->logger = $logger;
+        $this->session = $checkoutSession;
+        $this->handler = $handler;
+        $this->validator = $validator;
+        $this->errorMessageMapper = $errorMessageMapper;
+    }
+
+    /**
+     * Executes command basing on business object
+     *
+     * @param array <mixed> $commandSubject
+     * @return CommandResultInterface | array <mixed>
+     * @throws CommandException
+     * @throws ClientException
+     * @throws ConverterException
+     */
+    public function execute(array $commandSubject)
+    {
+        $response = [];
+        $payment = SubjectReader::readPayment($commandSubject);
+        $transferO = $this->transferFactory->create(
+            $this->requestBuilder->build($commandSubject),
+            $payment
+        );
+        //process payoneer request only if it is not via fetch or notification
+        if ($this->session->getFetchNotificationResponse()) {
+            $response = $this->session->getFetchNotificationResponse();
+        } else {
+            $response = $this->client->placeRequest($transferO);
+
+            if ($this->validator !== null) {
+                $result = $this->validator->validate(
+                    array_merge($commandSubject, ['response' => $response])
+                );
+                if (!$result->isValid()) {
+                    $this->processErrors($result);
+                }
+            }
+
+        }
+
+        if ($this->handler) {
+            $this->handler->handle(
+                $commandSubject,
+                $response
+            );
+        }
+
+        if ($this->session->getFetchNotificationResponse()) {
+            $this->session->unsFetchNotificationResponse();
+        }
+
+        return $response;
+    }
+
+    /**
+     * Tries to map error messages from validation result and logs processed message.
+     * Throws an exception with mapped message or default error.
+     *
+     * @param ResultInterface $result
+     * @return void
+     * @throws CommandException
+     */
+    private function processErrors(ResultInterface $result)
+    {
+        $messages = [];
+        $errorCodeOrMessage = null;
+        $errorsSource = array_merge($result->getErrorCodes(), $result->getFailsDescription());
+
+        foreach ($errorsSource as $errorCodeOrMessage) {
+            $errorCodeOrMessage = (string) $errorCodeOrMessage;
+
+            // error messages mapper can be not configured if payment method doesn't have custom error messages.
+            if ($this->errorMessageMapper !== null) {
+                $mapped = (string) $this->errorMessageMapper->getMessage($errorCodeOrMessage);
+                if (!empty($mapped)) {
+                    $messages[] = $mapped;
+                    $errorCodeOrMessage = $mapped;
+                }
+            }
+
+            $this->logger->critical('Payment Error: ' . $errorCodeOrMessage);
+        }
+
+        $exceptionMessage = $errorCodeOrMessage ?: 'Transaction declined. Try again later.';
+
+        throw new CommandException(
+            !empty($messages)
+                ? __(implode(PHP_EOL, $messages))
+                : __($exceptionMessage)
+        );
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/Authorization/CancellationTransferFactory.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http\Authorization;
+
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Magento\Payment\Gateway\Data\PaymentDataObjectInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Http\TransferFactory;
+
+/**
+ * Class CancellationTransferFactory
+ *
+ * Builds authorization cancellation transfer object
+ */
+class CancellationTransferFactory extends TransferFactory
+{
+    /**
+     * @inheritDoc
+     */
+    protected function getApiUri(PaymentDataObjectInterface $payment)
+    {
+        $longId = $payment->getPayment()->getAdditionalInformation('longId');
+
+        return sprintf(
+            Config::AUTHORIZATION_CANCEL_END_POINT,
+            $longId
+        );
+    }
+
+    /**
+     * @inheritDoc
+     */
+    protected function getMethod()
+    {
+        return Config::METHOD_DELETE;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/Client/Client.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http\Client;
+
+use Magento\Framework\DataObject;
+use Magento\Payment\Gateway\Http\ClientInterface;
+use Magento\Payment\Gateway\Http\TransferInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\Api\Request;
+use Payoneer\OpenPaymentGateway\Model\Method\Logger;
+
+/**
+ * Class Client
+ * Payoneer client for transactions
+ */
+class Client implements ClientInterface
+{
+    const AUTHORIZE             =   'authorize';
+    const LIST                  =   'list';
+    const CAPTURE               =   'authorize_capture';
+    const AUTHORIZATION_CANCEL  =   'authorize_cancel';
+    const REFUND                =   'refund';
+    const VOID                  =   'void';
+    const LIST_FETCH            =   'list_fetch';
+    const LIST_CAPTURE          =   'list_capture';
+    const LIST_UPDATE           =   'list_update';
+    const LIST_DELETE           =   'list_delete';
+    const PREAUTH_CANCEL        =   'preauth_cancel';
+
+    /**
+     * @var Logger
+     */
+    protected $logger;
+
+    /**
+     * @var Request
+     */
+    protected $request;
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * @var string
+     */
+    protected $operation;
+
+    /**
+     * Mandatory request fields
+     * @var string[]
+     */
+    protected $mandatoryFields = [
+        'transactionId',
+        'country',
+        'customer',
+        'payment',
+        'callback'
+    ];
+
+    /**
+     * Mandatory request fields for 'payment' object
+     * @var string[]
+     */
+    protected $mandatoryFieldsPayment = [
+        'amount',
+        'currency',
+        'reference',
+        'invoiceId'
+    ];
+
+    /**
+     * Mandatory request fields for 'customer' object
+     * @var string[]
+     */
+    protected $mandatoryFieldsCustomer = [
+        'number'
+    ];
+
+    /**
+     * @var array <mixed> | string
+     */
+    protected $requestData;
+
+    /**
+     * Client construct
+     *
+     * @param Logger $logger
+     * @param Request $request
+     * @param Config $config
+     * @param string $operation
+     * @return void
+     */
+    public function __construct(
+        Logger $logger,
+        Request $request,
+        Config $config,
+        $operation
+    ) {
+        $this->logger = $logger;
+        $this->request = $request;
+        $this->config = $config;
+        $this->operation = $operation;
+    }
+
+    /**
+     * @param TransferInterface $transferObject
+     * @return array|DataObject
+     * @return array <mixed>
+     */
+    public function placeRequest(TransferInterface $transferObject)
+    {
+        $response = [];
+        $responseObj = null;
+        $this->requestData = $transferObject->getBody();
+        $this->logData(['operation' => $this->operation]);
+        switch ($this->operation) {
+            case self::LIST:
+            case self::LIST_UPDATE:
+                $isRequestValid = $this->validateRequest();
+                if ($isRequestValid) {
+                    $responseObj = $this->processRequest($transferObject);
+                } else {
+                    $this->logData(['request' => $this->requestData]);
+                }
+                break;
+            case self::AUTHORIZE:
+            case self::CAPTURE:
+                $responseObj = $this->processAuthRequest($transferObject);
+                break;
+            case self::REFUND:
+            case self::AUTHORIZATION_CANCEL:
+            case self::LIST_CAPTURE:
+            case self::LIST_FETCH:
+            case self::LIST_DELETE:
+                $responseObj = $this->processRequest($transferObject);
+                break;
+            default:
+                throw new \InvalidArgumentException(sprintf('Unknown operation [%s]', $this->operation));
+        }
+
+        if ($responseObj instanceof DataObject) {
+            $response['response'] = $responseObj->getData('response') ?: '';
+            $response['status'] = $responseObj->getData('status') ?: '';
+            $response['reason'] = $responseObj->getData('reason') ?: '';
+        }
+
+        $this->logData($response);
+
+        return $response;
+    }
+
+    /**
+     * @param TransferInterface $transferObject
+     * @return DataObject
+     */
+    protected function processAuthRequest($transferObject)
+    {
+        $responseObject = new \Magento\Framework\DataObject();
+        $responseObject->setData('response', $this->getResponseData($transferObject));
+        return $responseObject;
+    }
+
+    /**
+     * @param TransferInterface $transfer
+     * @return array|mixed
+     */
+    private function getResponseData(TransferInterface $transfer)
+    {
+        $headers = $transfer->getHeaders();
+
+        if (isset($headers[Config::TXN_ID])) {
+            return [Config::TXN_ID => $headers[Config::TXN_ID]];
+        }
+
+        return [];
+    }
+
+    /**
+     * Validate payoneer request data
+     *
+     * @return bool
+     */
+    public function validateRequest()
+    {
+        $isValid = true;
+        foreach ($this->mandatoryFields as $mandatoryField) {
+            switch ($mandatoryField) {
+                case 'payment':
+                    $isValid = $this->mandatoryFieldsExists($this->mandatoryFieldsPayment, 'payment');
+                    break;
+                case 'customer':
+                    $isValid = $this->mandatoryFieldsExists($this->mandatoryFieldsCustomer, 'customer');
+                    break;
+                default:
+                    if (is_array($this->requestData) && !isset($this->requestData[$mandatoryField]) ||
+                        (is_array($this->requestData)
+                            && isset($this->requestData[$mandatoryField])
+                            && $this->requestData[$mandatoryField] == '')) {
+                        $this->logData([$mandatoryField . ' must not be empty']);
+                        return false;
+                    }
+            }
+            if (!$isValid) {
+                return false;
+            }
+        }
+        return $isValid;
+    }
+
+    /**
+     * Check if mandatory fields exists
+     *
+     * @param array <mixed> $mandatoryFields
+     * @param string $objectName
+     * @return bool
+     */
+    public function mandatoryFieldsExists($mandatoryFields, $objectName)
+    {
+        foreach ($mandatoryFields as $mandatoryField) {
+            if (is_array($this->requestData) && !isset($this->requestData[$objectName][$mandatoryField])) {
+                $this->logData([$objectName . '.' . $mandatoryField . ' must not be empty']);
+                return false;
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Log data to payoneer.log
+     * @param array <mixed> $result
+     * @return void
+     */
+    public function logData($result)
+    {
+        if ((bool)$this->config->getValue('debug') == true) {
+            $this->logger->debug([$result]);
+        }
+    }
+
+    /**
+     * Process the api request.
