smarty-gtm-events-for-woocommerce.php

<?php
/**
 * Plugin Name:             SM - GTM Events for WooCommerce
 * Plugin URI:              https://github.com/mnestorov/smarty-gtm-events-for-woocommerce
 * Description:             Pushes WooCommerce events to Google Tag Manager's dataLayer.
 * Version:                 1.0.3
 * Author:                  Martin Nestorov
 * Author URI:              https://github.com/mnestorov
 * License:                 GPL-2.0+
 * License URI:             http://www.gnu.org/licenses/gpl-2.0.txt
 * Text Domain:             smarty-gtm-events-for-woocommerce
 * Domain Path:             /languages
 * WC requires at least:    3.5.0
 * WC tested up to:         9.6.0
 * Requires Plugins:		woocommerce
 */

// If this file is called directly, abort.
if (!defined('WPINC')) {
	die;
}

/**
 * HPOS Compatibility Declaration.
 *
 * This ensures that the plugin explicitly declares compatibility with 
 * WooCommerce's High-Performance Order Storage (HPOS).
 * 
 * HPOS replaces the traditional `wp_posts` and `wp_postmeta` storage system 
 * for orders with a dedicated database table structure, improving scalability 
 * and performance.
 * 
 * More details:
 * - WooCommerce HPOS Documentation: 
 *   https://developer.woocommerce.com/2022/09/12/high-performance-order-storage-in-woocommerce/
 * - Declaring Plugin Compatibility: 
 *   https://github.com/woocommerce/woocommerce/wiki/High-Performance-Order-Storage-Upgrade-Recipe-Book#how-to-declare-compatibility
 */
add_action('before_woocommerce_init', function() {
    if (class_exists('\Automattic\WooCommerce\Utilities\FeaturesUtil')) {
        \Automattic\WooCommerce\Utilities\FeaturesUtil::declare_compatibility('custom_order_tables', __FILE__, true);
    }
});

// Define your secret key to clear the logs.
define('SMARTY_GTM_CLEAR_LOGS_SECRET', 'your-unique-secret-key');

if (!function_exists('smarty_gtm_get_nonce')) {
    /**
     * Generate and return the same nonce for both admin and front-end scripts.
     *
     * @return string The generated nonce.
     */
    function smarty_gtm_get_nonce() {
        return wp_create_nonce('smarty_gtm_events_nonce');
    }
}

if (!function_exists('smarty_gtm_enqueue_admin_scripts')) {
    /**
     * Enqueues admin scripts and styles for the settings page.
     *
     * This function enqueues the necessary JavaScript and CSS files for the
     * admin settings pages of the Google Feed Generator plugin.
     * It also localizes the script to pass AJAX-related data to the JavaScript file.
     *
     * @param string $hook_suffix The current admin page hook suffix.
     */
    function smarty_gtm_enqueue_admin_scripts($hook_suffix) {
        // Only add to the admin page of the plugin
        if ('woocommerce_page_smarty-gtm-settings' !== $hook_suffix) {
            return;
        }

        wp_enqueue_script('smarty-gtm-admin-js', plugin_dir_url(__FILE__) . 'js/smarty-gtm-admin.js', array('jquery'), '1.0.0', true);
        wp_enqueue_style('smarty-gtm-admin-css', plugin_dir_url(__FILE__) . 'css/smarty-gtm-admin.css', array(), '1.0.0');
        wp_localize_script(
            'smarty-gtm-admin-js',
            'smartyGtmEvents',
            array(
                'ajaxUrl' => admin_url('admin-ajax.php'),
                'siteUrl' => site_url(),
                'nonce'   => smarty_gtm_get_nonce(),
            )
        );
    }
    add_action('admin_enqueue_scripts', 'smarty_gtm_enqueue_admin_scripts');
}

if (!function_exists('smarty_gtm_enqueue_front_scripts')) {
    /**
     * Enqueue necessary JavaScript for dataLayer
     *
     * @return void
     */
    function smarty_gtm_enqueue_front_scripts() {
        // Enqueue on WooCommerce pages, cart page, and checkout page
        if (is_woocommerce() || is_cart() || is_checkout()) {
            // Register the script
            wp_register_script('smarty-gtm-script', plugins_url('js/smarty-gtm-events.js', __FILE__), array('jquery'),'1.0.0', true);

            // Enqueue the script
            wp_enqueue_script('smarty-gtm-script');

            // Generate a nonce and pass it to JavaScript
            wp_localize_script('smarty-gtm-script', 'smartyGtmEvents', array(
                'ajaxUrl'  => admin_url('admin-ajax.php'),
                'nonce'    => smarty_gtm_get_nonce(),
            ));
        }
    }
    add_action('wp_enqueue_scripts', 'smarty_gtm_enqueue_front_scripts');
}

if (!function_exists('smarty_gtm_get_site_identifier')) {
    /**
     * Get the unique site identifier (URL or name)
     *
     * @return array Associative array containing 'siteUrl' and 'siteName'
     */
    function smarty_gtm_get_site_identifier() {
        return array(
            'siteUrl'  => get_site_url(),
            'siteName' => get_bloginfo('name'),
        );
    }
}

if (!function_exists('smarty_gtm_push_to_dataLayer')) {
    /**
     * Utility function to push data to the dataLayer
     *
     * @param array $data Data to push to dataLayer
     * @return void
     */
    function smarty_gtm_push_to_dataLayer($data) {
        echo "\n<!-- SM - GTM Events for WooCommerce Plugin: Start Data Layer Event -->\n";
        echo '<script type="text/javascript">';
        echo 'window.dataLayer = window.dataLayer || []; window.dataLayer.push(' . wp_json_encode($data) . ');';
        echo '</script>';
        echo "\n<!-- SM - GTM Events for WooCommerce Plugin: End Data Layer Event -->\n";
    }
}

if (!function_exists('smarty_gtm_format_event_model')) {
    /**
     * Format event model for GTM data layer
     *
     * @param string $event Event name
     * @param string $transaction_id Transaction ID
     * @param float $value Transaction value
     * @param string $currency Currency code
     * @param float $shipping Shipping cost
     * @param float $tax Tax amount
     * @param array $items Array of items
     * @param string $event_source Event source identifier
     * @return array Formatted event model
     */
    function smarty_gtm_format_event_model($event, $transaction_id = '', $value = '', $currency = '', $shipping = '', $tax = '', $items = array(), $event_source = 'plugin') {
        $site_info = smarty_gtm_get_site_identifier();
        
