<?php
/**
 * Admin Controller
 *
 * @package Jeremias\WcLicensedProduct\Admin
 */

declare(strict_types=1);

namespace Jeremias\WcLicensedProduct\Admin;

use Jeremias\WcLicensedProduct\License\License;
use Jeremias\WcLicensedProduct\License\LicenseManager;
use Twig\Environment;

/**
 * Handles admin pages for license management
 */
final class AdminController
{
    private Environment $twig;
    private LicenseManager $licenseManager;

    public function __construct(Environment $twig, LicenseManager $licenseManager)
    {
        $this->twig = $twig;
        $this->licenseManager = $licenseManager;
        $this->registerHooks();
    }

    /**
     * Register WordPress hooks
     */
    private function registerHooks(): void
    {
        // Add admin menu
        add_action('admin_menu', [$this, 'addAdminMenu']);

        // Enqueue admin styles
        add_action('admin_enqueue_scripts', [$this, 'enqueueStyles']);

        // Handle admin actions
        add_action('admin_init', [$this, 'handleAdminActions']);

        // Add licenses column to orders list
        add_filter('manage_edit-shop_order_columns', [$this, 'addOrdersLicenseColumn']);
        add_action('manage_shop_order_posts_custom_column', [$this, 'displayOrdersLicenseColumn'], 10, 2);

        // HPOS compatibility
        add_filter('woocommerce_shop_order_list_table_columns', [$this, 'addOrdersLicenseColumn']);
        add_action('woocommerce_shop_order_list_table_custom_column', [$this, 'displayOrdersLicenseColumnHpos'], 10, 2);

        // Add to WooCommerce Reports
        add_filter('woocommerce_admin_reports', [$this, 'addLicenseReports']);

        // AJAX handler for live search
        add_action('wp_ajax_wclp_live_search', [$this, 'handleLiveSearch']);
    }

    /**
     * Add admin menu pages
     */
    public function addAdminMenu(): void
    {
        add_submenu_page(
            'woocommerce',
            __('Licenses', 'wc-licensed-product'),
            __('Licenses', 'wc-licensed-product'),
            'manage_woocommerce',
            'wc-licenses',
            [$this, 'renderLicensesPage']
        );
    }

    /**
     * Add license reports to WooCommerce Reports
     */
    public function addLicenseReports(array $reports): array
    {
        $reports['licenses'] = [
            'title' => __('Licenses', 'wc-licensed-product'),
            'reports' => [
                'overview' => [
                    'title' => __('Overview', 'wc-licensed-product'),
                    'description' => '',
                    'hide_title' => true,
                    'callback' => [$this, 'renderDashboardPage'],
                ],
            ],
        ];

        return $reports;
    }

    /**
     * Enqueue admin styles and scripts
     */
    public function enqueueStyles(string $hook): void
    {
        // Check for our pages and WooCommerce Reports page with licenses tab
        $isLicensePage = in_array($hook, ['woocommerce_page_wc-licenses', 'woocommerce_page_wc-license-dashboard'], true);
        $isReportsPage = $hook === 'woocommerce_page_wc-reports' && isset($_GET['tab']) && $_GET['tab'] === 'licenses';

        if (!$isLicensePage && !$isReportsPage) {
            return;
        }

        wp_enqueue_style(
            'wc-licensed-product-admin',
            WC_LICENSED_PRODUCT_PLUGIN_URL . 'assets/css/admin.css',
            [],
            WC_LICENSED_PRODUCT_VERSION
        );

        // Enqueue live search script on licenses page
        if ($isLicensePage) {
            wp_enqueue_script(
                'wc-licensed-product-admin',
                WC_LICENSED_PRODUCT_PLUGIN_URL . 'assets/js/admin-licenses.js',
                ['jquery'],
                WC_LICENSED_PRODUCT_VERSION,
                true
            );

            wp_localize_script('wc-licensed-product-admin', 'wclpAdmin', [
                'ajaxUrl' => admin_url('admin-ajax.php'),
                'nonce' => wp_create_nonce('wclp_live_search'),
                'strings' => [
                    'noResults' => __('No licenses found', 'wc-licensed-product'),
                    'searching' => __('Searching...', 'wc-licensed-product'),
                    'error' => __('Search failed', 'wc-licensed-product'),
                ],
            ]);
        }
    }

    /**
     * Handle AJAX live search request
     */
    public function handleLiveSearch(): void
    {
        check_ajax_referer('wclp_live_search', 'nonce');

        if (!current_user_can('manage_woocommerce')) {
            wp_send_json_error(['message' => __('Permission denied.', 'wc-licensed-product')], 403);
        }

        $search = isset($_GET['search']) ? sanitize_text_field($_GET['search']) : '';

        if (strlen($search) < 2) {
            wp_send_json_success(['results' => []]);
        }

        $filters = ['search' => $search];
        $licenses = $this->licenseManager->getAllLicenses(1, 10, $filters);

        $results = [];
        foreach ($licenses as $license) {
            $product = wc_get_product($license->getProductId());
            $customer = get_userdata($license->getCustomerId());

            $results[] = [
                'id' => $license->getId(),
                'license_key' => $license->getLicenseKey(),
                'domain' => $license->getDomain(),
                'status' => $license->getStatus(),
                'product_name' => $product ? $product->get_name() : __('Unknown', 'wc-licensed-product'),
                'customer_name' => $customer ? $customer->display_name : __('Guest', 'wc-licensed-product'),
                'customer_email' => $customer ? $customer->user_email : '',
                'view_url' => admin_url('admin.php?page=wc-licenses&s=' . urlencode($license->getLicenseKey())),
            ];
        }

        wp_send_json_success(['results' => $results]);
    }

    /**
     * Handle admin actions (update, delete licenses)
     */
    public function handleAdminActions(): void
    {
        if (!isset($_GET['page']) || $_GET['page'] !== 'wc-licenses') {
            return;
        }

        if (!current_user_can('manage_woocommerce')) {
            return;
        }

        // Handle status update
        if (isset($_POST['action']) && $_POST['action'] === 'update_license_status') {
            $this->handleStatusUpdate();
        }

        // Handle delete
        if (isset($_GET['action']) && $_GET['action'] === 'delete' && isset($_GET['license_id'])) {
            $this->handleDelete();
        }

        // Handle revoke
        if (isset($_GET['action']) && $_GET['action'] === 'revoke' && isset($_GET['license_id'])) {
            $this->handleRevoke();
        }

        // Handle extend
        if (isset($_GET['action']) && $_GET['action'] === 'extend' && isset($_GET['license_id'])) {
            $this->handleExtend();
        }

        // Handle set lifetime
        if (isset($_GET['action']) && $_GET['action'] === 'lifetime' && isset($_GET['license_id'])) {
            $this->handleSetLifetime();
        }

