import {
  Injectable,
  NestInterceptor,
  ExecutionContext,
  CallHandler,
  HttpException,
} from '@nestjs/common';
import { Observable } from 'rxjs';
import { catchError } from 'rxjs/operators';
import { ApmService } from './apm.service';

@Injectable()
export class ApmInterceptor implements NestInterceptor {
  constructor(private readonly apmService: ApmService) {}

  intercept(
    context: ExecutionContext,
    next: CallHandler,
  ): Observable<Response> {
    const request = context.switchToHttp().getRequest<Request>();
    const user = request.headers['e-user'];
    const rules = request.headers['e-rules'];
    this.apmService.setCustomContext({ user, rules });

    return next.handle().pipe(
      catchError((error) => {
        if (error instanceof HttpException) {
          this.apmService.captureError(error.message);
        } else {
          this.apmService.captureError(error);
        }
        throw error;
      }),
    );
  }
}