        $customer_data = array();
        if (is_user_logged_in()) {
            $user = wp_get_current_user();
            $customer_data['user_id'] = $user->ID;
            $customer_data['user_role'] = implode(', ', $user->roles);
        }

        return array(
            'event'      => $event,
            'eventModel' => array(
                'transaction_id' => $transaction_id,
                'affiliation'    => $site_info['siteUrl'],
                'value'          => $value,
                'currency'       => $currency,
                'shipping'       => $shipping,
                'tax'            => $tax,
                'items'          => $items,
                'event_source'   => $event_source,
            ),
            'customer' => $customer_data,
        );
    }
}

if (!function_exists('smarty_gtm_format_product_item')) {
    /**
     * Format product item data
     *
     * @param WC_Product $product WooCommerce product object
     * @param int $quantity Quantity of the product
     * @param int $list_position Position in the list
     * @return array Formatted product item data
     */
    function smarty_gtm_format_product_item($product, $quantity = 1, $list_position = 1) {
        // Get product categories
        $categories = wp_get_post_terms($product->get_id(), 'product_cat', array('fields' => 'names'));
        $category   = !empty($categories) ? implode('/', $categories) : '';

        // Get product brand if available (assuming it's stored as a custom attribute 'brand')
        $brand = $product->get_attribute('brand');

        // Get product variant if available (for variable products)
        $variant = '';
        if ($product->is_type('variation')) {
            $attributes = $product->get_variation_attributes();
            $variant    = implode(', ', $attributes);
        }

        return array(
            'id'            => $product->get_id(),
            'name'          => $product->get_name(),
            'list_name'     => 'Order',
            'brand'         => $brand ?: '',
            'category'      => $category,
            'variant'       => $variant,
            'list_position' => (string) $list_position,
            'price'         => (float) $product->get_price(),
            'quantity'      => (int) $quantity,
            'SKU'           => $product->get_sku() ?: '',
            'dimensions'    => array(
                'length' => $product->get_length() ?: '',
                'width'  => $product->get_width() ?: '',
                'height' => $product->get_height() ?: '',
            ),
            'weight'        => $product->get_weight(),
            'custom_fields' => get_post_meta( $product->get_id() ),
        );
    }
}

if (!function_exists('smarty_gtm_view_item')) {
    /**
     * Push view_item event on single product pages
     *
     * @return void
     */
    function smarty_gtm_view_item() {
        if (is_product()) {
            global $product;
            $data = smarty_gtm_format_event_model(
                'view_item',
                '',
                (float) $product->get_price(),
                get_woocommerce_currency(),
                '',
                '',
                array( smarty_gtm_format_product_item($product)),
                'smarty-gtm-events-for-woocommerce'
            );

            smarty_gtm_push_to_dataLayer($data);

            smarty_gtm_log_event('view_item', $data);
        }
    }
    add_action('woocommerce_after_single_product', 'smarty_gtm_view_item');
}

if (!function_exists('smarty_gtm_view_item_list')) {
    /**
     * Push view_item_list event on product list pages
     *
     * @return void
     */
    function smarty_gtm_view_item_list() {
        if (is_shop() || is_product_category() || is_product_tag()) {
            global $wp_query;
            $products = get_transient('smarty_gtm_product_list');

            if (false === $products) {
                $products = array();
                foreach ($wp_query->posts as $index => $post) {
                    $product = wc_get_product($post->ID);
                    if ($product) {
                        $products[] = smarty_gtm_format_product_item($product, 1, $index + 1);
                    }
                }
                // Cache the products data for 10 minutes
                set_transient('smarty_gtm_product_list', $products, 10 * MINUTE_IN_SECONDS);
            }

            $data = smarty_gtm_format_event_model(
                'view_item_list',
                '',
                '',
                get_woocommerce_currency(),
                '',
                '',
                $products,
                'smarty-gtm-events-for-woocommerce'
            );

            smarty_gtm_push_to_dataLayer($data);

            smarty_gtm_log_event('view_item_list', $data);
        }
    }
    add_action('woocommerce_after_shop_loop', 'smarty_gtm_view_item_list');
}

if (!function_exists('smarty_gtm_clear_product_list_cache')) {
    /**
     * Clear product list cache when a product is updated
     *
     * @param int $post_id Post ID
     * @return void
     */
    function smarty_gtm_clear_product_list_cache($post_id) {
        if (get_post_type($post_id) == 'product') {
            delete_transient('smarty_gtm_product_list');
        }
    }
    add_action('save_post', 'smarty_gtm_clear_product_list_cache');
}

if (!function_exists('smarty_gtm_add_to_cart_ajax')) {
    /**
     * Push add_to_cart event when product is added to cart via AJAX
     *
     * @return void
     */
    function smarty_gtm_add_to_cart_ajax() {
        check_ajax_referer('smarty_gtm_events_nonce', 'nonce');

        $product_id = isset($_POST['product_id']) ? absint($_POST['product_id']) : 0;
        $quantity   = isset($_POST['quantity']) ? intval($_POST['quantity']) : 1;

        if ($product_id <= 0) {
            smarty_gtm_log_error($error_message);
            wp_send_json_error(array('error' => __('Product ID is missing or invalid', 'smarty-gtm-events-for-woocommerce')));
            return;
        }

        $product = wc_get_product($product_id);
        if (!$product) {
            smarty_gtm_log_error($error_message);
            wp_send_json_error(array('error' => __('Product not found', 'smarty-gtm-events-for-woocommerce')));
            return;
        }

        $data = smarty_gtm_format_event_model(
            'add_to_cart',
            '',
            (float) $product->get_price() * $quantity,
            get_woocommerce_currency(),
            '',
            '',
            array( smarty_gtm_format_product_item($product, $quantity) ),
            'smarty-gtm-events-for-woocommerce'
        );

        smarty_gtm_log_event('add_to_cart', $data);

        wp_send_json_success($data);
    }
    add_action('wp_ajax_smarty_gtm_add_to_cart', 'smarty_gtm_add_to_cart_ajax');
    add_action('wp_ajax_nopriv_smarty_gtm_add_to_cart', 'smarty_gtm_add_to_cart_ajax');
}

if (!function_exists('smarty_gtm_view_cart')) {
    /**
     * Push view_cart event when cart page is viewed
     *
     * @return void
     */
    function smarty_gtm_view_cart() {
        if (is_cart()) {
            $cart_items = array();
            $index      = 0;
            foreach (WC()->cart->get_cart() as $cart_item) {
                $product = $cart_item['data'];
                $index++;
                $cart_items[] = smarty_gtm_format_product_item($product, $cart_item['quantity'], $index);
            }

