package services

import (
	"context"
	"testing"

	"github.com/google/uuid"
	"github.com/stretchr/testify/assert"
	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
	"go.uber.org/zap/zaptest/observer"
)

func TestChatPubSubService_NilRedisLogsError(t *testing.T) {
	core, observed := observer.New(zapcore.ErrorLevel)
	logger := zap.New(core)

	_ = NewChatPubSubService(nil, logger)

	entries := observed.All()
	assert.Len(t, entries, 1, "constructor should emit exactly one ERROR log when Redis is nil")
	assert.Equal(t, zapcore.ErrorLevel, entries[0].Level)
	assert.Contains(t, entries[0].Message, "cross-instance messages will be lost")
}

func TestChatPubSubService_InMemoryFanout(t *testing.T) {
	svc := NewChatPubSubService(nil, zap.NewNop())

	ctx := context.Background()
	roomID := uuid.New()

	ch, cancel, err := svc.Subscribe(ctx, roomID)
	assert.NoError(t, err)
	defer cancel()

	err = svc.Publish(ctx, roomID, []byte("hello"))
	assert.NoError(t, err)

	select {
	case msg := <-ch:
		assert.Equal(t, "hello", string(msg))
	default:
		t.Fatal("expected message on in-memory channel")
	}
}