// AJAX handler for finding products by tire size with enhanced checks and fallback
add_action('wp_ajax_find_products_by_tire_size', 'find_products_by_tire_size');
add_action('wp_ajax_nopriv_find_products_by_tire_size', 'find_products_by_tire_size');
function find_products_by_tire_size() {
    verify_ajax_nonce();

    if (isset($_POST['tire_size'])) {
        $tire_size = sanitize_text_field($_POST['tire_size']);

        // Primary query with both taxonomy slugs
        $args = array(
            'post_type' => 'product',
            'posts_per_page' => -1,
            'tax_query' => array(
                'relation' => 'OR',
                array(
                    'taxonomy' => 'pa_tire_size',
                    'field' => 'name',
                    'terms' => $tire_size,
                ),
                array(
                    'taxonomy' => 'pa_tire-size',
                    'field' => 'name',
                    'terms' => $tire_size,
                ),
            ),
        );

        $query = new WP_Query($args);

        // Check if the query returned any products
        if ($query->have_posts()) {
            $html = '';
            while ($query->have_posts()) {
                $query->the_post();
                $html .= "<div class='product-item'>" . get_the_title() . "</div>";
            }
            wp_reset_postdata();
            wp_send_json_success($html);
        } else {
            // Logging and fallback for additional insights
            error_log("No products found for tire size: {$tire_size}. Attributes checked: pa_tire_size, pa_tire-size");

            // Fallback query without tax_query to see if any products load
            $fallback_args = array(
                'post_type' => 'product',
                'posts_per_page' => -1,
            );

            $fallback_query = new WP_Query($fallback_args);

            if ($fallback_query->have_posts()) {
                wp_send_json_error("Products exist, but none match the specified tire size taxonomy filter. Check the tire size taxonomy.");
            } else {
                wp_send_json_error("No products available at all, verify WooCommerce product data.");
            }

            wp_reset_postdata();
        }
    } else {
        wp_send_json_error("Tire size not provided.");
    }
}
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