import { Injectable, Logger, OnModuleInit } from '@nestjs/common';
import { KafkaService } from '../../infrastructure';
import { EventAckPublisher } from '../../infrastructure/kafka/event-ack.publisher';
import { TeamStatisticsService } from '../services';
import { UpdateTeamStatisticsCommand } from '../commands';

interface PlantingCreatedEvent {
  eventName: string;
  data: {
    userId: string;
    treeCount: number;
    provinceCode: string;
    cityCode: string;
  };
  _outbox?: {
    id: string;
    aggregateId: string;
    eventType: string;
  };
}

/**
 * 认种创建事件处理器
 * 监听 planting-service 发出的认种事件
 */
@Injectable()
export class PlantingCreatedHandler implements OnModuleInit {
  private readonly logger = new Logger(PlantingCreatedHandler.name);

  constructor(
    private readonly kafkaService: KafkaService,
    private readonly teamStatisticsService: TeamStatisticsService,
    private readonly eventAckPublisher: EventAckPublisher,
  ) {}

  async onModuleInit() {
    await this.kafkaService.subscribe(
      'referral-service-planting-created',
      ['planting.planting.created'],
      this.handleMessage.bind(this),
    );
    this.logger.log('Subscribed to planting.created events');
  }

  private async handleMessage(topic: string, message: Record<string, unknown>): Promise<void> {
    const event = message as unknown as PlantingCreatedEvent;

    if (event.eventName !== 'planting.created') {
      return;
    }

    // B方案：提取 outbox 信息用于发送确认
    const outboxInfo = event._outbox;
    const eventId = outboxInfo?.aggregateId || 'unknown';

    try {
      const command = new UpdateTeamStatisticsCommand(
        BigInt(event.data.userId),
        event.data.treeCount,
        event.data.provinceCode,
        event.data.cityCode,
      );

      await this.teamStatisticsService.handlePlantingEvent(command);
      this.logger.log(
        `Updated team statistics for user ${event.data.userId}, count: ${event.data.treeCount}`,
      );

      // B方案：发送处理成功确认
      if (outboxInfo) {
        await this.eventAckPublisher.sendSuccess(eventId, outboxInfo.eventType);
      }
    } catch (error) {
      this.logger.error(
        `Failed to update team statistics for user ${event.data.userId}:`,
        error,
      );

      // B方案：发送处理失败确认
      if (outboxInfo) {
        const errorMessage = error instanceof Error ? error.message : String(error);
        await this.eventAckPublisher.sendFailure(eventId, outboxInfo.eventType, errorMessage);
      }
    }
  }
}