// QueueStore - Filestore for persisting items.
type QueueStore[_ any] struct {
	sync.RWMutex
	entryLimit uint64
	directory  string
	fileExt    string

	entries map[string]int64 // key -> modtime as unix nano
}

// NewQueueStore - Creates an instance for QueueStore.
func NewQueueStore[I any](directory string, limit uint64, ext string) *QueueStore[I] {
	if limit == 0 {
		limit = defaultLimit

	testItemExt = ".test"
)

// Initialize the queue store.
func setUpQueueStore(directory string, limit uint64) (Store[TestItem], error) {
	queueStore := NewQueueStore[TestItem](queueDir, limit, testItemExt)
	if oErr := queueStore.Open(); oErr != nil {
		return nil, oErr
	}
	return queueStore, nil
}

// Tear down queue store.
func tearDownQueueStore() error {
	return os.RemoveAll(queueDir)
}

func NewNSQTarget(id string, args NSQArgs, loggerOnce logger.LogOnce) (*NSQTarget, error) {
	var queueStore store.Store[event.Event]
	if args.QueueDir != "" {
		queueDir := filepath.Join(args.QueueDir, storePrefix+"-nsq-"+id)
		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {

func NewRedisTarget(id string, args RedisArgs, loggerOnce logger.LogOnce) (*RedisTarget, error) {
	var queueStore store.Store[event.Event]
	if args.QueueDir != "" {
		queueDir := filepath.Join(args.QueueDir, storePrefix+"-redis-"+id)
		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {

	ctx, cancel := context.WithCancel(ctx)

	var queueStore store.Store[event.Event]
	if args.QueueDir != "" {
		queueDir := filepath.Join(args.QueueDir, storePrefix+"-webhook-"+id)
		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {
			cancel()

	var queueStore store.Store[event.Event]
	if args.QueueDir != "" {
		queueDir := filepath.Join(args.QueueDir, storePrefix+"-elasticsearch-"+id)
		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {

	}

	if args.KeepAlive == 0 {
		args.KeepAlive = 10 * time.Second
	}

	var queueStore store.Store[event.Event]
	if args.QueueDir != "" {
		queueDir := filepath.Join(args.QueueDir, storePrefix+"-mqtt-"+id)
		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {

	return nil
}

func (h *Target) initQueueStore(ctx context.Context) (err error) {
	var queueStore store.Store[interface{}]
	queueDir := filepath.Join(h.kconfig.QueueDir, h.Name())
	queueStore = store.NewQueueStore[interface{}](queueDir, uint64(h.kconfig.QueueSize), kafkaLoggerExtension)
	if err = queueStore.Open(); err != nil {
		return fmt.Errorf("unable to initialize the queue store of %s webhook: %w", h.Name(), err)
	}

func NewMySQLTarget(id string, args MySQLArgs, loggerOnce logger.LogOnce) (*MySQLTarget, error) {
	var queueStore store.Store[event.Event]
	if args.QueueDir != "" {
		queueDir := filepath.Join(args.QueueDir, storePrefix+"-mysql-"+id)
		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {

func NewKafkaTarget(id string, args KafkaArgs, loggerOnce logger.LogOnce) (*KafkaTarget, error) {
	var queueStore store.Store[event.Event]
	if args.QueueDir != "" {
		queueDir := filepath.Join(args.QueueDir, storePrefix+"-kafka-"+id)
		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {