Init repo

Helper/Data.php

+<?php
+
+namespace Meetanshi\Paymulti\Helper;
+
+use Magento\Framework\App\Helper\AbstractHelper;
+use Magento\Framework\App\Helper\Context;
+use Magento\Sales\Api\Data\OrderInterface;
+use Magento\Store\Model\ScopeInterface;
+use Magento\Store\Model\StoreManagerInterface;
+
+/**
+ * Class Data
+ * @package Meetanshi\Paymulti\Helper
+ */
+class Data extends AbstractHelper
+{
+    /**
+     *
+     */
+    const MEETANSHI_MODULE_ENABLE = 'paymulti/general/active';
+
+    /**
+     * @var StoreManagerInterface
+     */
+    protected $storeManager;
+
+    /**
+     * @var OrderInterface
+     */
+    protected $order;
+
+    /**
+     * @var
+     */
+    protected $extraPrice;
+
+    /**
+     * @var
+     */
+    protected $itemPrice;
+
+    /**
+     * Data constructor.
+     * @param Context $context
+     * @param StoreManagerInterface $storeManager
+     * @param OrderInterface $order
+     */
+    public function __construct(
+        Context $context,
+        StoreManagerInterface $storeManager,
+        OrderInterface $order
+    ) {
+        $this->storeManager = $storeManager;
+        $this->order = $order;
+        parent::__construct($context);
+    }
+
+    /**
+     * @return array
+     */
+    public static function getSupportedCurrency()
+    {
+        return ['AUD', 'CAD', 'CZK', 'DKK', 'EUR', 'HKD', 'HUF', 'ILS', 'JPY', 'MXN',
+            'NOK', 'NZD', 'PLN', 'GBP', 'SGD', 'SEK', 'CHF', 'USD', 'TWD', 'THB', 'INR'];
+    }
+
+    /**
+     * @return bool
+     */
+    public static function shouldConvert()
+    {
+        return !self::isActive();
+    }
+
+    /**
+     * @return mixed
+     */
+    public function isActive()
+    {
+        return $this->scopeConfig->getValue(self::MEETANSHI_MODULE_ENABLE, ScopeInterface::SCOPE_STORE);
+    }
+
+    /**
+     * @param $quote
+     * @return mixed
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function getConvertedGrandTotal($quote)
+    {
+        $toCurrency = $this->getCurrentCurrency();
+        $currentCurrency = $this->storeManager->getStore()->getCurrentCurrencyCode();
+        if ($toCurrency == $currentCurrency) {
+            return $quote->getGrandTotal();
+        } else {
+            return $this->getConvertedBaseAmount($quote->getBaseGrandTotal());
+        }
+    }
+
+    /**
+     * @return mixed
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function getCurrentCurrency()
+    {
+        return $this->storeManager->getStore()->getCurrentCurrency()->getCode();
+    }
+
+    /**
+     * @param $value
+     * @return mixed
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function getConvertedBaseAmount($value)
+    {
+        $baseCurrency = $this->storeManager->getStore()->getBaseCurrencyCode();
+        $currentCurrency = $this->getCurrentCurrency();
+        $amount = $this->convertCurrency($value, $baseCurrency, $currentCurrency);
+        return $amount;
+    }
+
+    /**
+     * @param $amountValue
+     * @param null $currencyCodeFrom
+     * @param null $currencyCodeTo
+     * @return mixed
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function convertCurrency($amountValue, $currencyCodeFrom = null, $currencyCodeTo = null)
+    {
+        return $this->storeManager->getStore()->getBaseCurrency()->convert($amountValue, $currencyCodeTo);
+    }
+
+    /**
+     * @return array
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function getCurrencyArray()
+    {
+        return [$this->storeManager->getStore()->getBaseCurrencyCode()];
+    }
+
+    /**
+     * @param $orderID
+     * @return mixed
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function getPaymentOrderCurrency($orderID)
+    {
+        $order = $this->order->load($orderID);
+        if ($order) {
+            $payment = $order->getPayment();
+            return $payment->getAdditionalInformation('payment_currency');
+        }
+        return $this->getCurrentCurrency();
+    }
+
+    /**
+     * @param $identifier
+     * @return mixed
+     */
+    public function getConfig($identifier)
+    {
+        return $this->scopeConfig->getValue(
+            $identifier,
+            ScopeInterface::SCOPE_STORE
+        );
+    }
+
+    /**
+     * @param $key
+     * @param $value
+     */
+    public function addExtraPrice($key, $value)
+    {
+        $this->extraPrice[$key] = $value;
+    }
+
+    /**
+     * @param $i
+     * @param $key
+     * @param $value
+     */
+    public function addItemPrice($i, $key, $value)
+    {
+        $this->itemPrice[$i][$key] = $value;
+    }
+
+    /**
+     * @param array $request
+     * @return array
+     */
+    public function convertRequest(array &$request)
+    {
+        $itemAmount = 0;
+        $extraprice = 0;
+        foreach ($this->itemPrice as $item) {
+            $itemAmount = $itemAmount + ((int)$item['qty'] * (float)$item['amount']);
+        }
+        foreach ($this->extraPrice as $key => $value) {
+            $extraprice = (float)$extraprice + (float)$value;
+        }
+        $baseprice = $extraprice + $itemAmount;
+
+        $request['AMT'] = number_format($baseprice,2);
+
+        $request['ITEMAMT'] = $itemAmount;
+        return $request;
+    }
+}

