import { Injectable, Logger } from '@nestjs/common';
import { PrismaService } from '../../infrastructure/database/prisma.service';
import { KnowledgeImportWorkflow } from '../ai/workflows/knowledge-import.workflow';
import type { KnowledgeGenerationSnapshot } from './knowledge-generation-snapshot-builder';

@Injectable()
export class KnowledgeGenerationExecutor {
  private readonly logger = new Logger(KnowledgeGenerationExecutor.name);

  constructor(
    private readonly prisma: PrismaService,
    private readonly workflow: KnowledgeImportWorkflow,
  ) {}

  async execute(snapshot: KnowledgeGenerationSnapshot, aiJobId: string) {
    const { taskId, sourceId, knowledgeBaseId, userId, rawText, sourceName } = snapshot.snapshot;

    const txOps = [
      this.prisma.knowledgeGenerationTask.updateMany({
        where: { id: taskId, aiJobId, status: { in: ['queued', 'running'] } },
        data: {
          status: 'running',
          startedAt: new Date(),
          errorCode: null,
          errorMessage: null,
        },
      }),
    ];
    if (sourceId) {
      txOps.push(
        this.prisma.knowledgeSource.updateMany({
          where: { id: sourceId, knowledgeBaseId, userId },
          data: { learningStatus: 'running' },
        }),
      );
    }
    await this.prisma.$transaction(txOps);

    const result = await this.workflow.execute({
      userId,
      rawText,
      sourceName,
    });

    this.logger.log(
      `Knowledge Generation Executor completed: job=${aiJobId} ` +
      `task=${taskId} source=${sourceId ?? 'n/a'} points=${result.knowledgePoints?.length ?? 0}`,
    );

    return { parsed: result };
  }
}