        // Handle bulk actions
        if (isset($_POST['bulk_action']) && !empty($_POST['license_ids'])) {
            $this->handleBulkAction();
        }

        // Handle transfer
        if (isset($_POST['action']) && $_POST['action'] === 'transfer_license') {
            $this->handleTransfer();
        }

        // Handle CSV export
        if (isset($_GET['action']) && $_GET['action'] === 'export_csv') {
            $this->handleCsvExport();
        }

        // Handle CSV import page
        if (isset($_GET['action']) && $_GET['action'] === 'import_csv') {
            // Show import form - handled in renderImportPage
        }

        // Handle CSV import upload
        if (isset($_POST['action']) && $_POST['action'] === 'process_import_csv') {
            $this->handleCsvImport();
        }
    }

    /**
     * Handle license status update
     */
    private function handleStatusUpdate(): void
    {
        if (!wp_verify_nonce($_POST['_wpnonce'] ?? '', 'update_license_status')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        $licenseId = absint($_POST['license_id'] ?? 0);
        $status = sanitize_text_field($_POST['status'] ?? '');

        if ($licenseId && in_array($status, [License::STATUS_ACTIVE, License::STATUS_INACTIVE, License::STATUS_REVOKED], true)) {
            $this->licenseManager->updateLicenseStatus($licenseId, $status);

            wp_redirect(admin_url('admin.php?page=wc-licenses&updated=1'));
            exit;
        }
    }

    /**
     * Handle license deletion
     */
    private function handleDelete(): void
    {
        if (!wp_verify_nonce($_GET['_wpnonce'] ?? '', 'delete_license')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        $licenseId = absint($_GET['license_id'] ?? 0);
        if ($licenseId) {
            $this->licenseManager->deleteLicense($licenseId);

            wp_redirect(admin_url('admin.php?page=wc-licenses&deleted=1'));
            exit;
        }
    }

    /**
     * Handle license revocation
     */
    private function handleRevoke(): void
    {
        if (!wp_verify_nonce($_GET['_wpnonce'] ?? '', 'revoke_license')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        $licenseId = absint($_GET['license_id'] ?? 0);
        if ($licenseId) {
            $this->licenseManager->updateLicenseStatus($licenseId, License::STATUS_REVOKED);

            wp_redirect(admin_url('admin.php?page=wc-licenses&revoked=1'));
            exit;
        }
    }

    /**
     * Handle license extension
     */
    private function handleExtend(): void
    {
        if (!wp_verify_nonce($_GET['_wpnonce'] ?? '', 'extend_license')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        $licenseId = absint($_GET['license_id'] ?? 0);
        $days = absint($_GET['days'] ?? 30);

        if ($licenseId && $days > 0) {
            $this->licenseManager->extendLicense($licenseId, $days);

            wp_redirect(admin_url('admin.php?page=wc-licenses&extended=1'));
            exit;
        }
    }

    /**
     * Handle set license to lifetime
     */
    private function handleSetLifetime(): void
    {
        if (!wp_verify_nonce($_GET['_wpnonce'] ?? '', 'lifetime_license')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        $licenseId = absint($_GET['license_id'] ?? 0);
        if ($licenseId) {
            $this->licenseManager->setLicenseLifetime($licenseId);

            wp_redirect(admin_url('admin.php?page=wc-licenses&lifetime=1'));
            exit;
        }
    }

    /**
     * Handle license transfer
     */
    private function handleTransfer(): void
    {
        if (!wp_verify_nonce($_POST['_wpnonce'] ?? '', 'transfer_license')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        $licenseId = absint($_POST['license_id'] ?? 0);
        $newDomain = sanitize_text_field($_POST['new_domain'] ?? '');

        if ($licenseId && !empty($newDomain)) {
            $success = $this->licenseManager->transferLicense($licenseId, $newDomain);

            if ($success) {
                wp_redirect(admin_url('admin.php?page=wc-licenses&transferred=1'));
            } else {
                wp_redirect(admin_url('admin.php?page=wc-licenses&transfer_failed=1'));
            }
            exit;
        }

        wp_redirect(admin_url('admin.php?page=wc-licenses'));
        exit;
    }

    /**
     * Handle CSV export
     */
    private function handleCsvExport(): void
    {
        if (!current_user_can('manage_woocommerce')) {
            wp_die(__('You do not have permission to export licenses.', 'wc-licensed-product'));
        }

        $data = $this->licenseManager->exportLicensesForCsv();

        if (empty($data)) {
            wp_redirect(admin_url('admin.php?page=wc-licenses&export_empty=1'));
            exit;
        }

        // Set headers for CSV download
        $filename = 'licenses-export-' . gmdate('Y-m-d-His') . '.csv';
        header('Content-Type: text/csv; charset=utf-8');
        header('Content-Disposition: attachment; filename=' . $filename);
        header('Pragma: no-cache');
        header('Expires: 0');

        $output = fopen('php://output', 'w');

        // Write BOM for UTF-8
        fwrite($output, "\xEF\xBB\xBF");

        // Write header row
        fputcsv($output, array_keys($data[0]));

        // Write data rows
        foreach ($data as $row) {
            fputcsv($output, $row);
        }

        fclose($output);
        exit;
    }

    /**
     * Handle CSV import
     */
    private function handleCsvImport(): void
    {
        if (!wp_verify_nonce($_POST['_wpnonce'] ?? '', 'import_licenses_csv')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        if (!current_user_can('manage_woocommerce')) {
            wp_die(__('You do not have permission to import licenses.', 'wc-licensed-product'));
        }

        // Check if file was uploaded
        if (!isset($_FILES['import_file']) || $_FILES['import_file']['error'] !== UPLOAD_ERR_OK) {
            wp_redirect(admin_url('admin.php?page=wc-licenses&action=import_csv&import_error=upload'));
            exit;
        }

        $file = $_FILES['import_file'];

        // Validate file type
        $fileType = wp_check_filetype($file['name']);
        if ($fileType['ext'] !== 'csv') {
            wp_redirect(admin_url('admin.php?page=wc-licenses&action=import_csv&import_error=filetype'));
            exit;
        }

        // Read the CSV file
        $handle = fopen($file['tmp_name'], 'r');
        if (!$handle) {
            wp_redirect(admin_url('admin.php?page=wc-licenses&action=import_csv&import_error=read'));
            exit;
        }

        // Get import options
        $skipFirstRow = isset($_POST['skip_first_row']) && $_POST['skip_first_row'] === '1';
        $updateExisting = isset($_POST['update_existing']) && $_POST['update_existing'] === '1';

        // Skip BOM if present
        $bom = fread($handle, 3);
        if ($bom !== "\xEF\xBB\xBF") {
            rewind($handle);
        }