            $data = smarty_gtm_format_event_model(
                'view_cart',
                '',
                WC()->cart->get_cart_contents_total(),
                get_woocommerce_currency(),
                WC()->cart->get_shipping_total(),
                WC()->cart->get_total_tax(),
                $cart_items,
                'smarty-gtm-events-for-woocommerce'
            );

            smarty_gtm_push_to_dataLayer($data);

            smarty_gtm_log_event('view_cart', $data);
        }
    }
    add_action('woocommerce_after_cart_table', 'smarty_gtm_view_cart');
}

if (!function_exists('smarty_gtm_remove_from_cart')) {
    /**
     * Push remove_from_cart event when a product is removed from cart
     *
     * @param string   $cart_item_key Key of the cart item being removed
     * @param WC_Cart  $cart          The cart object
     * @return void
     */
    function smarty_gtm_remove_from_cart($cart_item_key, $cart) {
        $cart_item = $cart->get_cart_item($cart_item_key);
        $product = $cart_item['data'];

        $data = smarty_gtm_format_event_model(
            'remove_from_cart',
            '',
            $product->get_price() * $cart_item['quantity'],
            get_woocommerce_currency(),
            '',
            '',
            [smarty_gtm_format_product_item($product, $cart_item['quantity'])],
            'smarty-gtm-events-for-woocommerce'
        );

        add_action('wp_footer', function() use ($data) {
            smarty_gtm_push_to_dataLayer($data);
        });

        smarty_gtm_log_event('remove_from_cart', $data);
    }
    add_action('woocommerce_remove_cart_item', 'smarty_gtm_remove_from_cart', 10, 2);
}

if (!function_exists('smarty_gtm_add_data_to_remove_link')) {
    /**
     * Add data-product_id attribute to cart item remove links
     *
     * @param string $url The original remove link HTML
     * @param string $cart_item_key The cart item key
     * @return string Modified remove link HTML
     */
    function smarty_gtm_add_data_to_remove_link($url, $cart_item_key) {
        $cart_item = WC()->cart->get_cart_item($cart_item_key);
        if ($cart_item && isset($cart_item['product_id'])) {
            $product_id = $cart_item['product_id'];
            // Add data-product_id attribute
            $url = str_replace('<a ', '<a data-product_id="' . $product_id . '" ', $url);
        }
        return $url;
    }
    add_filter('woocommerce_cart_item_remove_link', 'smarty_gtm_add_data_to_remove_link', 10, 2);
}

if (!function_exists('smarty_gtm_get_product_data')) {
    /**
     * AJAX handler to get product data for remove_from_cart event
     */
    function smarty_gtm_get_product_data() {
        check_ajax_referer('smarty_gtm_events_nonce', 'nonce');

        $product_id = isset($_POST['product_id']) ? absint($_POST['product_id']) : 0;

        if ($product_id <= 0) {
            smarty_gtm_log_error($error_message);
            wp_send_json_error(array('error' => __('Product ID is missing or invalid', 'smarty-gtm-events-for-woocommerce')));
            return;
        }

        $product = wc_get_product($product_id);
        if (!$product) {
            smarty_gtm_log_error($error_message);
            wp_send_json_error(array('error' => __('Product not found', 'smarty-gtm-events-for-woocommerce')));
            return;
        }

        // Since we don't have quantity info, assume 1
        $product_data = smarty_gtm_format_product_item($product, 1);

        wp_send_json_success($product_data);
    }
    add_action('wp_ajax_nopriv_smarty_gtm_get_product_data', 'smarty_gtm_get_product_data');
    add_action('wp_ajax_smarty_gtm_get_product_data', 'smarty_gtm_get_product_data');
}

if (!function_exists('smarty_gtm_begin_checkout')) {
    /**
     * Push begin_checkout event when checkout is started
     *
     * @return void
     */
    function smarty_gtm_begin_checkout() {
        if (is_checkout() && ! is_order_received_page()) {
            $cart_items = array();
            $cart_total = 0.0;

            $index = 0;
            foreach (WC()->cart->get_cart() as $cart_item) {
                $product   = $cart_item['data'];
                $quantity  = (int) $cart_item['quantity'];
                $price     = (float) $product->get_price();
                $cart_total += $price * $quantity;
                $index++;
                $cart_items[] = smarty_gtm_format_product_item($product, $quantity, $index);
            }

            $data = smarty_gtm_format_event_model(
                'begin_checkout',
                uniqid('order_'),
                number_format($cart_total, 2, '.', ''),
                get_woocommerce_currency(),
                number_format((float) WC()->cart->get_shipping_total(), 2, '.', ''),
                number_format((float) WC()->cart->get_total_tax(), 2, '.', ''),
                $cart_items,
                'smarty-gtm-events-for-woocommerce'
            );

            smarty_gtm_push_to_dataLayer($data);

            smarty_gtm_log_event('begin_checkout', $data);
        }
    }
    add_action('woocommerce_before_checkout_form', 'smarty_gtm_begin_checkout');
}

if (!function_exists('smarty_gtm_purchase')) {
    /**
     * Push purchase event on order confirmation page
     *
     * @param int $order_id Order ID
     * @return void
     */
    function smarty_gtm_purchase($order_id) {
        $order = wc_get_order($order_id);
        if (!$order) {
            return;
        }

        $items = array();
        $index = 0;
        foreach ($order->get_items() as $item) {
            $product = $item->get_product();
            if ($product) {
                $index++;
                $items[] = smarty_gtm_format_product_item($product, $item->get_quantity(), $index);
            }
        }

        $data = smarty_gtm_format_event_model(
            'purchase',
            $order->get_order_number(),
            (float) $order->get_total(),
            $order->get_currency(),
            (float) $order->get_shipping_total(),
            (float) $order->get_total_tax(),
            $items,
            'smarty-gtm-events-for-woocommerce'
        );

        smarty_gtm_push_to_dataLayer($data);

        smarty_gtm_log_event('purchase', $data);
    }
    add_action('woocommerce_thankyou', 'smarty_gtm_purchase', 10, 1);
}

if (!function_exists('smarty_gtm_add_payment_info')) {
    /**
     * Push add_payment_info event to dataLayer when payment information is submitted in the checkout process
     *
     * @param array $posted_data Posted data from checkout form
     * @param WP_Error $errors Validation errors
     * @return void
     */
    function smarty_gtm_add_payment_info() {
        if (is_checkout() && !is_order_received_page()) {
            // Prepare cart items data
            $cart_items = [];
            $cart_total = 0;

            foreach (WC()->cart->get_cart() as $index => $cart_item) {
                $product = $cart_item['data'];
                $quantity = intval($cart_item['quantity']);
                $price = floatval($product->get_price());

