Merge branch 'trunk' into PCP-190-override-language-used-to-display-PayPal-buttons

# Conflicts:
#	modules/ppcp-button/services.php
#	modules/ppcp-button/src/Assets/SmartButton.php
#	modules/ppcp-wc-gateway/services.php

modules/ppcp-button/src/Assets/ButtonInterface.php

@@ -0,0 +1,47 @@
+<?php
+/**
+ * The interface for the button asset renderer.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Assets
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Assets;
+
+/**
+ * Interface ButtonInterface
+ */
+interface ButtonInterface {
+
+	/**
+	 * Initializes the button.
+	 */
+	public function initialize(): void;
+
+	/**
+	 * Indicates if the button is enabled.
+	 *
+	 * @return bool
+	 */
+	public function is_enabled(): bool;
+
+	/**
+	 * Renders the necessary HTML.
+	 *
+	 * @return bool
+	 */
+	public function render(): bool;
+
+	/**
+	 * Enqueues scripts/styles.
+	 */
+	public function enqueue(): void;
+
+	/**
+	 * The configuration for the smart buttons.
+	 *
+	 * @return array
+	 */
+	public function script_data(): array;
+}

modules/ppcp-button/src/Assets/DisabledSmartButton.php

@@ -24,12 +24,16 @@ class DisabledSmartButton implements SmartButtonInterface {
 	}
 
 	/**
-	 * Enqueues necessary scripts.
-	 *
-	 * @return bool
+	 * Whether the scripts should be loaded.
 	 */
-	public function enqueue(): bool {
-		return true;
+	public function should_load_ppcp_script(): bool {
+		return false;
+	}
+
+	/**
+	 * Enqueues necessary scripts.
+	 */
+	public function enqueue(): void {
 	}
 
 	/**
@@ -41,4 +45,13 @@ class DisabledSmartButton implements SmartButtonInterface {
 
 		return false;
 	}
+
+	/**
+	 * The configuration for the smart buttons.
+	 *
+	 * @return array
+	 */
+	public function script_data(): array {
+		return array();
+	}
 }

modules/ppcp-button/src/Assets/SmartButtonInterface.php

@@ -22,16 +22,19 @@ interface SmartButtonInterface {
 	public function render_wrapper(): bool;
 
 	/**
-	 * Enqueues the necessary scripts.
-	 *
-	 * @return bool
+	 * Whether any of our scripts (for DCC or product, mini-cart, non-block cart/checkout) should be loaded.
 	 */
-	public function enqueue(): bool;
+	public function should_load_ppcp_script(): bool;
 
 	/**
-	 * Whether the running installation could save vault tokens or not.
-	 *
-	 * @return bool
+	 * Enqueues our scripts/styles (for DCC and product, mini-cart and non-block cart/checkout)
 	 */
-	public function can_save_vault_token(): bool;
+	public function enqueue(): void;
+
+	/**
+	 * The configuration for the smart buttons.
+	 *
+	 * @return array
+	 */
+	public function script_data(): array;
 }

modules/ppcp-button/src/ButtonModule.php

@@ -9,6 +9,11 @@ declare(strict_types=1);
 
 namespace WooCommerce\PayPalCommerce\Button;
 
+use WooCommerce\PayPalCommerce\Button\Endpoint\ApproveSubscriptionEndpoint;
+use WooCommerce\PayPalCommerce\Button\Endpoint\CartScriptParamsEndpoint;
+use WooCommerce\PayPalCommerce\Button\Endpoint\SaveCheckoutFormEndpoint;
+use WooCommerce\PayPalCommerce\Button\Endpoint\SimulateCartEndpoint;
+use WooCommerce\PayPalCommerce\Button\Endpoint\ValidateCheckoutEndpoint;
 use WooCommerce\PayPalCommerce\Vendor\Dhii\Container\ServiceProvider;
 use WooCommerce\PayPalCommerce\Vendor\Dhii\Modular\Module\ModuleInterface;
 use WooCommerce\PayPalCommerce\Button\Assets\SmartButtonInterface;
@@ -60,14 +65,12 @@ class ButtonModule implements ModuleInterface {
 		add_action(
 			'wp_enqueue_scripts',
 			static function () use ( $c ) {
-
 				$smart_button = $c->get( 'button.smart-button' );
-				/**
-				 * The Smart Button.
-				 *
-				 * @var SmartButtonInterface $smart_button
-				 */
-				$smart_button->enqueue();
+				assert( $smart_button instanceof SmartButtonInterface );
+
+				if ( $smart_button->should_load_ppcp_script() ) {
+					$smart_button->enqueue();
+				}
 			}
 		);
 
@@ -95,7 +98,7 @@ class ButtonModule implements ModuleInterface {
 	 *
 	 * @param ContainerInterface $container The Container.
 	 */
-	private function register_ajax_endpoints( ContainerInterface $container ) {
+	private function register_ajax_endpoints( ContainerInterface $container ): void {
 		add_action(
 			'wc_ajax_' . DataClientIdEndpoint::ENDPOINT,
 			static function () use ( $container ) {
@@ -118,6 +121,19 @@ class ButtonModule implements ModuleInterface {
 			}
 		);
 
+		add_action(
+			'wc_ajax_' . SimulateCartEndpoint::ENDPOINT,
+			static function () use ( $container ) {
+				$endpoint = $container->get( 'button.endpoint.simulate-cart' );
+				/**
+				 * The Simulate Cart Endpoint.
+				 *
+				 * @var SimulateCartEndpoint $endpoint
+				 */
+				$endpoint->handle_request();
+			}
+		);
+
 		add_action(
 			'wc_ajax_' . ChangeCartEndpoint::ENDPOINT,
 			static function () use ( $container ) {
@@ -144,6 +160,16 @@ class ButtonModule implements ModuleInterface {
 			}
 		);
 
+		add_action(
+			'wc_ajax_' . ApproveSubscriptionEndpoint::ENDPOINT,
+			static function () use ( $container ) {
+				$endpoint = $container->get( 'button.endpoint.approve-subscription' );
+				assert( $endpoint instanceof ApproveSubscriptionEndpoint );
+
+				$endpoint->handle_request();
+			}
+		);
+
 		add_action(
 			'wc_ajax_' . CreateOrderEndpoint::ENDPOINT,
 			static function () use ( $container ) {
@@ -156,6 +182,34 @@ class ButtonModule implements ModuleInterface {
 				$endpoint->handle_request();
 			}
 		);
+
+		add_action(
+			'wc_ajax_' . SaveCheckoutFormEndpoint::ENDPOINT,
+			static function () use ( $container ) {
+				$endpoint = $container->get( 'button.endpoint.save-checkout-form' );
+				assert( $endpoint instanceof SaveCheckoutFormEndpoint );
+
+				$endpoint->handle_request();
+			}
+		);
+
+		add_action(
+			'wc_ajax_' . ValidateCheckoutEndpoint::ENDPOINT,
+			static function () use ( $container ) {
+				$endpoint = $container->get( 'button.endpoint.validate-checkout' );
+				assert( $endpoint instanceof ValidateCheckoutEndpoint );
+				$endpoint->handle_request();
+			}
+		);
+
+		add_action(
+			'wc_ajax_' . CartScriptParamsEndpoint::ENDPOINT,
+			static function () use ( $container ) {
+				$endpoint = $container->get( 'button.endpoint.cart-script-params' );
+				assert( $endpoint instanceof CartScriptParamsEndpoint );
+				$endpoint->handle_request();
+			}
+		);
 	}
 
