package events

import (
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
)

func TestBroker_DeliversToAllSubscribers(t *testing.T) {
	b := NewBroker()
	a, cancelA := b.Subscribe()
	defer cancelA()
	c, cancelC := b.Subscribe()
	defer cancelC()

	b.Publish(Services)
	assert.Equal(t, Services, <-a)
	assert.Equal(t, Services, <-c)
}

func TestBroker_CancelStopsDelivery(t *testing.T) {
	b := NewBroker()
	ch, cancel := b.Subscribe()
	cancel()
	cancel() // safe to call twice
	b.Publish(Agents)
	assert.Empty(t, ch)
}

func TestBroker_SlowSubscriberDoesNotBlockPublish(t *testing.T) {
	b := NewBroker()
	_, cancel := b.Subscribe()
	defer cancel()

	done := make(chan struct{})
	go func() {
		defer close(done)
		for range 1000 {
			b.Publish(Services) // must return even though nobody reads
		}
	}()
	select {
	case <-done:
	case <-time.After(time.Second):
		t.Fatal("Publish blocked on a slow subscriber")
	}
}

func TestJobTopic(t *testing.T) {
	assert.Equal(t, Topic("job-42"), JobTopic(42))
}