import { Module, Global } from '@nestjs/common';
import { BullModule } from '@nestjs/bullmq';
import { ConfigModule, ConfigService } from '@nestjs/config';

/**
 * 队列模块 - 基础设施层
 * 基于 NestJS 官方文档实现
 * 参考: https://docs.nestjs.cn/techniques/queues
 * 使用 BullMQ 作为队列引擎
 */
@Global()
@Module({
  imports: [
    BullModule.forRootAsync({
      imports: [ConfigModule],
      inject: [ConfigService],
      useFactory: async (configService: ConfigService) => {
        const redisConfig = configService.get('redis');

        return {
          connection: {
            host: redisConfig.host,
            port: redisConfig.port,
            password: redisConfig.password,
            db: redisConfig.db,
          },
          defaultJobOptions: {
            removeOnComplete: 10,
            removeOnFail: 5,
            attempts: 3,
            backoff: {
              type: 'exponential',
              delay: 2000,
            },
          },
        };
      },
    }),
  ],
  exports: [BullModule],
})
export class QueueModule {}