update notif , now it is cursor based

src/modules/notifications/services/notification.service.ts

@@ -1,5 +1,5 @@
 import { Injectable, Logger, NotFoundException } from '@nestjs/common';
-import { EntityManager } from '@mikro-orm/postgresql';
+import { EntityManager, FilterQuery } from '@mikro-orm/postgresql';
 import { Notification } from '../entities/notification.entity';
 import { NotificationPreferenceService } from './notification-preference.service';
 import { NotificationQueueService } from './notification-queue.service';
@@ -108,15 +108,44 @@ export class NotificationService {
     );
   }
 
-  async findByUserAndRestaurant(userId: string, restaurantId: string, limit = 50): Promise<Notification[]> {
-    return this.em.find(
-      Notification,
-      { user: { id: userId }, restaurant: { id: restaurantId } },
-      {
-        orderBy: { createdAt: 'DESC' },
-        limit,
-      },
-    );
+  async findByUserAndRestaurant(
+    userId: string,
+    restaurantId: string,
+    limit = 50,
+    cursor?: string,
+    status?: 'seen' | 'unseen',
+  ): Promise<{ data: Notification[]; nextCursor: string | null }> {
+    const where: FilterQuery<Notification> = {
+      user: { id: userId },
+      restaurant: { id: restaurantId },
+    };
+
+    // Filter by status (seen/unseen)
+    if (status === 'seen') {
+      where.seenAt = { $ne: null };
+    } else if (status === 'unseen') {
+      where.seenAt = null;
+    }
+
+    // Cursor-based pagination: if cursor is provided, get items with id < cursor (since ULIDs are time-ordered)
+    if (cursor) {
+      where.id = { $lt: cursor };
+    }
+
+    const notifications = await this.em.find(Notification, where, {
+      orderBy: { createdAt: 'DESC', id: 'DESC' },
+      limit: limit + 1, // Fetch one extra to determine if there's a next page
+    });
+
+    // Check if there's a next page
+    const hasNextPage = notifications.length > limit;
+    const data = hasNextPage ? notifications.slice(0, limit) : notifications;
+    const nextCursor = hasNextPage && data.length > 0 ? data[data.length - 1].id : null;
+
+    return {
+      data,
+      nextCursor,
+    };
   }
 
   async readNotificationAdmin(id: string, adminId: string, restaurantId: string): Promise<void> {
@@ -128,7 +157,7 @@ export class NotificationService {
     if (!notification) {
       throw new NotFoundException('Notification not found');
     }
-    notification.sentAt = new Date();
+    notification.seenAt = new Date();
     await this.em.persistAndFlush(notification);
   }
   async readNotificationAsUser(id: string, userId: string, restaurantId: string): Promise<void> {
@@ -140,7 +169,7 @@ export class NotificationService {
     if (!notification) {
       throw new NotFoundException('Notification not found');
     }
-    notification.sentAt = new Date();
+    notification.seenAt = new Date();
     await this.em.persistAndFlush(notification);
   }