 	/**

modules/ppcp-button/src/Endpoint/AbstractCartEndpoint.php

@@ -0,0 +1,186 @@
+<?php
+/**
+ * Abstract class for cart Endpoints.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Endpoint
+ */
+
+namespace WooCommerce\PayPalCommerce\Button\Endpoint;
+
+use Exception;
+use Psr\Log\LoggerInterface;
+use WooCommerce\PayPalCommerce\ApiClient\Exception\PayPalApiException;
+use WooCommerce\PayPalCommerce\Button\Helper\CartProductsHelper;
+
+/**
+ * Abstract Class AbstractCartEndpoint
+ */
+abstract class AbstractCartEndpoint implements EndpointInterface {
+
+	const ENDPOINT = '';
+
+	/**
+	 * The current cart object.
+	 *
+	 * @var \WC_Cart
+	 */
+	protected $cart;
+
+	/**
+	 * The cart products helper.
+	 *
+	 * @var CartProductsHelper
+	 */
+	protected $cart_products;
+
+	/**
+	 * The request data helper.
+	 *
+	 * @var RequestData
+	 */
+	protected $request_data;
+
+	/**
+	 * The logger.
+	 *
+	 * @var LoggerInterface
+	 */
+	protected $logger;
+
+	/**
+	 * The tag to be added to logs.
+	 *
+	 * @var string
+	 */
+	protected $logger_tag = '';
+
+	/**
+	 * The nonce.
+	 *
+	 * @return string
+	 */
+	public static function nonce(): string {
+		return static::ENDPOINT;
+	}
+
+	/**
+	 * Handles the request.
+	 *
+	 * @return bool
+	 */
+	public function handle_request(): bool {
+		try {
+			return $this->handle_data();
+		} catch ( Exception $error ) {
+			$this->logger->error( 'Cart ' . $this->logger_tag . ' failed: ' . $error->getMessage() );
+
+			wp_send_json_error(
+				array(
+					'name'    => is_a( $error, PayPalApiException::class ) ? $error->name() : '',
+					'message' => $error->getMessage(),
+					'code'    => $error->getCode(),
+					'details' => is_a( $error, PayPalApiException::class ) ? $error->details() : array(),
+				)
+			);
+			return false;
+		}
+	}
+
+	/**
+	 * Handles the request data.
+	 *
+	 * @return bool
+	 * @throws Exception On error.
+	 */
+	abstract protected function handle_data(): bool;
+
+	/**
+	 * Adds products to cart.
+	 *
+	 * @param array $products Array of products to be added to cart.
+	 * @return bool
+	 * @throws Exception Add to cart methods throw an exception on fail.
+	 */
+	protected function add_products( array $products ): bool {
+		$this->cart->empty_cart( false );
+
+		try {
+			$this->cart_products->add_products( $products );
+		} catch ( Exception $e ) {
+			$this->handle_error();
+		}
+
+		return true;
+	}
+
+	/**
+	 * Handles errors.
+	 *
+	 * @param bool $send_response If this error handling should return the response.
+	 * @return void
+	 */
+	protected function handle_error( bool $send_response = true ): void {
+
+		$message = __(
+			'Something went wrong. Action aborted',
+			'woocommerce-paypal-payments'
+		);
+		$errors  = wc_get_notices( 'error' );
+		if ( count( $errors ) ) {
+			$message = array_reduce(
+				$errors,
+				static function ( string $add, array $error ): string {
+					return $add . $error['notice'] . ' ';
+				},
+				''
+			);
+			wc_clear_notices();
+		}
+
+		if ( $send_response ) {
+			wp_send_json_error(
+				array(
+					'name'    => '',
+					'message' => $message,
+					'code'    => 0,
+					'details' => array(),
+				)
+			);
+		}
+	}
+
+	/**
+	 * Returns product information from request data.
+	 *
+	 * @return array|false
+	 */
+	protected function products_from_request() {
+		$data     = $this->request_data->read_request( $this->nonce() );
+		$products = $this->cart_products->products_from_data( $data );
+		if ( ! $products ) {
+			wp_send_json_error(
+				array(
+					'name'    => '',
+					'message' => __(
+						'Necessary fields not defined. Action aborted.',
+						'woocommerce-paypal-payments'
+					),
+					'code'    => 0,
+					'details' => array(),
+				)
+			);
+			return false;
+		}
+
+		return $products;
+	}
+
+	/**
+	 * Removes stored cart items from WooCommerce cart.
+	 *
+	 * @return void
+	 */
+	protected function remove_cart_items(): void {
+		$this->cart_products->remove_cart_items();
+	}
+}

modules/ppcp-button/src/Endpoint/ApproveOrderEndpoint.php

@@ -180,7 +180,7 @@ class ApproveOrderEndpoint implements EndpointInterface {
 					);
 				}
 				$this->session_handler->replace_order( $order );
-				wp_send_json_success( $order );
+				wp_send_json_success();
 			}
 
 			if ( $this->order_helper->contains_physical_goods( $order ) && ! $order->status()->is( OrderStatus::APPROVED ) && ! $order->status()->is( OrderStatus::CREATED ) ) {
@@ -198,7 +198,7 @@ class ApproveOrderEndpoint implements EndpointInterface {
 			$this->session_handler->replace_funding_source( $funding_source );
 
 			$this->session_handler->replace_order( $order );
-			wp_send_json_success( $order );
+			wp_send_json_success();
 			return true;
 		} catch ( Exception $error ) {
 			$this->logger->error( 'Order approve failed: ' . $error->getMessage() );

modules/ppcp-button/src/Endpoint/ApproveSubscriptionEndpoint.php

@@ -0,0 +1,94 @@
+<?php
+/**
+ * Endpoint to handle PayPal Subscription created.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Endpoint
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Endpoint;
+
+use WooCommerce\PayPalCommerce\ApiClient\Endpoint\OrderEndpoint;
+use WooCommerce\PayPalCommerce\Button\Exception\RuntimeException;
+use WooCommerce\PayPalCommerce\Session\SessionHandler;
+
+/**
+ * Class ApproveSubscriptionEndpoint
+ */
+class ApproveSubscriptionEndpoint implements EndpointInterface {
+
+	const ENDPOINT = 'ppc-approve-subscription';
+
+	/**
+	 * The request data helper.
+	 *
+	 * @var RequestData
+	 */
+	private $request_data;
+
+	/**
+	 * The order endpoint.
+	 *
+	 * @var OrderEndpoint
+	 */
+	private $order_endpoint;
+
+	/**
+	 * The session handler.
+	 *
+	 * @var SessionHandler
+	 */
+	private $session_handler;
+
+	/**
+	 * ApproveSubscriptionEndpoint constructor.
+	 *
+	 * @param RequestData    $request_data The request data helper.
+	 * @param OrderEndpoint  $order_endpoint The order endpoint.
+	 * @param SessionHandler $session_handler The session handler.
+	 */
+	public function __construct(
+		RequestData $request_data,
+		OrderEndpoint $order_endpoint,
+		SessionHandler $session_handler
+	) {
+		$this->request_data    = $request_data;
+		$this->order_endpoint  = $order_endpoint;
+		$this->session_handler = $session_handler;
+	}
+
+	/**
+	 * The nonce.
+	 *
+	 * @return string
+	 */
+	public static function nonce(): string {
+		return self::ENDPOINT;
+	}
+
+	/**
+	 * Handles the request.
+	 *
+	 * @return bool
+	 * @throws RuntimeException When order not found or handling failed.
+	 */
+	public function handle_request(): bool {
+		$data = $this->request_data->read_request( $this->nonce() );
+		if ( ! isset( $data['order_id'] ) ) {
+			throw new RuntimeException(
+				__( 'No order id given', 'woocommerce-paypal-payments' )
+			);
+		}
+
+		$order = $this->order_endpoint->order( $data['order_id'] );
+		$this->session_handler->replace_order( $order );
+
+		if ( isset( $data['subscription_id'] ) ) {
+			WC()->session->set( 'ppcp_subscription_id', $data['subscription_id'] );
+		}
+
+		wp_send_json_success();
+		return true;
+	}
+}

modules/ppcp-button/src/Endpoint/CartScriptParamsEndpoint.php

@@ -0,0 +1,104 @@
+<?php
+/**
+ * The endpoint for returning the PayPal SDK Script parameters for the current cart.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Endpoint
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Endpoint;
+
+use Psr\Log\LoggerInterface;
+use Throwable;
+use WooCommerce\PayPalCommerce\ApiClient\Entity\Money;
+use WooCommerce\PayPalCommerce\Button\Assets\SmartButton;
+
+/**
+ * Class CartScriptParamsEndpoint.
+ */
+class CartScriptParamsEndpoint implements EndpointInterface {
+
+
+	const ENDPOINT = 'ppc-cart-script-params';
+
+	/**
+	 * The SmartButton.
+	 *
+	 * @var SmartButton
+	 */
+	private $smart_button;
+
+	/**
+	 * The logger.
+	 *
+	 * @var LoggerInterface
+	 */
+	private $logger;
+
+	/**
+	 * CartScriptParamsEndpoint constructor.
+	 *
+	 * @param SmartButton     $smart_button he SmartButton.
+	 * @param LoggerInterface $logger The logger.
+	 */
+	public function __construct(
+		SmartButton $smart_button,
+		LoggerInterface $logger
+	) {
+		$this->smart_button = $smart_button;
+		$this->logger       = $logger;
+	}
+
+	/**
+	 * Returns the nonce.
+	 *
+	 * @return string
+	 */
+	public static function nonce(): string {
+		return self::ENDPOINT;
+	}
+
+	/**
+	 * Handles the request.
+	 *
+	 * @return bool
+	 */
+	public function handle_request(): bool {
+		try {
+			if ( is_callable( 'wc_maybe_define_constant' ) ) {
+				wc_maybe_define_constant( 'WOOCOMMERCE_CART', true );
+			}
+
+			$script_data = $this->smart_button->script_data();
+
+			$total = (float) WC()->cart->get_total( 'numeric' );
+
+			// Shop settings.
+			$base_location     = wc_get_base_location();
+			$shop_country_code = $base_location['country'] ?? '';
+			$currency_code     = get_woocommerce_currency();
+
+			wp_send_json_success(
+				array(
+					'url_params'    => $script_data['url_params'],
+					'button'        => $script_data['button'],
+					'messages'      => $script_data['messages'],
+					'amount'        => WC()->cart->get_total( 'raw' ),
+
+					'total'         => $total,
+					'total_str'     => ( new Money( $total, $currency_code ) )->value_str(),
+					'currency_code' => $currency_code,
+					'country_code'  => $shop_country_code,
+				)
+			);
+
+			return true;
+		} catch ( Throwable $error ) {
+			$this->logger->error( "CartScriptParamsEndpoint execution failed. {$error->getMessage()} {$error->getFile()}:{$error->getLine()}" );
+
+			wp_send_json_error();
+			return false;
+		}
+	}
+}