Model/Api/Nvp.php

+<?php
+
+namespace Meetanshi\Paymulti\Model\Api;
+
+use Magento\Payment\Model\Method\Logger;
+use Magento\Paypal\Model\Api\Nvp as PaypalNvp;
+
+/**
+ * Class Nvp
+ * @package Meetanshi\Paymulti\Model\Api
+ */
+class Nvp extends PaypalNvp
+{
+    /**
+     * @var \Meetanshi\Paymulti\Helper\Data
+     */
+    protected $helper;
+    /**
+     * @var \Magento\Framework\App\Request\Http
+     */
+    protected $request;
+
+    /**
+     * Nvp constructor.
+     * @param \Magento\Customer\Helper\Address $customerAddress
+     * @param \Psr\Log\LoggerInterface $logger
+     * @param Logger $customLogger
+     * @param \Magento\Framework\Locale\ResolverInterface $localeResolver
+     * @param \Magento\Directory\Model\RegionFactory $regionFactory
+     * @param \Magento\Directory\Model\CountryFactory $countryFactory
+     * @param \Magento\Paypal\Model\Api\ProcessableExceptionFactory $processableExceptionFactory
+     * @param \Magento\Framework\Exception\LocalizedExceptionFactory $frameworkExceptionFactory
+     * @param \Magento\Framework\HTTP\Adapter\CurlFactory $curlFactory
+     * @param \Meetanshi\Paymulti\Helper\Data $helper
+     * @param \Magento\Framework\App\Request\Http $request
+     * @param array $data
+     */
+    public function __construct(
+        \Magento\Customer\Helper\Address $customerAddress,
+        \Psr\Log\LoggerInterface $logger,
+        Logger $customLogger,
+        \Magento\Framework\Locale\ResolverInterface $localeResolver,
+        \Magento\Directory\Model\RegionFactory $regionFactory,
+        \Magento\Directory\Model\CountryFactory $countryFactory,
+        \Magento\Paypal\Model\Api\ProcessableExceptionFactory $processableExceptionFactory,
+        \Magento\Framework\Exception\LocalizedExceptionFactory $frameworkExceptionFactory,
+        \Magento\Framework\HTTP\Adapter\CurlFactory $curlFactory,
+        \Meetanshi\Paymulti\Helper\Data $helper,
+        \Magento\Framework\App\Request\Http $request,
+        array $data = []
+    )
+    {
+        $this->helper = $helper;
+        $this->request = $request;
+        parent::__construct($customerAddress, $logger, $customLogger, $localeResolver, $regionFactory, $countryFactory, $processableExceptionFactory, $frameworkExceptionFactory, $curlFactory, $data);
+    }
+
+    /**
+     * @throws \Magento\Framework\Exception\LocalizedException
+     */
+    public function callSetExpressCheckout()
+    {
+        $this->_prepareExpressCheckoutCallRequest($this->_setExpressCheckoutRequest);
+        $request = $this->_exportToRequest($this->_setExpressCheckoutRequest);
+        $this->_exportLineItems($request);
+
+        // import/suppress shipping address, if any
+        $options = $this->getShippingOptions();
+        if ($this->getAddress()) {
+            $request = $this->_importAddresses($request);
+            $request['ADDROVERRIDE'] = 0;
+        } elseif ($options && count($options) <= 10) {
+            // doesn't support more than 10 shipping options
+            $request['CALLBACK'] = $this->getShippingOptionsCallbackUrl();
+            $request['CALLBACKTIMEOUT'] = 6;
+            // max value
+            $request['MAXAMT'] = $request['AMT'] + 999.00;
+            // it is impossible to calculate max amount
+            $this->_exportShippingOptions($request);
+        }
+
+        $response = $this->call(self::SET_EXPRESS_CHECKOUT, $request);
+        $this->_importFromResponse($this->_setExpressCheckoutResponse, $response);
+    }
+
+    /**
+     * @param array $request
+     * @param int $i
+     * @return array|bool|true|void|null
+     */
+    protected function _exportLineItems(array &$request, $i = 0)
+    {
+        if (!$this->_cart) {
+            return;
+        }
+        $this->_cart->setTransferDiscountAsItem();
+        return $this->_exportPayPalLineItems($request, $i);
+    }
+
+    /**
+     * @param array $request
+     * @param int $i
+     * @return array|bool|void|null
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    protected function _exportPayPalLineItems(array &$request, $i = 0)
+    {
+        if (!$this->_cart) {
+            return;
+        }
+
+        if ($this->_lineItemTotalExportMap) {
+            foreach ($this->_cart->getAmounts() as $key => $total) {
+                if (isset($this->_lineItemTotalExportMap[$key])) {
+                    if ($this->helper->isActive()) {
+                        $total = $this->helper->getConvertedBaseAmount($total);
+                    }
+
+                    $privateKey = $this->_lineItemTotalExportMap[$key];
+                    $request[$privateKey] = $this->formatPrice($total);
+
+                    if ($key != 'subtotal') {
+                        $this->helper->addExtraPrice($key, $total);
+                    }
+                }
+            }
+        }
+
+        $items = $this->_cart->getAllItems();
+        if (empty($items) || !$this->getIsLineItemsEnabled()) {
+            return;
+        }
+
+        $result = null;
+        foreach ($items as $item) {
+            foreach ($this->_lineItemExportItemsFormat as $publicKey => $privateFormat) {
+                $result = true;
+                $value = $item->getDataUsingMethod($publicKey);
+                if ($publicKey == 'amount' && $this->helper->isActive()) {
+                    $value = $this->helper->getConvertedBaseAmount($value);
+                }
+
+                if ($publicKey == 'qty') {
+                    $this->helper->addItemPrice($i, 'qty', $value);
+                }
+                if ($publicKey == 'amount') {
+                    $this->helper->addItemPrice($i, 'amount', number_format($value, 2));
+                }
+
+                $request[sprintf($privateFormat, $i)] = $this->formatAmount($value, $publicKey);
+            }
+            $i++;
+        }
+        $result = $this->helper->convertRequest($request);
+        return $result;
+    }
+
+    /**
+     * @param $value
+     * @param $publicKey
+     * @return string
+     */
+    private function formatAmount($value, $publicKey)
+    {
+        if (!empty($this->_lineItemExportItemsFilters[$publicKey])) {
+            $callback = $this->_lineItemExportItemsFilters[$publicKey];
+            $value = method_exists($this, $callback) ? $this->{$callback}($value) : $callback($value);
+        }
+
+        if (is_float($value)) {
+            $value = $this->formatPrice($value);
+        }
+
+        return $value;
+    }
+
+    /**
+     * @param array $request
+     * @param int $i
+     * @return bool
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    protected function _exportShippingOptions(array &$request, $i = 0)
+    {
+        $options = $this->getShippingOptions();
+        if (empty($options)) {
+            return false;
+        }
+        foreach ($options as $option) {
+            foreach ($this->_shippingOptionsExportItemsFormat as $publicKey => $privateFormat) {
+                $value = $option->getDataUsingMethod($publicKey);
+                if (is_float($value)) {
+                    if ($this->helper->isActive()) {
+                        $value = $this->helper->getConvertedBaseAmount($value);
+                    }
+                    $value = $this->formatPrice($value);
+                }
+                if (is_bool($value)) {
+                    $value = $this->_filterBool($value);
+                }
+                $request[sprintf($privateFormat, $i)] = $value;
+            }
+            $i++;
+        }
+
+        return true;
+    }
+
+    /**
+     * @param string $methodName
+     * @param array $request
+     * @return array|false|string|string[]
+     * @throws \Magento\Framework\Exception\LocalizedException
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     * @throws \Magento\Paypal\Model\Api\ProcessableException
+     */
+    public function call($methodName, array $request)
+    {
+        $request = $this->_addMethodToRequest($methodName, $request);
+        $eachCallRequest = $this->_prepareEachCallRequest($methodName);
+        if ($this->getUseCertAuthentication()) {
+            $key = array_search('SIGNATURE', $eachCallRequest);
+            if ($key) {
+                unset($eachCallRequest[$key]);
+            }
+        }
+        $request = $this->_exportToRequest($eachCallRequest, $request);
+        $debugData = ['url' => $this->getApiEndpoint(), $methodName => $request];
+
+        if (isset($request['METHOD']) && ($request['METHOD'] == self::DO_CAPTURE ||
+                $request['METHOD'] == self::REFUND_TRANSACTION)) {
+            $orderId = $this->request->getParam('order_id');
+            if ($orderId) {
+                $paymentCurrency = $this->helper->getPaymentOrderCurrency($orderId);
+                $request['AMT'] = number_format($this->helper->convertCurrency($request['AMT'], null, $paymentCurrency), 2);
+                $request['CURRENCYCODE'] = $paymentCurrency;
+            }
+        }
+
+        try {
+            $http = $this->_curlFactory->create();
+            $config = ['timeout' => 60, 'verifypeer' => $this->_config->getValue('verifyPeer')];
+            if ($this->getUseProxy()) {
+                $config['proxy'] = $this->getProxyHost() . ':' . $this->getProxyPort();
+            }
+            if ($this->getUseCertAuthentication()) {
+                $config['ssl_cert'] = $this->getApiCertificate();
+            }
+            $http->setConfig($config);
+            $http->write(
+                \Zend_Http_Client::POST,
+                $this->getApiEndpoint(),
+                '1.1',
+                $this->_headers,
+                $this->_buildQuery($request)
+            );
+            $response = $http->read();
+        } catch (\Exception $e) {
+            $debugData['http_error'] = ['error' => $e->getMessage(), 'code' => $e->getCode()];
+            $this->_debug($debugData);
+            throw $e;
+        }
+        $response = preg_split('/^\r?$/m', $response, 2);
+        $response = trim($response[1]);
+        $response = $this->_deformatNVP($response);
+
+        $debugData['response'] = $response;
+        $this->_debug($debugData);
+
+        $response = $this->_postProcessResponse($response);
+
+        // handle transport error
+        if ($http->getErrno()) {
+            $this->_logger->critical(
+                new \Exception(
+                    sprintf('PayPal NVP CURL connection error #%s: %s', $http->getErrno(), $http->getError())
+                )
+            );
+            $http->close();
+
+            throw new \Magento\Framework\Exception\LocalizedException(
+                __('Payment Gateway is unreachable at the moment. Please use another payment option.')
+            );
+        }
+
+        // cUrl resource must be closed after checking it for errors
+        $http->close();
+
+        if (!$this->_validateResponse($methodName, $response)) {
+            $this->_logger->critical(new \Exception(__('PayPal response hasn\'t required fields.')));
+            throw new \Magento\Framework\Exception\LocalizedException(
+                __('Something went wrong while processing your order.')
+            );
+        }
+
+        $this->_callErrors = [];
+        if ($this->_isCallSuccessful($response)) {
+            if ($this->_rawResponseNeeded) {
+                $this->setRawSuccessResponseData($response);
+            }
+            return $response;
+        }
+        $this->_handleCallErrors($response);
+        return $response;
+    }
+
+    /**
+     * @throws \Magento\Framework\Exception\LocalizedException
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     * @throws \Magento\Paypal\Model\Api\ProcessableException
+     */
+    public function callDoExpressCheckoutPayment()
+    {
+        $this->_prepareExpressCheckoutCallRequest($this->_doExpressCheckoutPaymentRequest);
+        $request = $this->_exportToRequest($this->_doExpressCheckoutPaymentRequest);
+        $this->_exportLineItems($request);
+
+        if ($this->getAddress()) {
+            $request = $this->_importAddresses($request);
+            $request['ADDROVERRIDE'] = 0;
+        }
+
+        $response = $this->call(self::DO_EXPRESS_CHECKOUT_PAYMENT, $request);
+        $this->_importFromResponse($this->_paymentInformationResponse, $response);
+        $this->_importFromResponse($this->_doExpressCheckoutPaymentResponse, $response);
+        $this->_importFromResponse($this->_createBillingAgreementResponse, $response);
+    }
+}

