import { Injectable } from '@nestjs/common';
import { DocumentImportRepository } from './document-import.repository';
import { RedisService } from '../../infrastructure/redis/redis.service';
import { QueueService } from '../../infrastructure/queue/queue.service';

@Injectable()
export class DocumentImportService {
  constructor(
    private readonly repository: DocumentImportRepository,
    private readonly redis: RedisService,
    private readonly queue: QueueService,
  ) {}

  async createImport(dto: {
    userId?: string;
    knowledgeBaseId?: string;
    fileName?: string;
    sourceType?: string;
    rawText?: string;
  }) {
    const lockKey = `lock:document-import:${dto.fileName || Date.now()}`;
    const lockToken = await this.redis.lock(lockKey, 1800);
    if (!lockToken) {
      throw new Error('相同文件正在导入中，请稍候');
    }

    const job = await this.repository.create(dto);

    await this.redis.set(`job:document-import:${job.id}:status`, 'pending', 86400);
    await this.redis.set(`job:document-import:${job.id}:progress`, '0', 86400);
    await this.redis.set(`job:document-import:${job.id}:message`, '任务已加入队列', 86400);

    await this.queue.add('document-import', {
      importId: job.id,
      userId: dto.userId || 'anonymous',
      knowledgeBaseId: dto.knowledgeBaseId,
      rawText: dto.rawText,
      fileName: dto.fileName,
    });

    // Release the lock — the worker will re-lock if needed
    await this.redis.unlock(lockKey, lockToken);

    return { jobId: job.id, status: 'queued' };
  }

  async getStatus(id: string) {
    const redisStatus = await this.redis.get(`job:document-import:${id}:status`);
    const redisProgress = await this.redis.get(`job:document-import:${id}:progress`);
    const redisMessage = await this.redis.get(`job:document-import:${id}:message`);
    const dbJob = await this.repository.findById(id);

    return {
      id,
      fileName: dbJob?.sourceName,
      status: redisStatus || dbJob?.status || 'unknown',
      progress: redisProgress ? parseInt(redisProgress, 10) : 0,
      message: redisMessage || null,
    };
  }
}