        // Read header row if skipping
        if ($skipFirstRow) {
            fgetcsv($handle);
        }

        $imported = 0;
        $updated = 0;
        $skipped = 0;
        $errors = [];

        while (($row = fgetcsv($handle)) !== false) {
            // Skip empty rows
            if (empty($row) || (count($row) === 1 && empty($row[0]))) {
                continue;
            }

            // Map CSV columns (expected format from export):
            // ID, License Key, Product, Product ID, Order ID, Order Number, Customer, Customer Email, Customer ID, Domain, Status, Activations, Max Activations, Expires At, Created At, Updated At
            // For import we need: License Key (or generate), Product ID, Customer ID, Domain, Status, Max Activations, Expires At
            $result = $this->processImportRow($row, $updateExisting);

            if ($result === 'imported') {
                $imported++;
            } elseif ($result === 'updated') {
                $updated++;
            } elseif ($result === 'skipped') {
                $skipped++;
            } else {
                $errors[] = $result;
            }
        }

        fclose($handle);

        // Build redirect URL with results
        $redirectUrl = add_query_arg([
            'page' => 'wc-licenses',
            'imported' => $imported,
            'updated' => $updated,
            'skipped' => $skipped,
            'import_errors' => count($errors),
        ], admin_url('admin.php'));

        wp_redirect($redirectUrl);
        exit;
    }

    /**
     * Process a single import row
     *
     * @param array $row CSV row data
     * @param bool $updateExisting Whether to update existing licenses
     * @return string Result: 'imported', 'updated', 'skipped', or error message
     */
    private function processImportRow(array $row, bool $updateExisting): string
    {
        // Determine if this is from our export format or simplified format
        // Export format has 16 columns, simplified has fewer

        if (count($row) >= 10) {
            // Full export format
            $licenseKey = trim($row[1] ?? '');
            $productId = absint($row[3] ?? 0);
            $orderId = absint($row[4] ?? 0);
            $customerId = absint($row[8] ?? 0);
            $domain = trim($row[9] ?? '');
            $status = strtolower(trim($row[10] ?? 'active'));
            $activationsCount = absint($row[11] ?? 1);
            $maxActivations = absint($row[12] ?? 1);
            $expiresAt = trim($row[13] ?? '');
        } else {
            // Simplified format: License Key, Product ID, Customer ID, Domain, Status, Max Activations, Expires At
            $licenseKey = trim($row[0] ?? '');
            $productId = absint($row[1] ?? 0);
            $customerId = absint($row[2] ?? 0);
            $domain = trim($row[3] ?? '');
            $status = strtolower(trim($row[4] ?? 'active'));
            $maxActivations = absint($row[5] ?? 1);
            $expiresAt = trim($row[6] ?? '');
            $orderId = 0;
            $activationsCount = 1;
        }

        // Validate required fields
        if (empty($domain)) {
            return sprintf(__('Row missing domain', 'wc-licensed-product'));
        }

        if ($productId <= 0) {
            return sprintf(__('Row missing valid product ID', 'wc-licensed-product'));
        }

        // Check if license key already exists
        if (!empty($licenseKey)) {
            $existing = $this->licenseManager->getLicenseByKey($licenseKey);
            if ($existing) {
                if ($updateExisting) {
                    // Update existing license
                    $this->licenseManager->updateLicenseDomain($existing->getId(), $domain);
                    if (in_array($status, [License::STATUS_ACTIVE, License::STATUS_INACTIVE, License::STATUS_REVOKED], true)) {
                        $this->licenseManager->updateLicenseStatus($existing->getId(), $status);
                    }
                    return 'updated';
                }
                return 'skipped';
            }
        } else {
            // Generate new license key
            $licenseKey = $this->licenseManager->generateLicenseKey();
            while ($this->licenseManager->getLicenseByKey($licenseKey)) {
                $licenseKey = $this->licenseManager->generateLicenseKey();
            }
        }

        // Normalize status
        if (!in_array($status, [License::STATUS_ACTIVE, License::STATUS_INACTIVE, License::STATUS_EXPIRED, License::STATUS_REVOKED], true)) {
            $status = License::STATUS_ACTIVE;
        }

        // Parse expiration date
        $expiresAtParsed = null;
        if (!empty($expiresAt) && strtolower($expiresAt) !== 'lifetime') {
            try {
                $expiresAtParsed = new \DateTimeImmutable($expiresAt);
            } catch (\Exception $e) {
                // Invalid date, leave as null (lifetime)
            }
        }

        // Create the license
        $result = $this->licenseManager->importLicense(
            $licenseKey,
            $productId,
            $customerId,
            $domain,
            $orderId,
            $status,
            $maxActivations,
            $activationsCount,
            $expiresAtParsed
        );

        return $result ? 'imported' : sprintf(__('Failed to import license for domain %s', 'wc-licensed-product'), $domain);
    }

    /**
     * Handle bulk actions
     */
    private function handleBulkAction(): void
    {
        if (!wp_verify_nonce($_POST['_wpnonce'] ?? '', 'bulk_license_action')) {
            wp_die(__('Security check failed.', 'wc-licensed-product'));
        }

        $action = sanitize_text_field($_POST['bulk_action'] ?? '');
        $licenseIds = array_map('absint', (array) ($_POST['license_ids'] ?? []));

        if (empty($licenseIds)) {
            wp_redirect(admin_url('admin.php?page=wc-licenses'));
            exit;
        }

        $count = 0;

        switch ($action) {
            case 'activate':
                $count = $this->licenseManager->bulkUpdateStatus($licenseIds, License::STATUS_ACTIVE);
                wp_redirect(admin_url('admin.php?page=wc-licenses&bulk_activated=' . $count));
                break;

            case 'deactivate':
                $count = $this->licenseManager->bulkUpdateStatus($licenseIds, License::STATUS_INACTIVE);
                wp_redirect(admin_url('admin.php?page=wc-licenses&bulk_deactivated=' . $count));
                break;

            case 'revoke':
                $count = $this->licenseManager->bulkUpdateStatus($licenseIds, License::STATUS_REVOKED);
                wp_redirect(admin_url('admin.php?page=wc-licenses&bulk_revoked=' . $count));
                break;

            case 'delete':
                $count = $this->licenseManager->bulkDelete($licenseIds);
                wp_redirect(admin_url('admin.php?page=wc-licenses&bulk_deleted=' . $count));
                break;

            case 'extend_30':
                $count = $this->licenseManager->bulkExtend($licenseIds, 30);
                wp_redirect(admin_url('admin.php?page=wc-licenses&bulk_extended=' . $count));
                break;

            case 'extend_90':
                $count = $this->licenseManager->bulkExtend($licenseIds, 90);
                wp_redirect(admin_url('admin.php?page=wc-licenses&bulk_extended=' . $count));
                break;

            case 'extend_365':
                $count = $this->licenseManager->bulkExtend($licenseIds, 365);
                wp_redirect(admin_url('admin.php?page=wc-licenses&bulk_extended=' . $count));
                break;

            default:
                wp_redirect(admin_url('admin.php?page=wc-licenses'));
        }

        exit;
    }

    /**
     * Render license dashboard page
     */
    public function renderDashboardPage(): void
    {
        $stats = $this->licenseManager->getStatistics();

        try {
            echo $this->twig->render('admin/dashboard.html.twig', [
                'stats' => $stats,
                'admin_url' => admin_url('admin.php'),
            ]);
        } catch (\Exception $e) {
            // Fallback to PHP template
            $this->renderDashboardPageFallback($stats);
        }
    }