+     *
+     * @param TransferInterface $transferObject
+     * @return DataObject <mixed> | DataObject
+     */
+    public function processRequest($transferObject)
+    {
+        $credentials = [];
+        $credentials['merchantCode'] = $transferObject->getAuthUsername();
+        $credentials['apiKey'] = $transferObject->getAuthPassword();
+
+        $clientConfigs = $transferObject->getClientConfig();
+        $credentials['hostName'] = $clientConfigs['host_name'];
+
+        $data = $transferObject->getBody();
+
+        if ((bool)$this->config->getValue('debug') == true) {
+            $this->logger->debug(['request' => $data]);
+        }
+        return $this->request->send(
+            $transferObject->getMethod(),
+            $transferObject->getUri(),
+            $credentials,
+            $data
+        );
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/ListCaptureTransferFactory.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http;
+
+use Magento\Payment\Gateway\Data\PaymentDataObjectInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class ListCaptureTransferFactory
+ *
+ * Builds gateway transfer object
+ */
+class ListCaptureTransferFactory extends TransferFactory
+{
+    /**
+     * @inheritDoc
+     */
+    protected function getApiUri(PaymentDataObjectInterface $payment)
+    {
+        $additionalInformation = $payment->getPayment()->getAdditionalInformation();
+        $longId = $additionalInformation['longId'];
+
+        return sprintf(
+            Config::CAPTURE_END_POINT,
+            $longId
+        );
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/ListFetchTransferFactory.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http;
+
+use Magento\Payment\Gateway\Data\PaymentDataObjectInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class ListFetchTransferFactory
+ *
+ * Builds gateway transfer object
+ */
+class ListFetchTransferFactory extends TransferFactory
+{
+    /**
+     * @inheritDoc
+     */
+    protected function getApiUri(PaymentDataObjectInterface $payment)
+    {
+        $additionalInformation = $payment->getPayment()->getAdditionalInformation();
+        $longId = $additionalInformation['longId'];
+
+        return 'api/charges/' . $longId;
+    }
+
+    /**
+     * Return the method
+     *
+     * @return string
+     */
+    protected function getMethod()
+    {
+        return Config::METHOD_GET;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/MagentoTransferFactory.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http;
+
+use Magento\Payment\Gateway\Http\TransferBuilder;
+use Magento\Payment\Gateway\Http\TransferFactoryInterface;
+use Magento\Payment\Gateway\Http\TransferInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class MagentoTransferFactory
+ *
+ * Builds gateway transfer object
+ */
+class MagentoTransferFactory implements TransferFactoryInterface
+{
+    /**
+     * @var TransferBuilder
+     */
+    protected $transferBuilder;
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * @param TransferBuilder $transferBuilder
+     * @param Config $config
+     */
+    public function __construct(
+        TransferBuilder $transferBuilder,
+        Config $config
+    ) {
+        $this->transferBuilder = $transferBuilder;
+        $this->config = $config;
+    }
+
+    /**
+     * Builds gateway transfer object
+     *
+     * @param array <mixed> $request
+     * @return TransferInterface
+     */
+    public function create(array $request)
+    {
+        return $this->transferBuilder
+            ->setBody($request)
+            ->setMethod(Config::METHOD_POST)
+            ->setHeaders(
+                [
+                    Config::TXN_ID => $request[Config::TXN_ID]
+                ]
+            )
+            ->build();
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/RefundTransferFactory.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http;
+
+use Magento\Payment\Gateway\Data\PaymentDataObjectInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class RefundTransferFactory
+ *
+ * Builds refund transfer object
+ */
+class RefundTransferFactory extends TransferFactory
+{
+    /**
+     * @inheritDoc
+     */
+    protected function getApiUri(PaymentDataObjectInterface $payment)
+    {
+        $payment = $payment->getPayment();
+        $captureResponse = $payment->getAdditionalInformation('capture_response');
+
+        if ($captureResponse) {
+            $longId = isset($captureResponse['longId']) ? $captureResponse['longId'] : null;
+        } else {
+            $longId = $payment->getAdditionalInformation('longId');
+        }
+        return sprintf(
+            Config::REFUND_END_POINT,
+            $longId
+        );
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/TransferFactory.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http;
+
+use Magento\Payment\Gateway\Data\PaymentDataObjectInterface;
+use Magento\Payment\Gateway\Http\TransferBuilder;
+use Magento\Payment\Gateway\Http\TransferInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class TransferFactory
+ *
+ * Builds gateway transfer object
+ */
+class TransferFactory implements TransferFactoryInterface
+{
+    /**
+     * @var TransferBuilder
+     */
+    protected $transferBuilder;
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * @var string
+     */
+    protected $method;
+
+    /**
+     * @param TransferBuilder $transferBuilder
+     * @param Config $config
+     * @param string $method
+     */
+    public function __construct(
+        TransferBuilder $transferBuilder,
+        Config $config,
+        $method
+    ) {
+        $this->transferBuilder = $transferBuilder;
+        $this->config = $config;
+        $this->method = $method;
+    }
+
+    /**
+     * Builds gateway transfer object
+     *
+     * @param array <mixed> $request
+     * @param PaymentDataObjectInterface $payment
+     * @return TransferInterface
+     */
+    public function create(array $request, PaymentDataObjectInterface $payment)
+    {
+        $merchantCode = $this->config->getValue('merchant_gateway_key');
+        $apiKey = $this->config->getCredentials('api_key');
+        $hostName = $this->config->getCredentials('host_name');
+
+        return $this->transferBuilder
+            ->setBody($request)
+            ->setAuthUsername($merchantCode)
+            ->setAuthPassword($apiKey)
+            ->setMethod($this->getMethod())
+            ->setUri($this->getApiUri($payment))
+            ->setHeaders(
+                $this->config->prepareHeaders($merchantCode, $apiKey)
+            )->setClientConfig(['host_name' => $hostName])
+            ->build();
+    }
+
+    /**
+     * Return the api uri
+     *
+     * @param PaymentDataObjectInterface $payment
+     * @return string
+     */
+    protected function getApiUri(PaymentDataObjectInterface $payment)
+    {
+        if ($this->method == Config::METHOD_POST) {
+            return Config::LIST_END_POINT;
+        } else {
+            $additionalInformation = $payment->getPayment()->getAdditionalInformation();
+            $listId = isset($additionalInformation['listId']) ? $additionalInformation['listId'] : null;
+
+            return sprintf(
+                Config::LIST_UPDATE_END_POINT,
+                $listId
+            );
+        }
+    }
+
+    /**
+     * Return the method
+     *
+     * @return string
+     */
+    protected function getMethod()
+    {
+        return $this->method;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Http/TransferFactoryInterface.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Http;
+
+use Magento\Payment\Gateway\Data\PaymentDataObjectInterface;
+use Magento\Payment\Gateway\Http\TransferInterface;
+
+interface TransferFactoryInterface
+{
+    /**
+     * Build gateway transfer object
+     *
+     * @param array <mixed> $request
+     * @param PaymentDataObjectInterface $payment
+     *
+     * @return TransferInterface
+     */
+    public function create(array $request, PaymentDataObjectInterface $payment);
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/QuoteAdapter.php

+<?php
+namespace Payoneer\OpenPaymentGateway\Gateway;
+
+use Magento\Payment\Gateway\Data\Quote\AddressAdapterFactory;
+use Magento\Quote\Api\Data\CartInterface;
+use Magento\Quote\Api\Data\CartItemInterface;
+use Magento\Quote\Model\Quote;
+use Magento\Quote\Model\Quote\Address;
+use Magento\Payment\Gateway\Data\Quote\QuoteAdapter as MagentoQuoteAdapter;
+
+/**
+ * Class QuoteAdapter
+ * Gets the details from quote
+ */
+class QuoteAdapter extends MagentoQuoteAdapter
+{
+    /** @var Quote */
+    protected $quote;
+
+    /**
+     * QuoteAdapter constructor.
