Create basic checkout permalink w/ products and coupon support

class-wc-facebookcommerce.php

@@ -63,6 +63,9 @@ class WC_Facebookcommerce extends WooCommerce\Facebook\Framework\Plugin {
 	/** @var WooCommerce\Facebook\AJAX Ajax handler instance */
 	private $ajax;
 
+	/** @var WooCommerce\Facebook\Checkout */
+	private $checkout;
+
 	/** @var WooCommerce\Facebook\Products\Feed product feed handler */
 	private $product_feed;
 
@@ -184,6 +187,7 @@ public function init() {
 			$this->heartbeat = new Heartbeat( WC()->queue() );
 			$this->heartbeat->init();
 
+			$this->checkout           			 = new WooCommerce\Facebook\Checkout();
 			$this->product_feed              = new WooCommerce\Facebook\Products\Feed();
 			$this->products_stock_handler    = new WooCommerce\Facebook\Products\Stock();
 			$this->products_sync_handler     = new WooCommerce\Facebook\Products\Sync();

includes/Checkout.php

@@ -0,0 +1,145 @@
+<?php
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved
+ *
+ * This source code is licensed under the license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @package FacebookCommerce
+ */
+
+namespace WooCommerce\Facebook;
+
+defined( 'ABSPATH' ) || exit;
+
+/**
+ * The checkout permalink.
+ *
+ * @since 3.3.0
+ */
+class Checkout {
+
+	/**
+	 * Checkout constructor.
+	 *
+	 * @since 3.3.0
+	 */
+	public function __construct() {
+		// add the necessary action and filter hooks
+		$this->add_hooks();
+	}
+
+	/**
+	 * Adds the necessary action and filter hooks.
+	 *
+	 * @since 3.3.0
+	 */
+	public function add_hooks() {
+		// add the rewrite rule for the checkout permalink
+		add_action( 'init', array( $this, 'add_checkout_permalink_rewrite_rule' ) );
+
+		// add the query var for the checkout permalink
+		add_filter( 'query_vars', array( $this, 'add_checkout_permalink_query_var' ) );
+
+		// load the checkout permalink template
+		add_filter( 'template_include', array( $this, 'load_checkout_permalink_template' ) );
+
+		// flush rewrite rules when plugin is activated
+		register_activation_hook( __FILE__, array( $this, 'flush_rewrite_rules_on_activation' ) );
+
+		// flush rewrite rules when plugin is deactivated
+		register_deactivation_hook( __FILE__, array( $this, 'flush_rewrite_rules_on_deactivation' ) );
+	}
+
+	/**
+	 * Adds a rewrite rule for the checkout permalink.
+	 *
+	 * @since 3.3.0
+	 */
+	public function add_checkout_permalink_rewrite_rule() {
+		add_rewrite_rule( '^fb-checkout/?$', 'index.php?fb_checkout=1', 'top' );
+	}
+
+	/**
+	 * Adds query vars for the checkout permalink.
+	 *
+	 * @since 3.3.0
+	 *
+	 * @param array $vars
+	 * @return array
+	 */
+	public function add_checkout_permalink_query_var( $vars ) {
+		// Add 'fb_checkout' as a query var
+		$vars[] = 'fb_checkout';
+
+		// Add 'products' as a query var
+		$vars[] = 'products';
+
+		// Add 'coupon' as a query var
+		$vars[] = 'coupon';
+
+		return $vars;
+	}
+
+	/**
+	 * Loads the checkout permalink template.
+	 *
+	 * @since 3.3.0
+	 */
+	public function load_checkout_permalink_template() {
+		if ( get_query_var( 'fb_checkout' ) ) {
+			// Clear the WooCommerce cart
+			WC()->cart->empty_cart();
+
+			// Get the 'products' query parameter
+			$products_param = get_query_var( 'products' );
+
+			if ( $products_param ) {
+				// Split multiple products by comma
+				$products = explode( ',', $products_param );
+
+				foreach ( $products as $product ) {
+					// Parse each product ID and quantity
+					list($product_id, $quantity) = explode( ':', $product );
+
+					// Validate and add the product to the cart
+					if ( is_numeric( $product_id ) && is_numeric( $quantity ) && $quantity > 0 ) {
+						WC()->cart->add_to_cart( $product_id, $quantity );
+					}
+				}
+			}
+
+			// Get the 'coupon' query parameter
+			$coupon_code = get_query_var( 'coupon' );
+
+			if ( $coupon_code ) {
+				// Apply the coupon to the cart
+				WC()->cart->apply_coupon( sanitize_text_field( $coupon_code ) );
+			}
+
+			// Use a custom template file
+			include plugin_dir_path( __FILE__ ) . 'Templates/CheckoutTemplate.php';
+
+			exit;
+		}
+	}
+
+	/**
+	 * Flushes rewrite rules when the plugin is activated.
+	 *
+	 * @since 3.3.0
+	 */
+	public function flush_rewrite_rules_on_activation() {
+		$this->add_checkout_permalink_rewrite_rule();
+		flush_rewrite_rules();
+	}
+
+	/**
+	 * Flushes rewrite rules when the plugin is deactivated.
+	 *
+	 * @since 3.3.0
+	 */
+	public function flush_rewrite_rules_on_deactivation() {
+		flush_rewrite_rules();
+	}
+}

includes/Templates/CheckoutTemplate.php

@@ -0,0 +1,28 @@
+<?php
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved
+ *
+ * This source code is licensed under the license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * Template Name: Checkout Template
+ *
+ * @package FacebookCommerce
+ */
+
+namespace WooCommerce\Facebook\Templates;
+
+defined( 'ABSPATH' ) || exit;
+
+get_header(); ?>
+
+<div id="primary" class="content-area">
+	<main id="main" class="site-main" role="main">
+		<?php
+		// Display the WooCommerce cart
+		echo do_shortcode( '[woocommerce_checkout]' );
+		?>
+	</main><!-- .site-main -->
+</div><!-- .content-area -->
+
+<?php get_footer(); ?>