import { BadRequestException, Injectable } from '@nestjs/common';
import { ModuleRef } from '@nestjs/core';
import { DataSource, Repository } from 'typeorm';
import { getRepositoryToken } from '@nestjs/typeorm';
import { ConfigService } from '@nestjs/config';

@Injectable()
export class ReflectionHelper {
  schema: string;
  constructor(
    private moduleRef: ModuleRef,
    private dataSource: DataSource,
    private readonly configService: ConfigService
  ) {
    this.schema = this.configService.get('DB_SCHEMA') || 'default';
  }

  getRepoService(entityName: string): Repository<any> {
    const entityMetadata: any = this.dataSource.entityMetadatas.find(
      (meta) =>
        meta.name === entityName ||
        (meta.target && (meta.target as any).name === entityName),
    );

    if (!entityMetadata) {
      console.error(`Entity "${entityName}" not found in TypeORM metadata`);
      throw new BadRequestException();
    }

    try {
      return this.moduleRef.get<Repository<any>>(
        getRepositoryToken(entityMetadata.target),
        { strict: false },
      );
    } catch (error) {
      console.error(`Repository for "${entityName}" not found:`, error.message);
      throw new BadRequestException();
    }
  }

  async getBean<T>(beanName: string): Promise<T | null> {
    try {
      const provider = this.moduleRef.get<T>(beanName as any, {
        strict: false,
      });

      if (!provider) {
        console.error(`Bean "${beanName}" not found in moduleRef.`);
        return null;
      }

      return provider;
    } catch (error) {
      console.error(`Bean "${beanName}" not found:`, error.message);
      return null;
    }
  }

  async getEntityData(id: number, tableName: string) {
    const entityList = await this.dataSource.query(`SELECT *
                                                    FROM ${this.schema}.${tableName}
                                                    WHERE id = $1`, [id]);

    return entityList.length > 0 ? entityList[0] : null;
  }
}