modules/ppcp-button/src/Endpoint/ChangeCartEndpoint.php

@@ -11,26 +11,16 @@ namespace WooCommerce\PayPalCommerce\Button\Endpoint;
 
 use Exception;
 use Psr\Log\LoggerInterface;
-use WooCommerce\PayPalCommerce\ApiClient\Entity\PurchaseUnit;
-use WooCommerce\PayPalCommerce\ApiClient\Exception\PayPalApiException;
 use WooCommerce\PayPalCommerce\ApiClient\Factory\PurchaseUnitFactory;
-use WooCommerce\PayPalCommerce\Button\Exception\RuntimeException;
+use WooCommerce\PayPalCommerce\Button\Helper\CartProductsHelper;
 
 /**
  * Class ChangeCartEndpoint
  */
-class ChangeCartEndpoint implements EndpointInterface {
-
+class ChangeCartEndpoint extends AbstractCartEndpoint {
 
 	const ENDPOINT = 'ppc-change-cart';
 
-	/**
-	 * The current cart object.
-	 *
-	 * @var \WC_Cart
-	 */
-	private $cart;
-
 	/**
 	 * The current shipping object.
 	 *
@@ -38,13 +28,6 @@ class ChangeCartEndpoint implements EndpointInterface {
 	 */
 	private $shipping;
 
-	/**
-	 * The request data helper.
-	 *
-	 * @var RequestData
-	 */
-	private $request_data;
-
 	/**
 	 * The PurchaseUnit factory.
 	 *
@@ -52,20 +35,6 @@ class ChangeCartEndpoint implements EndpointInterface {
 	 */
 	private $purchase_unit_factory;
 
-	/**
-	 * The product data store.
-	 *
-	 * @var \WC_Data_Store
-	 */
-	private $product_data_store;
-
-	/**
-	 * The logger.
-	 *
-	 * @var LoggerInterface
-	 */
-	protected $logger;
-
 	/**
 	 * ChangeCartEndpoint constructor.
 	 *
@@ -73,7 +42,7 @@ class ChangeCartEndpoint implements EndpointInterface {
 	 * @param \WC_Shipping        $shipping The current WC shipping object.
 	 * @param RequestData         $request_data The request data helper.
 	 * @param PurchaseUnitFactory $purchase_unit_factory The PurchaseUnit factory.
-	 * @param \WC_Data_Store      $product_data_store The data store for products.
+	 * @param CartProductsHelper  $cart_products The cart products helper.
 	 * @param LoggerInterface     $logger The logger.
 	 */
 	public function __construct(
@@ -81,7 +50,7 @@ class ChangeCartEndpoint implements EndpointInterface {
 		\WC_Shipping $shipping,
 		RequestData $request_data,
 		PurchaseUnitFactory $purchase_unit_factory,
-		\WC_Data_Store $product_data_store,
+		CartProductsHelper $cart_products,
 		LoggerInterface $logger
 	) {
 
@@ -89,40 +58,10 @@ class ChangeCartEndpoint implements EndpointInterface {
 		$this->shipping              = $shipping;
 		$this->request_data          = $request_data;
 		$this->purchase_unit_factory = $purchase_unit_factory;
-		$this->product_data_store    = $product_data_store;
+		$this->cart_products         = $cart_products;
 		$this->logger                = $logger;
-	}
 
-	/**
-	 * The nonce.
-	 *
-	 * @return string
-	 */
-	public static function nonce(): string {
-		return self::ENDPOINT;
-	}
-
-	/**
-	 * Handles the request.
-	 *
-	 * @return bool
-	 */
-	public function handle_request(): bool {
-		try {
-			return $this->handle_data();
-		} catch ( Exception $error ) {
-			$this->logger->error( 'Cart updating failed: ' . $error->getMessage() );
-
-			wp_send_json_error(
-				array(
-					'name'    => is_a( $error, PayPalApiException::class ) ? $error->name() : '',
-					'message' => $error->getMessage(),
-					'code'    => $error->getCode(),
-					'details' => is_a( $error, PayPalApiException::class ) ? $error->details() : array(),
-				)
-			);
-			return false;
-		}
+		$this->logger_tag = 'updating';
 	}
 
 	/**
@@ -131,161 +70,25 @@ class ChangeCartEndpoint implements EndpointInterface {
 	 * @return bool
 	 * @throws Exception On error.
 	 */
-	private function handle_data(): bool {
-		$data     = $this->request_data->read_request( $this->nonce() );
-		$products = $this->products_from_data( $data );
+	protected function handle_data(): bool {
+		$this->cart_products->set_cart( $this->cart );
+
+		$products = $this->products_from_request();
+
 		if ( ! $products ) {
-			wp_send_json_error(
-				array(
-					'name'    => '',
-					'message' => __(
-						'Necessary fields not defined. Action aborted.',
-						'woocommerce-paypal-payments'
-					),
-					'code'    => 0,
-					'details' => array(),
-				)
-			);
 			return false;
 		}
 
 		$this->shipping->reset_shipping();
-		$this->cart->empty_cart( false );
-		$success = true;
-		foreach ( $products as $product ) {
-			$success = $success && ( ! $product['product']->is_type( 'variable' ) ) ?
-				$this->add_product( $product['product'], $product['quantity'] )
-				: $this->add_variable_product(
-					$product['product'],
-					$product['quantity'],
-					$product['variations']
-				);
-		}
-		if ( ! $success ) {
-			$this->handle_error();
-			return $success;
+
+		if ( ! $this->add_products( $products ) ) {
+			return false;
 		}
 
 		wp_send_json_success( $this->generate_purchase_units() );
-		return $success;
-	}
-
-	/**
-	 * Handles errors.
-	 *
-	 * @return bool
-	 */
-	private function handle_error(): bool {
-
-		$message = __(
-			'Something went wrong. Action aborted',
-			'woocommerce-paypal-payments'
-		);
-		$errors  = wc_get_notices( 'error' );
-		if ( count( $errors ) ) {
-			$message = array_reduce(
-				$errors,
-				static function ( string $add, array $error ): string {
-					return $add . $error['notice'] . ' ';
-				},
-				''
-			);
-			wc_clear_notices();
-		}
-
-		wp_send_json_error(
-			array(
-				'name'    => '',
-				'message' => $message,
-				'code'    => 0,
-				'details' => array(),
-			)
-		);
 		return true;
 	}
 
-	/**
-	 * Returns product information from an data array.
-	 *
-	 * @param array $data The data array.
-	 *
-	 * @return array|null
-	 */
-	private function products_from_data( array $data ) {
-
-		$products = array();
-
-		if (
-			! isset( $data['products'] )
-			|| ! is_array( $data['products'] )
-		) {
-			return null;
-		}
-		foreach ( $data['products'] as $product ) {
-			if ( ! isset( $product['quantity'] ) || ! isset( $product['id'] ) ) {
-				return null;
-			}
-
-			$wc_product = wc_get_product( (int) $product['id'] );
-
-			if ( ! $wc_product ) {
-				return null;
-			}
-			$products[] = array(
-				'product'    => $wc_product,
-				'quantity'   => (int) $product['quantity'],
-				'variations' => isset( $product['variations'] ) ? $product['variations'] : null,
-			);
-		}
-		return $products;
-	}
-
-	/**
-	 * Adds a product to the cart.
-	 *
-	 * @param \WC_Product $product The Product.
-	 * @param int         $quantity The Quantity.
-	 *
-	 * @return bool
-	 * @throws Exception When product could not be added.
-	 */
-	private function add_product( \WC_Product $product, int $quantity ): bool {
-		return false !== $this->cart->add_to_cart( $product->get_id(), $quantity );
-	}
-
-
-	/**
-	 * Adds variations to the cart.
-	 *
-	 * @param \WC_Product $product The Product.
-	 * @param int         $quantity The Quantity.
-	 * @param array       $post_variations The variations.
-	 *
-	 * @return bool
-	 * @throws Exception When product could not be added.
-	 */
-	private function add_variable_product(
-		\WC_Product $product,
-		int $quantity,
-		array $post_variations
-	): bool {
-
-		$variations = array();
-		foreach ( $post_variations as $key => $value ) {
-			$variations[ $value['name'] ] = $value['value'];
-		}
-
-		$variation_id = $this->product_data_store->find_matching_product_variation( $product, $variations );
-
-		// ToDo: Check stock status for variation.
-		return false !== $this->cart->add_to_cart(
-			$product->get_id(),
-			$quantity,
-			$variation_id,
-			$variations
-		);
-	}
-
 	/**
 	 * Based on the cart contents, the purchase units are created.
 	 *

