import { ArgumentsHost, Catch } from "@nestjs/common";
import { QueryFailedError } from "typeorm";
import { TypeORMError } from "typeorm/error/TypeORMError";

/**
 * Exception filter to handle database errors and transform them into HTTP responses.
 * This filter catches TypeORM errors and returns a 502 Bad Gateway response with the error message.
 */
@Catch(TypeORMError)
export class DbExceptionFilter implements DbExceptionFilter {
  catch(exception: QueryFailedError, host: ArgumentsHost) {
    const response = host.switchToHttp().getResponse();
    response.status(502).json({ message: exception.message });
  }
}