+     * @param CartInterface $quote
+     * @param AddressAdapterFactory $addressAdapterFactory
+     */
+    public function __construct(CartInterface $quote, AddressAdapterFactory $addressAdapterFactory)
+    {
+        parent::__construct($quote, $addressAdapterFactory);
+        $this->quote = $quote;/** @phpstan-ignore-line */
+    }
+
+    /**
+     * Get remote ip
+     * @return string|null
+     */
+    public function getRemoteIp()
+    {
+        return $this->quote->getRemoteIp();
+    }
+
+    /**
+     * Get shipping amount
+     * @return float
+     */
+    public function getShippingAmount()
+    {
+        return $this->getAddressModel()->getBaseShippingAmount();
+    }
+
+    /**
+     * Get tax amount
+     * @return float
+     */
+    public function getTaxAmount()
+    {
+        return $this->getAddressModel()->getTaxAmount();
+    }
+
+    /**
+     * Get shipping amount inclusive tax
+     * @return float
+     */
+    public function getShippingAmountInclTax()
+    {
+        return $this->getAddressModel()->getBaseShippingInclTax();
+    }
+
+    /**
+     * Get discount amount
+     * @return float
+     */
+    public function getDiscountAmount()
+    {
+        return $this->getAddressModel()->getBaseDiscountAmount();
+    }
+
+    /**
+     * @return Address
+     */
+    protected function getAddressModel()
+    {
+        return $this->quote->isVirtual() ? $this->quote->getBillingAddress() : $this->quote->getShippingAddress();
+    }
+
+    /**
+     * Get quote items
+     * @return array|CartItemInterface[]|null
+     */
+    public function getItems()
+    {
+        $items = parent::getItems();
+        if (!$items) {
+            $items = $this->quote->getAllItems();
+        }
+
+        return $items;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/AddressDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Checkout\Model\Session;
+use Magento\Payment\Gateway\Data\AddressAdapterInterface;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class AddressDataBuilder
+ * Class to build address data
+ */
+class AddressDataBuilder implements BuilderInterface
+{
+    /**
+     * Billing address data constants
+     */
+    const FIRST_NAME    =   'firstname';
+    const LAST_NAME     =   'lastname';
+    const MIDDLE_NAME   =   'middlename';
+    const EMPTY_STRING  =   '';
+    const SHIPPING      =   'shipping';
+    const BILLING       =   'billing';
+
+    /**
+     * @var Session
+     */
+    private $checkoutSession;
+
+    /**
+     * @var Config
+     */
+    private $config;
+
+    /**
+     * @param Session $checkoutSession
+     * @param Config $config
+     */
+    public function __construct(
+        Session $checkoutSession,
+        Config $config
+    ) {
+        $this->checkoutSession = $checkoutSession;
+        $this->config = $config;
+    }
+
+    /**
+     * Builds address data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+
+        $order = $payment->getOrder();
+        $billingAddress = $order->getBillingAddress();
+        $shippingAddress = $order->getShippingAddress();
+        $billingAddressChanged = false;
+        $address = isset($buildSubject['address']) ? $buildSubject['address'] : null;
+        if ($address) {
+            $billingAddress = $address;
+            $billingAddressChanged = true;
+        }
+
+        $shippingAddressCountryId = $shippingAddress ? $shippingAddress->getCountryId() : null;
+        if ($shippingAddressCountryId) {
+            $this->checkoutSession->setShippingCountryId($shippingAddressCountryId);
+        }
+
+        return [
+            Config::CUSTOMER => [
+                Config::ADDRESSES => [
+                    Config::SHIPPING => $shippingAddress ? $this->getAddressData($shippingAddress, self::SHIPPING) : [],
+                    Config::BILLING => $billingAddressChanged ?
+                        $this->getNewBillingAddress($billingAddress) :
+                        $this->getAddressData($billingAddress, self::BILLING)
+                ]
+            ]
+        ];
+    }
+
+    /**
+     * Gets address details
+     *
+     * @param AddressAdapterInterface $address
+     * @param string $type
+     * @return array <mixed>
+     */
+    public function getAddressData($address, $type)
+    {
+        return [
+            Config::STREET => $address->getStreetLine1() ?: null,
+            Config::HOUSE_NUMBER => $address->getStreetLine2(),
+            Config::ZIP => $address->getPostcode(),
+            Config::CITY => $address->getCity(),
+            Config::STATE => $address->getRegionCode(),
+            Config::COUNTRY => $this->getCountryId($address, $type),
+            Config::NAME => [
+                Config::FIRST_NAME => $address->getFirstname(),
+                Config::MIDDLE_NAME => $address->getMiddlename(),
+                Config::LAST_NAME => $address->getLastname()
+            ]
+        ];
+    }
+
+    /**
+     * @param AddressAdapterInterface $address
+     * @param string $type
+     * @return string
+     */
+    public function getCountryId($address, $type)
+    {
+        $countryId = $address->getCountryId();
+        if (!$countryId) {
+            switch ($type) {
+                case self::SHIPPING:
+                    $countryId = $this->checkoutSession->getShippingCountryId() ?: $this->config->getCountryByStore();
+                    break;
+                case self::BILLING:
+                    $countryId = $this->checkoutSession->getBillingCountryId() ?: $this->config->getCountryByStore();
+                    break;
+            }
+        }
+        return $countryId;
+    }
+
+    /**
+     * Build new billing address data
+     * @param array <mixed> $billingAddress
+     * @return array <mixed>
+     */
+    public function getNewBillingAddress($billingAddress)
+    {
+        $billingAddressCountryId = isset($billingAddress[Config::COUNTRY_ID]) ?
+            $billingAddress[Config::COUNTRY_ID] : $this->checkoutSession->getBillingCountryId();
+
+        return [
+            Config::STREET => isset($billingAddress[Config::STREET][0]) ?
+                $billingAddress[Config::STREET][0] : self::EMPTY_STRING,
+            Config::HOUSE_NUMBER => isset($billingAddress[Config::STREET][1]) ?
+                $billingAddress[Config::STREET][1] : self::EMPTY_STRING,
+            Config::ZIP => isset($billingAddress[Config::POSTCODE]) ?
+                $billingAddress[Config::POSTCODE] : self::EMPTY_STRING,
+            Config::CITY => isset($billingAddress[Config::CITY]) ?
+                $billingAddress[Config::CITY] : self::EMPTY_STRING,
+            Config::STATE => isset($billingAddress[Config::REGION]) ?
+                $billingAddress[Config::REGION] : self::EMPTY_STRING,
+            Config::COUNTRY => $billingAddressCountryId ?: $this->config->getCountryByStore(),
+            Config::NAME => [
+                Config::FIRST_NAME => isset($billingAddress[self::FIRST_NAME]) ?
+                    $billingAddress[self::FIRST_NAME] : self::EMPTY_STRING,
+                Config::MIDDLE_NAME => isset($billingAddress[self::MIDDLE_NAME]) ?
+                    $billingAddress[self::MIDDLE_NAME] : self::EMPTY_STRING,
+                Config::LAST_NAME => isset($billingAddress[self::LAST_NAME]) ?
+                    $billingAddress[self::LAST_NAME] : self::EMPTY_STRING
+            ]
+        ];
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/AdminTransactionIDDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class AdminTransactionIDDataBuilder
+ * Builds transaction request
+ */
+class AdminTransactionIDDataBuilder implements BuilderInterface
+{
+    /**
+     * Builds transaction id
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+        return [
+            Config::TRANSACTION_ID => $payment->getOrder()->getId() . strtotime('now')
+        ];
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/BaseRequestDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Framework\App\RequestInterface as Request;
+use Magento\Framework\Module\ModuleListInterface;
+use Magento\Payment\Gateway\Data\PaymentDataObjectInterface;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\Source\Fields;
+
+/**
+ * Class BaseRequestDataBuilder
+ * Builds base request data
+ */
+class BaseRequestDataBuilder implements BuilderInterface
+{
+    /**
+     * @var Config
+     */
+    private $config;
+
+    /**
+     * @var Request
+     */
+    private $request;
+
+    /**
+     * @var ModuleListInterface
+     */
+    private $moduleList;
+
+    /**
+     * @param Config $config
+     * @param Request $request
+     */
+    public function __construct(
+        Config $config,
+        Request $request,
+        ModuleListInterface $moduleList
+    ) {
+        $this->config = $config;
+        $this->request = $request;
+        $this->moduleList = $moduleList;
+    }
+
+    /**
+     * Builds base request data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+
+        return [
+            Config::TRANSACTION_ID  => $payment->getPayment()->getAdditionalInformation(Config::TXN_ID),
+            Config::COUNTRY         => $this->getCountryId($payment),
+            Config::INTEGRATION     => $this->getPaymentFlow(),
+            Config::DIVISION        => $this->config->getValue('environment') == Fields::ENVIRONMENT_SANDBOX_VALUE
+                ? $this->config->getValue('sandbox_store_code')
+                : $this->config->getValue('live_store_code'),
+            Config::ALLOW_DELETE    => true,
+
+            //system attributes
+            "system"                => [
+                "type"              => "SHOP_PLATFORM",
+                "code"              => "MAGENTO",
+                "version"           => $this->moduleList->getOne('Payoneer_OpenPaymentGateway')['setup_version']
+            ]
+        ];
+    }
+
+    /**
+     * @param PaymentDataObjectInterface $payment
+     * @return string
+     */
+    private function getCountryId($payment)
+    {
+        $order = $payment->getOrder();
+
+        //use country of shipping address if it exists, else billing address or store country
+        $shippingAddress = $order->getShippingAddress();
+        if (isset($shippingAddress) && $shippingAddress->getCountryId()) {
+            $countryId = $shippingAddress->getCountryId();
+        } else {
+            $billingAddress = $order->getBillingAddress();
+            if (isset($billingAddress) && $billingAddress->getCountryId()) {
+                $countryId = $billingAddress->getCountryId();
+            } else {
+                $countryId = $this->config->getCountryByStore();
+            }
+        }
+        return $countryId;
+    }
+
+    /**
+     * Build payment flow from request
+     *
+     * @return string
+     */
+    private function getPaymentFlow()
+    {
+        $integration = $this->request->getParam(Config::INTEGRATION);
+        if ($integration == Config::INTEGRATION_HOSTED) {
+            return Config::HOSTED;
+        }
+        if ($integration == Config::INTEGRATION_EMBEDDED) {
+            return Config::SELECT_NATIVE;
+        }
+        return $this->config->getValue(Config::PAYMENT_FLOW);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/CallBackDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Checkout\Model\Session;
+use Magento\Framework\UrlInterface;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class CallBackBuilder
+ * Builds Callback array
+ */
+class CallBackDataBuilder implements BuilderInterface
+{
+    /**
+     * @var UrlInterface
+     */
+    private $urlBuilder;
+
+    /**
+     * @var Session
+     */
+    private $checkoutSession;
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * CallBackBuilder constructor.