modules/ppcp-button/src/Endpoint/CreateOrderEndpoint.php

@@ -19,20 +19,19 @@ use WooCommerce\PayPalCommerce\ApiClient\Entity\ApplicationContext;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\Money;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\Order;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\Payer;
-use WooCommerce\PayPalCommerce\ApiClient\Entity\PaymentMethod;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\PurchaseUnit;
 use WooCommerce\PayPalCommerce\ApiClient\Exception\PayPalApiException;
 use WooCommerce\PayPalCommerce\ApiClient\Exception\RuntimeException;
 use WooCommerce\PayPalCommerce\ApiClient\Factory\PayerFactory;
 use WooCommerce\PayPalCommerce\ApiClient\Factory\PurchaseUnitFactory;
 use WooCommerce\PayPalCommerce\ApiClient\Factory\ShippingPreferenceFactory;
+use WooCommerce\PayPalCommerce\ApiClient\Helper\OrderTransient;
 use WooCommerce\PayPalCommerce\Button\Exception\ValidationException;
 use WooCommerce\PayPalCommerce\Button\Validation\CheckoutFormValidator;
 use WooCommerce\PayPalCommerce\Button\Helper\EarlyOrderHandler;
 use WooCommerce\PayPalCommerce\Session\SessionHandler;
 use WooCommerce\PayPalCommerce\Subscription\FreeTrialHandlerTrait;
 use WooCommerce\PayPalCommerce\WcGateway\CardBillingMode;
-use WooCommerce\PayPalCommerce\WcGateway\Exception\NotFoundException;
 use WooCommerce\PayPalCommerce\WcGateway\Gateway\CardButtonGateway;
 use WooCommerce\PayPalCommerce\WcGateway\Gateway\CreditCardGateway;
 use WooCommerce\PayPalCommerce\WcGateway\Gateway\PayPalGateway;
@@ -138,6 +137,27 @@ class CreateOrderEndpoint implements EndpointInterface {
 	 */
 	protected $early_validation_enabled;
 
+	/**
+	 * The contexts that should have the Pay Now button.
+	 *
+	 * @var string[]
+	 */
+	private $pay_now_contexts;
+
+	/**
+	 * If true, the shipping methods are sent to PayPal allowing the customer to select it inside the popup.
+	 *
+	 * @var bool
+	 */
+	private $handle_shipping_in_paypal;
+
+	/**
+	 * The sources that do not cause issues about redirecting (on mobile, ...) and sometimes not returning back.
+	 *
+	 * @var string[]
+	 */
+	private $funding_sources_without_redirect;
+
 	/**
 	 * The logger.
 	 *
@@ -145,6 +165,13 @@ class CreateOrderEndpoint implements EndpointInterface {
 	 */
 	protected $logger;
 
+	/**
+	 * The form data, or empty if not available.
+	 *
+	 * @var array
+	 */
+	private $form = array();
+
 	/**
 	 * CreateOrderEndpoint constructor.
 	 *
@@ -159,6 +186,9 @@ class CreateOrderEndpoint implements EndpointInterface {
 	 * @param bool                      $registration_needed  Whether a new user must be registered during checkout.
 	 * @param string                    $card_billing_data_mode The value of card_billing_data_mode from the settings.
 	 * @param bool                      $early_validation_enabled Whether to execute WC validation of the checkout form.
+	 * @param string[]                  $pay_now_contexts The contexts that should have the Pay Now button.
+	 * @param bool                      $handle_shipping_in_paypal If true, the shipping methods are sent to PayPal allowing the customer to select it inside the popup.
+	 * @param string[]                  $funding_sources_without_redirect The sources that do not cause issues about redirecting (on mobile, ...) and sometimes not returning back.
 	 * @param LoggerInterface           $logger The logger.
 	 */
 	public function __construct(
@@ -173,21 +203,27 @@ class CreateOrderEndpoint implements EndpointInterface {
 		bool $registration_needed,
 		string $card_billing_data_mode,
 		bool $early_validation_enabled,
+		array $pay_now_contexts,
+		bool $handle_shipping_in_paypal,
+		array $funding_sources_without_redirect,
 		LoggerInterface $logger
 	) {
 
-		$this->request_data                = $request_data;
-		$this->purchase_unit_factory       = $purchase_unit_factory;
-		$this->shipping_preference_factory = $shipping_preference_factory;
-		$this->api_endpoint                = $order_endpoint;
-		$this->payer_factory               = $payer_factory;
-		$this->session_handler             = $session_handler;
-		$this->settings                    = $settings;
-		$this->early_order_handler         = $early_order_handler;
-		$this->registration_needed         = $registration_needed;
-		$this->card_billing_data_mode      = $card_billing_data_mode;
-		$this->early_validation_enabled    = $early_validation_enabled;
-		$this->logger                      = $logger;
+		$this->request_data                     = $request_data;
+		$this->purchase_unit_factory            = $purchase_unit_factory;
+		$this->shipping_preference_factory      = $shipping_preference_factory;
+		$this->api_endpoint                     = $order_endpoint;
+		$this->payer_factory                    = $payer_factory;
+		$this->session_handler                  = $session_handler;
+		$this->settings                         = $settings;
+		$this->early_order_handler              = $early_order_handler;
+		$this->registration_needed              = $registration_needed;
+		$this->card_billing_data_mode           = $card_billing_data_mode;
+		$this->early_validation_enabled         = $early_validation_enabled;
+		$this->pay_now_contexts                 = $pay_now_contexts;
+		$this->handle_shipping_in_paypal        = $handle_shipping_in_paypal;
+		$this->funding_sources_without_redirect = $funding_sources_without_redirect;
+		$this->logger                           = $logger;
 	}
 
 	/**
@@ -226,7 +262,13 @@ class CreateOrderEndpoint implements EndpointInterface {
 				}
 				$this->purchase_unit = $this->purchase_unit_factory->from_wc_order( $wc_order );
 			} else {
-				$this->purchase_unit = $this->purchase_unit_factory->from_wc_cart();
+				$this->purchase_unit = $this->purchase_unit_factory->from_wc_cart( null, $this->handle_shipping_in_paypal );
+
+				// Do not allow completion by webhooks when started via non-checkout buttons,
+				// it is needed only for some APMs in checkout.
+				if ( in_array( $data['context'], array( 'product', 'cart', 'cart-block' ), true ) ) {
+					$this->purchase_unit->set_custom_id( '' );
+				}
 
 				// The cart does not have any info about payment method, so we must handle free trial here.
 				if ( (
@@ -246,18 +288,20 @@ class CreateOrderEndpoint implements EndpointInterface {
 
 			$this->set_bn_code( $data );
 
-			$form_fields = $data['form'] ?? null;
+			if ( isset( $data['form'] ) ) {
+				$this->form = $data['form'];
+			}
 
 			if ( $this->early_validation_enabled
-				&& is_array( $form_fields )
+				&& $this->form
 				&& 'checkout' === $data['context']
 				&& in_array( $payment_method, array( PayPalGateway::ID, CardButtonGateway::ID ), true )
 			) {
-				$this->validate_form( $form_fields );
+				$this->validate_form( $this->form );
 			}
 
-			if ( 'pay-now' === $data['context'] && is_array( $form_fields ) && get_option( 'woocommerce_terms_page_id', '' ) !== '' ) {
-				$this->validate_paynow_form( $form_fields );
+			if ( 'pay-now' === $data['context'] && $this->form && get_option( 'woocommerce_terms_page_id', '' ) !== '' ) {
+				$this->validate_paynow_form( $this->form );
 			}
 
 			try {
@@ -268,11 +312,16 @@ class CreateOrderEndpoint implements EndpointInterface {
 			}
 
 			if ( 'checkout' === $data['context'] ) {
+				if ( $payment_method === PayPalGateway::ID && ! in_array( $funding_source, $this->funding_sources_without_redirect, true ) ) {
+					$this->session_handler->replace_order( $order );
+					$this->session_handler->replace_funding_source( $funding_source );
+				}
+
 				if (
 					! $this->early_order_handler->should_create_early_order()
 					|| $this->registration_needed
 					|| isset( $data['createaccount'] ) && '1' === $data['createaccount'] ) {
-					wp_send_json_success( $order->to_array() );
+					wp_send_json_success( $this->make_response( $order ) );
 				}
 
