const (
	// MaxPointsPerBlock is the maximum number of points in an encoded
	// block in a TSM file. It should match the value in the tsm1
	// package, but we don't want to import it.
	MaxPointsPerBlock = 1000
)

var (
	// nil sorts lowest
	NilSortLo = []byte{0x00}
	// nil sorts highest
	NilSortHi = []byte{0xff}
)

var BooleanEmptyArrayCursor cursors.BooleanArrayCursor = &booleanEmptyArrayCursor{}

var FloatEmptyArrayCursor cursors.FloatArrayCursor = &floatEmptyArrayCursor{}

var IntegerEmptyArrayCursor cursors.IntegerArrayCursor = &integerEmptyArrayCursor{}

var StringEmptyArrayCursor cursors.StringArrayCursor = &stringEmptyArrayCursor{}

var UnsignedEmptyArrayCursor cursors.UnsignedArrayCursor = &unsignedEmptyArrayCursor{}

type GroupCursor interface {
	// Next advances to the next cursor. Next will return false when there are no
	// more cursors in the current group.
	Next() bool

	// Cursor returns the most recent cursor after a call to Next.
	Cursor() cursors.Cursor

	// Tags returns the tags for the most recent cursor after a call to Next.
	Tags() models.Tags

	// Keys returns the union of all tag key names for all series produced by
	// this GroupCursor.
	Keys() [][]byte

	// PartitionKeyVals returns the values of all tags identified by the
	// keys specified in ReadRequest#GroupKeys. The tag values values will
	// appear in the same order as the GroupKeys.
	//
	// When the datatypes.GroupNone strategy is specified, PartitionKeyVals will
	// be nil.
	PartitionKeyVals() [][]byte

	// Close releases any resources allocated by the GroupCursor.
	Close()

	// Err returns the first error encountered by the GroupCursor.
	Err() error

	Stats() cursors.CursorStats

	Aggregate() *datatypes.Aggregate
}

type GroupOption func(g *groupResultSet)

type GroupResultSet interface {
	// Next advances the GroupResultSet and returns the next GroupCursor. It
	// returns nil if there are no more groups.
	Next() GroupCursor

	// Close releases any resources allocated by the GroupResultSet.
	Close()

	// Err returns the first error encountered by the GroupResultSet.
	Err() error
}

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

type NodeVisitor interface {
	Visit(*datatypes.Node) NodeVisitor
}

type ResponseStream interface {
	Send(*datatypes.ReadResponse) error
	// SetTrailer sets the trailer metadata which will be sent with the RPC status.
	// When called more than once, all the provided metadata will be merged.
	SetTrailer(metadata.MD)
}

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

type ResultSet interface {
	// Next advances the ResultSet to the next cursor. It returns false
	// when there are no more cursors.
	Next() bool

	// Cursor returns the most recent cursor after a call to Next.
	Cursor() cursors.Cursor

	// Tags returns the tags for the most recent cursor after a call to Next.
	Tags() models.Tags

	// Close releases any resources allocated by the ResultSet.
	Close()

	// Err returns the first error encountered by the ResultSet.
	Err() error

	Stats() cursors.CursorStats
}

type SeriesCursor interface {
	Close()
	Next() *SeriesRow
	Err() error
}

type SeriesRow struct {
	SortKey    []byte
	Name       []byte      // measurement name
	SeriesTags models.Tags // unmodified series tags
	Tags       models.Tags
	Field      string
	Query      cursors.CursorIterators
	ValueCond  influxql.Expr
}

type Store interface {
	ReadFilter(ctx context.Context, req *datatypes.ReadFilterRequest) (ResultSet, error)
	ReadGroup(ctx context.Context, req *datatypes.ReadGroupRequest) (GroupResultSet, error)
	WindowAggregate(ctx context.Context, req *datatypes.ReadWindowAggregateRequest) (ResultSet, error)

	TagKeys(ctx context.Context, req *datatypes.TagKeysRequest) (cursors.StringIterator, error)
	TagValues(ctx context.Context, req *datatypes.TagValuesRequest) (cursors.StringIterator, error)

	GetSource(db, rp string) proto.Message
}

type Valuer interface {
	// Value returns the value and existence flag for a given key.
	Value(key string) (interface{}, bool)
}