package slack_test

import (
	"context"
	"testing"

	"atlas9.dev/c/core"
	"atlas9.dev/c/core/assert"
	"atlas9.dev/c/demo/lib/slack"
)

// fakeStore returns a fixed set of endpoints for ListActiveForEvent; the other
// Store methods are unused by Fanout and panic if called.
type fakeStore struct {
	eps []slack.Endpoint
}

func (f fakeStore) ListActiveForEvent(ctx context.Context, tenant core.ID, eventType string) ([]slack.Endpoint, error) {
	return f.eps, nil
}

func (fakeStore) CreateEndpoint(context.Context, *slack.Endpoint) error { panic("unused") }
func (fakeStore) UpdateEndpoint(context.Context, *slack.Endpoint) error { panic("unused") }
func (fakeStore) GetEndpoint(context.Context, core.ID, core.ID, *slack.Endpoint) error {
	panic("unused")
}
func (fakeStore) ListEndpoints(context.Context, core.ID, core.PageReq, *core.Page[slack.Endpoint]) error {
	panic("unused")
}
func (fakeStore) DeleteEndpoint(context.Context, core.ID, core.ID) error { panic("unused") }

type fakeQueue struct {
	deliveries []slack.Delivery
}

func (q *fakeQueue) Create(ctx context.Context, d slack.Delivery) error {

	q.deliveries = append(q.deliveries, d)
	return nil
}

func TestFanout_Emit_WrapsTextAndEnqueuesPerEndpoint(t *testing.T) {

	tenant := core.NewID("t")
	eps := []slack.Endpoint{
		{ID: core.NewID("slk"), Tenant: tenant, Name: "a"},
		{ID: core.NewID("slk"), Tenant: tenant, Name: "b"},
	}
	q := &fakeQueue{}
	f := slack.Fanout{Endpoints: fakeStore{eps: eps}, Deliveries: q}

	err := f.Emit(context.Background(), tenant, "Todos_ItemCreated", slack.Message{Text: "hello world"})
	assert.Ok(t, err)

	// One delivery per subscribed endpoint, each carrying the Slack envelope.
	assert.Eq(t, len(q.deliveries), 2)
	assert.Eq(t, string(q.deliveries[0].Body), `{"text":"hello world"}`)
	assert.Eq(t, q.deliveries[0].Endpoint, eps[0].ID)
	assert.Eq(t, q.deliveries[1].Endpoint, eps[1].ID)
	assert.Eq(t, q.deliveries[0].Type, "Todos_ItemCreated")
}

// With no subscribers there is nothing to marshal or enqueue.
func TestFanout_Emit_NoSubscribers(t *testing.T) {

	q := &fakeQueue{}
	f := slack.Fanout{Endpoints: fakeStore{eps: nil}, Deliveries: q}

	err := f.Emit(context.Background(), core.NewID("t"), "Todos_ItemCreated", slack.Message{Text: "hello"})
	assert.Ok(t, err)
	assert.Eq(t, len(q.deliveries), 0)
}