import {
  Inject,
  Injectable,
  Logger,
  type OnModuleInit,
  type OnModuleDestroy,
} from '@nestjs/common';
import cron from 'node-cron';
import { SummarizationService } from './summarization.service.js';

@Injectable()
export class CronService implements OnModuleInit, OnModuleDestroy {
  private readonly logger = new Logger(CronService.name);
  private readonly tasks: cron.ScheduledTask[] = [];

  constructor(@Inject(SummarizationService) private readonly summarization: SummarizationService) {}

  onModuleInit(): void {
    const summarizationSchedule = process.env['SUMMARIZATION_CRON'] ?? '0 */6 * * *'; // every 6 hours
    const tierManagementSchedule = process.env['TIER_MANAGEMENT_CRON'] ?? '0 3 * * *'; // daily at 3am

    this.tasks.push(
      cron.schedule(summarizationSchedule, () => {
        this.summarization.runSummarization().catch((err) => {
          this.logger.error(`Scheduled summarization failed: ${err}`);
        });
      }),
    );

    this.tasks.push(
      cron.schedule(tierManagementSchedule, () => {
        this.summarization.runTierManagement().catch((err) => {
          this.logger.error(`Scheduled tier management failed: ${err}`);
        });
      }),
    );

    this.logger.log(
      `Cron scheduled: summarization="${summarizationSchedule}", tier="${tierManagementSchedule}"`,
    );
  }

  onModuleDestroy(): void {
    for (const task of this.tasks) {
      task.stop();
    }
    this.tasks.length = 0;
    this.logger.log('Cron tasks stopped');
  }
}