/*
 * @author gs
 * @date 2020/07/27 16:13
 */

import {
  CallHandler,
  ExecutionContext,
  Injectable,
  NestInterceptor
} from '@nestjs/common';
import { map } from 'rxjs/operators';
import { Observable } from 'rxjs';
import { GqlContextType } from '@nestjs/graphql';

interface Response<T> {
  data: T;
  code?: number;
}

@Injectable()
export class ResponseInterceptor<T> implements NestInterceptor<T, Response<T>> {
  intercept(
    context: ExecutionContext,
    next: CallHandler
  ): Observable<Response<T>> {
    return context.getType<GqlContextType>() === 'graphql'
      ? next.handle().pipe(map(data => data))
      : next.handle().pipe(map(data => ({ data, code: 0 })));
  }
}