import { Injectable } from '@nestjs/common';
import { DataSource } from 'typeorm';
import { SQL_PROCEDURES_PATH } from '@app/common/constants/sql-query-path';
import { SqlLoaderService } from './sql-loader.service';

@Injectable()
export class OccupancyService {
  constructor(
    private readonly sqlLoader: SqlLoaderService,
    private readonly dataSource: DataSource,
  ) {}

  async updateOccupancyDataProcedures(): Promise<void> {
    try {
      const { dateStr } = this.getFormattedDates();

      // Execute all procedures in parallel
      await Promise.all([
        this.executeProcedureWithRetry(
          'procedure_update_fact_space_occupancy',
          [dateStr],
          'fact_space_occupancy_count',
        ),
        this.executeProcedureWithRetry(
          'procedure_update_daily_space_occupancy_duration',
          [dateStr],
          'fact_daily_space_occupancy_duration',
        ),
      ]);
    } catch (err) {
      console.error('Failed to update occupancy data:', err);
      throw err;
    }
  }
  private getFormattedDates(): { dateStr: string } {
    const now = new Date();
    return {
      dateStr: now.toLocaleDateString('en-CA'), // YYYY-MM-DD
    };
  }
  private async executeProcedureWithRetry(
    procedureFileName: string,
    params: (string | number | null)[],
    folderName: string,
    retries = 3,
  ): Promise<void> {
    try {
      const query = this.loadQuery(folderName, procedureFileName);
      await this.dataSource.query(query, params);
      console.log(`Procedure ${procedureFileName} executed successfully.`);
    } catch (err) {
      if (retries > 0) {
        const delayMs = 1000 * (4 - retries); // Exponential backoff
        console.warn(`Retrying ${procedureFileName} (${retries} retries left)`);
        await new Promise((resolve) => setTimeout(resolve, delayMs));
        return this.executeProcedureWithRetry(
          procedureFileName,
          params,
          folderName,
          retries - 1,
        );
      }
      console.error(`Failed to execute ${procedureFileName}:`, err);
      throw err;
    }
  }

  private loadQuery(folderName: string, fileName: string): string {
    return this.sqlLoader.loadQuery(folderName, fileName, SQL_PROCEDURES_PATH);
  }
}