//go:build integration

package process_test

import (
	"context"
	"testing"
	"time"

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

	"git.novox.be/novox/mesh-sdk/go/process"
	"git.novox.be/novox/mesh-sdk/go/testbus"
)

// A module whose consumer the bus makes after the module started is not lost for that order: the hub tries again after
// each wait and calls live once it is bound (the checker's "until it starts again" hole).
func TestTheHubBindsALateConsumerAndSaysItIsLive(t *testing.T) {
	nc, err := nats.Connect(testbus.URL(t))
	if err != nil {
		t.Fatal(err)
	}
	defer nc.Close()
	js, err := jetstream.New(nc)
	if err != nil {
		t.Fatal(err)
	}
	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
	defer cancel()
	if _, err := js.CreateStream(ctx, jetstream.StreamConfig{Name: process.EventsStream, Subjects: []string{"mesh.mod.*.event.>"}}); err != nil {
		t.Fatal(err)
	}
	cred := process.Account{Node: "n1", Module: "late"}
	hub := process.NewEventHub(t.Logf)
	waits, live := make(chan chan bool), make(chan struct{}, 1)
	wait := func(ctx context.Context) bool {
		step := make(chan bool)
		select {
		case waits <- step:
		case <-ctx.Done():
			return false
		}
		return <-step
	}
	if err := hub.StartUntilBound(ctx, js, cred, wait, func() { live <- struct{}{} }); err == nil {
		t.Fatal("no consumer was there, and the start said nothing")
	}
	select {
	case <-live:
		t.Fatal("live before the consumer was there")
	default:
	}
	step := <-waits
	step <- true // tried again: still no consumer
	step = <-waits
	if _, err := js.CreateOrUpdateConsumer(ctx, process.EventsStream, jetstream.ConsumerConfig{Durable: cred.EventConsumerName(), AckPolicy: jetstream.AckExplicitPolicy}); err != nil {
		t.Fatal(err)
	}
	step <- true
	select {
	case <-live:
	case <-ctx.Done():
		t.Fatal("the consumer was made and the hub never said it is live")
	}
	hub.Stop()
}