client

type Client interface {
	Close() error
	//streamServer
	AddStreamServer(ctx context.Context, StreamServerID int64, addr string) error

	//stream
	GetOrCreateStreamInfoItem(ctx context.Context, name string) (item *store.StreamInfoItem, err error)
	CreateStreamInfoItem(ctx context.Context, name string) (item *store.StreamInfoItem, err error)
	GetStreamInfoItem(ctx context.Context, name string) (item *store.StreamInfoItem, err error)
	GetStreamStat(ctx context.Context, item *store.StreamInfoItem) (begin int64, end int64, err error)
	SetStreamReadOffset(ctx context.Context, sessionID int64, offset int64, item *store.StreamInfoItem) error

	CreateSessionAndReader(ctx context.Context,
		sessionID int64, streamInfo *store.StreamInfoItem) (StreamSession, StreamReader, error)

	//session
	NewStreamSession(ctx context.Context, sessionID int64, streamInfo *store.StreamInfoItem) (StreamSession, error)

	//MQTT
	GetOrCreateMQTTSession(ctx context.Context, clientIdentifier string) (*store.MQTTSessionItem, bool, error)
	UpdateMQTTClientSession(ctx context.Context, clientIdentifier string, Unsubscribe []string, subscribe map[string]int32) error
	DeleteMQTTClientSession(ctx context.Context, clientIdentifier string) (*store.MQTTSessionItem, error)
}

type StreamReader interface {
	io.ReadSeeker
	io.Closer
	Offset() int64
}

type StreamSession interface {
	NewReader() (StreamReader, error)
	NewWriter() (StreamWriter, error)
	SetReadOffset(offset int64) error
	SetReadOffsetWithCb(offset int64, f func(err error))
	GetReadOffset() (offset int64, err error)
}

type StreamWriter interface {
	io.WriteCloser
	Flush() error
	WriteWithCb(data []byte, callback func(err error))
	StreamID() int64
}