package seatlist

import (
	"encoding/json"
	"testing"

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

type hubStub map[string]func(jetstream.Msg)

func (h hubStub) Handle(pattern string, f func(jetstream.Msg)) error { h[pattern] = f; return nil }

type msgStub struct {
	jetstream.Msg
	data  []byte
	acked *int
}

func (m msgStub) Data() []byte { return m.data }
func (m msgStub) Ack() error   { *m.acked++; return nil }

func TestAProcessBusAsksByKeyAndHearsTheSeatsEventsOnTheHub(t *testing.T) {
	var asked string
	hub := hubStub{}
	bus := ProcessBus(func(key string, body any) (json.RawMessage, error) { asked = key; return json.RawMessage(`{}`), nil }, hub)
	if _, err := bus.Ask(Key(), nil); err != nil || asked != Key() {
		t.Fatalf("asked %q, %v", asked, err)
	}
	var got []string
	if err := bus.Subscribe(Pattern(ChangedEvent), func(key string, body json.RawMessage) error { got = append(got, key+" "+string(body)); return nil }); err != nil {
		t.Fatal(err)
	}
	h := hub["mesh.seat."+Seat+".event."+ChangedEvent]
	if h == nil {
		t.Fatalf("handlers on %v, want the seat's own subject", hub)
	}
	acked := 0
	h(msgStub{data: []byte(`{"seat":"x"}`), acked: &acked})
	if len(got) != 1 || got[0] != Pattern(ChangedEvent)+` {"seat":"x"}` || acked != 1 {
		t.Errorf("heard %v, acked %d", got, acked)
	}
	if err := bus.Subscribe("nodot", nil); err == nil {
		t.Error("a pattern that names no seat event was taken")
	}
}