    /**
     * Fallback render for dashboard page
     */
    private function renderDashboardPageFallback(array $stats): void
    {
        ?>
        <div class="wrap wclp-dashboard">
            <h1><?php esc_html_e('License Dashboard', 'wc-licensed-product'); ?></h1>

            <div class="wclp-dashboard-stats">
                <div class="wclp-stat-cards">
                    <div class="wclp-stat-card wclp-stat-total">
                        <div class="wclp-stat-icon"><span class="dashicons dashicons-admin-network"></span></div>
                        <div class="wclp-stat-content">
                            <span class="wclp-stat-number"><?php echo esc_html($stats['total']); ?></span>
                            <span class="wclp-stat-label"><?php esc_html_e('Total Licenses', 'wc-licensed-product'); ?></span>
                        </div>
                    </div>
                    <div class="wclp-stat-card wclp-stat-active">
                        <div class="wclp-stat-icon"><span class="dashicons dashicons-yes-alt"></span></div>
                        <div class="wclp-stat-content">
                            <span class="wclp-stat-number"><?php echo esc_html($stats['by_status'][License::STATUS_ACTIVE]); ?></span>
                            <span class="wclp-stat-label"><?php esc_html_e('Active', 'wc-licensed-product'); ?></span>
                        </div>
                    </div>
                    <div class="wclp-stat-card wclp-stat-inactive">
                        <div class="wclp-stat-icon"><span class="dashicons dashicons-marker"></span></div>
                        <div class="wclp-stat-content">
                            <span class="wclp-stat-number"><?php echo esc_html($stats['by_status'][License::STATUS_INACTIVE]); ?></span>
                            <span class="wclp-stat-label"><?php esc_html_e('Inactive', 'wc-licensed-product'); ?></span>
                        </div>
                    </div>
                    <div class="wclp-stat-card wclp-stat-expired">
                        <div class="wclp-stat-icon"><span class="dashicons dashicons-calendar-alt"></span></div>
                        <div class="wclp-stat-content">
                            <span class="wclp-stat-number"><?php echo esc_html($stats['by_status'][License::STATUS_EXPIRED]); ?></span>
                            <span class="wclp-stat-label"><?php esc_html_e('Expired', 'wc-licensed-product'); ?></span>
                        </div>
                    </div>
                    <div class="wclp-stat-card wclp-stat-revoked">
                        <div class="wclp-stat-icon"><span class="dashicons dashicons-dismiss"></span></div>
                        <div class="wclp-stat-content">
                            <span class="wclp-stat-number"><?php echo esc_html($stats['by_status'][License::STATUS_REVOKED]); ?></span>
                            <span class="wclp-stat-label"><?php esc_html_e('Revoked', 'wc-licensed-product'); ?></span>
                        </div>
                    </div>
                </div>

                <?php if ($stats['expiring_soon'] > 0): ?>
                <div class="notice notice-warning">
                    <p>
                        <span class="dashicons dashicons-warning"></span>
                        <strong><?php esc_html_e('Attention:', 'wc-licensed-product'); ?></strong>
                        <?php
                        printf(
                            /* translators: %d: number of licenses expiring */
                            _n(
                                '%d license is expiring within the next 30 days.',
                                '%d licenses are expiring within the next 30 days.',
                                $stats['expiring_soon'],
                                'wc-licensed-product'
                            ),
                            $stats['expiring_soon']
                        );
                        ?>
                        <a href="<?php echo esc_url(admin_url('admin.php?page=wc-licenses')); ?>"><?php esc_html_e('View Licenses', 'wc-licensed-product'); ?></a>
                    </p>
                </div>
                <?php endif; ?>

                <div class="wclp-dashboard-actions">
                    <h2><?php esc_html_e('Quick Actions', 'wc-licensed-product'); ?></h2>
                    <div class="wclp-action-buttons">
                        <a href="<?php echo esc_url(admin_url('admin.php?page=wc-licenses')); ?>" class="button button-primary">
                            <span class="dashicons dashicons-admin-network"></span>
                            <?php esc_html_e('Manage Licenses', 'wc-licensed-product'); ?>
                        </a>
                        <a href="<?php echo esc_url(admin_url('admin.php?page=wc-licenses&action=export_csv')); ?>" class="button">
                            <span class="dashicons dashicons-download"></span>
                            <?php esc_html_e('Export to CSV', 'wc-licensed-product'); ?>
                        </a>
                        <a href="<?php echo esc_url(admin_url('admin.php?page=wc-settings&tab=licensed_product')); ?>" class="button">
                            <span class="dashicons dashicons-admin-generic"></span>
                            <?php esc_html_e('Settings', 'wc-licensed-product'); ?>
                        </a>
                    </div>
                </div>
            </div>
        </div>
        <?php
    }

    /**
     * Render licenses admin page
     */
    public function renderLicensesPage(): void
    {
        // Check if showing import page
        if (isset($_GET['action']) && $_GET['action'] === 'import_csv') {
            $this->renderImportPage();
            return;
        }

        $page = isset($_GET['paged']) ? absint($_GET['paged']) : 1;
        $perPage = 20;

        // Build filters from query params
        $filters = [];
        if (!empty($_GET['s'])) {
            $filters['search'] = sanitize_text_field($_GET['s']);
        }
        if (!empty($_GET['status']) && $_GET['status'] !== 'all') {
            $filters['status'] = sanitize_text_field($_GET['status']);
        }
        if (!empty($_GET['product_id'])) {
            $filters['product_id'] = absint($_GET['product_id']);
        }

        $licenses = $this->licenseManager->getAllLicenses($page, $perPage, $filters);
        $totalLicenses = $this->licenseManager->getLicenseCount($filters);
        $totalPages = (int) ceil($totalLicenses / $perPage);

        // Get products for filter dropdown
        $licensedProducts = $this->licenseManager->getLicensedProducts();

        // Enrich licenses with related data
        $enrichedLicenses = [];
        foreach ($licenses as $license) {
            $product = wc_get_product($license->getProductId());
            $order = wc_get_order($license->getOrderId());
            $customer = get_userdata($license->getCustomerId());