+     * @param UrlInterface $urlBuilder
+     * @param Session $checkoutSession
+     * @param Config $config
+     */
+    public function __construct(
+        UrlInterface $urlBuilder,
+        Session $checkoutSession,
+        Config $config
+    ) {
+        $this->urlBuilder = $urlBuilder;
+        $this->checkoutSession = $checkoutSession;
+        $this->config = $config;
+    }
+
+    /**
+     * Builds callback data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+        $token = $payment->getPayment()->getAdditionalInformation(Config::TOKEN);
+        $notificationToken = $payment->getPayment()->getAdditionalInformation(Config::TOKEN_NOTIFICATION);
+        $orderId = $payment->getOrder()->getOrderIncrementId();
+        $cartId = $this->getQuoteIdFromSession();
+
+        $successParams = ['cart_id' => $cartId, 'token' => $token];
+        $cancelParams = ['cart_id' => $cartId, 'error' => true];
+
+        return [
+            Config::CALLBACK => [
+                Config::RETURN_URL => $this->urlBuilder->getUrl(Config::RETURN_URL_PATH, $successParams),
+                Config::CANCEL_URL => $this->urlBuilder->getUrl(Config::CANCEL_URL_PATH, $cancelParams),
+                Config::NOTIFICATION_URL => $this->getNotificationUrl($orderId, $notificationToken)
+            ]
+        ];
+    }
+
+    /**
+     * @param string $orderId
+     * @param mixed $token
+     * @return string
+     */
+    public function getNotificationUrl($orderId, $token)
+    {
+        $configUrl = $this->config->getValue('notification_url');
+        if ($configUrl) {
+            $configUrl = $configUrl . '/order_id/' . $orderId . '/token/' . $token;
+        } else {
+            $configUrl =  $this->urlBuilder->getUrl(
+                Config::NOTIFICATION_URL_PATH,
+                ['order_id' => $orderId, 'token' => $token]
+            );
+        }
+        return $configUrl;
+    }
+
+    /**
+     * Gets quote id from the checkout session
+     * @return int|null
+     */
+    public function getQuoteIdFromSession()
+    {
+        $quoteId = null;
+        if ($this->checkoutSession->hasQuote()) {
+            $quoteId = $this->checkoutSession->getQuoteId();
+        }
+        return $quoteId;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/CustomerDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Checkout\Model\Session;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\Helper;
+
+/**
+ * Class CustomerDataBuilder
+ * Builds customer data
+ */
+class CustomerDataBuilder implements BuilderInterface
+{
+    /**
+     * @var Helper
+     */
+    private $helper;
+
+    /**
+     * @var Session
+     */
+    private $checkoutSession;
+
+    /**
+     * @param Helper $helper
+     * @param Session $checkoutSession
+     */
+    public function __construct(
+        Helper $helper,
+        Session $checkoutSession
+    ) {
+        $this->helper = $helper;
+        $this->checkoutSession = $checkoutSession;
+    }
+
+    /**
+     * Builds customer data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+
+        $order = $payment->getOrder();
+        $billingAddress = $order->getBillingAddress();
+
+        $registrationId = null;
+        $number = null;
+        $customerId = $order->getCustomerId();
+        if ($customerId) {
+            $registrationId = $this->helper->getRegistrationId($customerId);
+            $number = $customerId;
+        } else {
+            $number = $billingAddress ? $billingAddress->getTelephone() : null;
+        }
+
+        $customerEmail = $billingAddress ? $billingAddress->getEmail() : null;
+        if (!$customerEmail) {
+            $customerEmail = $this->checkoutSession->getPayoneerCustomerEmail();
+        }
+
+        $customerData = [
+            Config::CUSTOMER    => [
+                Config::NUMBER  => $number,
+                Config::EMAIL   => $customerEmail,
+                Config::COMPANY => [
+                    Config::NAME    => $billingAddress ? $billingAddress->getCompany() : null,
+                ],
+                Config::NAME    => [
+                    Config::FIRST_NAME  => $billingAddress ? $billingAddress->getFirstname() : null,
+                    Config::MIDDLE_NAME => $billingAddress ? $billingAddress->getMiddlename() : null,
+                    Config::LAST_NAME   => $billingAddress ? $billingAddress->getLastname() : null
+                ]
+            ]
+        ];
+
+        if ($registrationId) {
+            $customerData[Config::CUSTOMER][Config::REGISTRATION] = [
+                Config::ID  => $registrationId
+            ];
+        }
+
+        return $customerData;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/ItemsDataBuilder.php

+<?php
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Payment\Gateway\Data\OrderAdapterInterface;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Magento\Sales\Model\Order\Item;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Gateway\QuoteAdapter as PayoneerQuoteAdapter;
+use Payoneer\OpenPaymentGateway\Model\Helper;
+
+/**
+ * Class ItemsDataBuilder
+ * Build Item Data
+ */
+class ItemsDataBuilder implements BuilderInterface
+{
+    const ADJUSTMENTS = 'Total Adjustments';
+
+    /**
+     * @var Helper
+     */
+    private $helper;
+
+    /**
+     * @param Helper $helper
+     */
+    public function __construct(
+        Helper $helper
+    ) {
+        $this->helper = $helper;
+    }
+
+    /**
+     * Builds items data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+
+        $order = $payment->getOrder();
+
+        $totalItemsCount = isset($buildSubject['totalItemsCount'])
+            ? $buildSubject['totalItemsCount'] : 0;
+
+        if ($order->getItems() && $totalItemsCount > 0) {
+            $items = $this->buildItems($order);
+            return [
+                Config::PRODUCTS => $items
+            ];
+        } else {
+            return [];
+        }
+    }
+
+    /**
+     * Build items
+     *
+     * @param OrderAdapterInterface $order
+     * @return array <mixed>
+     */
+    protected function buildItems($order)
+    {
+        $result = [];
+        /** @var Item[] $items */
+        $items = $order->getItems();
+        foreach ($items as $item) {
+            $result[] = [
+                Config::SKU             =>  $item->getSku(),
+                Config::NAME            =>  $item->getName(),
+                Config::QUANTITY        =>  $item->getData('qty'),
+                Config::CURRENCY        =>  $order->getCurrencyCode(),
+                Config::AMOUNT          =>  $this->helper->formatNumber($item->getBaseRowTotal()),
+                Config::NET_AMOUNT      =>  $this->helper->formatNumber($item->getBaseRowTotal()),
+                Config::TAX_AMOUNT      =>  $this->helper->formatNumber($item->getBaseTaxAmount()),
+                Config::TAX_PERCENT     =>  $this->helper->formatNumber($item->getBaseRowTotalInclTax())
+            ];
+        }
+        if ($order instanceof PayoneerQuoteAdapter) {
+            $totalAdjustments = 0.00;
+            if ($order->getShippingAmountInclTax() > 0) {
+                $totalAdjustments += $order->getShippingAmountInclTax();
+            }
+            if ($order->getDiscountAmount() < 0) {
+                $totalAdjustments += $order->getDiscountAmount();
+            }
+            if ($order->getTaxAmount() > 0) {
+                $totalAdjustments += $order->getTaxAmount();
+            }
+            $result[] = [
+                Config::NAME => self::ADJUSTMENTS,
+                Config::AMOUNT => number_format($totalAdjustments, 2)
+            ];
+        }
+
+        return $result;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/PaymentDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class PaymentDataBuilder
+ * Builds payment data
+ */
+class PaymentDataBuilder implements BuilderInterface
+{
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * @param Config $config
+     */
+    public function __construct(
+        Config $config
+    ) {
+        $this->config = $config;
+    }
+
+    /**
+     * Builds payment data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+        $order = $payment->getOrder();
+
+        return [
+            Config::PAYMENT => [
+                Config::AMOUNT      => number_format($buildSubject[Config::AMOUNT], 2),
+                Config::CURRENCY    => $order->getCurrencyCode(),
+                Config::REFERENCE   => $this->config->getValue('order_reference_message'),
+                Config::INVOICE_ID  => $order->getId()
+            ]
+        ];
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/PreselectionBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Model\Adminhtml\Source\Fields;
+
+/**
+ * Class PreselectionBuilder
+ * Builds 'preselection' array
+ */
+class PreselectionBuilder implements BuilderInterface
+{
+    /**
+     * Preference array constants
+     */
+    const DEFERRED = 'DEFERRED';
+    const NON_DEFERRED = 'NON_DEFERRED';
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * PreselectionBuilder constructor.
+     * @param Config $config
+     */
+    public function __construct(
+        Config $config
+    ) {
+        $this->config = $config;
+    }
+
+    /**
+     * Builds preselection data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        return [
+            Config::PRESELECTION => [
+                Config::DEFERRAL => $this->config->getValue('payment_action') == Fields::AUTHORIZE
+                    ? self::DEFERRED
+                    : self::NON_DEFERRED
+            ]
+        ];
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/StyleDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Framework\UrlInterface;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Magento\Framework\App\RequestInterface as Request;
+
+/**
+ * Class StyleDataBuilder
+ * Builds Style data array
+ */
+class StyleDataBuilder implements BuilderInterface
+{
+    /**
+     * @var Config
+     */
+    protected $config;
+    /**
+     * @var UrlInterface
+     */
+    private $urlBuilder;
+
+    /**
+     * @var Request
+     */
+    private $request;
+
+    /**
+     * @param UrlInterface $urlBuilder
+     * @param Config $config
+     * @param Request $request
+     */
+    public function __construct(
+        UrlInterface $urlBuilder,
+        Config $config,
+        Request $request
+    ) {
+        $this->urlBuilder = $urlBuilder;
+        $this->config = $config;
+        $this->request = $request;
+    }
+
+    /**
+     * Builds style data
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+
+        $styleData = [
+            Config::STYLE => [
+                Config::HOSTED_VERSION => Config::VERSION_V4,
+                Config::LANGUAGE => $this->config->getStoreLocale()
+            ]
+        ];
+
+        if ($this->isHostedIntegration()) {
+            return $styleData;
+        } else {
+            $styleDataValues = $this->config->getStyleConfig();
+            $styleData[Config::STYLE]['resolution'] = Config::RESOLUTION_1X;
+            if (isset($styleDataValues['background-color'])) {
+                $styleData[Config::STYLE]['primaryColor'] = $styleDataValues['background-color'];
+            }
+            $styleData[Config::STYLE]['cssOverride'] =
+            $this->urlBuilder->getUrl(Config::EMBEDDED_STYLE_PATH);
+        }
+
+        return $styleData;
+    }
+
+    /**
+     * @return bool
+     */
+    private function isHostedIntegration()
+    {
+        $integration = $this->request->getParam(Config::INTEGRATION);
+        if ($integration  == Config::INTEGRATION_HOSTED) {
+            return true;
+        }
+        if ($this->config->getValue(Config::PAYMENT_FLOW) == Config::HOSTED) {
+            return true;
+        }
+        return false;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Request/TransactionIDDataBuilder.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Request;
+
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Request\BuilderInterface;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * Class TransactionIDDataBuilder
+ * Builds magento transaction request
+ */
+class TransactionIDDataBuilder implements BuilderInterface
+{
+    /**
+     * Builds transaction id
+     *
+     * @param array <mixed> $buildSubject
+     * @return array <mixed>
+     */
+    public function build(array $buildSubject)
+    {
+        $payment = SubjectReader::readPayment($buildSubject);
+
+        return [
+            Config::TXN_ID => $payment->getPayment()->getAdditionalInformation(Config::TXN_ID)
+        ];
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Response/PayoneerResponseHandler.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Response;
+
+use Magento\Checkout\Model\Session;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Response\HandlerInterface;
+use Magento\Sales\Model\Order\Payment;
+use Magento\Sales\Model\Order\Payment\Transaction;
+
+/**
+ * Class PayoneerResponseHandler
+ *
+ * Payoneer gateway response handler
+ */
+class PayoneerResponseHandler implements HandlerInterface
+{
+    const ADDITIONAL_INFO_KEY_REFUND_RESPONSE = 'refund_response';
+    const ADDITIONAL_INFO_KEY_PARTIAL_REFUND_RESPONSE = 'partial_refund_response';
+    const ADDITIONAL_INFO_KEY_CAPTURE_RESPONSE = 'capture_response';
+    const ADDITIONAL_INFO_KEY_AUTH_CANCEL_RESPONSE = 'auth_cancel_response';
+
+    const AUTH_CANCEL_STATUS_NODE = 'auth_cancel_status';
+    const AUTH_CAPTURE_STATUS_NODE = 'capture_status';
+    const REFUND_TXN_TYPE =   'refund';
+
+    /**
+     * @var SubjectReader
+     */
+    private $subjectReader;
+
+    /**
+     * @var mixed|string
+     */
+    private $additionalInfoKey;
+
+    /**
+     * @var mixed|string
+     */
+    private $actionSuccessResponseKey;
+
+    /**
+     * @var mixed
+     */
+    private $transactionType;
+
+    /**
+     * @var Session
+     */
+    private $session;
+
+    /**
+     * PayoneerResponseHandler constructor.
+     *
+     * @param SubjectReader $subjectReader
+     * @param Session $checkoutSession
+     * @param string|mixed $additionalInfoKey
+     * @param string|mixed $actionSuccessResponseKey
+     * @param string $transactionType
+     */
+    public function __construct(
+        SubjectReader $subjectReader,
+        Session $checkoutSession,
+        $additionalInfoKey = '',
+        $actionSuccessResponseKey = '',
+        $transactionType = ''
+    ) {
+        $this->subjectReader = $subjectReader;
+        $this->session = $checkoutSession;
+        $this->additionalInfoKey = $additionalInfoKey;
+        $this->actionSuccessResponseKey = $actionSuccessResponseKey;
+        $this->transactionType = $transactionType;
+    }
+
+    /**
+     * Handle the response.
+     *
+     * @param array <mixed> $handlingSubject
+     * @param array <mixed> $response
+     * @return void
+     * @throws LocalizedException
+     */
+    public function handle(array $handlingSubject, array $response)
+    {
+        $paymentDO = $this->subjectReader->readPayment($handlingSubject);
+
+        /** @var Payment $orderPayment */
+        $orderPayment = $paymentDO->getPayment();
+
+        if ($this->session->getFetchNotificationResponse()) {
+            $additionalInfo = $this->session->getFetchNotificationResponse();
+            $longId = $additionalInfo['longId'];
+            $orderPayment->setTransactionId($longId . '- refund');
+        } else {
+            $additionalInfo = $this->buildAdditionalInfoDataFromResponse($response);
+            if ($this->transactionType == self::REFUND_TXN_TYPE) {
+                $longId = $response['response']['identification']['longId'];
+                $orderPayment->setTransactionId($longId . '- refund');
+            }
+        }
+        if ($this->additionalInfoKey == self::ADDITIONAL_INFO_KEY_REFUND_RESPONSE) {
+            $paymentAdditionalInfo = $orderPayment->getAdditionalInformation();
+
+            $refundResponse = isset($paymentAdditionalInfo[$this->additionalInfoKey]) ?
+                $paymentAdditionalInfo[$this->additionalInfoKey] : [];
+            $refundResponse[] = $additionalInfo;
+            $orderPayment->setAdditionalInformation(
+                $this->additionalInfoKey,
+                $refundResponse
+            );
+        } else {
+            $paymentAdditionalInfo = $orderPayment->getAdditionalInformation();
+            $mergedInfo = array_merge($paymentAdditionalInfo, $additionalInfo);
+            $orderPayment->setAdditionalInformation($mergedInfo);
+        }
+        $orderPayment->setTransactionAdditionalInfo(
+            Transaction::RAW_DETAILS,
+            $additionalInfo
+        );
+    }
+
+    /**
+     * Build the payment additional info data.
+     *
+     * @param array <mixed> $response
+     * @return array <mixed>
+     */
+    public function buildAdditionalInfoDataFromResponse($response)
+    {
+        $additionalInfo = [];
+        if (isset($response['response'])) {
+            $additionalInfo = [
+                'resultinfo' => $response['response']['resultInfo'],
+                'returncode_name' => $response['response']['returnCode']['name'],
+                'returncode_source' => $response['response']['returnCode']['source'],
+                'status_code' => $response['response']['status']['code'],
+                'status_reason' => $response['response']['status']['reason'],
+                'interaction_code' => $response['response']['interaction']['code'],
+                'interaction_reason' => $response['response']['interaction']['reason'],
+                'longId' => $response['response']['identification']['longId'],
+                'shortId' => $response['response']['identification']['shortId'],
+                'transactionId' => $response['response']['identification']['transactionId'],
+                'amount' => $response['response']['payment']['amount']
+            ];
+        }
+        if (!empty($this->actionSuccessResponseKey)) {
+            $additionalInfo[$this->actionSuccessResponseKey] = 'success';
+        }
+
+        return $additionalInfo;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Response/ResponseHandler.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Response;
+
+use Magento\Payment\Gateway\Response\HandlerInterface;
+use Magento\Sales\Model\Order\Payment;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Sales\Model\Order\Payment\Transaction;
+
+/**
+ * Class ResponseHandler
+ * Payoneer Response Handler
+ */
+class ResponseHandler implements HandlerInterface
+{
+    /**
+     * @var SubjectReader
+     */
+    private $subjectReader;
+
+    /**
+     * ResponseHandler constructor.
