"strings"
)

const (
	document = "document"
	lines    = "lines"

	defaultRecordDelimiter = "\n"
)

// ReaderArgs - represents elements inside <InputSerialization><JSON/> in request XML.
type ReaderArgs struct {
	ContentType string `xml:"Type"`
	unmarshaled bool
}

// IsEmpty - returns whether reader args is empty or not.
func (args *ReaderArgs) IsEmpty() bool {
	return !args.unmarshaled
}

	"net/http/httptrace"
	"sync/atomic"
	"time"
)

var globalStats = struct {
	errs uint64

	tcpDialErrs                 uint64
	tcpDialCount                uint64
	tcpDialTotalDur             uint64
	tcpTimeForFirstByteTotalDur uint64
}{}

// RPCStats holds information about the DHCP/TCP metrics and errors
type RPCStats struct {
	Errs uint64

	DialAvgDuration uint64
	TTFBAvgDuration uint64

// and format-xl.go for details.

// Ideally we will never have a situation where we will have to change the
// fields of this struct and deal with related migration.
type formatMetaV1 struct {
	// Version of the format config.
	Version string `json:"version"`
	// Format indicates the backend format type, supports two values 'xl' and 'fs'.
	Format string `json:"format"`

	storageRESTOrigVolume       = "ovol"
	storageRESTInclFreeVersions = "incl-fv"
	storageRESTRange            = "rng"
)

type nsScannerOptions struct {
	DiskID   string          `msg:"id"`
	ScanMode int             `msg:"m"`
	Cache    *dataUsageCache `msg:"c"`
}

type nsScannerResp struct {
	Update *dataUsageEntry `msg:"u"`
	Final  *dataUsageCache `msg:"f"`

// TargetIDSet - Set representation of TargetIDs.
type TargetIDSet map[TargetID]struct{}

// Clone - returns copy of this set.
func (set TargetIDSet) Clone() TargetIDSet {
	setCopy := NewTargetIDSet()
	maps.Copy(setCopy, set)
	return setCopy
}

// add - adds TargetID to the set.
func (set TargetIDSet) add(targetID TargetID) {
	set[targetID] = struct{}{}
}

// Union - returns union with given set as new set.

// LRU implements a thread-safe LRU with expirable entries.
type LRU[K comparable, V any] struct {
	size      int
	evictList *LruList[K, V]
	items     map[K]*Entry[K, V]
	onEvict   EvictCallback[K, V]

	// expirable options
	mu   sync.RWMutex
	ttl  time.Duration
	done chan struct{}

	// buckets for expiration
	buckets []bucket[K, V]
	// uint8 because it's number between 0 and numBuckets

 */

 */

 */

// Stats is a collection of stats for multiple targets.
type Stats struct {
	TotalEvents        int64 // Deprecated
	EventsSkipped      int64
	CurrentQueuedCalls int64 // Deprecated
	EventsErrorsTotal  int64 // Deprecated
	CurrentSendCalls   int64 // Deprecated

	TargetStats map[TargetID]TargetStat
}

// TargetStat is the stats of a single target.
type TargetStat struct {