import type { CallHandler, ExecutionContext, NestInterceptor } from '@nestjs/common';
import { Injectable } from '@nestjs/common';
import type { FastifyReply } from 'fastify';
import type { Observable } from 'rxjs';
import { map } from 'rxjs/operators';
import { withResponseMeta } from '../core/http.js';

@Injectable()
export class ApiEnvelopeInterceptor implements NestInterceptor {
  intercept(context: ExecutionContext, next: CallHandler): Observable<unknown> {
    const reply = context.switchToHttp().getResponse<FastifyReply>();
    return next.handle().pipe(map(body => withResponseMeta(body, String(reply.getHeader('x-request-id') || ''))));
  }
}