const (
	Pending status = iota
	Ready
	Stopped
)

const (

	// DefaultEventFreshDuration is the default time duration of events
	// we want to keep.
	// We set it to defaultBookmarkFrequency plus epsilon to maximize
	// chances that last bookmark was sent within kept history, at the
	// same time, minimizing the needed memory usage.
	DefaultEventFreshDuration = defaultBookmarkFrequency + 15*time.Second
)

var (
	// ConsistencyCheckPeriod is the period of checking consistency between etcd and cache.
	// 5 minutes were proposed to match the default compaction period. It's magnitute higher than
	// List latency SLO (30 seconds) and timeout (1 minute).
	ConsistencyCheckPeriod = 5 * time.Minute
	// ConsistencyCheckerEnabled enables the consistency checking mechanism for cache.
	// Based on KUBE_WATCHCACHE_CONSISTENCY_CHECKER environment variable.
	ConsistencyCheckerEnabled = false
)

type CacheDelegator struct {
	// contains filtered or unexported fields
}

type Cacher struct {
	sync.RWMutex
	// contains filtered or unexported fields
}

type Config struct {
	// An underlying storage.Interface.
	Storage storage.Interface

	// An underlying storage.Versioner.
	Versioner storage.Versioner

	// The GroupResource the cacher is caching. Used for disambiguating *unstructured.Unstructured (CRDs) in logging
	// and metrics.
	GroupResource schema.GroupResource

	// EventsHistoryWindow specifies minimum history duration that storage is keeping.
	// If lower than DefaultEventFreshDuration, the cache creation will fail.
	EventsHistoryWindow time.Duration

	// The Cache will be caching objects of a given Type and assumes that they
	// are all stored under ResourcePrefix directory in the underlying database.
	ResourcePrefix string

	// KeyFunc is used to get a key in the underlying storage for a given object.
	KeyFunc func(runtime.Object) (string, error)

	// GetAttrsFunc is used to get object labels, fields
	GetAttrsFunc func(runtime.Object) (label labels.Set, field fields.Set, err error)

	// IndexerFuncs is used for optimizing amount of watchers that
	// needs to process an incoming event.
	IndexerFuncs storage.IndexerFuncs

	// Indexers is used to accelerate the list operation, falls back to regular list
	// operation if no indexer found.
	Indexers *cache.Indexers

	// NewFunc is a function that creates new empty object storing a object of type Type.
	NewFunc func() runtime.Object

	// NewList is a function that creates new empty object storing a list of
	// objects of type Type.
	NewListFunc func() runtime.Object

	Codec runtime.Codec

	Clock clock.WithTicker
}

type Snapshotter interface {
	Reset()
	GetLessOrEqual(rv uint64) (orderedLister, bool)
	Add(rv uint64, indexer orderedLister)
	RemoveLess(rv uint64)
	Len() int
}