Model/Express.php

+<?php
+
+namespace Meetanshi\Paymulti\Model;
+
+use Magento\Paypal\Model\Express\Checkout as ExpressCheckout;
+use Meetanshi\Paymulti\Helper\Data;
+use Magento\Paypal\Model\Express as PaypalExpress;
+
+/**
+ * Class Express
+ * @package Meetanshi\Paymulti\Model
+ */
+class Express extends PaypalExpress
+{
+    /**
+     * @var Data
+     */
+    protected $helper;
+
+    /**
+     * Express constructor.
+     * @param \Magento\Framework\Model\Context $context
+     * @param \Magento\Framework\Registry $registry
+     * @param \Magento\Framework\Api\ExtensionAttributesFactory $extensionFactory
+     * @param \Magento\Framework\Api\AttributeValueFactory $customAttributeFactory
+     * @param \Magento\Payment\Helper\Data $paymentData
+     * @param \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig
+     * @param \Magento\Payment\Model\Method\Logger $logger
+     * @param \Magento\Paypal\Model\ProFactory $proFactory
+     * @param \Magento\Store\Model\StoreManagerInterface $storeManager
+     * @param \Magento\Framework\UrlInterface $urlBuilder
+     * @param \Magento\Paypal\Model\CartFactory $cartFactory
+     * @param \Magento\Checkout\Model\Session $checkoutSession
+     * @param \Magento\Framework\Exception\LocalizedExceptionFactory $exception
+     * @param \Magento\Sales\Api\TransactionRepositoryInterface $transactionRepository
+     * @param \Magento\Sales\Model\Order\Payment\Transaction\BuilderInterface $transactionBuilder
+     * @param Data $helper
+     * @param array $data
+     */
+    public function __construct(
+        \Magento\Framework\Model\Context $context,
+        \Magento\Framework\Registry $registry,
+        \Magento\Framework\Api\ExtensionAttributesFactory $extensionFactory,
+        \Magento\Framework\Api\AttributeValueFactory $customAttributeFactory,
+        \Magento\Payment\Helper\Data $paymentData,
+        \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig,
+        \Magento\Payment\Model\Method\Logger $logger,
+        \Magento\Paypal\Model\ProFactory $proFactory,
+        \Magento\Store\Model\StoreManagerInterface $storeManager,
+        \Magento\Framework\UrlInterface $urlBuilder,
+        \Magento\Paypal\Model\CartFactory $cartFactory,
+        \Magento\Checkout\Model\Session $checkoutSession,
+        \Magento\Framework\Exception\LocalizedExceptionFactory $exception,
+        \Magento\Sales\Api\TransactionRepositoryInterface $transactionRepository,
+        \Magento\Sales\Model\Order\Payment\Transaction\BuilderInterface $transactionBuilder,
+        Data $helper,
+        array $data = []
+    )
+    {
+        $this->helper = $helper;
+        parent::__construct($context, $registry, $extensionFactory, $customAttributeFactory, $paymentData, $scopeConfig, $logger, $proFactory, $storeManager, $urlBuilder, $cartFactory, $checkoutSession, $exception, $transactionRepository, $transactionBuilder, null, null, $data);
+    }
+
+    /**
+     * @param \Magento\Sales\Model\Order\Payment $payment
+     * @param float $amount
+     * @return $this|PaypalExpress
+     * @throws \Magento\Framework\Exception\LocalizedException
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    protected function _placeOrder(\Magento\Sales\Model\Order\Payment $payment, $amount)
+    {
+        $order = $payment->getOrder();
+
+        // prepare api call
+        $token = $payment->getAdditionalInformation(ExpressCheckout::PAYMENT_INFO_TRANSPORT_TOKEN);
+
+        $cart = $this->_cartFactory->create(['salesModel' => $order]);
+
+        if ($this->helper->isActive()) {
+            $amount = number_format($this->helper->getConvertedGrandTotal($order), 2);
+            $currencyCode = $this->helper->getCurrentCurrency();
+        } else {
+            $amount = $amount;
+            $currencyCode = $order->getBaseCurrencyCode();
+        }
+
+        $payment->setAdditionalInformation('payment_currency', $currencyCode);
+        $api = $this->getApi()->setToken(
+            $token
+        )->setPayerId(
+            $payment->getAdditionalInformation(ExpressCheckout::PAYMENT_INFO_TRANSPORT_PAYER_ID)
+        )->setAmount(
+            $amount
+        )->setPaymentAction(
+            $this->_pro->getConfig()->getValue('paymentAction')
+        )->setNotifyUrl(
+            $this->_urlBuilder->getUrl('paypal/ipn/')
+        )->setInvNum(
+            $order->getIncrementId()
+        )->setCurrencyCode(
+            $currencyCode
+        )->setPaypalCart(
+            $cart
+        )->setIsLineItemsEnabled(
+            $this->_pro->getConfig()->getValue('lineItemsEnabled')
+        );
+        if ($order->getIsVirtual()) {
+            $api->setAddress($order->getBillingAddress())->setSuppressShipping(true);
+        } else {
+            $api->setAddress($order->getShippingAddress());
+            $api->setBillingAddress($order->getBillingAddress());
+        }
+
+        // call api and get details from it
+        $api->callDoExpressCheckoutPayment();
+
+        $this->_importToPayment($api, $payment);
+        return $this;
+    }
+}

