import { Injectable, NotFoundException } from '@nestjs/common';
import { ImportCandidateRepository } from './import-candidate.repository';
import { KnowledgeItemsRepository } from '../knowledge-items/knowledge-items.repository';

@Injectable()
export class ImportCandidateService {
  constructor(
    private readonly repository: ImportCandidateRepository,
    private readonly itemsRepo: KnowledgeItemsRepository,
  ) {}

  async findBySource(sourceId: string) {
    return this.repository.findBySource(sourceId);
  }

  async findOne(id: string) {
    const c = await this.repository.findById(id);
    if (!c) throw new NotFoundException('候选知识点不存在');
    return c;
  }

  async accept(id: string) {
    const candidate = await this.repository.findById(id);
    if (!candidate) throw new NotFoundException('候选知识点不存在');

    await this.repository.updateStatus(id, 'ACCEPTED');

    // 生成 KnowledgeItem
    await this.itemsRepo.create(candidate.userId, candidate.knowledgeBaseId, {
      title: candidate.title,
      content: (candidate.content as string) ?? '',
      itemType: 'ai_generated',
      orderIndex: candidate.orderIndex,
    });

    return { status: 'ACCEPTED' };
  }

  async reject(id: string) {
    const candidate = await this.repository.findById(id);
    if (!candidate) throw new NotFoundException('候选知识点不存在');
    return this.repository.updateStatus(id, 'REJECTED');
  }

  async batchAccept(sourceId: string) {
    const candidates = await this.repository.findBySource(sourceId);
    const pending = candidates.filter(c => c.status === 'PENDING');

    for (const c of pending) {
      await this.accept(c.id);
    }

    return { accepted: pending.length };
  }

  async update(id: string, dto: any) {
    const candidate = await this.repository.findById(id);
    if (!candidate) throw new NotFoundException('候选知识点不存在');
    return this.repository.update(id, dto);
  }

  async createCandidates(userId: string, knowledgeBaseId: string, sourceId: string, importId: string, candidates: Array<any>) {
    return this.repository.createMany(userId, knowledgeBaseId, sourceId, importId, candidates);
  }
}