                $line_total = $price * $quantity;
                $cart_total += $line_total;

                $cart_items[] = [
                    'id' => $product->get_id(),
                    'name' => $product->get_name(),
                    'price' => $price,
                    'quantity' => $quantity,
                ];
            }

            $payment_method = WC()->session->get('chosen_payment_method') ?: 'unknown';
            
            $data = smarty_gtm_format_event_model(
                'add_payment_info',
                uniqid('order_'),
                $cart_total,
                get_woocommerce_currency(),
                number_format((float) WC()->cart->get_shipping_total(), 2, '.', ''),
                number_format((float) WC()->cart->get_total_tax(), 2, '.', ''),
                $cart_items,
                'smarty-gtm-events-for-woocommerce'
            );

            // Add additional field for payment type
            $data['eventModel']['payment_type'] = $payment_method;

            // Push the formatted data to the dataLayer
            smarty_gtm_push_to_dataLayer($data);

            smarty_gtm_log_event('add_payment_info', $data);
        }
    }
    add_action('woocommerce_review_order_after_payment', 'smarty_gtm_add_payment_info');
}

if (!function_exists('smarty_gtm_add_shipping_info')) {
    /**
     * Push add_shipping_info event to the dataLayer when shipping information is submitted.
     *
     * @return void
     */
    function smarty_gtm_add_shipping_info() {
        if (is_checkout() && !is_order_received_page()) {
            // Prepare cart items data
            $cart_items = [];
            $cart_total = 0;

            foreach (WC()->cart->get_cart() as $index => $cart_item) {
                $product = $cart_item['data'];
                $quantity = intval($cart_item['quantity']);
                $price = floatval($product->get_price());

                $line_total = $price * $quantity;
                $cart_total += $line_total;

                $cart_items[] = [
                    'id' => $product->get_id(),
                    'name' => $product->get_name(),
                    'price' => $price,
                    'quantity' => $quantity,
                ];
            }

            // Get selected shipping method
            $shipping_method = isset(WC()->session->get('chosen_shipping_methods')[0]) ? WC()->session->get('chosen_shipping_methods')[0] : 'unknown';

            // Prepare the data
            $data = smarty_gtm_format_event_model(
                'add_shipping_info',
                uniqid('order_'),
                $cart_total,
                get_woocommerce_currency(),
                number_format((float) WC()->cart->get_shipping_total(), 2, '.', ''),
                number_format((float) WC()->cart->get_total_tax(), 2, '.', ''),
                $cart_items,
                'smarty-gtm-events-for-woocommerce'
            );

            // Add the shipping method to the event model
            $data['eventModel']['shipping_method'] = $shipping_method;

            // Push the event to the dataLayer
            smarty_gtm_push_to_dataLayer($data);

            // Log the event
            smarty_gtm_log_event('add_shipping_info', $data);
        }
    }
    add_action('woocommerce_review_order_after_shipping', 'smarty_gtm_add_shipping_info');
}

if (!function_exists('smarty_gtm_site_search_tracking')) {
    /**
     * Push search event when a search is performed
     *
     * @return void
     */
    function smarty_gtm_site_search_tracking() {
        if (is_search()) {
            add_action('wp_footer', 'smarty_gtm_push_search_event');
        }
    }
    add_action('template_redirect', 'smarty_gtm_site_search_tracking');
}

if (!function_exists('smarty_gtm_push_search_event')) {
    /**
     * Outputs the search event script
     *
     * @return void
     */
    function smarty_gtm_push_search_event() {
        $search_query = get_search_query();
        $data = array(
            'event' => 'search',
            'search_term' => $search_query,
        );
        smarty_gtm_push_to_dataLayer($data);

        smarty_gtm_log_event('search', $data);
    }
}

if (!function_exists('smarty_gtm_coupon_applied')) {
    /**
     * Push apply_coupon event when a coupon is applied
     *
     * @param string $coupon_code Applied coupon code
     * @return void
     */
    function smarty_gtm_coupon_applied($coupon_code) {
        $data = array(
            'event' => 'apply_coupon',
            'coupon' => $coupon_code,
        );
        smarty_gtm_push_to_dataLayer($data);

        smarty_gtm_log_event('apply_coupon', $data);
    }
    add_action('woocommerce_applied_coupon', 'smarty_gtm_coupon_applied');
}

if (!function_exists('smarty_gtm_order_refunded')) {
    /**
     * Push refund event when an order is refunded
     *
     * @param int $order_id Order ID
     * @param int $refund_id Refund ID
     * @return void
     */
    function smarty_gtm_order_refunded($order_id, $refund_id) {
        $order = wc_get_order($order_id);
        $refund = wc_get_order($refund_id);

        $data = array(
            'event' => 'refund',
            'transaction_id' => $order->get_order_number(),
            'value' => (float) $refund->get_amount(),
            'currency' => $order->get_currency(),
        );
        smarty_gtm_push_to_dataLayer($data);

        smarty_gtm_log_event('refund', $data);
    }
    add_action('woocommerce_order_refunded', 'smarty_gtm_order_refunded', 10, 2);
}

if (!function_exists('smarty_gtm_create_event_log_table')) {
    /**
     * Create the event log database table upon plugin activation.
     *
     * @return void
     */
    function smarty_gtm_create_event_log_table() {
        global $wpdb;
        $table_name = $wpdb->prefix . 'smarty_gtm_event_log';

        $charset_collate = $wpdb->get_charset_collate();