Model/Express/Checkout.php

+<?php
+
+namespace Meetanshi\Paymulti\Model\Express;
+
+use Magento\Customer\Model\AccountManagement;
+use Magento\Paypal\Model\Cart as PaypalCart;
+use Magento\Paypal\Model\Config as PaypalConfig;
+use Magento\Quote\Model\Quote\Address;
+use Magento\Sales\Model\Order\Email\Sender\OrderSender;
+use Magento\Paypal\Model\Express\Checkout as ExpressCheckout;
+
+/**
+ * Class Checkout
+ * @package Meetanshi\Paymulti\Model\Express
+ */
+class Checkout extends ExpressCheckout
+{
+    /**
+     * @var \Meetanshi\Paymulti\Helper\Data
+     */
+    protected $helper;
+
+    /**
+     * Checkout constructor.
+     * @param \Psr\Log\LoggerInterface $logger
+     * @param \Magento\Customer\Model\Url $customerUrl
+     * @param \Magento\Tax\Helper\Data $taxData
+     * @param \Magento\Checkout\Helper\Data $checkoutData
+     * @param \Magento\Customer\Model\Session $customerSession
+     * @param \Magento\Framework\App\Cache\Type\Config $configCacheType
+     * @param \Magento\Framework\Locale\ResolverInterface $localeResolver
+     * @param \Magento\Paypal\Model\Info $paypalInfo
+     * @param \Magento\Store\Model\StoreManagerInterface $storeManager
+     * @param \Magento\Framework\UrlInterface $coreUrl
+     * @param \Magento\Paypal\Model\CartFactory $cartFactory
+     * @param \Magento\Checkout\Model\Type\OnepageFactory $onepageFactory
+     * @param \Magento\Quote\Api\CartManagementInterface $quoteManagement
+     * @param \Magento\Paypal\Model\Billing\AgreementFactory $agreementFactory
+     * @param \Magento\Paypal\Model\Api\Type\Factory $apiTypeFactory
+     * @param \Magento\Framework\DataObject\Copy $objectCopyService
+     * @param \Magento\Checkout\Model\Session $checkoutSession
+     * @param \Magento\Framework\Encryption\EncryptorInterface $encryptor
+     * @param \Magento\Framework\Message\ManagerInterface $messageManager
+     * @param \Magento\Customer\Api\CustomerRepositoryInterface $customerRepository
+     * @param AccountManagement $accountManagement
+     * @param OrderSender $orderSender
+     * @param \Magento\Quote\Api\CartRepositoryInterface $quoteRepository
+     * @param \Magento\Quote\Model\Quote\TotalsCollector $totalsCollector
+     * @param \Meetanshi\Paymulti\Helper\Data $helper
+     * @param array $params
+     * @throws \Exception
+     */
+    public function __construct(
+        \Psr\Log\LoggerInterface $logger,
+        \Magento\Customer\Model\Url $customerUrl,
+        \Magento\Tax\Helper\Data $taxData,
+        \Magento\Checkout\Helper\Data $checkoutData,
+        \Magento\Customer\Model\Session $customerSession,
+        \Magento\Framework\App\Cache\Type\Config $configCacheType,
+        \Magento\Framework\Locale\ResolverInterface $localeResolver,
+        \Magento\Paypal\Model\Info $paypalInfo,
+        \Magento\Store\Model\StoreManagerInterface $storeManager,
+        \Magento\Framework\UrlInterface $coreUrl,
+        \Magento\Paypal\Model\CartFactory $cartFactory,
+        \Magento\Checkout\Model\Type\OnepageFactory $onepageFactory,
+        \Magento\Quote\Api\CartManagementInterface $quoteManagement,
+        \Magento\Paypal\Model\Billing\AgreementFactory $agreementFactory,
+        \Magento\Paypal\Model\Api\Type\Factory $apiTypeFactory,
+        \Magento\Framework\DataObject\Copy $objectCopyService,
+        \Magento\Checkout\Model\Session $checkoutSession,
+        \Magento\Framework\Encryption\EncryptorInterface $encryptor,
+        \Magento\Framework\Message\ManagerInterface $messageManager,
+        \Magento\Customer\Api\CustomerRepositoryInterface $customerRepository,
+        AccountManagement $accountManagement,
+        OrderSender $orderSender,
+        \Magento\Quote\Api\CartRepositoryInterface $quoteRepository,
+        \Magento\Quote\Model\Quote\TotalsCollector $totalsCollector,
+        \Meetanshi\Paymulti\Helper\Data $helper,
+        $params = []
+    )
+    {
+
+        $this->helper = $helper;
+        parent::__construct($logger, $customerUrl, $taxData, $checkoutData, $customerSession, $configCacheType, $localeResolver, $paypalInfo, $storeManager, $coreUrl, $cartFactory, $onepageFactory, $quoteManagement, $agreementFactory, $apiTypeFactory, $objectCopyService, $checkoutSession, $encryptor, $messageManager, $customerRepository, $accountManagement, $orderSender, $quoteRepository, $totalsCollector, $params);
+    }
+
+    /**
+     * @param string $returnUrl
+     * @param string $cancelUrl
+     * @param null $button
+     * @return string
+     * @throws \Magento\Framework\Exception\LocalizedException
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function start($returnUrl, $cancelUrl, $button = null)
+    {
+        $this->_quote->collectTotals();
+
+        if (!$this->_quote->getGrandTotal()) {
+            throw new \Magento\Framework\Exception\LocalizedException(
+                __(
+                    'PayPal can\'t process orders with a zero balance due. '
+                    . 'To finish your purchase, please go through the standard checkout process.'
+                )
+            );
+        }
+
+        $this->_quote->reserveOrderId();
+        $this->quoteRepository->save($this->_quote);