            $enrichedLicenses[] = [
                'license' => $license,
                'product_name' => $product ? $product->get_name() : __('Unknown', 'wc-licensed-product'),
                'product_edit_url' => $product ? get_edit_post_link($product->get_id()) : '',
                'order_number' => $order ? $order->get_order_number() : '',
                'order_edit_url' => $order ? $order->get_edit_order_url() : '',
                'customer_name' => $customer ? $customer->display_name : __('Guest', 'wc-licensed-product'),
                'customer_email' => $customer ? $customer->user_email : '',
            ];
        }

        // Add URL helper functions to Twig
        $this->twig->addFunction(new \Twig\TwigFunction('extend_url', function (int $licenseId, int $days = 30): string {
            return wp_nonce_url(
                admin_url('admin.php?page=wc-licenses&action=extend&license_id=' . $licenseId . '&days=' . $days),
                'extend_license'
            );
        }));
        $this->twig->addFunction(new \Twig\TwigFunction('lifetime_url', function (int $licenseId): string {
            return wp_nonce_url(
                admin_url('admin.php?page=wc-licenses&action=lifetime&license_id=' . $licenseId),
                'lifetime_license'
            );
        }));
        $this->twig->addFunction(new \Twig\TwigFunction('revoke_url', function (int $licenseId): string {
            return wp_nonce_url(
                admin_url('admin.php?page=wc-licenses&action=revoke&license_id=' . $licenseId),
                'revoke_license'
            );
        }));
        $this->twig->addFunction(new \Twig\TwigFunction('delete_url', function (int $licenseId): string {
            return wp_nonce_url(
                admin_url('admin.php?page=wc-licenses&action=delete&license_id=' . $licenseId),
                'delete_license'
            );
        }));
        $this->twig->addFunction(new \Twig\TwigFunction('transfer_nonce', function (): string {
            return wp_create_nonce('transfer_license');
        }));

        try {
            echo $this->twig->render('admin/licenses.html.twig', [
                'licenses' => $enrichedLicenses,
                'current_page' => $page,
                'total_pages' => $totalPages,
                'total_licenses' => $totalLicenses,
                'admin_url' => admin_url('admin.php?page=wc-licenses'),
                'notices' => $this->getNotices(),
                'filters' => $filters,
                'products' => $licensedProducts,
            ]);
        } catch (\Exception $e) {
            // Fallback to PHP template
            $this->renderLicensesPageFallback($enrichedLicenses, $page, $totalPages, $totalLicenses, $filters, $licensedProducts);
        }
    }

    /**
     * Get admin notices
     */
    private function getNotices(): array
    {
        $notices = [];

        if (isset($_GET['updated'])) {
            $notices[] = ['type' => 'success', 'message' => __('License updated successfully.', 'wc-licensed-product')];
        }
        if (isset($_GET['deleted'])) {
            $notices[] = ['type' => 'success', 'message' => __('License deleted successfully.', 'wc-licensed-product')];
        }
        if (isset($_GET['revoked'])) {
            $notices[] = ['type' => 'success', 'message' => __('License revoked successfully.', 'wc-licensed-product')];
        }
        if (isset($_GET['extended'])) {
            $notices[] = ['type' => 'success', 'message' => __('License extended successfully.', 'wc-licensed-product')];
        }
        if (isset($_GET['lifetime'])) {
            $notices[] = ['type' => 'success', 'message' => __('License set to lifetime successfully.', 'wc-licensed-product')];
        }
        if (isset($_GET['bulk_activated'])) {
            $count = absint($_GET['bulk_activated']);
            $notices[] = ['type' => 'success', 'message' => sprintf(
                /* translators: %d: number of licenses */
                _n('%d license activated.', '%d licenses activated.', $count, 'wc-licensed-product'),
                $count
            )];
        }
        if (isset($_GET['bulk_deactivated'])) {
            $count = absint($_GET['bulk_deactivated']);
            $notices[] = ['type' => 'success', 'message' => sprintf(
                /* translators: %d: number of licenses */
                _n('%d license deactivated.', '%d licenses deactivated.', $count, 'wc-licensed-product'),
                $count
            )];
        }
        if (isset($_GET['bulk_revoked'])) {
            $count = absint($_GET['bulk_revoked']);
            $notices[] = ['type' => 'success', 'message' => sprintf(
                /* translators: %d: number of licenses */
                _n('%d license revoked.', '%d licenses revoked.', $count, 'wc-licensed-product'),
                $count
            )];
        }
        if (isset($_GET['bulk_deleted'])) {
            $count = absint($_GET['bulk_deleted']);
            $notices[] = ['type' => 'success', 'message' => sprintf(
                /* translators: %d: number of licenses */
                _n('%d license deleted.', '%d licenses deleted.', $count, 'wc-licensed-product'),
                $count
            )];
        }
        if (isset($_GET['bulk_extended'])) {
            $count = absint($_GET['bulk_extended']);
            $notices[] = ['type' => 'success', 'message' => sprintf(
                /* translators: %d: number of licenses */
                _n('%d license extended.', '%d licenses extended.', $count, 'wc-licensed-product'),
                $count
            )];
        }
        if (isset($_GET['transferred'])) {
            $notices[] = ['type' => 'success', 'message' => __('License transferred to new domain successfully.', 'wc-licensed-product')];
        }
        if (isset($_GET['transfer_failed'])) {
            $notices[] = ['type' => 'error', 'message' => __('Failed to transfer license. The license may be revoked or invalid.', 'wc-licensed-product')];
        }
        if (isset($_GET['export_empty'])) {
            $notices[] = ['type' => 'warning', 'message' => __('No licenses to export.', 'wc-licensed-product')];
        }
        if (isset($_GET['imported'])) {
            $imported = absint($_GET['imported']);
            $updated = absint($_GET['updated'] ?? 0);
            $skipped = absint($_GET['skipped'] ?? 0);
            $errors = absint($_GET['import_errors'] ?? 0);

            $message = sprintf(
                /* translators: %d: number of licenses imported */
                _n('%d license imported.', '%d licenses imported.', $imported, 'wc-licensed-product'),
                $imported
            );

            if ($updated > 0) {
                $message .= ' ' . sprintf(
                    /* translators: %d: number of licenses updated */
                    _n('%d updated.', '%d updated.', $updated, 'wc-licensed-product'),
                    $updated
                );
            }

            if ($skipped > 0) {
                $message .= ' ' . sprintf(
                    /* translators: %d: number of licenses skipped */
                    _n('%d skipped.', '%d skipped.', $skipped, 'wc-licensed-product'),
                    $skipped
                );
            }

            if ($errors > 0) {
                $message .= ' ' . sprintf(
                    /* translators: %d: number of errors */
                    _n('%d error.', '%d errors.', $errors, 'wc-licensed-product'),
                    $errors
                );
            }