        $sql = "CREATE TABLE IF NOT EXISTS $table_name (
            id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
            event_time DATETIME NOT NULL,
            event_name VARCHAR(255) NOT NULL,
            user_id BIGINT(20) UNSIGNED DEFAULT NULL,
            user_role VARCHAR(255) DEFAULT NULL,
            event_data LONGTEXT DEFAULT NULL,
            PRIMARY KEY (id),
            INDEX (event_time),
            INDEX (event_name)
        ) $charset_collate;";

        require_once(ABSPATH . 'wp-admin/includes/upgrade.php');
        dbDelta($sql);
    }
}

if (!function_exists('smarty_gtm_create_error_log_table')) {
    /**
     * Create the error log database table upon plugin activation.
     *
     * @return void
     */
    function smarty_gtm_create_error_log_table() {
        global $wpdb;
        $table_name = $wpdb->prefix . 'smarty_gtm_error_log';

        $charset_collate = $wpdb->get_charset_collate();

        $sql = "CREATE TABLE IF NOT EXISTS $table_name (
            id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
            error_time DATETIME NOT NULL,
            error_message TEXT NOT NULL,
            PRIMARY KEY (id),
            INDEX (error_time)
        ) $charset_collate;";

        require_once(ABSPATH . 'wp-admin/includes/upgrade.php');
        dbDelta($sql);
    }
}

if (!function_exists('smarty_gtm_plugin_activation')) {
    /**
     * Plugin activation hook to create necessary database tables.
     *
     * @return void
     */
    function smarty_gtm_plugin_activation() {
        smarty_gtm_create_event_log_table();
        smarty_gtm_create_error_log_table();
    }
    register_activation_hook(__FILE__, 'smarty_gtm_plugin_activation');
}

if (!function_exists('smarty_gtm_log_event')) {
    /**
     * Log an event to the database.
     *
     * @param string $event_name Event name.
     * @param array  $event_data Event data.
     * @return void
     */
    function smarty_gtm_log_event($event_name, $event_data = array()) {
        global $wpdb;
        $table_name = $wpdb->prefix . 'smarty_gtm_event_log';

        $user_id = null;
        $user_role = null;
        if (is_user_logged_in()) {
            $user = wp_get_current_user();
            $user_id = $user->ID;
            $user_role = implode(', ', $user->roles);
        }

        $wpdb->insert(
            $table_name,
            array(
                'event_time' => current_time('mysql'),
                'event_name' => $event_name,
                'user_id' => $user_id,
                'user_role' => $user_role,
                'event_data' => maybe_serialize($event_data),
            ),
            array(
                '%s',
                '%s',
                '%d',
                '%s',
                '%s',
            )
        );
    }
}

/**
 * Log an error message and reset the dismissed flag.
 *
 * @param string $error_message Error message to log.
 * @return void
 */
function smarty_gtm_log_error($error_message) {
    global $wpdb;
    $table_name = $wpdb->prefix . 'smarty_gtm_error_log';

    $wpdb->insert(
        $table_name,
        array(
            'error_time' => current_time('mysql'),
            'error_message' => $error_message,
        ),
        array(
            '%s',
            '%s',
        )
    );

    // Reset the dismissed flag when a new error is logged
    delete_option('smarty_gtm_errors_dismissed');
}

/**
 * Retrieve recent errors from the error log.
 *
 * @param int $limit Number of errors to retrieve.
 * @return array Array of recent errors.
 */
function smarty_gtm_get_recent_errors($limit = 5) {
    global $wpdb;
    $table_name = $wpdb->prefix . 'smarty_gtm_error_log';

    $results = $wpdb->get_results(
        $wpdb->prepare("SELECT error_time, error_message FROM $table_name ORDER BY error_time DESC LIMIT %d", $limit),
        ARRAY_A
    );

    return $results;
}

/**
 * Display an admin notice if there are logged errors or a simulated error.
 *
 * @return void
 */
function smarty_gtm_display_error_notice() {
    // Only show the notice to users who can manage options
    if (!current_user_can('manage_options')) {
        return;
    }

    // Check if the notice has been dismissed
    $dismissed = get_option('smarty_gtm_errors_dismissed');
    if ($dismissed) {
        return;
    }

    // Check for a simulated error
    if (get_option('smarty_gtm_simulated_error_notice')) {
        echo '<div class="notice notice-success is-dismissible">';
        echo '<p><strong>SM - GTM Events for WooCommerce:</strong> Simulated error has been logged.</p>';
        echo '</div>';

        // Remove the notice after displaying it once
        delete_option('smarty_gtm_simulated_error_notice');
    }

    // Get recent errors
    $errors = smarty_gtm_get_recent_errors();

    if (!empty($errors)) {
        // Prepare the error messages
        $error_messages = '';
        foreach ($errors as $error) {
            $error_messages .= '<li>' . esc_html($error['error_time']) . ' - ' . esc_html($error['error_message']) . '</li>';
        }

        // Display the admin notice
        echo '<div class="notice notice-error is-dismissible">';
        echo '<p><strong>SM - GTM Events for WooCommerce:</strong> The following errors have been logged.</p>';
        echo '<ul>' . $error_messages . '</ul>';
        echo '<p>Please check the plugin settings or contact support for assistance.</p>';
        echo '</div>';

        // Include a script to handle the dismiss action
        ?>
        <script type="text/javascript">
            jQuery(document).on('click', '.notice-error.is-dismissible .notice-dismiss', function () {
                jQuery.ajax({
                    url: ajaxurl,
                    method: 'POST',
                    data: {
                        action: 'smarty_gtm_dismiss_errors',
                        nonce: '<?php echo wp_create_nonce('smarty_gtm_dismiss_errors_nonce'); ?>'
                    }
                });
            });
        </script>
        <?php
    }
}
add_action('admin_notices', 'smarty_gtm_display_error_notice');

/**
 * Handle the AJAX request to dismiss the error notice.
 *
 * @return void
 */
function smarty_gtm_dismiss_errors() {
    // Verify nonce
    check_ajax_referer('smarty_gtm_dismiss_errors_nonce', 'nonce');

    // Check if the user has the capability to manage options
    if (!current_user_can('manage_options')) {
        wp_send_json_error('Unauthorized', 403);
    }

    // Update the option to indicate that errors have been dismissed
    update_option('smarty_gtm_errors_dismissed', true);

    wp_send_json_success();
}
add_action('wp_ajax_smarty_gtm_dismiss_errors', 'smarty_gtm_dismiss_errors');

/**
 * Log an error when a specific URL parameter is present.
 *
 * Usage: Visit https://your-site.com/wp-admin/?simulate_error=1 to trigger.
 *
 * @return void
 */
function smarty_gtm_log_error_on_demand() {
    if (isset($_GET['simulate_error'])) {
        $error_message = 'Simulated error triggered via URL parameter.';
        smarty_gtm_log_error($error_message);

