var (
	// ErrSessionPoolClosed is returned by a client instance to indicate
	// that client is closed and not able to complete requested operation.
	ErrSessionPoolClosed = errors.New("ydb: table: build client is closed")

	// ErrSessionPoolOverflow is returned by a client instance to indicate
	// that the client is full and requested operation is not able to complete.
	ErrSessionPoolOverflow = errors.New("ydb: table: build client overflow")

	// ErrSessionUnknown is returned by a client instance to indicate that
	// requested build does not exist within the client.
	ErrSessionUnknown = errors.New("ydb: table: unknown build")

	// ErrNoProgress is returned by a client instance to indicate that
	// operation could not be completed.
	ErrNoProgress = errors.New("ydb: table: no progress")
)

var (
	ErrNilConnection = errors.New("build with nil connection")
)

type Client interface {
	table.Client

	Get(ctx context.Context) (s Session, err error)
	Take(ctx context.Context, s Session) (took bool, err error)
	Put(ctx context.Context, s Session) (err error)
	Close(ctx context.Context) error
}

type Session interface {
	table.Session

	Close(ctx context.Context) (err error)
	IsClosed() bool
	Status() string
	OnClose(f func(ctx context.Context))
}

type SessionBuilder func(context.Context) (Session, error)

type SessionProvider interface {
	// Get returns alive idle build or creates new one.
	Get(context.Context) (Session, error)

	// Put takes no longer needed build for reuse or deletion depending
	// on implementation.
	// Put must be fast, if necessary must be async
	Put(context.Context, Session) (err error)

	// CloseSession provides the most effective way of build closing
	// instead of plain build.Close.
	// CloseSession must be fast. If necessary, can be async.
	CloseSession(ctx context.Context, s Session) error

	// Close provide cleanup sessions
	Close(ctx context.Context) error

	// Do provide the best effort for execute operation
	// Do implements internal busy loop until one of the following conditions is met:
	// - deadline was canceled or deadlined
	// - retry operation returned nil as error
	// Warning: if deadline without deadline or cancellation func Retry will be worked infinite
	Do(ctx context.Context, op table.Operation, opts ...table.Option) (err error)
}

type SessionProviderFunc struct {
	OnGet   func(context.Context) (Session, error)
	OnPut   func(context.Context, Session) error
	OnDo    func(context.Context, table.Operation, ...table.Option) error
	OnClose func(context.Context) error
}

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

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