 				$this->early_order_handler->register_for_order( $order );
@@ -282,18 +331,23 @@ class CreateOrderEndpoint implements EndpointInterface {
 				$wc_order->update_meta_data( PayPalGateway::ORDER_ID_META_KEY, $order->id() );
 				$wc_order->update_meta_data( PayPalGateway::INTENT_META_KEY, $order->intent() );
 				$wc_order->save_meta_data();
+
+				do_action( 'woocommerce_paypal_payments_woocommerce_order_created', $wc_order, $order );
 			}
 
-			wp_send_json_success( $order->to_array() );
+			wp_send_json_success( $this->make_response( $order ) );
 			return true;
 
 		} catch ( ValidationException $error ) {
-			wp_send_json_error(
-				array(
-					'message' => $error->getMessage(),
-					'errors'  => $error->errors(),
-				)
+			$response = array(
+				'message' => $error->getMessage(),
+				'errors'  => $error->errors(),
+				'refresh' => isset( WC()->session->refresh_totals ),
 			);
+
+			unset( WC()->session->refresh_totals );
+
+			wp_send_json_error( $response );
 		} catch ( \RuntimeException $error ) {
 			$this->logger->error( 'Order creation failed: ' . $error->getMessage() );
 
@@ -339,7 +393,7 @@ class CreateOrderEndpoint implements EndpointInterface {
 			 * during the "onApprove"-JS callback or the webhook listener.
 			 */
 			if ( ! $this->early_order_handler->should_create_early_order() ) {
-				wp_send_json_success( $order->to_array() );
+				wp_send_json_success( $this->make_response( $order ) );
 			}
 			$this->early_order_handler->register_for_order( $order );
 			return $data;
@@ -382,6 +436,9 @@ class CreateOrderEndpoint implements EndpointInterface {
 			$funding_source
 		);
 
+		$action = in_array( $this->parsed_request_data['context'], $this->pay_now_contexts, true ) ?
+			ApplicationContext::USER_ACTION_PAY_NOW : ApplicationContext::USER_ACTION_CONTINUE;
+
 		if ( 'card' === $funding_source ) {
 			if ( CardBillingMode::MINIMAL_INPUT === $this->card_billing_data_mode ) {
 				if ( ApplicationContext::SHIPPING_PREFERENCE_SET_PROVIDED_ADDRESS === $shipping_preference ) {
@@ -407,7 +464,8 @@ class CreateOrderEndpoint implements EndpointInterface {
 				$shipping_preference,
 				$payer,
 				null,
-				$this->payment_method()
+				'',
+				$action
 			);
 		} catch ( PayPalApiException $exception ) {
 			// Looks like currently there is no proper way to validate the shipping address for PayPal,
@@ -428,8 +486,7 @@ class CreateOrderEndpoint implements EndpointInterface {
 					array( $this->purchase_unit ),
 					$shipping_preference,
 					$payer,
-					null,
-					$this->payment_method()
+					null
 				);
 			}
 
@@ -467,11 +524,9 @@ class CreateOrderEndpoint implements EndpointInterface {
 			$payer = $this->payer_factory->from_paypal_response( json_decode( wp_json_encode( $data['payer'] ) ) );
 		}
 
-		if ( ! $payer && isset( $data['form'] ) ) {
-			$form_fields = $data['form'];
-
-			if ( is_array( $form_fields ) && isset( $form_fields['billing_email'] ) && '' !== $form_fields['billing_email'] ) {
-				return $this->payer_factory->from_checkout_form( $form_fields );
+		if ( ! $payer && $this->form ) {
+			if ( isset( $this->form['billing_email'] ) && '' !== $this->form['billing_email'] ) {
+				return $this->payer_factory->from_checkout_form( $this->form );
 			}
 		}
 
@@ -493,24 +548,6 @@ class CreateOrderEndpoint implements EndpointInterface {
 		$this->api_endpoint->with_bn_code( $bn_code );
 	}
 
-	/**
-	 * Returns the PaymentMethod object for the order.
-	 *
-	 * @return PaymentMethod
-	 */
-	private function payment_method() : PaymentMethod {
-		try {
-			$payee_preferred = $this->settings->has( 'payee_preferred' ) && $this->settings->get( 'payee_preferred' ) ?
-				PaymentMethod::PAYEE_PREFERRED_IMMEDIATE_PAYMENT_REQUIRED
-				: PaymentMethod::PAYEE_PREFERRED_UNRESTRICTED;
-		} catch ( NotFoundException $exception ) {
-			$payee_preferred = PaymentMethod::PAYEE_PREFERRED_UNRESTRICTED;
-		}
-
-		$payment_method = new PaymentMethod( $payee_preferred );
-		return $payment_method;
-	}
-
 	/**
 	 * Checks whether the form fields are valid.
 	 *
@@ -541,4 +578,17 @@ class CreateOrderEndpoint implements EndpointInterface {
 			);
 		}
 	}
+
+	/**
+	 * Returns the response data for success response.
+	 *
+	 * @param Order $order The PayPal order.
+	 * @return array
+	 */
+	private function make_response( Order $order ): array {
+		return array(
+			'id'        => $order->id(),
+			'custom_id' => $order->purchase_units()[0]->custom_id(),
+		);
+	}
 }

modules/ppcp-button/src/Endpoint/RequestData.php

@@ -53,6 +53,11 @@ class RequestData {
 		}
 		$this->dequeue_nonce_fix();
 
+		if ( isset( $json['form_encoded'] ) ) {
+			$json['form'] = array();
+			parse_str( $json['form_encoded'], $json['form'] );
+		}
+
 		$sanitized = $this->sanitize( $json );
 		return $sanitized;
 	}
@@ -80,6 +85,10 @@ class RequestData {
 	private function sanitize( array $assoc_array ): array {
 		$data = array();
 		foreach ( (array) $assoc_array as $raw_key => $raw_value ) {
+			if ( $raw_key === 'form_encoded' ) {
+				$data[ $raw_key ] = $raw_value;
+				continue;
+			}
 			if ( ! is_array( $raw_value ) ) {
 				// Not sure if it is a good idea to sanitize everything at this level,
 				// but should be fine for now since we do not send any HTML or multi-line texts via ajax.

modules/ppcp-button/src/Endpoint/SaveCheckoutFormEndpoint.php

@@ -0,0 +1,94 @@
+<?php
+/**
+ * Saves the form data to the WC customer and session.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Endpoint
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Endpoint;
+
+use Exception;
+use Psr\Log\LoggerInterface;
+use WooCommerce\PayPalCommerce\Button\Helper\CheckoutFormSaver;
+
+/**
+ * Class SaveCheckoutFormEndpoint
+ */
+class SaveCheckoutFormEndpoint implements EndpointInterface {
+	const ENDPOINT = 'ppc-save-checkout-form';
+
+	/**
+	 * The Request Data Helper.
+	 *
+	 * @var RequestData
+	 */
+	private $request_data;
+
+	/**
+	 * The checkout form saver.
+	 *
+	 * @var CheckoutFormSaver
+	 */
+	private $checkout_form_saver;
+
+	/**
+	 * The logger.
+	 *
+	 * @var LoggerInterface
+	 */
+	protected $logger;
+
+	/**
+	 * SaveCheckoutFormEndpoint constructor.
+	 *
+	 * @param RequestData       $request_data The Request Data Helper.
+	 * @param CheckoutFormSaver $checkout_form_saver The checkout form saver.
+	 * @param LoggerInterface   $logger The logger.
+	 */
+	public function __construct(
+		RequestData $request_data,
+		CheckoutFormSaver $checkout_form_saver,
+		LoggerInterface $logger
+	) {
+
+		$this->request_data        = $request_data;
+		$this->checkout_form_saver = $checkout_form_saver;
+		$this->logger              = $logger;
+	}
+
+	/**
+	 * Returns the nonce.
+	 *
+	 * @return string
+	 */
+	public static function nonce(): string {
+		return self::ENDPOINT;
+	}
+
+	/**
+	 * Handles the request.
+	 *
+	 * @return bool
+	 */
+	public function handle_request(): bool {
+		try {
+			$data = $this->request_data->read_request( $this->nonce() );
+
+			$this->checkout_form_saver->save( $data['form'] );
+
+			wp_send_json_success();
+			return true;
+		} catch ( Exception $error ) {
+			$this->logger->error( 'Checkout form saving failed: ' . $error->getMessage() );
+
+			wp_send_json_error(
+				array(
+					'message' => $error->getMessage(),
+				)
+			);
+			return false;
+		}
+	}
+}