        // Set a temporary notice flag
        update_option('smarty_gtm_simulated_error_notice', true);

        // Redirect back to the settings page
        wp_safe_redirect(admin_url('admin.php?page=smarty-gtm-settings'));
        exit;
    }
}
add_action('admin_init', 'smarty_gtm_log_error_on_demand');

/**
 * Clear the GTM event and error logs when a specific URL parameter is present.
 *
 * Usage: Visit https://your-site.com/wp-admin/?clear_gtm_logs=1&key=your-unique-secret-key to trigger.
 *
 * @return void
 */
function smarty_gtm_clear_logs_on_demand() {
    if (isset($_GET['clear_gtm_logs']) && isset($_GET['key'])) {
        if (!is_user_logged_in() || !current_user_can('manage_options')) {
            wp_die(__('You are not authorized to perform this action.', 'smarty-gtm-events-for-woocommerce'));
        }

        // Verify the secret key
        if ($_GET['key'] !== SMARTY_GTM_CLEAR_LOGS_SECRET) {
            wp_die(__('Invalid key provided.', 'smarty-gtm-events-for-woocommerce'));
        }

        // Proceed to clear the logs
        smarty_gtm_clear_event_logs();
        smarty_gtm_clear_error_logs();

        // Set a flag to indicate that logs have been cleared
        update_option('smarty_gtm_logs_cleared', true);
    }
}
add_action('admin_init', 'smarty_gtm_clear_logs_on_demand');

/**
 * Display an admin notice when the logs have been cleared.
 *
 * @return void
 */
function smarty_gtm_display_clear_logs_notice() {
    // Check if the logs have been cleared
    if (get_option('smarty_gtm_logs_cleared')) {
        echo '<div class="notice notice-success is-dismissible">';
        echo '<p>' . __('SM - GTM Events for WooCommerce: Event and error logs have been cleared.', 'smarty-gtm-events-for-woocommerce') . '</p>';
        echo '</div>';

        // Delete the flag to prevent the notice from showing again
        delete_option('smarty_gtm_logs_cleared');
    }
}
add_action('admin_notices', 'smarty_gtm_display_clear_logs_notice');

/**
 * Clear event logs.
 */
function smarty_gtm_clear_event_logs() {
    global $wpdb;
    $table_name = $wpdb->prefix . 'smarty_gtm_event_log';
    $wpdb->query("TRUNCATE TABLE $table_name");
}

/**
 * Clear error logs.
 */
function smarty_gtm_clear_error_logs() {
    global $wpdb;
    $table_name = $wpdb->prefix . 'smarty_gtm_error_log';
    $wpdb->query("TRUNCATE TABLE $table_name");
}

/**
 * ADD A SETTINGS PAGE UNDER 'SETTINGS' -> 'GTM Events for WooCommerce'
 * This page displays the debug.log contents.
 */
if (!function_exists('smarty_gtm_menu')) {
    /**
     * Register the custom settings page under 'Settings'.
     */
    function smarty_gtm_menu() {
        add_submenu_page(
            'woocommerce',
            __('GTM Events | Settings', 'smarty-gtm-events-for-woocommerce'),
            __('GTM Events', 'smarty-gtm-events-for-woocommerce'),
            'manage_options',
            'smarty-gtm-settings',
            'smarty_gtm_settings_page'
        );
    }
    add_action('admin_menu', 'smarty_gtm_menu');
}

if (!function_exists('smarty_gtm_register_settings')) {
    /**
     * Register plugin settings.
     */
    function smarty_gtm_register_settings() {
        add_settings_section(
            'smarty_gtm_section_general',
            __('General', 'smarty-gtm-events-for-woocommerce'),
            'smarty_gtm_section_general_callback',
            'smarty-gtm-settings'
        );
    }
    add_action('admin_init', 'smarty_gtm_register_settings');
}

if (!function_exists('smarty_gtm_section_general_callback')) {
    /**
     * Display the description for the general settings section.
     *
     * This function outputs the description text for the "General" section
     * in the plugin's settings page.
     *
     * @return void
     */
    function smarty_gtm_section_general_callback() {
        echo '<p>' . esc_html__('Below is the plugin events and error logs. No other settings are currently available.', 'smarty-auto-approve-reviews') . '</p>';
    }
}

if (!function_exists('smarty_gtm_settings_page')) {
    /**
     * Render the plugin settings page with a user-friendly log display.
     */
    function smarty_gtm_settings_page() {
        if (!current_user_can('manage_options')) {
            wp_die(__('You do not have sufficient permissions to access this page.', 'smarty-auto-approve-reviews'));
        }

        // We no longer fetch event logs here (we’ll fetch them via AJAX pagination).
        // But we still fetch the error logs normally:
        $error_logs = smarty_gtm_get_recent_errors(50);

        ?>
        <div class="wrap">
            <h1><?php esc_html_e('GTM Events | Settings', 'smarty-gtm-events-for-woocommerce'); ?></h1>
            <div id="smarty-gtm-settings-container">
                <div>
                    <form action="options.php" method="post">
                        <?php
                            settings_fields('smarty-gtm-settings');
                            do_settings_sections('smarty-gtm-settings');
                            //submit_button(__('Save Settings', 'smarty-gtm-events-for-woocommerce'));
                        ?>
                    </form>

                    <!-- Event Logs Section (Now loaded via AJAX) -->
                    <h2><?php esc_html_e('Event Logs', 'smarty-gtm-events-for-woocommerce'); ?></h2>
                    <p><?php esc_html_e('Below are the most recent events logged by the plugin:', 'smarty-gtm-events-for-woocommerce'); ?></p>
                    
                    <div id="smarty-gtm-event-logs-table-container">
                        <p><?php esc_html_e('Loading event logs...', 'smarty-gtm-events-for-woocommerce'); ?></p>
                    </div>
                    
                    <!-- Simple pagination controls (initially hidden by `display: none`) -->
                    <div id="smarty-gtm-event-logs-pagination" style="margin-top: 15px; display: none;">
                        <button id="smarty-gtm-prev-page" class="button">
                            <?php esc_html_e('Prev', 'smarty-gtm-events-for-woocommerce'); ?>
                        </button>
                        <span style="position: relative; margin: 0 15px; top: 5px;">
                            <?php esc_html_e('Page', 'smarty-gtm-events-for-woocommerce'); ?>
                            <span id="smarty-gtm-current-page">1</span>
                            <?php esc_html_e('of', 'smarty-gtm-events-for-woocommerce'); ?>
                            <span id="smarty-gtm-total-pages">1</span>
                        </span>
                        <button id="smarty-gtm-next-page" class="button">
                            <?php esc_html_e('Next', 'smarty-gtm-events-for-woocommerce'); ?>
                        </button>
                    </div>