+        // prepare API
+        $solutionType = $this->_config->getMerchantCountry() == 'DE'
+            ? \Magento\Paypal\Model\Config::EC_SOLUTION_TYPE_MARK
+            : $this->_config->getValue('solutionType');
+
+        if ($this->helper->isActive()) {
+            $totalAmount = $this->helper->getConvertedGrandTotal($this->_quote);
+            $currencyCode = $this->helper->getCurrentCurrency();
+        } else {
+            $totalAmount = round($this->_quote->getBaseGrandTotal(), 2);
+            $currencyCode = $this->_quote->getBaseCurrencyCode();
+        }
+
+        $this->_getApi()->setAmount($totalAmount)
+            ->setCurrencyCode($currencyCode)
+            ->setInvNum($this->_quote->getReservedOrderId())
+            ->setReturnUrl($returnUrl)
+            ->setCancelUrl($cancelUrl)
+            ->setSolutionType($solutionType)
+            ->setPaymentAction($this->_config->getValue('paymentAction'));
+        if ($this->_giropayUrls) {
+            list($successUrl, $cancelUrl, $pendingUrl) = $this->_giropayUrls;
+            $this->_getApi()->addData(
+                [
+                    'giropay_cancel_url' => $cancelUrl,
+                    'giropay_success_url' => $successUrl,
+                    'giropay_bank_txn_pending_url' => $pendingUrl,
+                ]
+            );
+        }
+
+        if ($this->_isBml) {
+            $this->_getApi()->setFundingSource('BML');
+        }
+
+        $this->_setBillingAgreementRequest();
+
+        if ($this->_config->getValue('requireBillingAddress') == PaypalConfig::REQUIRE_BILLING_ADDRESS_ALL) {
+            $this->_getApi()->setRequireBillingAddress(1);
+        }
+
+        // suppress or export shipping address
+        $address = null;
+        if ($this->_quote->getIsVirtual()) {
+            if ($this->_config->getValue('requireBillingAddress')
+                == PaypalConfig::REQUIRE_BILLING_ADDRESS_VIRTUAL
+            ) {
+                $this->_getApi()->setRequireBillingAddress(1);
+            }
+            $this->_getApi()->setSuppressShipping(true);
+        } else {
+            $this->_getApi()->setBillingAddress($this->_quote->getBillingAddress());
+
+            $address = $this->_quote->getShippingAddress();
+            $isOverridden = 0;
+            if (true === $address->validate()) {
+                $isOverridden = 1;
+                $this->_getApi()->setAddress($address);
+            }
+            $this->_quote->getPayment()->setAdditionalInformation(
+                self::PAYMENT_INFO_TRANSPORT_SHIPPING_OVERRIDDEN,
+                $isOverridden
+            );
+            $this->_quote->getPayment()->save();
+        }
+
+        /** @var $cart \Magento\Payment\Model\Cart */
+        $cart = $this->_cartFactory->create(['salesModel' => $this->_quote]);
+
+        $this->_getApi()->setPaypalCart($cart);
+
+        if (!$this->_taxData->getConfig()->priceIncludesTax()) {
+            $this->setShippingOptions($cart, $address);
+        }
+
+        $this->_config->exportExpressCheckoutStyleSettings($this->_getApi());
+
+        /* Temporary solution. @TODO: do not pass quote into Nvp model */
+        $this->_getApi()->setQuote($this->_quote);
+        $this->_getApi()->callSetExpressCheckout();
+
+        $token = $this->_getApi()->getToken();
+
+        $this->_setRedirectUrl($button, $token);
+
+        $payment = $this->_quote->getPayment();
+        $payment->unsAdditionalInformation(self::PAYMENT_INFO_TRANSPORT_BILLING_AGREEMENT);
+        // Set flag that we came from Express Checkout button
+        if (!empty($button)) {
+            $payment->setAdditionalInformation(self::PAYMENT_INFO_BUTTON, 1);
+        } elseif ($payment->hasAdditionalInformation(self::PAYMENT_INFO_BUTTON)) {
+            $payment->unsAdditionalInformation(self::PAYMENT_INFO_BUTTON);
+        }
+        $payment->save();
+
+        return $token;
+    }
+
+    /**
+     * @param PaypalCart $cart
+     * @param Address|null $address
+     */
+    private function setShippingOptions(PaypalCart $cart, Address $address = null)
+    {
+        // for included tax always disable line items (related to paypal amount rounding problem)
+        $this->_getApi()->setIsLineItemsEnabled($this->_config->getValue(PaypalConfig::TRANSFER_CART_LINE_ITEMS));
+
+        // add shipping options if needed and line items are available
+        $cartItems = $cart->getAllItems();
+        if ($this->_config->getValue(PaypalConfig::TRANSFER_CART_LINE_ITEMS)
+            && $this->_config->getValue(PaypalConfig::TRANSFER_SHIPPING_OPTIONS)
+            && !empty($cartItems)
+        ) {
+            if (!$this->_quote->getIsVirtual()) {
+                $options = $this->_prepareShippingOptions($address, true);
+                if ($options) {
+                    $this->_getApi()->setShippingOptionsCallbackUrl(
+                        $this->_coreUrl->getUrl(
+                            '*/*/shippingOptionsCallback',
+                            ['quote_id' => $this->_quote->getId()]
+                        )
+                    )->setShippingOptions($options);
+                }
+            }
+        }
+    }
+}