modules/ppcp-button/src/Endpoint/SimulateCartEndpoint.php

@@ -0,0 +1,178 @@
+<?php
+/**
+ * Endpoint to simulate adding products to the cart.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Endpoint
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Endpoint;
+
+use Exception;
+use Psr\Log\LoggerInterface;
+use WooCommerce\PayPalCommerce\ApiClient\Entity\Money;
+use WooCommerce\PayPalCommerce\Button\Assets\SmartButton;
+use WooCommerce\PayPalCommerce\Button\Helper\CartProductsHelper;
+
+/**
+ * Class SimulateCartEndpoint
+ */
+class SimulateCartEndpoint extends AbstractCartEndpoint {
+
+	const ENDPOINT = 'ppc-simulate-cart';
+
+	/**
+	 * The SmartButton.
+	 *
+	 * @var SmartButton
+	 */
+	private $smart_button;
+
+	/**
+	 * The WooCommerce real active cart.
+	 *
+	 * @var \WC_Cart|null
+	 */
+	private $real_cart = null;
+
+	/**
+	 * ChangeCartEndpoint constructor.
+	 *
+	 * @param SmartButton        $smart_button The SmartButton.
+	 * @param \WC_Cart           $cart The current WC cart object.
+	 * @param RequestData        $request_data The request data helper.
+	 * @param CartProductsHelper $cart_products The cart products helper.
+	 * @param LoggerInterface    $logger The logger.
+	 */
+	public function __construct(
+		SmartButton $smart_button,
+		\WC_Cart $cart,
+		RequestData $request_data,
+		CartProductsHelper $cart_products,
+		LoggerInterface $logger
+	) {
+		$this->smart_button  = $smart_button;
+		$this->cart          = clone $cart;
+		$this->request_data  = $request_data;
+		$this->cart_products = $cart_products;
+		$this->logger        = $logger;
+
+		$this->logger_tag = 'simulation';
+	}
+
+	/**
+	 * Handles the request data.
+	 *
+	 * @return bool
+	 * @throws Exception On error.
+	 */
+	protected function handle_data(): bool {
+		$products = $this->products_from_request();
+
+		if ( ! $products ) {
+			return false;
+		}
+
+		$this->replace_real_cart();
+
+		$this->add_products( $products );
+
+		$this->cart->calculate_totals();
+		$total = (float) $this->cart->get_total( 'numeric' );
+
+		$this->restore_real_cart();
+
+		// Process filters.
+		$pay_later_enabled           = true;
+		$pay_later_messaging_enabled = true;
+		$button_enabled              = true;
+
+		foreach ( $products as $product ) {
+			$context_data = array(
+				'product'     => $product['product'],
+				'order_total' => $total,
+			);
+
+			$pay_later_enabled           = $pay_later_enabled && $this->smart_button->is_pay_later_button_enabled_for_location( 'product', $context_data );
+			$pay_later_messaging_enabled = $pay_later_messaging_enabled && $this->smart_button->is_pay_later_messaging_enabled_for_location( 'product', $context_data );
+			$button_enabled              = $button_enabled && ! $this->smart_button->is_button_disabled( 'product', $context_data );
+		}
+
+		// Shop settings.
+		$base_location     = wc_get_base_location();
+		$shop_country_code = $base_location['country'];
+		$currency_code     = get_woocommerce_currency();
+
+		wp_send_json_success(
+			array(
+				'total'         => $total,
+				'total_str'     => ( new Money( $total, $currency_code ) )->value_str(),
+				'currency_code' => $currency_code,
+				'country_code'  => $shop_country_code,
+				'funding'       => array(
+					'paylater' => array(
+						'enabled' => $pay_later_enabled,
+					),
+				),
+				'button'        => array(
+					'is_disabled' => ! $button_enabled,
+				),
+				'messages'      => array(
+					'is_hidden' => ! $pay_later_messaging_enabled,
+				),
+			)
+		);
+		return true;
+	}
+
+	/**
+	 * Handles errors.
+	 *
+	 * @param bool $send_response If this error handling should return the response.
+	 * @return void
+	 *
+	 * phpcs:disable Generic.CodeAnalysis.UselessOverridingMethod.Found
+	 */
+	protected function handle_error( bool $send_response = false ): void {
+		parent::handle_error( $send_response );
+	}
+
+	/**
+	 * Replaces the real cart with the clone.
+	 *
+	 * @return void
+	 */
+	private function replace_real_cart() {
+		// Set WC default cart as the clone.
+		// Store a reference to the real cart.
+		$this->real_cart = WC()->cart;
+		WC()->cart       = $this->cart;
+		$this->cart_products->set_cart( $this->cart );
+	}
+
+	/**
+	 * Restores the real cart.
+	 * Currently, unsets the WC cart to prevent race conditions arising from it being persisted.
+	 *
+	 * @return void
+	 */
+	private function restore_real_cart() {
+		// Remove from cart because some plugins reserve resources internally when adding to cart.
+		$this->remove_cart_items();
+
+		if ( apply_filters( 'woocommerce_paypal_payments_simulate_cart_prevent_updates', true ) ) {
+			// Removes shutdown actions to prevent persisting session, transients and save cookies.
+			remove_all_actions( 'shutdown' );
+			unset( WC()->cart );
+		} else {
+			// Restores cart, may lead to race conditions.
+			if ( null !== $this->real_cart ) {
+				WC()->cart = $this->real_cart;
+			}
+		}
+
+		unset( $this->cart );
+	}
+
+}

modules/ppcp-button/src/Endpoint/ValidateCheckoutEndpoint.php

@@ -0,0 +1,110 @@
+<?php
+/**
+ * The endpoint for validating the checkout form.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Endpoint
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Endpoint;
+
+use Psr\Log\LoggerInterface;
+use Throwable;
+use WooCommerce\PayPalCommerce\Button\Exception\ValidationException;
+use WooCommerce\PayPalCommerce\Button\Validation\CheckoutFormValidator;
+
+/**
+ * Class ValidateCheckoutEndpoint.
+ */
+class ValidateCheckoutEndpoint implements EndpointInterface {
+
+
+	const ENDPOINT = 'ppc-validate-checkout';
+
+	/**
+	 * The Request Data Helper.
+	 *
+	 * @var RequestData
+	 */
+	private $request_data;
+
+	/**
+	 * The CheckoutFormValidator.
+	 *
+	 * @var CheckoutFormValidator
+	 */
+	private $checkout_form_validator;
+
+	/**
+	 * The logger.
+	 *
+	 * @var LoggerInterface
+	 */
+	private $logger;
+
+	/**
+	 * ValidateCheckoutEndpoint constructor.
+	 *
+	 * @param RequestData           $request_data The Request Data Helper.
+	 * @param CheckoutFormValidator $checkout_form_validator    The CheckoutFormValidator.
+	 * @param LoggerInterface       $logger The logger.
+	 */
+	public function __construct(
+		RequestData $request_data,
+		CheckoutFormValidator $checkout_form_validator,
+		LoggerInterface $logger
+	) {
+		$this->request_data            = $request_data;
+		$this->checkout_form_validator = $checkout_form_validator;
+		$this->logger                  = $logger;
+	}
+
+	/**
+	 * Returns the nonce.
+	 *
+	 * @return string
+	 */
+	public static function nonce(): string {
+		return self::ENDPOINT;
+	}
+
+	/**
+	 * Handles the request.
+	 *
+	 * @return bool
+	 */
+	public function handle_request(): bool {
+		try {
+			$data = $this->request_data->read_request( $this->nonce() );
+
+			$form_fields = $data['form'];
+
+			$this->checkout_form_validator->validate( $form_fields );
+
+			wp_send_json_success();
+
+			return true;
+		} catch ( ValidationException $exception ) {
+			$response = array(
+				'message' => $exception->getMessage(),
+				'errors'  => $exception->errors(),
+				'refresh' => isset( WC()->session->refresh_totals ),
+			);
+
+			unset( WC()->session->refresh_totals );
+
+			wp_send_json_error( $response );
+			return false;
+		} catch ( Throwable $error ) {
+			$this->logger->error( "Form validation execution failed. {$error->getMessage()} {$error->getFile()}:{$error->getLine()}" );
+
+			wp_send_json_error(
+				array(
+					'message' => $error->getMessage(),
+				)
+			);
+			return false;
+		}
+	}
+}

