<?php
/**
 * License Handler for Academic Certificate Verification Plugin
 *
 * Add this file to your plugin: includes/class-license-handler.php
 * Then include it in your main plugin file
 */

defined('ABSPATH') || exit;

class ACCEVE_License_Handler {

    private static $instance = null;
    private $license_server = 'https://queuecommerce.com'; // Change to your actual domain
    private $product_name = 'Academic Certificate Verification Pro';

    public static function get_instance() {
        if (null === self::$instance) {
            self::$instance = new self();
        }
        return self::$instance;
    }

    private function __construct() {
        // Check license on plugin activation
        register_activation_hook(ACCEVE_PATH, array($this, 'on_plugin_activation'));

        // Add daily cron to verify license
        add_action('acceve_daily_license_check', array($this, 'verify_license_status'));

        // Schedule cron if not already scheduled
        if (!wp_next_scheduled('acceve_daily_license_check')) {
            wp_schedule_event(time(), 'daily', 'acceve_daily_license_check');
        }

        // Add AJAX handlers for license activation
        add_action('wp_ajax_acceve_activate_license', array($this, 'ajax_activate_license'));

        // Add admin notice for license issues
        add_action('admin_notices', array($this, 'license_admin_notices'));
    }

    /**
     * On plugin activation
     */
    public function on_plugin_activation() {
        $license_key = get_option('acceve_license_key');

        if (!empty($license_key)) {
            $this->activate_license($license_key);
        }
    }

    /**
     * Activate license on server
     */
    public function activate_license($license_key) {
        $domain = $this->get_domain();

        $response = wp_remote_post($this->license_server . '/wp-json/qc/v1/license/activate', array(
            'body' => array(
                'license_key' => $license_key,
                'domain' => $domain,
                'product' => $this->product_name
            ),
            'timeout' => 15
        ));

        if (is_wp_error($response)) {
            return array(
                'success' => false,
                'message' => 'Could not connect to license server: ' . $response->get_error_message()
            );
        }

        $body = wp_remote_retrieve_body($response);
        $data = json_decode($body, true);

        if ($data && isset($data['success']) && $data['success']) {
            // Store license data
            update_option('acceve_license_key', $license_key);
            update_option('acceve_license_status', 'active');
            update_option('acceve_license_data', $data['data']);

            // Store expiry date if provided
            if (isset($data['data']['expiry_date']) && !empty($data['data']['expiry_date'])) {
                update_option('acceve_license_expiry', $data['data']['expiry_date']);
            }

            update_option('acceve_license_last_check', time());

            return array(
                'success' => true,
                'message' => $data['message'] ?? 'License activated successfully',
                'data' => $data['data']
            );
        } else {
            return array(
                'success' => false,
                'message' => $data['message'] ?? 'Failed to activate license'
            );
        }
    }

    /**
     * Verify license status (called daily by cron)
     */
    public function verify_license_status() {
        $license_key = get_option('acceve_license_key');

        if (empty($license_key)) {
            return;
        }

        $domain = $this->get_domain();

        $response = wp_remote_post($this->license_server . '/wp-json/qc/v1/license/status', array(
            'body' => array(
                'license_key' => $license_key,
                'domain' => $domain
            ),
            'timeout' => 15
        ));

        if (!is_wp_error($response)) {
            $body = wp_remote_retrieve_body($response);
            $data = json_decode($body, true);

            if ($data && isset($data['success']) && $data['success']) {
                $license_data = $data['data'];

                // Update stored data
                update_option('acceve_license_data', $license_data);
                update_option('acceve_license_last_check', time());

                // Update status
                if ($license_data['is_expired'] || !$license_data['is_activated_on_domain']) {
                    update_option('acceve_license_status', 'inactive');
                } else {
                    update_option('acceve_license_status', 'active');
                }

                // Update expiry date
                if (isset($license_data['expiry_date'])) {
                    update_option('acceve_license_expiry', $license_data['expiry_date']);
                }
            }
        }
    }

    /**
     * AJAX: Activate license
     */
    public function ajax_activate_license() {
        check_ajax_referer('acceve_license_nonce', 'nonce');

        if (!current_user_can('manage_options')) {
            wp_send_json_error('Unauthorized');
        }

        $license_key = sanitize_text_field($_POST['license_key']);

        if (empty($license_key)) {
            wp_send_json_error('License key is required');
        }

        $result = $this->activate_license($license_key);

        if ($result['success']) {
            wp_send_json_success($result);
        } else {
            wp_send_json_error($result['message']);
        }
    }

    /**
     * Check if license is active
     */
    public function is_license_active() {
        $status = get_option('acceve_license_status');
        $expiry = get_option('acceve_license_expiry');

        if ($status !== 'active') {
            return false;
        }

        // Check expiry
        if (!empty($expiry) && strtotime($expiry) < time()) {
            update_option('acceve_license_status', 'inactive');
            return false;
        }

        return true;
    }

    /**
     * Get license info
     */
    public function get_license_info() {
        return array(
            'license_key' => get_option('acceve_license_key'),
            'status' => get_option('acceve_license_status'),
            'expiry' => get_option('acceve_license_expiry'),
            'data' => get_option('acceve_license_data'),
            'last_check' => get_option('acceve_license_last_check')
        );
    }

    /**
     * Admin notices for license issues
     */
    public function license_admin_notices() {
        // Only show on plugin pages
        $screen = get_current_screen();
        if (strpos($screen->id, 'certificate_verification') === false) {
            return;
        }

        $license_key = get_option('acceve_license_key');
        $status = get_option('acceve_license_status');
        $expiry = get_option('acceve_license_expiry');

        // No license key entered
        if (empty($license_key)) {
            ?>
            <div class="notice notice-warning">
                <p>
                    <strong><?php _e('Academic Certificate Verification Pro:', 'academic-certificate-verification'); ?></strong>
                    <?php _e('Please activate your license to use Pro features.', 'academic-certificate-verification'); ?>
                    <a href="<?php echo admin_url('admin.php?page=certificate_verification_pro'); ?>">
                        <?php _e('Activate License', 'academic-certificate-verification'); ?>
                    </a>
                </p>
            </div>
            <?php
            return;
        }

        // License expired
        if (!empty($expiry) && strtotime($expiry) < time()) {
            ?>
            <div class="notice notice-error">
                <p>
                    <strong><?php _e('Academic Certificate Verification Pro:', 'academic-certificate-verification'); ?></strong>
                    <?php _e('Your license has expired. Please renew to continue using Pro features.', 'academic-certificate-verification'); ?>
                    <?php if ($expiry): ?>
                        (<?php printf(__('Expired on: %s', 'academic-certificate-verification'), date('F j, Y', strtotime($expiry))); ?>)
                    <?php endif; ?>
                </p>
            </div>
            <?php
            return;
        }

        // License inactive but not expired
        if ($status !== 'active' && !empty($license_key)) {
            ?>
            <div class="notice notice-warning">
                <p>
                    <strong><?php _e('Academic Certificate Verification Pro:', 'academic-certificate-verification'); ?></strong>
                    <?php _e('Your license is not active. Please check your license status.', 'academic-certificate-verification'); ?>
                    <a href="<?php echo admin_url('admin.php?page=certificate_verification_pro'); ?>">
                        <?php _e('Check License', 'academic-certificate-verification'); ?>
                    </a>
                </p>
            </div>
            <?php
        }
    }

    /**
     * Get current domain
     */
    private function get_domain() {
        return parse_url(home_url(), PHP_URL_HOST);
    }
}

// Initialize
ACCEVE_License_Handler::get_instance();