segment

type Automaton interface {

	// Start returns the start state
	Start() int

	// IsMatch returns true if and only if the state is a match
	IsMatch(int) bool

	// CanMatch returns true if and only if it is possible to reach a match
	// in zero or more steps
	CanMatch(int) bool

	// WillAlwaysMatch returns true if and only if the current state matches
	// and will always match no matter what steps are taken
	WillAlwaysMatch(int) bool

	// Accept returns the next state given the input to the specified state
	Accept(int, byte) int
}

type CollectionStats interface {

	// TotalDocumentCount returns the number of documents, regardless of whether or not
	// they have any terms for this field
	TotalDocumentCount() uint64

	// DocumentCount returns the number of documents with at least one term for this field
	DocumentCount() uint64

	// SumTotalTermFrequency returns to total number of tokens across all documents
	SumTotalTermFrequency() uint64

	Merge(CollectionStats)
}

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

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

type Dictionary interface {
	DictionaryLookup

	PostingsList(term []byte, except *roaring.Bitmap, prealloc PostingsList) (PostingsList, error)

	Iterator(a Automaton,
		startKeyInclusive, endKeyExclusive []byte) DictionaryIterator
}

type DictionaryEntry interface {
	Term() string
	Count() uint64
}

type DictionaryIterator interface {
	Next() (DictionaryEntry, error)
	Close() error
}

type DictionaryLookup interface {
	Contains(key []byte) (bool, error)
	Close() error
}

type DocVisitState interface {
}

type Document interface {
	Analyze()
	EachField(vf VisitField)
	Timestamp() int64
}

type DocumentValueReader interface {
	VisitDocumentValues(number uint64, visitor DocumentValueVisitor) error
}

type DocumentValueVisitor func(field string, term []byte)

type Field interface {
	Name() string
	Length() int
	EachTerm(vt VisitTerm)
	Value() []byte

	Index() bool
	Store() bool
	IndexDocValues() bool
}

type FieldTerm interface {
	Term() []byte
	Frequency() int
	EachLocation(vl VisitLocation)
}

type Location interface {
	Field() string
	Start() int
	End() int
	Pos() int
	Size() int
}

type Merger interface {
	WriteTo(w io.Writer, closeCh chan struct{}) (n int64, err error)
	DocumentNumbers() [][]uint64
}

type Optimizable interface {
	Optimize(kind string, octx OptimizableContext) (OptimizableContext, error)
}

type OptimizableContext interface {
	// Once all the optimzable resources have been provided the same
	// OptimizableContext instance, the optimization preparations are
	// finished or completed via the Finish() method.
	//
	// Depending on the optimization being performed, the Finish()
	// method might return a non-nil Optimized instance.  For example,
	// the Optimized instance might represent an optimized
	// PostingsIterator instance.
	Finish() (PostingsIterator, error)
}

type OptimizablePostingsIterator interface {
	ActualBitmap() *roaring.Bitmap
	DocNum1Hit() (uint64, bool)
	ReplaceActual(*roaring.Bitmap)
}

type Posting interface {
	Number() uint64
	SetNumber(uint64)
	Frequency() int
	Norm() float64
	Locations() []Location
	Size() int
}

type PostingsIterator interface {
	// The caller is responsible for copying whatever it needs from
	// the returned Posting instance before calling Next(), as some
	// implementations may return a shared instance to reduce memory
	// allocations.
	Next() (Posting, error)

	// Advance will return the posting with the specified doc number
	// or if there is no such posting, the next posting.
	// Callers MUST NOT attempt to pass a docNum that is less than or
	// equal to the currently visited posting doc Num.
	Advance(docNum uint64) (Posting, error)

	Size() int

	// is this postings iterator empty?
	Empty() bool

	Count() uint64

	Close() error
}

type PostingsList interface {
	Iterator(includeFreq, includeNorm, includeLocations bool, prealloc PostingsIterator) (PostingsIterator, error)

	Size() int

	Count() uint64
}

type Segment interface {
	Dictionary(field string) (Dictionary, error)

	VisitStoredFields(num uint64, visitor StoredFieldVisitor) error

	Count() uint64

	DocsMatchingTerms([]Term) (*roaring.Bitmap, error)

	Fields() []string

	CollectionStats(field string) (CollectionStats, error)

	Size() int

	DocumentValueReader(fields []string) (DocumentValueReader, error)

	WriteTo(w io.Writer, closeCh chan struct{}) (int64, error)

	Type() string
	Version() uint32

	Timestamp() (int64, int64)
}

type StoredFieldVisitor func(field string, value []byte) bool

type Term interface {
	Field() string
	Term() []byte
}

type TermStats interface {

	// DocumentFrequency returns the number of documents using this term
	DocumentFrequency() uint64
}

type VisitField func(Field)

type VisitLocation func(Location)

type VisitTerm func(FieldTerm)