modules/ppcp-button/src/Helper/CartProductsHelper.php

@@ -0,0 +1,285 @@
+<?php
+/**
+ * Handles the adding of products to WooCommerce cart.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Helper
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Helper;
+
+use Exception;
+use WC_Cart;
+use WC_Data_Store;
+
+/**
+ * Class CartProductsHelper
+ */
+class CartProductsHelper {
+
+	/**
+	 * The cart
+	 *
+	 * @var ?WC_Cart
+	 */
+	private $cart;
+
+	/**
+	 * The product data store.
+	 *
+	 * @var WC_Data_Store
+	 */
+	protected $product_data_store;
+
+	/**
+	 * The added cart item IDs
+	 *
+	 * @var array
+	 */
+	private $cart_item_keys = array();
+
+	/**
+	 * CheckoutFormSaver constructor.
+	 *
+	 * @param WC_Data_Store $product_data_store The data store for products.
+	 */
+	public function __construct(
+		WC_Data_Store $product_data_store
+	) {
+		$this->product_data_store = $product_data_store;
+	}
+
+	/**
+	 * Sets a new cart instance.
+	 *
+	 * @param WC_Cart $cart The cart.
+	 * @return void
+	 */
+	public function set_cart( WC_Cart $cart ): void {
+		$this->cart = $cart;
+	}
+
+	/**
+	 * Returns products information from a data array.
+	 *
+	 * @param array $data The data array.
+	 *
+	 * @return array|null
+	 */
+	public function products_from_data( array $data ): ?array {
+
+		$products = array();
+
+		if (
+			! isset( $data['products'] )
+			|| ! is_array( $data['products'] )
+		) {
+			return null;
+		}
+		foreach ( $data['products'] as $product ) {
+			$product = $this->product_from_data( $product );
+			if ( $product ) {
+				$products[] = $product;
+			}
+		}
+		return $products;
+	}
+
+	/**
+	 * Returns product information from a data array.
+	 *
+	 * @param array $product The product data array, usually provided by the product page form.
+	 * @return array|null
+	 */
+	public function product_from_data( array $product ): ?array {
+		if ( ! isset( $product['quantity'] ) || ! isset( $product['id'] ) ) {
+			return null;
+		}
+
+		$wc_product = wc_get_product( (int) $product['id'] );
+
+		if ( ! $wc_product ) {
+			return null;
+		}
+		return array(
+			'product'    => $wc_product,
+			'quantity'   => (int) $product['quantity'],
+			'variations' => $product['variations'] ?? null,
+			'booking'    => $product['booking'] ?? null,
+			'extra'      => $product['extra'] ?? null,
+		);
+	}
+
+	/**
+	 * Adds products to cart.
+	 *
+	 * @param array $products Array of products to be added to cart.
+	 * @return bool
+	 * @throws Exception Add to cart methods throw an exception on fail.
+	 */
+	public function add_products( array $products ): bool {
+		$success = true;
+		foreach ( $products as $product ) {
+
+			// Add extras to POST, they are usually added by custom plugins.
+			if ( $product['extra'] && is_array( $product['extra'] ) ) {
+				// Handle cases like field[].
+				$query = http_build_query( $product['extra'] );
+				parse_str( $query, $extra );
+
+				foreach ( $extra as $key => $value ) {
+					$_POST[ $key ] = $value;
+				}
+			}
+
+			if ( $product['product']->is_type( 'booking' ) ) {
+				$success = $success && $this->add_booking_product(
+					$product['product'],
+					$product['booking']
+				);
+			} elseif ( $product['product']->is_type( 'variable' ) ) {
+				$success = $success && $this->add_variable_product(
+					$product['product'],
+					$product['quantity'],
+					$product['variations']
+				);
+			} else {
+				$success = $success && $this->add_product(
+					$product['product'],
+					$product['quantity']
+				);
+			}
+		}
+
+		if ( ! $success ) {
+			throw new Exception( 'Error adding products to cart.' );
+		}
+
+		return true;
+	}
+
+	/**
+	 * Adds a product to the cart.
+	 *
+	 * @param \WC_Product $product The Product.
+	 * @param int         $quantity The Quantity.
+	 *
+	 * @return bool
+	 * @throws Exception When product could not be added.
+	 */
+	public function add_product( \WC_Product $product, int $quantity ): bool {
+		if ( ! $this->cart ) {
+			throw new Exception( 'Cart not set.' );
+		}
+
+		$cart_item_key = $this->cart->add_to_cart( $product->get_id(), $quantity );
+
+		if ( $cart_item_key ) {
+			$this->cart_item_keys[] = $cart_item_key;
+		}
+		return false !== $cart_item_key;
+	}
+
+	/**
+	 * Adds variations to the cart.
+	 *
+	 * @param \WC_Product $product The Product.
+	 * @param int         $quantity The Quantity.
+	 * @param array       $post_variations The variations.
+	 *
+	 * @return bool
+	 * @throws Exception When product could not be added.
+	 */
+	public function add_variable_product(
+		\WC_Product $product,
+		int $quantity,
+		array $post_variations
+	): bool {
+		if ( ! $this->cart ) {
+			throw new Exception( 'Cart not set.' );
+		}
+
+		$variations = array();
+		foreach ( $post_variations as $key => $value ) {
+			$variations[ $value['name'] ] = $value['value'];
+		}
+
+		$variation_id = $this->product_data_store->find_matching_product_variation( $product, $variations );
+
+		// ToDo: Check stock status for variation.
+		$cart_item_key = $this->cart->add_to_cart(
+			$product->get_id(),
+			$quantity,
+			$variation_id,
+			$variations
+		);
+
+		if ( $cart_item_key ) {
+			$this->cart_item_keys[] = $cart_item_key;
+		}
+		return false !== $cart_item_key;
+	}
+
+	/**
+	 * Adds booking to the cart.
+	 *
+	 * @param \WC_Product $product The Product.
+	 * @param array       $data Data used by the booking plugin.
+	 *
+	 * @return bool
+	 * @throws Exception When product could not be added.
+	 */
+	public function add_booking_product(
+		\WC_Product $product,
+		array $data
+	): bool {
+		if ( ! $this->cart ) {
+			throw new Exception( 'Cart not set.' );
+		}
+
+		if ( ! is_callable( 'wc_bookings_get_posted_data' ) ) {
+			return false;
+		}
+
+		$cart_item_data = array(
+			'booking' => wc_bookings_get_posted_data( $data, $product ),
+		);
+
+		$cart_item_key = $this->cart->add_to_cart( $product->get_id(), 1, 0, array(), $cart_item_data );
+
+		if ( $cart_item_key ) {
+			$this->cart_item_keys[] = $cart_item_key;
+		}
+		return false !== $cart_item_key;
+	}
+
+	/**
+	 * Removes stored cart items from WooCommerce cart.
+	 *
+	 * @return void
+	 * @throws Exception Throws if there's a failure removing the cart items.
+	 */
+	public function remove_cart_items(): void {
+		if ( ! $this->cart ) {
+			throw new Exception( 'Cart not set.' );
+		}
+
+		foreach ( $this->cart_item_keys as $cart_item_key ) {
+			if ( ! $cart_item_key ) {
+				continue;
+			}
+			$this->cart->remove_cart_item( $cart_item_key );
+		}
+	}
+
+	/**
+	 * Returns the cart item keys of the items added to cart.
+	 *
+	 * @return array
+	 */
+	public function cart_item_keys(): array {
+		return $this->cart_item_keys;
+	}
+
+}

modules/ppcp-button/src/Helper/CheckoutFormSaver.php

@@ -0,0 +1,53 @@
+<?php
+/**
+ * Saves the form data to the WC customer and session.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Helper
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Helper;
+
+use WC_Checkout;
+use WooCommerce\PayPalCommerce\Session\SessionHandler;
+
+/**
+ * Class CheckoutFormSaver
+ */
+class CheckoutFormSaver extends WC_Checkout {
+	/**
+	 * The Session handler.
+	 *
+	 * @var SessionHandler
+	 */
+	private $session_handler;
+
+	/**
+	 * CheckoutFormSaver constructor.
+	 *
+	 * @param SessionHandler $session_handler The session handler.
+	 */
+	public function __construct(
+		SessionHandler $session_handler
+	) {
+		$this->session_handler = $session_handler;
+	}
+
+	/**
+	 * Saves the form data to the WC customer and session.
+	 *
+	 * @param array $data The form data.
+	 * @return void
+	 */
+	public function save( array $data ) {
+		foreach ( $data as $key => $value ) {
+			$_POST[ $key ] = $value;
+		}
+		$data = $this->get_posted_data();
+
+		$this->update_session( $data );
+
+		$this->session_handler->replace_checkout_form( $data );
+	}
+}