            $notices[] = ['type' => 'success', 'message' => $message];
        }

        return $notices;
    }

    /**
     * Fallback render for licenses page
     */
    private function renderLicensesPageFallback(array $enrichedLicenses, int $page, int $totalPages, int $totalLicenses, array $filters = [], array $products = []): void
    {
        ?>
        <div class="wrap">
            <h1 class="wp-heading-inline"><?php esc_html_e('Licenses', 'wc-licensed-product'); ?></h1>
            <a href="<?php echo esc_url(admin_url('admin.php?page=wc-licenses&action=export_csv')); ?>" class="page-title-action">
                <span class="dashicons dashicons-download" style="vertical-align: middle;"></span>
                <?php esc_html_e('Export CSV', 'wc-licensed-product'); ?>
            </a>
            <a href="<?php echo esc_url(admin_url('admin.php?page=wc-licenses&action=import_csv')); ?>" class="page-title-action">
                <span class="dashicons dashicons-upload" style="vertical-align: middle;"></span>
                <?php esc_html_e('Import CSV', 'wc-licensed-product'); ?>
            </a>
            <hr class="wp-header-end">

            <?php foreach ($this->getNotices() as $notice): ?>
                <div class="notice notice-<?php echo esc_attr($notice['type']); ?> is-dismissible">
                    <p><?php echo esc_html($notice['message']); ?></p>
                </div>
            <?php endforeach; ?>

            <!-- Search and Filter Form -->
            <form method="get" action="" class="wclp-filter-form">
                <input type="hidden" name="page" value="wc-licenses">

                <p class="search-box">
                    <label class="screen-reader-text" for="license-search-input"><?php esc_html_e('Search Licenses', 'wc-licensed-product'); ?></label>
                    <input type="search" id="license-search-input" name="s" value="<?php echo esc_attr($filters['search'] ?? ''); ?>"
                           placeholder="<?php esc_attr_e('Search license key or domain...', 'wc-licensed-product'); ?>">
                    <input type="submit" id="search-submit" class="button" value="<?php esc_attr_e('Search', 'wc-licensed-product'); ?>">
                </p>

                <div class="tablenav top">
                    <div class="alignleft actions">
                        <select name="status">
                            <option value="all"><?php esc_html_e('All Statuses', 'wc-licensed-product'); ?></option>
                            <option value="active" <?php selected($filters['status'] ?? '', 'active'); ?>><?php esc_html_e('Active', 'wc-licensed-product'); ?></option>
                            <option value="inactive" <?php selected($filters['status'] ?? '', 'inactive'); ?>><?php esc_html_e('Inactive', 'wc-licensed-product'); ?></option>
                            <option value="expired" <?php selected($filters['status'] ?? '', 'expired'); ?>><?php esc_html_e('Expired', 'wc-licensed-product'); ?></option>
                            <option value="revoked" <?php selected($filters['status'] ?? '', 'revoked'); ?>><?php esc_html_e('Revoked', 'wc-licensed-product'); ?></option>
                        </select>

                        <select name="product_id">
                            <option value=""><?php esc_html_e('All Products', 'wc-licensed-product'); ?></option>
                            <?php foreach ($products as $id => $name): ?>
                                <option value="<?php echo esc_attr($id); ?>" <?php selected($filters['product_id'] ?? '', $id); ?>><?php echo esc_html($name); ?></option>
                            <?php endforeach; ?>
                        </select>

                        <input type="submit" class="button" value="<?php esc_attr_e('Filter', 'wc-licensed-product'); ?>">

                        <?php if (!empty($filters)): ?>
                            <a href="<?php echo esc_url(admin_url('admin.php?page=wc-licenses')); ?>" class="button"><?php esc_html_e('Clear', 'wc-licensed-product'); ?></a>
                        <?php endif; ?>
                    </div>

                    <div class="tablenav-pages">
                        <span class="displaying-num"><?php echo esc_html($totalLicenses); ?> <?php echo $totalLicenses === 1 ? esc_html__('item', 'wc-licensed-product') : esc_html__('items', 'wc-licensed-product'); ?></span>
                    </div>
                </div>
            </form>

            <p class="description">
                <?php esc_html_e('Showing', 'wc-licensed-product'); ?> <?php echo esc_html($totalLicenses); ?> <?php echo $totalLicenses === 1 ? esc_html__('license', 'wc-licensed-product') : esc_html__('licenses', 'wc-licensed-product'); ?>
                <?php if (!empty($filters)): ?>
                    (<?php esc_html_e('filtered', 'wc-licensed-product'); ?>)
                <?php endif; ?>
                | <a href="<?php echo esc_url(admin_url('admin.php?page=wc-reports&tab=licenses')); ?>"><?php esc_html_e('View Dashboard', 'wc-licensed-product'); ?></a>
            </p>

            <form method="post" action="<?php echo esc_url(admin_url('admin.php?page=wc-licenses')); ?>">
                <?php wp_nonce_field('bulk_license_action'); ?>

                <div class="tablenav top">
                    <div class="alignleft actions bulkactions">
                        <select name="bulk_action" id="bulk-action-selector">
                            <option value=""><?php esc_html_e('Bulk Actions', 'wc-licensed-product'); ?></option>
                            <option value="activate"><?php esc_html_e('Activate', 'wc-licensed-product'); ?></option>
                            <option value="deactivate"><?php esc_html_e('Deactivate', 'wc-licensed-product'); ?></option>
                            <option value="revoke"><?php esc_html_e('Revoke', 'wc-licensed-product'); ?></option>
                            <option value="extend_30"><?php esc_html_e('Extend 30 days', 'wc-licensed-product'); ?></option>
                            <option value="extend_90"><?php esc_html_e('Extend 90 days', 'wc-licensed-product'); ?></option>
                            <option value="extend_365"><?php esc_html_e('Extend 1 year', 'wc-licensed-product'); ?></option>
                            <option value="delete"><?php esc_html_e('Delete', 'wc-licensed-product'); ?></option>
                        </select>
                        <input type="submit" class="button action" value="<?php esc_attr_e('Apply', 'wc-licensed-product'); ?>">
                    </div>
                </div>