                    <!-- Delete Events  Section -->
                    <form id="smarty-gtm-clear-old-events-form" class="smarty-gtm-delete-events-form">
                        <label for="smarty-gtm-delete-older-than" class="smarty-gtm-delete-events-label">
                            <?php esc_html_e('Delete events older than:', 'smarty-gtm-events-for-woocommerce'); ?>
                        </label>
                        <select id="smarty-gtm-delete-older-than" class="smarty-gtm-delete-events-select" name="smarty-gtm-delete-older-than">
                            <option value="7">7 <?php esc_html_e('days', 'smarty-gtm-events-for-woocommerce'); ?></option>
                            <option value="30">30 <?php esc_html_e('days', 'smarty-gtm-events-for-woocommerce'); ?></option>
                            <option value="90">90 <?php esc_html_e('days', 'smarty-gtm-events-for-woocommerce'); ?></option>
                            <option value="365">1 <?php esc_html_e('year', 'smarty-gtm-events-for-woocommerce'); ?></option>
                        </select>
                        <button type="button" class="button button-secondary" id="smarty-gtm-delete-old-events">
                            <?php esc_html_e('Delete', 'smarty-gtm-events-for-woocommerce'); ?>
                        </button>
                    </form>

                    <!-- Error Logs Section (unchanged for now) -->
                    <h2><?php esc_html_e('Error Logs', 'smarty-gtm-events-for-woocommerce'); ?></h2>
                    <p><?php esc_html_e('Below are the most recent errors logged by the plugin:', 'smarty-gtm-events-for-woocommerce'); ?></p>
                    <div id="smarty-gtm-error-logs-table-container">
                        <table class="widefat fixed" style="margin-bottom: 20px;">
                            <thead>
                                <tr>
                                    <th style="width: 30%;"><?php esc_html_e('Error Time', 'smarty-gtm-events-for-woocommerce'); ?></th>
                                    <th style="width: 70%;"><?php esc_html_e('Error Message', 'smarty-gtm-events-for-woocommerce'); ?></th>
                                </tr>
                            </thead>
                            <tbody>
                                <?php if (!empty($error_logs)) : ?>
                                    <?php foreach ($error_logs as $error) : ?>
                                        <tr>
                                            <td><?php echo esc_html($error['error_time']); ?></td>
                                            <td><?php echo esc_html($error['error_message']); ?></td>
                                        </tr>
                                    <?php endforeach; ?>
                                <?php else : ?>
                                    <tr>
                                        <td colspan="2">
                                            <?php esc_html_e('No errors logged yet.', 'smarty-gtm-events-for-woocommerce'); ?>
                                        </td>
                                    </tr>
                                <?php endif; ?>
                            </tbody>
                        </table>
                    </div>

                    <!-- Buttons for Managing Error Logs -->
                    <div style="margin-top: 30px;">
                        <button type="button" class="button button-danger" id="smarty-gtm-delete-error-logs">
                            <?php esc_html_e('Delete', 'smarty-gtm-events-for-woocommerce'); ?>
                        </button>
                        <a href="?simulate_error=1" class="button button-primary">
                            <?php esc_html_e('Simulate Error', 'smarty-gtm-events-for-woocommerce'); ?>
                        </a>
                    </div>
                </div>

                <!-- The Tabs Container (Documentation & Changelog) -->
                <div id="smarty-gtm-tabs-container">
                    <div>
                        <h2 class="smarty-gtm-nav-tab-wrapper">
                            <a href="#smarty-gtm-documentation" class="smarty-gtm-nav-tab smarty-gtm-nav-tab-active">
                                <?php esc_html_e('Documentation', 'smarty-gtm-events-for-woocommerce'); ?>
                            </a>
                            <a href="#smarty-gtm-changelog" class="smarty-gtm-nav-tab">
                                <?php esc_html_e('Changelog', 'smarty-gtm-events-for-woocommerce'); ?>
                            </a>
                        </h2>
                        <div id="smarty-gtm-documentation" class="smarty-gtm-tab-content active">
                            <div class="smarty-gtm-view-more-container">
                                <p><?php esc_html_e('Click "View More" to load the plugin documentation.', 'smarty-gtm-events-for-woocommerce'); ?></p>
                                <button id="smarty-gtm-load-readme-btn" class="button button-primary">
                                    <?php esc_html_e('View More', 'smarty-gtm-events-for-woocommerce'); ?>
                                </button>
                            </div>
                            <div id="smarty-gtm-readme-content" style="margin-top: 20px;"></div>
                        </div>
                        <div id="smarty-gtm-changelog" class="smarty-gtm-tab-content">
                            <div class="smarty-gtm-view-more-container">
                                <p><?php esc_html_e('Click "View More" to load the plugin changelog.', 'smarty-gtm-events-for-woocommerce'); ?></p>
                                <button id="smarty-gtm-load-changelog-btn" class="button button-primary">
                                    <?php esc_html_e('View More', 'smarty-gtm-events-for-woocommerce'); ?>
                                </button>
                            </div>
                            <div id="smarty-gtm-changelog-content" style="margin-top: 20px;"></div>
                        </div>
                    </div>
                </div>
            </div>
        </div><?php
    }
}

if (!function_exists('smarty_gtm_get_event_logs_paginated')) {
    /**
     * Retrieve event logs from the database in a paginated fashion.
     *
     * @param int $page  Current page number.
     * @param int $limit How many items per page.
     *
     * @return array
     * @type array $logs  The retrieved log entries.
     * @type int   $total Total number of logs in the table.
     */
    function smarty_gtm_get_event_logs_paginated($page = 1, $limit = 10) {
        global $wpdb;
        $table_name = $wpdb->prefix . 'smarty_gtm_event_log';

        // Calculate offset based on current page and limit
        $offset = ($page - 1) * $limit;

        // Get the total number of logs
        $total = (int) $wpdb->get_var("SELECT COUNT(*) FROM {$table_name}");

