import { Injectable, OnModuleInit } from '@nestjs/common';
import { Cron, CronExpression } from '@nestjs/schedule';
import { HandleExpiredItemsCommand } from '../../application/commands/handle-expired-items.command';
import { LoggerService } from '../../application/services/logger.service';

@Injectable()
export class ExpiredItemsSchedulerService implements OnModuleInit {
  constructor(
    private readonly handleExpiredItemsCommand: HandleExpiredItemsCommand,
    private readonly logger: LoggerService,
  ) {}

  async onModuleInit(): Promise<void> {
    this.logger.log('ExpiredItemsSchedulerService initialized', ExpiredItemsSchedulerService.name);

    // Process expired items immediately on startup
    try {
      this.logger.log('Processing expired items on startup...', ExpiredItemsSchedulerService.name);
      await this.handleExpiredItemsCommand.execute();
      this.logger.log('Startup expired items processing completed', ExpiredItemsSchedulerService.name);
    } catch (error) {
      this.logger.error(`Failed to process expired items on startup: ${error.message}`, undefined, ExpiredItemsSchedulerService.name);
    }
  }

  @Cron(CronExpression.EVERY_MINUTE)
  async handleExpiredItemsCron(): Promise<void> {
    try {
      this.logger.log('Starting scheduled expired items processing', ExpiredItemsSchedulerService.name);
      await this.handleExpiredItemsCommand.execute();
      this.logger.log('Scheduled expired items processing completed', ExpiredItemsSchedulerService.name);
    } catch (error) {
      this.logger.error(`Failed to process expired items: ${error.message}`, undefined, ExpiredItemsSchedulerService.name);
      // Continue running despite errors - don't let one failure stop the scheduler
    }
  }

  @Cron('0 0 * * *') // Every day at midnight
  async handleExpiredItemsDaily(): Promise<void> {
    try {
      this.logger.log('Starting daily expired items processing at midnight', ExpiredItemsSchedulerService.name);
      await this.handleExpiredItemsCommand.execute();
      this.logger.log('Daily expired items processing completed', ExpiredItemsSchedulerService.name);
    } catch (error) {
      this.logger.error(`Failed to process expired items at midnight: ${error.message}`, undefined, ExpiredItemsSchedulerService.name);
    }
  }
}