                <table class="wp-list-table widefat fixed striped licenses-table">
                    <thead>
                        <tr>
                            <td class="manage-column column-cb check-column">
                                <input type="checkbox" id="cb-select-all-1">
                            </td>
                            <th><?php esc_html_e('License Key', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Product', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Customer', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Domain', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Status', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Expires', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Actions', 'wc-licensed-product'); ?></th>
                        </tr>
                    </thead>
                    <tbody>
                        <?php if (empty($enrichedLicenses)): ?>
                            <tr>
                                <td colspan="8"><?php esc_html_e('No licenses found.', 'wc-licensed-product'); ?></td>
                            </tr>
                        <?php else: ?>
                            <?php foreach ($enrichedLicenses as $item): ?>
                                <tr>
                                    <th scope="row" class="check-column">
                                        <input type="checkbox" name="license_ids[]" value="<?php echo esc_attr($item['license']->getId()); ?>">
                                    </th>
                                    <td><code><?php echo esc_html($item['license']->getLicenseKey()); ?></code></td>
                                    <td>
                                        <?php if ($item['product_edit_url']): ?>
                                            <a href="<?php echo esc_url($item['product_edit_url']); ?>">
                                                <?php echo esc_html($item['product_name']); ?>
                                            </a>
                                        <?php else: ?>
                                            <?php echo esc_html($item['product_name']); ?>
                                        <?php endif; ?>
                                    </td>
                                    <td>
                                        <?php echo esc_html($item['customer_name']); ?>
                                        <?php if ($item['customer_email']): ?>
                                            <br><small><?php echo esc_html($item['customer_email']); ?></small>
                                        <?php endif; ?>
                                    </td>
                                    <td><?php echo esc_html($item['license']->getDomain()); ?></td>
                                    <td>
                                        <span class="license-status license-status-<?php echo esc_attr($item['license']->getStatus()); ?>">
                                            <?php echo esc_html(ucfirst($item['license']->getStatus())); ?>
                                        </span>
                                    </td>
                                    <td>
                                        <?php
                                        $expiresAt = $item['license']->getExpiresAt();
                                        if ($expiresAt) {
                                            echo esc_html($expiresAt->format(get_option('date_format')));
                                        } else {
                                            echo '<span class="license-lifetime">' . esc_html__('Lifetime', 'wc-licensed-product') . '</span>';
                                        }
                                        ?>
                                    </td>
                                    <td class="license-actions">
                                        <div class="row-actions">
                                            <?php if ($item['license']->getStatus() !== License::STATUS_REVOKED): ?>
                                                <span class="extend">
                                                    <a href="<?php echo esc_url(wp_nonce_url(
                                                        admin_url('admin.php?page=wc-licenses&action=extend&license_id=' . $item['license']->getId() . '&days=30'),
                                                        'extend_license'
                                                    )); ?>" title="<?php esc_attr_e('Extend by 30 days', 'wc-licensed-product'); ?>">+30d</a> |
                                                </span>
                                                <span class="lifetime">
                                                    <a href="<?php echo esc_url(wp_nonce_url(
                                                        admin_url('admin.php?page=wc-licenses&action=lifetime&license_id=' . $item['license']->getId()),
                                                        'lifetime_license'
                                                    )); ?>" title="<?php esc_attr_e('Set to lifetime', 'wc-licensed-product'); ?>">∞</a> |
                                                </span>
                                                <span class="revoke">
                                                    <a href="<?php echo esc_url(wp_nonce_url(
                                                        admin_url('admin.php?page=wc-licenses&action=revoke&license_id=' . $item['license']->getId()),
                                                        'revoke_license'
                                                    )); ?>" onclick="return confirm('<?php esc_attr_e('Are you sure?', 'wc-licensed-product'); ?>')">
                                                        <?php esc_html_e('Revoke', 'wc-licensed-product'); ?>
                                                    </a> |
                                                </span>
                                            <?php endif; ?>
                                            <span class="delete">
                                                <a href="<?php echo esc_url(wp_nonce_url(
                                                    admin_url('admin.php?page=wc-licenses&action=delete&license_id=' . $item['license']->getId()),
                                                    'delete_license'
                                                )); ?>" class="submitdelete" onclick="return confirm('<?php esc_attr_e('Are you sure you want to delete this license?', 'wc-licensed-product'); ?>')">
                                                    <?php esc_html_e('Delete', 'wc-licensed-product'); ?>
                                                </a>
                                            </span>
                                        </div>
                                    </td>
                                </tr>
                            <?php endforeach; ?>
                        <?php endif; ?>
                    </tbody>
                    <tfoot>
                        <tr>
                            <td class="manage-column column-cb check-column">
                                <input type="checkbox" id="cb-select-all-2">
                            </td>
                            <th><?php esc_html_e('License Key', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Product', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Customer', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Domain', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Status', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Expires', 'wc-licensed-product'); ?></th>
                            <th><?php esc_html_e('Actions', 'wc-licensed-product'); ?></th>
                        </tr>
                    </tfoot>
                </table>

                <div class="tablenav bottom">
                    <div class="alignleft actions bulkactions">
                        <select name="bulk_action_2" id="bulk-action-selector-bottom">
                            <option value=""><?php esc_html_e('Bulk Actions', 'wc-licensed-product'); ?></option>
                            <option value="activate"><?php esc_html_e('Activate', 'wc-licensed-product'); ?></option>
                            <option value="deactivate"><?php esc_html_e('Deactivate', 'wc-licensed-product'); ?></option>
                            <option value="revoke"><?php esc_html_e('Revoke', 'wc-licensed-product'); ?></option>
                            <option value="extend_30"><?php esc_html_e('Extend 30 days', 'wc-licensed-product'); ?></option>
                            <option value="extend_90"><?php esc_html_e('Extend 90 days', 'wc-licensed-product'); ?></option>
                            <option value="extend_365"><?php esc_html_e('Extend 1 year', 'wc-licensed-product'); ?></option>
                            <option value="delete"><?php esc_html_e('Delete', 'wc-licensed-product'); ?></option>
                        </select>
                        <input type="submit" class="button action" value="<?php esc_attr_e('Apply', 'wc-licensed-product'); ?>">
                    </div>
                    <?php if ($totalPages > 1): ?>
                        <div class="tablenav-pages">
                            <?php
                            echo paginate_links([
                                'base' => admin_url('admin.php?page=wc-licenses&paged=%#%'),
                                'format' => '',
                                'current' => $page,
                                'total' => $totalPages,
                            ]);
                            ?>
                        </div>
                    <?php endif; ?>
                </div>
            </form>

            <script>
            (function($) {
                $('#cb-select-all-1, #cb-select-all-2').on('change', function() {
                    $('input[name="license_ids[]"]').prop('checked', this.checked);
                    $('#cb-select-all-1, #cb-select-all-2').prop('checked', this.checked);
                });
                $('#bulk-action-selector, #bulk-action-selector-bottom').on('change', function() {
                    $('#bulk-action-selector, #bulk-action-selector-bottom').val($(this).val());
                });
                $('form').on('submit', function() {
                    var topAction = $('#bulk-action-selector').val();
                    var bottomAction = $('#bulk-action-selector-bottom').val();
                    if (!topAction && bottomAction) {
                        $('#bulk-action-selector').val(bottomAction);
                    }
                });
            })(jQuery);
            </script>
        </div>
        <?php
    }

