add_shortcode('jj_show_product_meta', function($atts) {

    if ( ! current_user_can('manage_options') ) {
        return 'เฉพาะแอดมินเท่านั้น';
    }

    $atts = shortcode_atts([
        'id' => 0,
    ], $atts);

    $product_id = absint($atts['id']);

    if ( ! $product_id && is_product() ) {
        $product_id = get_the_ID();
    }

    if ( ! $product_id ) {
        return 'ไม่พบ Product ID';
    }

    $product = wc_get_product($product_id);

    if ( ! $product ) {
        return 'ไม่พบสินค้า';
    }

    ob_start();

    echo '<div style="background:#111;color:#fff;padding:20px;border-radius:8px;font-size:13px;line-height:1.6;overflow:auto;">';

    echo '<h2 style="color:#fff;">DEBUG PRODUCT META</h2>';
    echo '<p><strong>Product ID:</strong> ' . esc_html($product_id) . '</p>';
    echo '<p><strong>Product Type:</strong> ' . esc_html($product->get_type()) . '</p>';
    echo '<p><strong>Name:</strong> ' . esc_html($product->get_name()) . '</p>';
    echo '<p><strong>SKU:</strong> ' . esc_html($product->get_sku()) . '</p>';
    echo '<p><strong>Regular Price:</strong> ' . esc_html($product->get_regular_price()) . '</p>';
    echo '<p><strong>Sale Price:</strong> ' . esc_html($product->get_sale_price()) . '</p>';

    echo '<hr style="border-color:#555;">';

    echo '<h3 style="color:#fff;">ค่าที่ต้องเช็คเป็นพิเศษ</h3>';

    $check_keys = [
        '_notification_number',
        'notification_number',
        'single_notification_number',
        'nonumber',
        '_meta_vip_price',
        '_vip_price',
        'vip_price',
        'single_vip_price',
        '_meta_barcode',
        'barcode',
        '_sku',
        'w-w',
        'g_weight',
        'ctn_n',
        'ctn_size',
        'ctn_weight',
    ];

    echo '<table border="1" cellpadding="6" cellspacing="0" style="border-collapse:collapse;color:#fff;width:100%;">';
    echo '<tr><th align="left">Meta Key</th><th align="left">Value</th></tr>';

    foreach ( $check_keys as $key ) {
        $val = get_post_meta($product_id, $key, true);

        if ( is_array($val) || is_object($val) ) {
            $val = print_r($val, true);
        }

        echo '<tr>';
        echo '<td>' . esc_html($key) . '</td>';
        echo '<td><pre style="white-space:pre-wrap;color:#fff;margin:0;">' . esc_html($val) . '</pre></td>';
        echo '</tr>';
    }

    echo '</table>';

    echo '<hr style="border-color:#555;">';

    echo '<h3 style="color:#fff;">Meta ทั้งหมดของสินค้าแม่ / สินค้าเดี่ยว</h3>';

    $all_meta = get_post_meta($product_id);

    echo '<table border="1" cellpadding="6" cellspacing="0" style="border-collapse:collapse;color:#fff;width:100%;">';
    echo '<tr><th align="left">Meta Key</th><th align="left">Value</th></tr>';

    foreach ( $all_meta as $key => $values ) {
        $value = maybe_unserialize($values[0]);

        if ( is_array($value) || is_object($value) ) {
            $value = print_r($value, true);
        }

        echo '<tr>';
        echo '<td>' . esc_html($key) . '</td>';
        echo '<td><pre style="white-space:pre-wrap;color:#fff;margin:0;">' . esc_html($value) . '</pre></td>';
        echo '</tr>';
    }

    echo '</table>';

    if ( $product->is_type('variable') ) {

        echo '<hr style="border-color:#555;">';
        echo '<h3 style="color:#fff;">Variation ทั้งหมด</h3>';

        $variation_ids = $product->get_children();

        foreach ( $variation_ids as $variation_id ) {

            $variation = wc_get_product($variation_id);

            echo '<div style="border:1px solid #555;padding:12px;margin:12px 0;">';
            echo '<h4 style="color:#fff;">Variation ID: ' . esc_html($variation_id) . '</h4>';
            echo '<p><strong>SKU:</strong> ' . esc_html($variation ? $variation->get_sku() : '') . '</p>';
            echo '<p><strong>Regular Price:</strong> ' . esc_html($variation ? $variation->get_regular_price() : '') . '</p>';

            echo '<table border="1" cellpadding="6" cellspacing="0" style="border-collapse:collapse;color:#fff;width:100%;">';
            echo '<tr><th align="left">Meta Key</th><th align="left">Value</th></tr>';

            $variation_meta = get_post_meta($variation_id);

            foreach ( $variation_meta as $key => $values ) {
                $value = maybe_unserialize($values[0]);

                if ( is_array($value) || is_object($value) ) {
                    $value = print_r($value, true);
                }

                echo '<tr>';
                echo '<td>' . esc_html($key) . '</td>';
                echo '<td><pre style="white-space:pre-wrap;color:#fff;margin:0;">' . esc_html($value) . '</pre></td>';
                echo '</tr>';
            }

            echo '</table>';
            echo '</div>';
        }
    }

    echo '</div>';

    return ob_get_clean();
});