+     * @param SubjectReader $subjectReader
+     */
+    public function __construct(
+        SubjectReader $subjectReader
+    ) {
+        $this->subjectReader = $subjectReader;
+    }
+
+    /**
+     * Handles response
+     *
+     * @param array <mixed> $handlingSubject
+     * @param array <mixed> $response
+     * @return void
+     */
+    public function handle(array $handlingSubject, array $response)
+    {
+        $paymentDO = $this->subjectReader->readPayment($handlingSubject);
+
+        /** @var Payment $orderPayment */
+        $orderPayment = $paymentDO->getPayment();
+
+        $orderPayment->setTransactionId($response['response'][Config::TXN_ID]);
+        $orderPayment->setIsTransactionClosed(false);
+
+        $additionalInfo = $orderPayment->getAdditionalInformation();
+        $orderPayment->setTransactionAdditionalInfo(
+            Transaction::RAW_DETAILS,
+            $additionalInfo
+        );
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Gateway/Validator/ResponseValidator.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Gateway\Validator;
+
+use Magento\Payment\Gateway\Helper\SubjectReader;
+use Magento\Payment\Gateway\Validator\AbstractValidator;
+use Magento\Payment\Gateway\Validator\ResultInterface;
+use Magento\Payment\Gateway\Validator\ResultInterfaceFactory;
+
+/**
+ * Class ResponseValidator
+ * Payoneer Response Validator
+ */
+class ResponseValidator extends AbstractValidator
+{
+    const REFUND_PAID_OUT_STATUS        = 'paid_out';
+    const REFUND_PAID_OUT_PARTIAL       = 'paid_out_partial';
+    const CAPTURE_STATUS                = 'charged';
+    const REFUND_CREDITED               = 'refund_credited';
+    const AUTH_CANCEL_PENDING_STATUS    = 'pending';
+    const CANCELLATION_REQUESTED        = 'cancelation_requested';
+
+    const AUTH_CANCELLED_STATUS = 'canceled';
+
+    const PREAUTHORIZATION_CANCELLED = 'preauthorization_canceled';
+
+    /**
+     * @var bool
+     */
+    private $skipValidation;
+
+    /**
+     * @var mixed
+     */
+    private $successStatusCode;
+
+    /**
+     * @param ResultInterfaceFactory $resultFactory
+     * @param bool $skipValidation
+     * @param mixed $successStatusCode
+     * @return void
+     */
+    public function __construct(
+        ResultInterfaceFactory $resultFactory,
+        $skipValidation = false,
+        $successStatusCode = ''
+    ) {
+        parent::__construct($resultFactory);
+        $this->skipValidation = $skipValidation;
+        $this->successStatusCode = $successStatusCode;
+    }
+
+    /**
+     * Performs domain-related validation for business object
+     *
+     * @param array <mixed> $validationSubject
+     * @return ResultInterface
+     */
+    public function validate(array $validationSubject): ResultInterface
+    {
+        $response = SubjectReader::readResponse($validationSubject);
+        if ($this->skipValidation == true) {
+            return $this->createResult(true);
+        }
+        if ($response['status'] != 200) {
+            return $this->createResult(false, [$response['reason']]);
+        }
+
+        if (isset($response['response']['status']['code']) &&
+            $response['response']['status']['code'] != $this->successStatusCode
+        ) {
+            return $this->createResult(false, [$response['response']['resultInfo']]);
+        }
+        return $this ->createResult(true);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Http/PayoneerClient.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Http;
+
+use GuzzleHttp\Client;
+use GuzzleHttp\ClientFactory;
+use GuzzleHttp\Exception\GuzzleException;
+use GuzzleHttp\Psr7\Response;
+use GuzzleHttp\Psr7\ResponseFactory;
+use Magento\Framework\Webapi\Rest\Request;
+
+/**
+ * Class PayoneerClient to manage API client communication
+ */
+class PayoneerClient
+{
+
+    /**
+     * @var ResponseFactory
+     */
+    protected $responseFactory;
+
+    /**
+     * @var ClientFactory
+     */
+    protected $clientFactory;
+
+    /**
+     * @var array <mixed>
+     */
+    protected $handlers = [];
+
+    /**
+     * PayoneerClient constructor.
+     * @param ClientFactory $clientFactory
+     * @param ResponseFactory $responseFactory
+     */
+    public function __construct(
+        ClientFactory $clientFactory,
+        ResponseFactory $responseFactory
+    ) {
+        $this->clientFactory = $clientFactory;
+        $this->responseFactory = $responseFactory;
+    }
+
+    /**
+     * @param int|string $method
+     * @param string $hostname
+     * @param string $endpoint
+     * @param array <mixed> $options
+     * @return mixed
+     */
+    public function send(
+        $method,
+        $hostname,
+        $endpoint,
+        array $options = []
+    ) {
+        $response = $this->doRequest($hostname, $endpoint, $options, $method);
+        $responseBody = $response->getBody();
+        $responseBody->rewind();
+        $responseObject = new \Magento\Framework\DataObject();
+        $responseObject->setData('status', $response->getStatusCode());
+        $responseObject->setData('reason', $response->getReasonPhrase());
+        $responseObject->setData('response', json_decode($responseBody->getContents(), true));
+        return $responseObject;
+    }
+
+    /**
+     * Do API request with provided params
+     *
+     * @param string $hostname
+     * @param string $endpoint
+     * @param array <mixed> $options
+     * @param string|int $requestMethod
+     * @return mixed
+     */
+    private function doRequest(
+        $hostname,
+        $endpoint,
+        $options = [],
+        $requestMethod = Request::HTTP_METHOD_GET
+    ) {
+        try {
+            $uriEndpoint = $hostname . $endpoint;
+            $client = $this->clientFactory->create(['config' => [
+                'base_uri' => $hostname
+            ]]);
+
+            $response = $client->request(
+                (string)$requestMethod,
+                $uriEndpoint,
+                $options
+            );
+        } catch (GuzzleException $exception) {
+            $response = $this->responseFactory->create([
+                'status' => $exception->getCode(),
+                'reason' => $exception->getMessage()
+            ]);
+        }
+        return $response;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Logger/Handler.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Logger;
+
+use Magento\Framework\Filesystem\DriverInterface;
+use Magento\Framework\Logger\Handler\Base as BaseHandler;
+
+/**
+ * Logger handler class for Payoneer
+ */
+class Handler extends BaseHandler
+{
+    /**
+     * @var string
+     */
+    protected $fileName;
+
+    /**
+     * Handler constructor.
+     * @param DriverInterface $filesystem
+     * @param string $fileName
+     * @param null $filePath
+     * @throws \Exception
+     */
+    public function __construct(
+        DriverInterface $filesystem,
+        $fileName,
+        $filePath = null
+    ) {
+        $this->fileName = $fileName;
+        parent::__construct($filesystem, $filePath);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Logger/NotificationLogger.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Logger;
+
+use Payoneer\OpenPaymentGateway\Model\Helper;
+use Monolog\Handler\HandlerInterface;
+use Monolog\Logger;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+
+/**
+ * NotificationLogger class
+ * Log the notification related errors
+ */
+class NotificationLogger extends Logger
+{
+    /**
+     * @var array <mixed>
+     */
+    private $generalInfo = [];
+
+    /**
+     * @var Helper
+     */
+    private $helper;
+
+    /**
+     * @var Config
+     */
+    private $config;
+
+    /**
+     * NotificationLogger construct
+     *
+     * @param Helper $helper
+     * @param Config $config
+     * @param string             $name       The logging channel
+     * @param HandlerInterface[] $handlers   Optional stack of handlers
+     * @param callable[]         $processors Optional array of processors
+     * @return void
+     */
+    public function __construct(
+        Helper $helper,
+        Config $config,
+        $name,
+        array $handlers = [],
+        array $processors = []
+    ) {
+        parent::__construct($name, $handlers, $processors);
+        $this->helper = $helper;
+        $this->config = $config;
+    }
+
+    /**
+     * Adds a log record at the ERROR level.
+     *
+     * @param  string $message The log message
+     * @param  array <mixed>  $context The log context
+     * @return bool   Whether the record has been processed
+     */
+    public function addError($message, array $context = [])
+    {
+        if (!$this->config->isDebuggingEnabled()) {
+            return true;
+        }
+        $this->prepareGeneralInfo();
+        $message = $this->addGeneralInfoToMessage($message);
+        return $this->addRecord(static::ERROR, $message, $context);
+    }
+
+    /**
+     * Prepare the general info data for logging.
+     *
+     * @return void
+     */
+    private function prepareGeneralInfo()
+    {
+        if (empty($this->generalInfo)) {
+            $this->generalInfo = $this->helper->getProductMetaData();
+        }
+    }
+
+    /**
+     * Append the general info data before the message.
+     *
+     * @param string $message
+     * @return string
+     */
+    private function addGeneralInfoToMessage($message)
+    {
+        $finalMessage = '[';
+        foreach ($this->generalInfo as $key => $value) {
+            $finalMessage .= $key . '=' . $value . '|';
+        }
+        $finalMessage .= ']' . $message;
+
+        return $finalMessage;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/Adminhtml/Source/Fields.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Model\Adminhtml\Source;
+
+use Magento\Framework\Data\OptionSourceInterface;
+
+/**
+ * Class Fields
+ * Admin config fields
+ */
+class Fields implements OptionSourceInterface
+{
+    const ENVIRONMENT_PRODUCTION_LABEL  =   'Live';
+    const ENVIRONMENT_PRODUCTION_VALUE  =   'live';
+    const ENVIRONMENT_SANDBOX_LABEL     =   'Test';
+    const ENVIRONMENT_SANDBOX_VALUE     =   'test';
+    const HOSTED                        =   'HOSTED';
+    const SELECTIVE_NATIVE              =   'SELECTIVE_NATIVE';
+    const AUTHORIZE                     =   'authorize';
+    const CAPTURE                       =   'authorize_capture';
+    const STANDALONE                    =   'Standalone';
+    const EMBEDDED                      =   'Embedded';
+    const DIRECT_PAYMENT                =   'Direct payment';
+    const DEFERRED                      =   'Deferred';
+    const FONT_BOLD                     =   'bold';
+    const FONT_LIGHTER                  =   'lighter';
+    const FONT_NORMAL                   =   'normal';
+    const REGULAR                       =   'Regular';
+    const BOLD                          =   'Bold';
+    const LIGHTER                       =   'Lighter';
+    const LEFT                          =   'Left';
+    const RIGHT                         =   'Right';
+    const CENTER                        =   'Center';
+    const ALIGN_LEFT                    =   'left';
+    const ALIGN_RIGHT                   =   'right';
+    const ALIGN_CENTER                  =   'center';
+
+    /**
+     * Possible environment types
+     *
+     * @return array <mixed>
+     */
+    public function toOptionArray(): array
+    {
+        return [
+            [
+                'value' => self::ENVIRONMENT_SANDBOX_VALUE,
+                'label' => self::ENVIRONMENT_SANDBOX_LABEL
+            ],
+            [
+                'value' => self::ENVIRONMENT_PRODUCTION_VALUE,
+                'label' => self::ENVIRONMENT_PRODUCTION_LABEL
+            ]
+        ];
+    }
+
+    /**
+     * @return array <mixed>
+     */
+    public function fontWeight(): array
+    {
+        return [
+            [
+                'value' => self::FONT_LIGHTER,
+                'label' => self::LIGHTER,
+            ],
+            [
+                'value' => self::FONT_NORMAL,
+                'label' => self::REGULAR
+            ],
+            [
+                'value' => self::FONT_BOLD,
+                'label' => self::BOLD
+            ]
+        ];
+    }
+
+    /**
+     * @return array <mixed>
+     */
+    public function alignText(): array
+    {
+        return [
+            [
+                'value' => self::ALIGN_LEFT,
+                'label' => self::LEFT,
+            ],
+            [
+                'value' => self::ALIGN_RIGHT,
+                'label' => self::RIGHT
+            ],
+            [
+                'value' => self::ALIGN_CENTER,
+                'label' => self::CENTER
+            ]
+        ];
+    }
+
+    /**
+     * @return array <mixed>
+     */
+    public function paymentAction(): array
+    {
+        return [
+            [
+                'value' => self::AUTHORIZE,
+                'label' => self::DEFERRED
+            ],
+            [
+                'value' => self::CAPTURE,
+                'label' => self::DIRECT_PAYMENT
+            ]
+        ];
+    }
+
+    /**
+     * @return array <mixed>
+     */
+    public function paymentFlow(): array
+    {
+        return [
+            [
+                'value' => self::HOSTED,
+                'label' => self::STANDALONE
+            ],
+            [
+                'value' => self::SELECTIVE_NATIVE,
+                'label' => self::EMBEDDED
+            ]
+        ];
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/Adminhtml/TransactionService.php

+<?php
+namespace Payoneer\OpenPaymentGateway\Model\Adminhtml;
+
+use Exception;
+use Magento\Payment\Gateway\Command\CommandPoolInterface;
+use Magento\Payment\Gateway\Command\ResultInterface;
+use Magento\Payment\Gateway\Data\PaymentDataObjectFactory;
+use Magento\Sales\Model\Order;
+use Magento\Payment\Model\InfoInterface;
+
+/**
+ * Class TransactionService
+ *
+ * Process admin transactions api requests
+ */
+class TransactionService
+{
+    /**
+     * @var CommandPoolInterface
+     */
+    protected $commandPool;
+
+    /**
+     * @var PaymentDataObjectFactory
+     */
+    protected $paymentDataObjectFactory;
+
+    /**
+     * TransactionService constructor.
+     * @param CommandPoolInterface $commandPool
+     * @param PaymentDataObjectFactory $paymentDataObjectFactory
+     */
+    public function __construct(
+        CommandPoolInterface $commandPool,
+        PaymentDataObjectFactory $paymentDataObjectFactory
+    ) {
+        $this->commandPool = $commandPool;
+        $this->paymentDataObjectFactory = $paymentDataObjectFactory;
+    }
+
+    /**
+     * Process Api request
+     *
+     * @param Order $order
+     * @param string $command
+     * @return ResultInterface|null|bool|array <mixed>
+     */
+    public function process(Order $order, $command)
+    {
+        $result = [];
+        /** @var InfoInterface $payment*/
+        $payment = $order->getPayment();
+
+        try {
+            $paymentDataObject = $this->paymentDataObjectFactory->create($payment);
+            /** @var array <mixed> $result */
+            $result = $this->commandPool->get($command)->execute([
+                'payment' => $paymentDataObject
+            ]);
+            return $result;
+        } catch (Exception $e) {
+            return $result;
+        }
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/Api/Request.php

+<?php
+namespace Payoneer\OpenPaymentGateway\Model\Api;
+
+use Magento\Framework\DataObject;
+use Magento\Framework\Webapi\Rest\Request as WebRequest;
+use Payoneer\OpenPaymentGateway\Gateway\Config\Config;
+use Payoneer\OpenPaymentGateway\Http\PayoneerClient;
+
+/**
+ * Class Request - Manage Payoneer API requests
+ */
+class Request
+{
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * @var PayoneerClient
+     */
+    protected $payoneerHttpClient;
+
+    /**
+     * Request constructor.
+     * @param Config $config
+     * @param PayoneerClient $payoneerHttpClient
+     */
+    public function __construct(
+        Config $config,
+        PayoneerClient $payoneerHttpClient
+    ) {
+        $this->config = $config;
+        $this->payoneerHttpClient = $payoneerHttpClient;
+    }
+
+    /**
+     * @param int|string $method
+     * @param string $endPoint
+     * @param array <mixed> $credentials
+     * @param array <mixed>|string $data
+     * @return DataObject
+     */
+    public function send(
+        $method,
+        $endPoint,
+        $credentials,
+        $data
+    ): DataObject {
+        $options = [];
+        if ($method == WebRequest::HTTP_METHOD_GET) {
+            $options['query']   =   $data;
+        } else {
+            $options['json']  =   $data;
+        }
+        $options['headers'] = $this->config->prepareHeaders($credentials['merchantCode'], $credentials['apiKey']);
+
+        return $this->payoneerHttpClient->send($method, $credentials['hostName'], $endPoint, $options);
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/Api/Response.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Model\Api;
+
+/**
+ * Class Response - Validate API response
+ */
+class Response
+{
+    /**
+     * @var array<mixed>
+     */
+    protected $responseCodes = [
+        'success' => ['200','201','204'],
+        'invalid_token' => ['401', '403']
+    ];
+
+    /**
+     * @param string $key
+     * @return array<mixed>
+     */
+    public function getResponseCode(string $key): array
+    {
+        return $this->responseCodes[$key];
+    }
+
+    /**
+     * @param mixed $response
+     * @return bool|string
+     */
+    public function validateResponse($response)
+    {
+        return in_array($response->getStatus(), $this->getResponseCode('success'));
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/Config/Source/PaymentIconType.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Model\Config\Source;
+
+use Magento\Framework\Data\OptionSourceInterface;
+
+class PaymentIconType implements OptionSourceInterface
+{
+    const PAYMENT_ICON_STATIC   = 'static';
+    const PAYMENT_ICON_DYNAMIC  = 'dynamic';
+    const PAYMENT_ICON_BOTH     = 'both';
+
+    /**
+     * Payment icon types
+     *
+     * @return array <mixed>
+     */
+    public function toOptionArray(): array
+    {
+        return [
+            [
+                'value' => self::PAYMENT_ICON_STATIC,
+                'label' => __('Static')
+            ],
+            [
+                'value' => self::PAYMENT_ICON_DYNAMIC,
+                'label' => __('Dynamic')
+            ],
+            [
+                'value' => self::PAYMENT_ICON_BOTH,
+                'label' => __('Both')
+            ]
+        ];
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/Creditmemo/CreditmemoCreator.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Model\Creditmemo;
+
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Sales\Api\InvoiceRepositoryInterface;
+use Magento\Sales\Model\Order;
+use Magento\Sales\Model\Order\CreditmemoFactory;
+use Magento\Sales\Model\Service\CreditmemoService;
+
+class CreditmemoCreator
+{
+    /**
+     * @var CreditmemoFactory
+     */
+    protected $creditmemoFactory;
+
+    /**
+     * @var CreditmemoService
+     */
+    protected $creditmemoService;
+
+    /**
+     * @var InvoiceRepositoryInterface
+     */
+    protected $invoiceRepository;
+
+    /**
+     * CreditmemoCreator constructor
+     *
+     * @param CreditmemoFactory $creditmemoFactory
+     * @param CreditmemoService $creditmemoService
+     * @param InvoiceRepositoryInterface $invoiceRepository
+     * @return void
+     */
+    public function __construct(
+        CreditmemoFactory $creditmemoFactory,
+        CreditmemoService $creditmemoService,
+        InvoiceRepositoryInterface $invoiceRepository
+    ) {
+        $this->creditmemoFactory = $creditmemoFactory;
+        $this->creditmemoService = $creditmemoService;
+        $this->invoiceRepository = $invoiceRepository;
+    }
+
+    /**
+     * Create creditmemo for full order.
+     *
+     * @param Order $order
+     * @return bool
+     * @throws LocalizedException
+     */
+    public function create($order)
+    {
+        try {
+            $invoices = $order->getInvoiceCollection();
+            $invoiceId = 0;
+            foreach ($invoices as $invoice) {
+                $invoiceId = $invoice->getId();
+            }
+
+            $invoice = $this->invoiceRepository->get($invoiceId);
+            $creditmemo = $this->creditmemoFactory->createByOrder($order);
+            $creditmemo->setData('invoice', $invoice);
+
+            $this->creditmemoService->refund($creditmemo, true);
+            return true;
+        } catch (\Exception $e) {
+            throw new LocalizedException(
+                __(__('We couldn\'t create a credit memo for the %1 order. Try again later.') . $e->getMessage(), $order->getIncrementId())
+            );
+        }
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/ListUpdateTransactionService.php

+<?php
+namespace Payoneer\OpenPaymentGateway\Model;
+
+use Exception;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Payment\Gateway\Command\CommandPoolInterface;
+use Magento\Payment\Gateway\Command\ResultInterface;
+use Magento\Payment\Gateway\Data\PaymentDataObjectFactory;
+use Magento\Payment\Model\InfoInterface;
+use Magento\Quote\Model\Quote\Payment;
+
+/**
+ * Class ListUpdateTransactionService
+ *
+ * Process transactions api request for list update
+ */
+class ListUpdateTransactionService
+{
+    /**
+     * @var CommandPoolInterface
+     */
+    private $commandPool;
+
+    /**
+     * @var PaymentDataObjectFactory
+     */
+    private $paymentDataObjectFactory;
+
+    /**
+     * ListUpdateTransactionService constructor.