Model/Paypal/Config.php

+<?php
+
+namespace Meetanshi\Paymulti\Model\Paypal;
+
+use Magento\Paypal\Model\Config as PayPalConfig;
+
+/**
+ * Class Config
+ * @package Meetanshi\Paymulti\Model\Paypal
+ */
+class Config extends PayPalConfig
+{
+    /**
+     * @var \Meetanshi\Paymulti\Helper\Data
+     */
+    protected $helper;
+    /**
+     * @var array
+     */
+    protected $_supportedCurrencyCodes = [
+        'AUD',
+        'CAD',
+        'CZK',
+        'DKK',
+        'EUR',
+        'HKD',
+        'HUF',
+        'ILS',
+        'JPY',
+        'MXN',
+        'NOK',
+        'NZD',
+        'PLN',
+        'GBP',
+        'RUB',
+        'SGD',
+        'SEK',
+        'CHF',
+        'TWD',
+        'THB',
+        'USD',
+        'INR',
+    ];
+
+    /**
+     * Config constructor.
+     * @param \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig
+     * @param \Magento\Directory\Helper\Data $directoryHelper
+     * @param \Magento\Store\Model\StoreManagerInterface $storeManager
+     * @param \Magento\Payment\Model\Source\CctypeFactory $cctypeFactory
+     * @param \Magento\Paypal\Model\CertFactory $certFactory
+     * @param \Meetanshi\Paymulti\Helper\Data $helper
+     * @param array $params
+     */
+    public function __construct(
+        \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig,
+        \Magento\Directory\Helper\Data $directoryHelper,
+        \Magento\Store\Model\StoreManagerInterface $storeManager,
+        \Magento\Payment\Model\Source\CctypeFactory $cctypeFactory,
+        \Magento\Paypal\Model\CertFactory $certFactory,
+        \Meetanshi\Paymulti\Helper\Data $helper,
+        $params = []
+    ) {
+        parent::__construct($scopeConfig, $directoryHelper, $storeManager, $cctypeFactory, $certFactory, $params);
+        $this->helper = $helper;
+    }
+
+    /**
+     * @param string $code
+     * @return bool
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function isCurrencyCodeSupported($code)
+    {
+        if ($this->helper->isActive()) {
+            $this->_supportedCurrencyCodes =
+                array_merge($this->_supportedCurrencyCodes, $this->helper->getCurrencyArray());
+        }
+
+        if (in_array($code, $this->_supportedCurrencyCodes)) {
+            return true;
+        }
+        if ($this->getMerchantCountry() == 'BR' && $code == 'BRL') {
+            return true;
+        }
+        if ($this->getMerchantCountry() == 'MY' && $code == 'MYR') {
+            return true;
+        }
+        if ($this->getMerchantCountry() == 'TR' && $code == 'TRY') {
+            return true;
+        }
+        return false;
+    }
+}

Model/Source/Currency.php

+<?php
+
+namespace Meetanshi\Paymulti\Model\Source;
+
+/**
+ * Class Currency
+ * @package Meetanshi\Paymulti\Model\Source
+ */
+class Currency extends \Magento\Config\Model\Config\Source\Locale\Currency
+{
+    /**
+     * @var \Magento\Framework\Locale\ListsInterface
+     */
+    protected $_localeLists;
+    /**
+     * @var \Magento\Store\Model\StoreManagerInterface
+     */
+    protected $_currencySymbol;
+    /**
+     * @var \Meetanshi\Paymulti\Helper\Data
+     */
+    protected $_helper;
+
+    /**
+     * Currency constructor.
+     * @param \Magento\Framework\Locale\ListsInterface $localeLists
+     * @param \Magento\Store\Model\StoreManagerInterface $currencySymbol
+     * @param \Meetanshi\Paymulti\Helper\Data $helper
+     */
+    public function __construct(
+        \Magento\Framework\Locale\ListsInterface $localeLists,
+        \Magento\Store\Model\StoreManagerInterface $currencySymbol,
+        \Meetanshi\Paymulti\Helper\Data $helper
+    ) {
+        $this->_localeLists = $localeLists;
+        $this->_currencySymbol = $currencySymbol;
+        $this->_helper = $helper;
+        parent::__construct($localeLists);
+    }
+
+    /**
+     * @return array
+     * @throws \Magento\Framework\Exception\NoSuchEntityException
+     */
+    public function toOptionArray()
+    {
+        $_supportedCurrencyCodes = $this->_helper->getSupportedCurrency();
+        $_availableCurrencyCodes = $this->_currencySymbol->getStore()->getAvailableCurrencyCodes(true);
+        ;
+        if (!$this->_options) {
+            $this->_options = $this->_localeLists->getOptionCurrencies();
+        }
+        $options = [];
+        foreach ($this->_options as $option) {
+            if (in_array($option['value'], $_supportedCurrencyCodes) && in_array($option['value'], $_availableCurrencyCodes)) {
+                $options[] = $option;
+            }
+        }
+        return $options;
+    }
+}

