// =============================================================================
// Notification Controller
// =============================================================================

import { Request, Response } from 'express';
import notificationService from '../services/notification.service';
import logger from '../utils/logger';

function isValidUUID(s: string): boolean {
  return /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i.test(s);
}

class NotificationController {
  /** GET /api/notifications — returns all notifications for the authenticated user. */
  async getNotifications(req: Request, res: Response): Promise<void> {
    try {
      const userId = req.user!.id;
      const notifications = await notificationService.getByUser(userId);
      res.status(200).json({ success: true, data: notifications });
    } catch (error) {
      logger.error('NotificationController.getNotifications error', { error });
      res.status(500).json({ success: false, message: 'Notifications konnten nicht geladen werden' });
    }
  }

  /** GET /api/notifications/count — returns unread count for the authenticated user. */
  async getUnreadCount(req: Request, res: Response): Promise<void> {
    try {
      const userId = req.user!.id;
      const count = await notificationService.getUnreadCount(userId);
      res.status(200).json({ success: true, data: { count } });
    } catch (error) {
      logger.error('NotificationController.getUnreadCount error', { error });
      res.status(500).json({ success: false, message: 'Anzahl konnte nicht geladen werden' });
    }
  }

  /** PATCH /api/notifications/:id/read — marks a single notification as read. */
  async markAsRead(req: Request, res: Response): Promise<void> {
    try {
      const { id } = req.params as Record<string, string>;
      if (!isValidUUID(id)) {
        res.status(400).json({ success: false, message: 'Ungültige Notification-ID' });
        return;
      }
      const userId = req.user!.id;
      const updated = await notificationService.markAsRead(id, userId);
      if (!updated) {
        res.status(404).json({ success: false, message: 'Notification nicht gefunden' });
        return;
      }
      res.status(200).json({ success: true, message: 'Als gelesen markiert' });
    } catch (error) {
      logger.error('NotificationController.markAsRead error', { error });
      res.status(500).json({ success: false, message: 'Notification konnte nicht aktualisiert werden' });
    }
  }

  /** POST /api/notifications/mark-all-read — marks all notifications as read. */
  async markAllRead(req: Request, res: Response): Promise<void> {
    try {
      const userId = req.user!.id;
      await notificationService.markAllRead(userId);
      res.status(200).json({ success: true, message: 'Alle als gelesen markiert' });
    } catch (error) {
      logger.error('NotificationController.markAllRead error', { error });
      res.status(500).json({ success: false, message: 'Notifications konnten nicht aktualisiert werden' });
    }
  }
  /** POST /api/notifications/dismiss-by-type — marks all unread notifications of a given type as read. */
  async dismissByType(req: Request, res: Response): Promise<void> {
    try {
      const { quellTyp } = req.body;
      if (!quellTyp || typeof quellTyp !== 'string') {
        res.status(400).json({ success: false, message: 'quellTyp ist erforderlich' });
        return;
      }
      const userId = req.user!.id;
      await notificationService.dismissByType(userId, quellTyp);
      res.status(200).json({ success: true, message: 'Notifications als gelesen markiert' });
    } catch (error) {
      logger.error('NotificationController.dismissByType error', { error });
      res.status(500).json({ success: false, message: 'Notifications konnten nicht aktualisiert werden' });
    }
  }

  /** DELETE /api/notifications/read — deletes all read notifications for the authenticated user. */
  async deleteAllRead(req: Request, res: Response): Promise<void> {
    try {
      const userId = req.user!.id;
      await notificationService.deleteAllRead(userId);
      res.status(200).json({ success: true, message: 'Gelesene Notifications gelöscht' });
    } catch (error) {
      logger.error('NotificationController.deleteAllRead error', { error });
      res.status(500).json({ success: false, message: 'Gelesene Notifications konnten nicht gelöscht werden' });
    }
  }
}

export default new NotificationController();