modules/ppcp-button/src/Helper/ContextTrait.php

@@ -0,0 +1,128 @@
+<?php
+/**
+ * Helper trait for context.
+ *
+ * @package WooCommerce\PayPalCommerce\Button\Helper
+ */
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Button\Helper;
+
+use WooCommerce\PayPalCommerce\ApiClient\Entity\OrderStatus;
+
+trait ContextTrait {
+	/**
+	 * Checks WC is_checkout() + WC checkout ajax requests.
+	 */
+	private function is_checkout(): bool {
+		if ( is_checkout() ) {
+			return true;
+		}
+
+		/**
+		 * The filter returning whether to detect WC checkout ajax requests.
+		 */
+		if ( apply_filters( 'ppcp_check_ajax_checkout', true ) ) {
+			// phpcs:ignore WordPress.Security
+			$wc_ajax = $_GET['wc-ajax'] ?? '';
+			if ( in_array( $wc_ajax, array( 'update_order_review' ), true ) ) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * The current context.
+	 *
+	 * @return string
+	 */
+	protected function context(): string {
+		if ( is_product() || wc_post_content_has_shortcode( 'product_page' ) ) {
+
+			// Do this check here instead of reordering outside conditions.
+			// In order to have more control over the context.
+			if ( $this->is_checkout() && ! $this->is_paypal_continuation() ) {
+				return 'checkout';
+			}
+
+			return 'product';
+		}
+
+		// has_block may not work if called too early, such as during the block registration.
+		if ( has_block( 'woocommerce/cart' ) ) {
+			return 'cart-block';
+		}
+
+		if ( is_cart() ) {
+			return 'cart';
+		}
+
+		if ( is_checkout_pay_page() ) {
+			return 'pay-now';
+		}
+
+		if ( has_block( 'woocommerce/checkout' ) ) {
+			return 'checkout-block';
+		}
+
+		if ( $this->is_checkout() && ! $this->is_paypal_continuation() ) {
+			return 'checkout';
+		}
+
+		return 'mini-cart';
+	}
+
+	/**
+	 * The current location.
+	 *
+	 * @return string
+	 */
+	protected function location(): string {
+		$context = $this->context();
+		if ( $context !== 'mini-cart' ) {
+			return $context;
+		}
+
+		if ( is_shop() || is_product_category() ) {
+			return 'shop';
+		}
+
+		if ( is_front_page() ) {
+			return 'home';
+		}
+
+		return '';
+	}
+
+	/**
+	 * Checks if PayPal payment was already initiated (on the product or cart pages).
+	 *
+	 * @return bool
+	 */
+	private function is_paypal_continuation(): bool {
+		$order = $this->session_handler->order();
+		if ( ! $order ) {
+			return false;
+		}
+
+		if ( ! $order->status()->is( OrderStatus::APPROVED )
+			&& ! $order->status()->is( OrderStatus::COMPLETED )
+		) {
+			return false;
+		}
+
+		$source = $order->payment_source();
+		if ( $source && $source->card() ) {
+			return false; // Ignore for DCC.
+		}
+
+		if ( 'card' === $this->session_handler->funding_source() ) {
+			return false; // Ignore for card buttons.
+		}
+
+		return true;
+	}
+}

modules/ppcp-button/src/Helper/EarlyOrderHandler.php

@@ -11,19 +11,17 @@ namespace WooCommerce\PayPalCommerce\Button\Helper;
 
 use WooCommerce\PayPalCommerce\ApiClient\Entity\Order;
 use WooCommerce\PayPalCommerce\ApiClient\Exception\PayPalApiException;
+use WooCommerce\PayPalCommerce\ApiClient\Helper\OrderTransient;
 use WooCommerce\PayPalCommerce\Onboarding\State;
 use WooCommerce\PayPalCommerce\Session\SessionHandler;
 use WooCommerce\PayPalCommerce\WcGateway\Gateway\PayPalGateway;
 use WooCommerce\PayPalCommerce\WcGateway\Processor\OrderProcessor;
-use WooCommerce\PayPalCommerce\Webhooks\Handler\PrefixTrait;
 
 /**
  * Class EarlyOrderHandler
  */
 class EarlyOrderHandler {
 
-	use PrefixTrait;
-
 	/**
 	 * The State.
 	 *
@@ -51,19 +49,16 @@ class EarlyOrderHandler {
 	 * @param State          $state The State.
 	 * @param OrderProcessor $order_processor The Order Processor.
 	 * @param SessionHandler $session_handler The Session Handler.
-	 * @param string         $prefix The Prefix.
 	 */
 	public function __construct(
 		State $state,
 		OrderProcessor $order_processor,
-		SessionHandler $session_handler,
-		string $prefix
+		SessionHandler $session_handler
 	) {
 
 		$this->state           = $state;
 		$this->order_processor = $order_processor;
 		$this->session_handler = $session_handler;
-		$this->prefix          = $prefix;
 	}
 
 	/**
@@ -101,7 +96,7 @@ class EarlyOrderHandler {
 		$order_id = false;
 		foreach ( $order->purchase_units() as $purchase_unit ) {
 			if ( $purchase_unit->custom_id() === sanitize_text_field( wp_unslash( $_REQUEST['ppcp-resume-order'] ) ) ) {
-				$order_id = (int) $this->sanitize_custom_id( $purchase_unit->custom_id() );
+				$order_id = (int) $purchase_unit->custom_id();
 			}
 		}
 		if ( $order_id === $resume_order_id ) {
@@ -169,6 +164,10 @@ class EarlyOrderHandler {
 		/**
 		 * Patch Order so we have the \WC_Order id added.
 		 */
-		return $this->order_processor->patch_order( $wc_order, $order );
+		$order = $this->order_processor->patch_order( $wc_order, $order );
+
+		do_action( 'woocommerce_paypal_payments_woocommerce_order_created', $wc_order, $order );
+
+		return $order;
 	}
 }

modules/ppcp-button/src/Validation/CheckoutFormValidator.php

@@ -27,20 +27,91 @@ class CheckoutFormValidator extends WC_Checkout {
 	public function validate( array $data ) {
 		$errors = new WP_Error();
 
-		// Some plugins check their fields using $_POST,
+		// Some plugins check their fields using $_POST or $_REQUEST,
 		// also WC terms checkbox https://github.com/woocommerce/woocommerce/issues/35328 .
 		foreach ( $data as $key => $value ) {
-			$_POST[ $key ] = $value;
+			$_POST[ $key ]    = $value;
+			$_REQUEST[ $key ] = $value;
 		}
-		// And we must call get_posted_data because it handles the shipping address.
-		$data = $this->get_posted_data();
 
-		// It throws some notices when checking fields etc., also from other plugins via hooks.
-		// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
-		@$this->validate_checkout( $data, $errors );
+		// Looks like without this WC()->shipping->get_packages() is empty which is used by some plugins.
+		WC()->cart->calculate_shipping();
 
-		if ( $errors->has_errors() ) {
-			throw new ValidationException( $errors->get_error_messages() );
+		// Some plugins/filters check is_checkout().
+		$is_checkout = function () {
+			return true;
+		};
+		add_filter( 'woocommerce_is_checkout', $is_checkout );
+		try {
+			// And we must call get_posted_data because it handles the shipping address.
+			$data = $this->get_posted_data();
+
+			// It throws some notices when checking fields etc., also from other plugins via hooks.
+			// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
+			@$this->validate_checkout( $data, $errors );
+		} finally {
+			remove_filter( 'woocommerce_is_checkout', $is_checkout );
+		}
+
+		if (
+			apply_filters( 'woocommerce_paypal_payments_early_wc_checkout_account_creation_validation_enabled', true ) &&
+			! is_user_logged_in() && ( $this->is_registration_required() || ! empty( $data['createaccount'] ) )
+		) {
+			$username = ! empty( $data['account_username'] ) ? $data['account_username'] : '';
+			$email    = $data['billing_email'] ?? '';
+
+			if ( email_exists( $email ) ) {
+				$errors->add(
+					'registration-error-email-exists',
+					apply_filters(
+						'woocommerce_registration_error_email_exists',
+						// phpcs:ignore WordPress.WP.I18n.TextDomainMismatch
+						__( 'An account is already registered with your email address. <a href="#" class="showlogin">Please log in.</a>', 'woocommerce' ),
+						$email
+					)
+				);
+			}
+
+			if ( $username ) { // Empty username is already checked in validate_checkout, and it can be generated.
+				$username = sanitize_user( $username );
+				if ( empty( $username ) || ! validate_username( $username ) ) {
+					$errors->add(
+						'registration-error-invalid-username',
+						// phpcs:ignore WordPress.WP.I18n.TextDomainMismatch
+						__( 'Please enter a valid account username.', 'woocommerce' )
+					);
+				}
+
+				if ( username_exists( $username ) ) {
+					$errors->add(
+						'registration-error-username-exists',
+						// phpcs:ignore WordPress.WP.I18n.TextDomainMismatch
+						__( 'An account is already registered with that username. Please choose another.', 'woocommerce' )
+					);
+				}
+			}
+		}
+
+		// Some plugins call wc_add_notice directly.
+		// We should retrieve such notices, and also clear them to avoid duplicates	later.
+		// TODO: Normally WC converts the messages from validate_checkout into notices,
+		// maybe we should do the same for consistency, but it requires lots of changes in the way we handle/output errors.
+		$messages = array_merge(
+			$errors->get_error_messages(),
+			array_map(
+				function ( array $notice ): string {
+					return $notice['notice'];
+				},
+				wc_get_notices( 'error' )
+			)
+		);
+
+		if ( wc_notice_count( 'error' ) > 0 ) {
+			wc_clear_notices();
+		}
+
+		if ( $messages ) {
+			throw new ValidationException( $messages );
 		}
 	}
 }