import { BullModuleOptions, SharedBullConfigurationFactory } from '@nestjs/bull';
import { Injectable } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';

/**
 * Bull Queue Configuration
 * Configures Redis connection and queue settings for Bull
 */
@Injectable()
export class BullConfigService implements SharedBullConfigurationFactory {
  constructor(private configService: ConfigService) {}

  createSharedConfiguration(): BullModuleOptions {
    return {
      redis: {
        host: '43.205.35.45',
        port: 6379,
        password: 'Rezolut123',
        db: 0,
        // Enable offline queue to handle Redis disconnections
        enableOfflineQueue: true,
        // Retry strategy for Redis connection
        retryStrategy: (times: number) => {
          const delay = Math.min(times * 50, 2000);
          return delay;
        },
        // Connection timeout
        connectTimeout: 10000,
        // Keep alive settings
        keepAlive: 30000,
      },
      // Default job options for all queues
      defaultJobOptions: {
        attempts: 3,
        backoff: {
          type: 'exponential',
          delay: 5000,
        },
        removeOnComplete: {
          age: 3600 * 24 * 7, // Keep completed jobs for 7 days
          count: 1000, // Keep max 1000 completed jobs
        },
        removeOnFail: {
          age: 3600 * 24 * 30, // Keep failed jobs for 30 days
        },
      },
      // Queue settings
      settings: {
        // Stalled job checking interval
        stalledInterval: 30000,
        // Maximum stalled count before job is considered failed
        maxStalledCount: 2,
        // Lock duration for jobs
        lockDuration: 300000, // 5 minutes
        // Lock renew time
        lockRenewTime: 150000, // 2.5 minutes
      },
      // Prefix for all queue keys in Redis
      prefix: 'bull',
    };
  }
}

/**
 * Factory function for BullModule.forRootAsync()
 */
export const bullConfigFactory = {
  useClass: BullConfigService,
};