import { Injectable, Logger } from '@nestjs/common';
import { InjectQueue } from '@nestjs/bullmq';
import { Queue } from 'bullmq';
import { NotificationQueueJob } from '../interfaces/notification-queue.interface';
import { NotificationChannel } from '../entities/notification.entity';

@Injectable()
export class NotificationQueueService {
  private readonly logger = new Logger(NotificationQueueService.name);

  constructor(@InjectQueue('notification-queue') private readonly notificationQueue: Queue) {}

  async addNotification(job: NotificationQueueJob): Promise<void> {
    try {
      const jobId = job.idempotencyKey || `${job.restaurantId}-${job.notificationType}-${job.channel}-${Date.now()}`;

      await this.notificationQueue.add('send-notification', job, {
        jobId,
        attempts: 3,
        backoff: {
          type: 'exponential',
          delay: 2000,
        },
        removeOnComplete: {
          age: 24 * 3600, // Keep completed jobs for 24 hours
          count: 1000,
        },
        removeOnFail: {
          age: 7 * 24 * 3600, // Keep failed jobs for 7 days
        },
      });

      this.logger.log(`Notification job added to queue: ${jobId}`);
    } catch (error) {
      this.logger.error(`Failed to add notification to queue:`, error);
      throw error;
    }
  }

  async addBulkNotifications(jobs: NotificationQueueJob[]): Promise<void> {
    try {
      const queueJobs = jobs.map(job => ({
        name: 'send-notification',
        data: job,
        opts: {
          jobId: job.idempotencyKey || `${job.restaurantId}-${job.notificationType}-${job.channel}-${Date.now()}`,
          attempts: 3,
          backoff: {
            type: 'exponential',
            delay: 2000,
          },
        },
      }));

      await this.notificationQueue.addBulk(queueJobs);
      this.logger.log(`Added ${jobs.length} notification jobs to queue`);
    } catch (error) {
      this.logger.error(`Failed to add bulk notifications to queue:`, error);
      throw error;
    }
  }
}