/**
 * API: Notifications List Endpoint
 * GET /api/notifications - Get user notifications
 * POST /api/notifications - Send a notification
 */

import type { NextApiRequest, NextApiResponse } from 'next';
import { getNotificationService } from '../../../lib/notifications';

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  const notificationService = getNotificationService();

  if (req.method === 'GET') {
    try {
      // In production, get userId from session/auth
      const userId = req.query.userId as string || 'demo-user';
      const unreadOnly = req.query.unreadOnly === 'true';
      const type = req.query.type as string;
      const limit = parseInt(req.query.limit as string) || 50;
      const offset = parseInt(req.query.offset as string) || 0;

      const notifications = notificationService.getUserNotifications(userId, {
        unreadOnly,
        type: type as any,
        limit,
        offset
      });

      const unreadCount = notificationService.getUnreadCount(userId);

      return res.status(200).json({
        success: true,
        data: {
          notifications,
          unreadCount,
          pagination: {
            limit,
            offset,
            hasMore: notifications.length === limit
          }
        }
      });
    } catch (error: any) {
      return res.status(500).json({
        success: false,
        error: error.message
      });
    }
  }

  if (req.method === 'POST') {
    try {
      const { recipientId, email, title, message, type, channels, priority, actionUrl, data } = req.body;

      if (!recipientId || !title || !message) {
        return res.status(400).json({
          success: false,
          error: 'Missing required fields: recipientId, title, message'
        });
      }

      const notification = await notificationService.send(
        { userId: recipientId, email },
        {
          type: type || 'system_alert',
          title,
          message,
          actionUrl,
          data
        },
        { channels, priority }
      );

      return res.status(201).json({
        success: true,
        data: notification
      });
    } catch (error: any) {
      return res.status(500).json({
        success: false,
        error: error.message
      });
    }
  }

  return res.status(405).json({ error: 'Method not allowed' });
}