composer.json

+{
+  "name": "meetanshi/magento2-paypal-multi-currency",
+  "description": "Magento 2 paypal multi currency",
+  "require": {
+    "php": "~5.5.0|~5.6.0|~7.0.0|7.0.2|7.0.4|~7.0.6|~7.1.0|~7.2.0|~7.3.0"
+  },
+  "type": "magento2-module",
+  "version": "1.0.4",
+  "license": [
+    "OSL-3.0"
+  ],
+  "autoload": {
+    "files": [
+      "registration.php"
+    ],
+    "psr-4": {
+      "Meetanshi\\Paymulti\\": ""
+    }
+  },
+  "support": {
+    "email": "support@meetanshi.com"
+  },
+  "authors": [
+    {
+      "name": "Jignesh Parmar",
+      "email": "support@meetanshi.com",
+      "homepage": "https://meetanshi.com"
+    }
+  ]
+}

etc/acl.xml

+<?xml version="1.0"?>
+<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Acl/etc/acl.xsd">
+    <acl>
+        <resources>
+            <resource id="Magento_Backend::admin">
+                <resource id="Magento_Backend::stores">
+                    <resource id="Magento_Backend::stores_settings">
+                        <resource id="Magento_Config::config">
+                            <resource id="Meetanshi_Paymulti::config_paymulti" title="Paypal Multi Currency" />
+                        </resource>
+                    </resource>
+                </resource>
+            </resource>
+        </resources>
+    </acl>
+</config>

etc/adminhtml/routes.xml

+<?xml version="1.0"?>
+<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:App/etc/routes.xsd">
+    <router id="admin">
+        <route id="paymulti" frontName="paymulti">
+            <module name="Meetanshi_Paymulti" />
+        </route>
+    </router>
+</config>

etc/adminhtml/system.xml

+<?xml version="1.0"?>
+<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Config:etc/system_file.xsd">
+    <system>
+        <tab id="meetanshi" translate="label" class="meetanshi" sortOrder="99998">
+            <label></label>
+        </tab>
+        <section id="paymulti" translate="label" type="text" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1">
+            <label>PayPal Multi Currency</label>
+            <tab>meetanshi</tab>
+            <resource>Meetanshi_Paymulti::config_paymulti</resource>
+            <group id="general" translate="label" type="text" sortOrder="100" showInDefault="1" showInWebsite="1" showInStore="1">
+                <label>Configuration</label>
+                <field id="active" translate="label" type="select" sortOrder="1" showInDefault="1" showInWebsite="1" showInStore="1">
+                    <label>PayPal Multi Currency</label>
+                    <source_model>Magento\Config\Model\Config\Source\Enabledisable</source_model>
+                </field>
+            </group>
+        </section>
+    </system>
+</config>

etc/config.xml

+<?xml version="1.0"?>
+<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Store:etc/config.xsd">
+ <default>
+  	<paymulti>
+   		<general>
+ 			<active>1</active>
+ 		</general>
+  	</paymulti>
+   </default>
+</config>

etc/di.xml

+<?xml version="1.0"?>
+<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../lib/internal/Magento/Framework/ObjectManager/etc/config.xsd">
+	<preference for="Magento\Paypal\Model\Express\Checkout" type="Meetanshi\Paymulti\Model\Express\Checkout"/>
+	<preference for="Magento\Paypal\Model\Api\Nvp" type="Meetanshi\Paymulti\Model\Api\Nvp"/>
+	<preference for="Magento\Paypal\Model\Express" type="Meetanshi\Paymulti\Model\Express"/>
+	<preference for="Magento\Paypal\Model\Config" type="Meetanshi\Paymulti\Model\Paypal\Config" />
+</config>

etc/module.xml

+<?xml version="1.0"?>
+<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Module/etc/module.xsd">
+    <module name="Meetanshi_Paymulti" setup_version="1.0.4" schema_version="1.0.4">
+    </module>
+</config>

registration.php

+<?php
+\Magento\Framework\Component\ComponentRegistrar::register(
+    \Magento\Framework\Component\ComponentRegistrar::MODULE,
+    'Meetanshi_Paymulti',
+    __DIR__
+);

view/adminhtml/layout/adminhtml_system_config_edit.xml

+<?xml version="1.0"?>
+<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
+    <head>
+        <css src="Meetanshi_Paymulti::css/meetanshi.css"/>
+    </head>
+</page>

view/adminhtml/web/css/meetanshi.css

+.meetanshi .title:before {
+    background-image: url(https://meetanshi.com/media/logo.png);
+    background-size: 150px 19px;
+    display: inline-block;
+    width: 150px;
+    height: 19px;
+    content: "";
+    background-repeat: no-repeat;
+}