package process

import (
	"reflect"
	"testing"

	"github.com/nats-io/nats.go"
)

// 1171/AC3: it offers no Serve and no way to serve a tool — a process reaches the bus only as itself, and
// never answers a call. Checked by reflection over *Conn's whole method set and field list, so a later
// addition cannot bring one back without this test naming it.
func TestConnOffersNoServeAndExposesNoRawConnection(t *testing.T) {
	ptrType := reflect.TypeOf(&Conn{})
	for _, forbidden := range []string{"Serve", "ServeOn", "Handle", "Subscribe", "Respond", "Answer"} {
		if _, ok := ptrType.MethodByName(forbidden); ok {
			t.Errorf("*Conn has a method %s: a process offers no way to serve a tool", forbidden)
		}
	}

	natsConnType := reflect.TypeOf(&nats.Conn{})
	structType := reflect.TypeOf(Conn{})
	for i := 0; i < structType.NumField(); i++ {
		f := structType.Field(i)
		if f.IsExported() && (f.Type == natsConnType || f.Type == natsConnType.Elem()) {
			t.Errorf("Conn exposes its raw connection through the exported field %s", f.Name)
		}
	}
	for i := 0; i < ptrType.NumMethod(); i++ {
		m := ptrType.Method(i)
		for o := 0; o < m.Type.NumOut(); o++ {
			if m.Type.Out(o) == natsConnType || m.Type.Out(o) == natsConnType.Elem() {
				t.Errorf("*Conn.%s returns the raw *nats.Conn", m.Name)
			}
		}
	}
}