        // Retrieve only the logs for the requested page using LIMIT and OFFSET
        $results = $wpdb->get_results(
            $wpdb->prepare(
                "SELECT event_time, event_name, event_data 
                FROM {$table_name} 
                ORDER BY event_time DESC
                LIMIT %d, %d",
                $offset,
                $limit
            ),
            ARRAY_A
        );

        return [
            'logs'  => $results,
            'total' => $total,
        ];
    }
}

if (!function_exists('smarty_gtm_delete_old_events')) {
    /**
     * Deletes old GTM event logs based on the selected number of days.
     *
     * This function is triggered via an AJAX request from the admin panel.
     * It checks for the necessary permissions and nonce security before deleting 
     * records older than the specified number of days from the database.
     *
     * @return void Outputs a JSON response with the number of deleted records or an error message.
     */
    function smarty_gtm_delete_old_events() {
        check_ajax_referer('smarty_gtm_events_nonce', 'nonce');

        if (!current_user_can('manage_options')) {
            wp_send_json_error(array('message' => __('Unauthorized access', 'smarty-gtm-events-for-woocommerce')));
        }

        $days = isset($_POST['days']) ? absint($_POST['days']) : 30;
        global $wpdb;
        $table_name = $wpdb->prefix . 'smarty_gtm_event_log';

        $deleted_count = $wpdb->query(
            $wpdb->prepare(
                "DELETE FROM $table_name WHERE event_time < DATE_SUB(NOW(), INTERVAL %d DAY)",
                $days
            )
        );

        if ($deleted_count === false) {
            wp_send_json_error(array('message' => __('Failed to delete events', 'smarty-gtm-events-for-woocommerce')));
        } else {
            wp_send_json_success(array('deleted_count' => $deleted_count));
        }
    }
    add_action('wp_ajax_smarty_gtm_delete_old_events', 'smarty_gtm_delete_old_events');
}

if (!function_exists('smarty_gtm_delete_error_logs')) {
    /**
     * Deletes all error logs from the database.
     *
     * This function is triggered via an AJAX request from the admin panel.
     * It ensures proper security checks before deleting all error log entries.
     *
     * @return void Outputs a JSON response indicating success or failure.
     */
    function smarty_gtm_delete_error_logs() {
        check_ajax_referer('smarty_gtm_events_nonce', 'nonce');

        if (!current_user_can('manage_options')) {
            wp_send_json_error(array('message' => __('Unauthorized access', 'smarty-gtm-events-for-woocommerce')));
        }

        global $wpdb;
        $table_name = $wpdb->prefix . 'smarty_gtm_error_log';

        $wpdb->query("TRUNCATE TABLE $table_name");

        wp_send_json_success();
    }
    add_action('wp_ajax_smarty_gtm_delete_error_logs', 'smarty_gtm_delete_error_logs');
}

if (!function_exists('smarty_gtm_load_event_logs_paginated')) {
    /**
     * AJAX handler to return event logs for a given page in JSON format.
     */
    function smarty_gtm_load_event_logs_paginated() {
        check_ajax_referer('smarty_gtm_events_nonce', 'nonce');

        if (!current_user_can('manage_options')) {
            wp_send_json_error(__('You do not have sufficient permissions.', 'smarty-gtm-events-for-woocommerce'));
        }

        $page  = isset($_POST['page']) ? absint($_POST['page']) : 1;
        $limit = 10;

        // Retrieve rows
        $paginated_result = smarty_gtm_get_event_logs_paginated($page, $limit);
        $logs  = $paginated_result['logs'];
        $total = $paginated_result['total'];

        // For each row, unserialize and store as a JSON string
        foreach ($logs as &$row) {
            // Unserialize the event_data
            $raw_data = maybe_unserialize($row['event_data']);
            // Convert to pretty JSON (avoid HTML chars in output)
            $json_str = json_encode($raw_data, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);

            // Save back so the JS can display it directly
            $row['event_data'] = $json_str;
        }
        unset($row);

        // Now return the updated logs
        wp_send_json_success(array(
            'logs'  => $logs,
            'total' => $total,
        ));
    }
    add_action('wp_ajax_smarty_gtm_load_event_logs_paginated', 'smarty_gtm_load_event_logs_paginated');
    add_action('wp_ajax_nopriv_smarty_gtm_load_event_logs_paginated', 'smarty_gtm_load_event_logs_paginated');
}

if (!function_exists('smarty_gtm_load_readme')) {
    /**
     * AJAX handler to load and parse the README.md content.
     */
    function smarty_gtm_load_readme() {
        check_ajax_referer('smarty_gtm_events_nonce', 'nonce');
    
        if (!current_user_can('manage_options')) {
            wp_send_json_error('You do not have sufficient permissions.');
        }
    
        $readme_path = plugin_dir_path(__FILE__) . 'README.md';
        if (file_exists($readme_path)) {
            // Include Parsedown library
            if (!class_exists('Parsedown')) {
                require_once plugin_dir_path(__FILE__) . 'libs/Parsedown.php';
            }
    
            $parsedown = new Parsedown();
            $markdown_content = file_get_contents($readme_path);
            $html_content = $parsedown->text($markdown_content);
    
            // Remove <img> tags from the content
            $html_content = preg_replace('/<img[^>]*>/', '', $html_content);
    
            wp_send_json_success($html_content);
        } else {
            wp_send_json_error('README.md file not found.');
        }
    }    
    add_action('wp_ajax_smarty_gtm_load_readme', 'smarty_gtm_load_readme');
}

if (!function_exists('smarty_gtm_load_changelog')) {
    /**
     * AJAX handler to load and parse the CHANGELOG.md content.
     */
    function smarty_gtm_load_changelog() {
        check_ajax_referer('smarty_gtm_events_nonce', 'nonce');
    
        if (!current_user_can('manage_options')) {
            wp_send_json_error('You do not have sufficient permissions.');
        }
    
        $changelog_path = plugin_dir_path(__FILE__) . 'CHANGELOG.md';
        if (file_exists($changelog_path)) {
            if (!class_exists('Parsedown')) {
                require_once plugin_dir_path(__FILE__) . 'libs/Parsedown.php';
            }
    
            $parsedown = new Parsedown();
            $markdown_content = file_get_contents($changelog_path);
            $html_content = $parsedown->text($markdown_content);
    
            wp_send_json_success($html_content);
        } else {
            wp_send_json_error('CHANGELOG.md file not found.');
        }
    }
    add_action('wp_ajax_smarty_gtm_load_changelog', 'smarty_gtm_load_changelog');
}