    /**
     * Render the CSV import page
     */
    private function renderImportPage(): void
    {
        $importError = $_GET['import_error'] ?? '';
        ?>
        <div class="wrap">
            <h1>
                <?php esc_html_e('Import Licenses', 'wc-licensed-product'); ?>
                <a href="<?php echo esc_url(admin_url('admin.php?page=wc-licenses')); ?>" class="page-title-action">
                    <?php esc_html_e('Back to Licenses', 'wc-licensed-product'); ?>
                </a>
            </h1>

            <?php if ($importError): ?>
                <div class="notice notice-error">
                    <p>
                        <?php
                        switch ($importError) {
                            case 'upload':
                                esc_html_e('Error uploading file. Please try again.', 'wc-licensed-product');
                                break;
                            case 'filetype':
                                esc_html_e('Invalid file type. Please upload a CSV file.', 'wc-licensed-product');
                                break;
                            case 'read':
                                esc_html_e('Error reading file. Please check the file format.', 'wc-licensed-product');
                                break;
                            default:
                                esc_html_e('An error occurred during import.', 'wc-licensed-product');
                        }
                        ?>
                    </p>
                </div>
            <?php endif; ?>

            <div class="card" style="max-width: 800px; padding: 20px;">
                <h2><?php esc_html_e('Import Licenses from CSV', 'wc-licensed-product'); ?></h2>

                <p class="description">
                    <?php esc_html_e('Upload a CSV file to import licenses. You can use the exported CSV format or a simplified format.', 'wc-licensed-product'); ?>
                </p>

                <h3><?php esc_html_e('CSV Format', 'wc-licensed-product'); ?></h3>
                <p class="description">
                    <?php esc_html_e('The CSV file should contain the following columns:', 'wc-licensed-product'); ?>
                </p>

                <div style="background: #f8f9fa; padding: 15px; border-radius: 4px; margin: 15px 0;">
                    <p><strong><?php esc_html_e('Full Format (from Export):', 'wc-licensed-product'); ?></strong></p>
                    <code style="display: block; margin-bottom: 10px; font-size: 12px;">ID, License Key, Product, Product ID, Order ID, Order Number, Customer, Customer Email, Customer ID, Domain, Status, Activations, Max Activations, Expires At, Created At, Updated At</code>

                    <p><strong><?php esc_html_e('Simplified Format:', 'wc-licensed-product'); ?></strong></p>
                    <code style="display: block; font-size: 12px;">License Key, Product ID, Customer ID, Domain, Status, Max Activations, Expires At</code>
                </div>

                <p class="description">
                    <strong><?php esc_html_e('Notes:', 'wc-licensed-product'); ?></strong><br>
                    - <?php esc_html_e('Leave License Key empty to auto-generate.', 'wc-licensed-product'); ?><br>
                    - <?php esc_html_e('Status can be: active, inactive, expired, revoked (defaults to active).', 'wc-licensed-product'); ?><br>
                    - <?php esc_html_e('Expires At should be in YYYY-MM-DD format or "Lifetime".', 'wc-licensed-product'); ?>
                </p>

                <hr style="margin: 20px 0;">

                <form method="post" action="<?php echo esc_url(admin_url('admin.php?page=wc-licenses')); ?>" enctype="multipart/form-data">
                    <?php wp_nonce_field('import_licenses_csv'); ?>
                    <input type="hidden" name="action" value="process_import_csv">

                    <table class="form-table">
                        <tr>
                            <th scope="row">
                                <label for="import_file"><?php esc_html_e('CSV File', 'wc-licensed-product'); ?></label>
                            </th>
                            <td>
                                <input type="file" name="import_file" id="import_file" accept=".csv" required>
                                <p class="description"><?php esc_html_e('Select a CSV file to import.', 'wc-licensed-product'); ?></p>
                            </td>
                        </tr>
                        <tr>
                            <th scope="row"><?php esc_html_e('Options', 'wc-licensed-product'); ?></th>
                            <td>
                                <label>
                                    <input type="checkbox" name="skip_first_row" value="1" checked>
                                    <?php esc_html_e('Skip first row (header row)', 'wc-licensed-product'); ?>
                                </label>
                                <br><br>
                                <label>
                                    <input type="checkbox" name="update_existing" value="1">
                                    <?php esc_html_e('Update existing licenses (by license key)', 'wc-licensed-product'); ?>
                                </label>
                                <p class="description">
                                    <?php esc_html_e('If enabled, licenses with matching keys will be updated instead of skipped.', 'wc-licensed-product'); ?>
                                </p>
                            </td>
                        </tr>
                    </table>

                    <p class="submit">
                        <button type="submit" class="button button-primary">
                            <span class="dashicons dashicons-upload" style="vertical-align: middle;"></span>
                            <?php esc_html_e('Import Licenses', 'wc-licensed-product'); ?>
                        </button>
                    </p>
                </form>
            </div>
        </div>
        <?php
    }

    /**
     * Add license column to orders list
     */
    public function addOrdersLicenseColumn(array $columns): array
    {
        $newColumns = [];
        foreach ($columns as $key => $value) {
            $newColumns[$key] = $value;
            if ($key === 'order_status') {
                $newColumns['license'] = __('License', 'wc-licensed-product');
            }
        }
        return $newColumns;
    }

    /**
     * Display license column content
     */
    public function displayOrdersLicenseColumn(string $column, int $postId): void
    {
        if ($column !== 'license') {
            return;
        }

        $order = wc_get_order($postId);
        $this->outputLicenseColumnContent($order);
    }

    /**
     * Display license column content (HPOS)
     */
    public function displayOrdersLicenseColumnHpos(string $column, \WC_Order $order): void
    {
        if ($column !== 'license') {
            return;
        }

        $this->outputLicenseColumnContent($order);
    }

    /**
     * Output license column content
     */
    private function outputLicenseColumnContent(?\WC_Order $order): void
    {
        if (!$order) {
            echo '—';
            return;
        }

        $hasLicensedProduct = false;
        foreach ($order->get_items() as $item) {
            $product = $item->get_product();
            if ($product && $product->is_type('licensed')) {
                $hasLicensedProduct = true;
                break;
            }
        }

        if (!$hasLicensedProduct) {
            echo '—';
            return;
        }

        $domain = $order->get_meta('_licensed_product_domain');
        if ($domain) {
            echo '<span class="dashicons dashicons-admin-network"></span> ' . esc_html($domain);
        } else {
            echo '<span class="dashicons dashicons-warning" title="' . esc_attr__('No domain specified', 'wc-licensed-product') . '"></span>';
        }
    }
}