+     *
+     * @param CommandPoolInterface $commandPool
+     * @param PaymentDataObjectFactory $paymentDataObjectFactory
+     */
+    public function __construct(
+        CommandPoolInterface $commandPool,
+        PaymentDataObjectFactory $paymentDataObjectFactory
+    ) {
+        $this->commandPool = $commandPool;
+        $this->paymentDataObjectFactory = $paymentDataObjectFactory;
+    }
+
+    /**
+     * Process Api request
+     *
+     * @param Payment $payment
+     * @param string $command
+     * @return ResultInterface|null|bool|array <mixed>
+     * @throws LocalizedException
+     */
+    public function process(Payment $payment, $command)
+    {
+        try {
+            /** @var InfoInterface $payment*/
+            $paymentDataObject = $this->paymentDataObjectFactory->create($payment);
+
+            return $this->commandPool->get($command)->execute([
+                'payment' => $paymentDataObject,
+                'amount' => $payment->getQuote()->getGrandTotal(), /** @phpstan-ignore-line */
+                'totalItemsCount' => $payment->getQuote()->getItemsCount() /** @phpstan-ignore-line */
+            ]);
+        } catch (Exception $e) {
+            throw new LocalizedException(__($e->getMessage()));
+        }
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/Method/Logger.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Model\Method;
+
+use Magento\Payment\Gateway\ConfigInterface;
+use Psr\Log\LoggerInterface;
+use Magento\Framework\App\ProductMetadataInterface;
+use Magento\Framework\Module\ModuleListInterface;
+
+/**
+ * Class Logger for payment related information (request, response, etc.) which is used for debug.
+ *
+ * @api
+ * @since 100.0.2
+ */
+class Logger
+{
+    const MODULE_NAME = 'Payoneer_OpenPaymentGateway';
+    const DEBUG_KEYS_MASK = '****';
+
+    /**
+     * @var LoggerInterface
+     */
+    protected $logger;
+
+    /**
+     * @var ConfigInterface|null
+     */
+    private $config;
+
+    /**
+     * @var ProductMetadataInterface
+     */
+    protected $productMetadata;
+
+    /**
+     * @var ModuleListInterface
+     */
+    protected $moduleList;
+
+    /**
+     * @param ProductMetadataInterface $productMetadata
+     * @param ModuleListInterface $moduleList
+     * @param LoggerInterface $logger
+     * @param ConfigInterface|null $config
+     */
+    public function __construct(
+        ProductMetadataInterface $productMetadata,
+        ModuleListInterface $moduleList,
+        LoggerInterface $logger,
+        ConfigInterface $config = null
+    ) {
+        $this->productMetadata = $productMetadata;
+        $this->moduleList = $moduleList;
+        $this->logger = $logger;
+        $this->config = $config;
+    }
+
+    /**
+     * Logs payment related information used for debug
+     *
+     * @param array <mixed> $data
+     * @param array <mixed>|null $maskKeys
+     * @param bool|null $forceDebug
+     * @return void
+     */
+    public function debug(array $data, array $maskKeys = null, $forceDebug = null)
+    {
+        $data = array_merge($data, $this->getProductMetaData());
+        $maskKeys = $maskKeys !== null ? $maskKeys : $this->getDebugReplaceFields();
+        $debugOn = $forceDebug !== null ? $forceDebug : $this->isDebugOn();
+        if ($debugOn === true) {
+            $data = $this->filterDebugData(
+                $data,
+                $maskKeys
+            );
+            $this->logger->debug(var_export($data, true));
+        }
+    }
+
+    /**
+     * Returns configured keys to be replaced with mask
+     *
+     * @return array <mixed>
+     */
+    private function getDebugReplaceFields()
+    {
+        if ($this->config && $this->config->getValue('debugReplaceKeys')) {
+            return explode(',', $this->config->getValue('debugReplaceKeys'));
+        }
+        return [];
+    }
+
+    /**
+     * Whether debug is enabled in configuration
+     *
+     * @return bool
+     */
+    private function isDebugOn()
+    {
+        return $this->config && (bool)$this->config->getValue('debug');
+    }
+
+    /**
+     * Recursive filter data by private conventions
+     *
+     * @param array <mixed> $debugData
+     * @param array <mixed> $debugReplacePrivateDataKeys
+     * @return array <mixed>
+     */
+    protected function filterDebugData(array $debugData, array $debugReplacePrivateDataKeys)
+    {
+        $debugReplacePrivateDataKeys = array_map('strtolower', $debugReplacePrivateDataKeys);
+
+        foreach (array_keys($debugData) as $key) {
+            if (in_array(strtolower($key), $debugReplacePrivateDataKeys)) {
+                $debugData[$key] = self::DEBUG_KEYS_MASK;
+            } elseif (is_array($debugData[$key])) {
+                $debugData[$key] = $this->filterDebugData($debugData[$key], $debugReplacePrivateDataKeys);
+            }
+        }
+        return $debugData;
+    }
+
+    /**
+     * Get Magento application product metadata
+     * @return array <mixed>
+     */
+    public function getProductMetaData()
+    {
+        return [
+            'magentoVersion'    =>  $this->productMetadata->getVersion(),
+            'magentoEdition'    =>  $this->productMetadata->getEdition(),
+            'moduleVersion'     =>  $this->getModuleVersion()
+        ];
+    }
+
+    /**
+     * Find the installed module version
+     *
+     * @return mixed
+     */
+    public function getModuleVersion()
+    {
+        $module = $this->moduleList->getOne(self::MODULE_NAME);
+        return $module ? $module ['setup_version'] : null;
+    }
+}

app/code/Payoneer/OpenPaymentGateway/Model/NotificationEmailSender.php

+<?php
+
+namespace Payoneer\OpenPaymentGateway\Model;
+
+use Magento\Framework\Mail\Template\TransportBuilder;
+use Magento\Store\Model\StoreManagerInterface;
+use Magento\Framework\App\Area;
+use Magento\Framework\App\Config\ScopeConfigInterface;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Store\Model\ScopeInterface;
+
+class NotificationEmailSender
+{
+    const NOTIFICATION_EMAIL_TEMPLATE_ID = "notification_email_template";
+
+    /**
+     * @var TransportBuilder
+     */
+    private $transportBuilder;
+
+    /**
+     * @var StoreManagerInterface
+     */
+    private $storeManager;
+
+    /**
+     * @var ScopeConfigInterface
+     */
+    private $scopeConfig;
+
+    /**
+     * Initialize dependencies.
+     *
+     * @param TransportBuilder $transportBuilder
+     * @param StoreManagerInterface $storeManager
+     * @param ScopeConfigInterface $scopeConfig
+     */
+    public function __construct(
+        TransportBuilder $transportBuilder,
+        StoreManagerInterface $storeManager,
+        ScopeConfigInterface $scopeConfig
+    ) {
+        $this->transportBuilder = $transportBuilder;
+        $this->storeManager = $storeManager;
+        $this->scopeConfig = $scopeConfig;
+    }
+
+    /**
+     * Send notification email
+     *
+     * @param array <mixed> $notificationResponse
+     * @return void
+     */
+    public function send($notificationResponse)
+    {
+        $emailTemplateVars = $this->prepareEmailTemplateVars($notificationResponse);
+        $storeId = $this->storeManager->getStore()->getId();
+        $fromToAddressData = $this->getSenderDetails($storeId);
+        try {
+            $transport = $this->transportBuilder
+                ->setTemplateIdentifier(self::NOTIFICATION_EMAIL_TEMPLATE_ID)
+                ->setTemplateOptions(
+                    [
+                        'area' => Area::AREA_FRONTEND,
+                        'store' => $storeId
+                    ]
+                )
+                ->setTemplateVars($emailTemplateVars)
+                ->setFromByScope($fromToAddressData)
+                ->addTo($fromToAddressData['email'], $fromToAddressData['name'])
+                ->getTransport();
+
+            $transport->sendMessage();
+        } catch (\Exception $e) {
+            throw new LocalizedException(
+                __('Error sending email = %1', $e->getMessage())
+            );
+        }
+    }
+
+    /**
+     * Prepare the email template variables.
+     *
+     * @param array <mixed> $notificationResponse
+     * @return array <mixed>
+     */
+    private function prepareEmailTemplateVars($notificationResponse)
+    {
+        $emailTemplateVars = [];
+        $emailTemplateVars['resultCode'] = isset($notificationResponse['resultCode'])
+            ? $notificationResponse['resultCode'] : '';
+        $emailTemplateVars['longId'] = isset($notificationResponse['longId'])
+            ? $notificationResponse['longId'] : '';
+        $emailTemplateVars['transactionId'] = isset($notificationResponse['transactionId'])
+            ? $notificationResponse['transactionId'] : '';
+        $emailTemplateVars['interactionCode'] = isset($notificationResponse['interactionCode'])
+            ? $notificationResponse['interactionCode'] : '';
+        $emailTemplateVars['notificationId'] = isset($notificationResponse['notificationId'])
+            ? $notificationResponse['notificationId'] : '';
+        $emailTemplateVars['reasonCode'] = isset($notificationResponse['reasonCode'])
+            ? $notificationResponse['reasonCode'] : '';
+        $emailTemplateVars['statusCode'] = isset($notificationResponse['statusCode'])
+            ? $notificationResponse['statusCode'] : '';
+
+        return $emailTemplateVars;
+    }
+
+    /**
+     * Get the email sender details
+     *
+     * @param int $storeId
+     * @return array <mixed>
+     */
+    private function getSenderDetails($storeId)
+    {
+        $senderData = [];
+        $senderData['name'] = $this->scopeConfig->getValue(
+            'trans_email/ident_general/name',
+            ScopeInterface::SCOPE_STORE,
+            $storeId
+        );
+        $senderData['email'] = $this->scopeConfig->getValue(
+            'trans_email/ident_general/email',
+            ScopeInterface::SCOPE_STORE,
+            $storeId
+        );
+
+        return $senderData;
+    }
+}