srt

type AcceptFunc func(req ConnRequest) ConnType

type Config struct {
	// Type of congestion control. 'live' or 'file'
	// SRTO_CONGESTION
	Congestion string

	// Connection timeout.
	// SRTO_CONNTIMEO
	ConnectionTimeout time.Duration

	// Enable drift tracer.
	// SRTO_DRIFTTRACER
	DriftTracer bool

	// Reject connection if parties set different passphrase.
	// SRTO_ENFORCEDENCRYPTION
	EnforcedEncryption bool

	// Flow control window size. Packets.
	// SRTO_FC
	FC uint32

	// Accept group connections.
	// SRTO_GROUPCONNECT
	GroupConnect bool

	// Group stability timeout.
	// SRTO_GROUPSTABTIMEO
	GroupStabilityTimeout time.Duration

	// Input bandwidth. Bytes.
	// SRTO_INPUTBW
	InputBW int64

	// IP socket type of service
	// SRTO_IPTOS
	IPTOS int

	// Defines IP socket "time to live" option.
	// SRTO_IPTTL
	IPTTL int

	// Allow only IPv6.
	// SRTO_IPV6ONLY
	IPv6Only int

	// Duration of Stream Encryption key switchover. Packets.
	// SRTO_KMPREANNOUNCE
	KMPreAnnounce uint64

	// Stream encryption key refresh rate. Packets.
	// SRTO_KMREFRESHRATE
	KMRefreshRate uint64

	// Defines the maximum accepted transmission latency.
	// SRTO_LATENCY
	Latency time.Duration

	// Packet reorder tolerance.
	// SRTO_LOSSMAXTTL
	LossMaxTTL uint32

	// Bandwidth limit in bytes/s.
	// SRTO_MAXBW
	MaxBW int64

	// Enable SRT message mode.
	// SRTO_MESSAGEAPI
	MessageAPI bool

	// Minimum input bandwidth
	// This option is effective only if both SRTO_MAXBW and SRTO_INPUTBW are set to 0. It controls the minimum allowed value of the input bitrate estimate.
	// SRTO_MININPUTBW
	MinInputBW int64

	// Minimum SRT library version of a peer.
	// SRTO_MINVERSION
	MinVersion uint32

	// MTU size
	// SRTO_MSS
	MSS uint32

	// Enable periodic NAK reports
	// SRTO_NAKREPORT
	NAKReport bool

	// Limit bandwidth overhead, percents
	// SRTO_OHEADBW
	OverheadBW int64

	// Set up the packet filter.
	// SRTO_PACKETFILTER
	PacketFilter string

	// Password for the encrypted transmission.
	// SRTO_PASSPHRASE
	Passphrase string

	// Maximum payload size. Bytes.
	// SRTO_PAYLOADSIZE
	PayloadSize uint32

	// Crypto key length in bytes.
	// SRTO_PBKEYLEN
	PBKeylen int

	// Peer idle timeout.
	// SRTO_PEERIDLETIMEO
	PeerIdleTimeout time.Duration

	// Minimum receiver latency to be requested by sender.
	// SRTO_PEERLATENCY
	PeerLatency time.Duration

	// Receiver buffer size. Bytes.
	// SRTO_RCVBUF
	ReceiverBufferSize uint32

	// Receiver-side latency.
	// SRTO_RCVLATENCY
	ReceiverLatency time.Duration

	// Sender buffer size. Bytes.
	// SRTO_SNDBUF
	SendBufferSize uint32

	// Sender's delay before dropping packets.
	// SRTO_SNDDROPDELAY
	SendDropDelay time.Duration

	// Stream ID (settable in caller mode only, visible on the listener peer)
	// SRTO_STREAMID
	StreamId string

	// Drop too late packets.
	// SRTO_TLPKTDROP
	TooLatePacketDrop bool

	// Transmission type. 'live' or 'file'.
	// SRTO_TRANSTYPE
	TransmissionType string

	// Timestamp-based packet delivery mode.
	// SRTO_TSBPDMODE
	TSBPDMode bool

	// An implementation of the Logger interface
	Logger Logger
}

type Conn interface {
	// Read reads data from the connection.
	// Read can be made to time out and return an error after a fixed
	// time limit; see SetDeadline and SetReadDeadline.
	Read(p []byte) (int, error)

	// ReadPacket reads a packet from the queue of received packets. It blocks
	// if the queue is empty. Only data packets are returned. Using ReadPacket
	// and Read at the same time may lead to data loss.
	ReadPacket() (packet.Packet, error)

	// Write writes data to the connection.
	// Write can be made to time out and return an error after a fixed
	// time limit; see SetDeadline and SetWriteDeadline.
	Write(p []byte) (int, error)

	// WritePacket writes a packet to the write queue. Packets on the write queue
	// will be sent to the peer of the connection. Only data packets will be sent.
	WritePacket(p packet.Packet) error

	// Close closes the connection.
	// Any blocked Read or Write operations will be unblocked and return errors.
	Close() error

	// LocalAddr returns the local network address. The returned net.Addr is not shared by other invocations of LocalAddr.
	LocalAddr() net.Addr

	// RemoteAddr returns the remote network address. The returned net.Addr is not shared by other invocations of RemoteAddr.
	RemoteAddr() net.Addr

	SetDeadline(t time.Time) error
	SetReadDeadline(t time.Time) error
	SetWriteDeadline(t time.Time) error

	// SocketId return the socketid of the connection.
	SocketId() uint32

	// PeerSocketId returns the socketid of the peer of the connection.
	PeerSocketId() uint32

	// StreamId returns the streamid use for the connection.
	StreamId() string

	// Stats returns accumulated and instantaneous statistics of the connection.
	Stats(s *Statistics)

	// Version returns the connection version, either 4 or 5. With version 4, the streamid is not available
	Version() uint32
}

type ConnRequest interface {
	// RemoteAddr returns the address of the peer. The returned net.Addr
	// is a copy and can be used at will.
	RemoteAddr() net.Addr

	// Version returns the handshake version of the incoming request. Currently
	// known versions are 4 and 5. With version 4 the StreamId will always be
	// empty and IsEncrypted will always return false. An incoming version 4
	// connection will always be publishing.
	Version() uint32

	// StreamId returns the streamid of the requesting connection. Use this
	// to decide what to do with the connection.
	StreamId() string

	// IsEncrypted returns whether the connection is encrypted. If it is
	// encrypted, use SetPassphrase to set the passphrase for decrypting.
	IsEncrypted() bool

	// SetPassphrase sets the passphrase in order to decrypt the incoming
	// data. Returns an error if the passphrase did not work or the connection
	// is not encrypted.
	SetPassphrase(p string) error

	// SetRejectionReason sets the rejection reason for the connection. If
	// no set, REJ_PEER will be used.
	SetRejectionReason(r RejectionReason)
}

type ConnType int

type Listener interface {
	// Accept waits for new connections. For each new connection the AcceptFunc
	// gets called. Conn is a new connection if AcceptFunc is PUBLISH or SUBSCRIBE.
	// If AcceptFunc returns REJECT, Conn is nil. In case of failure error is not
	// nil, Conn is nil and ConnType is REJECT. On closing the listener err will
	// be ErrListenerClosed and ConnType is REJECT.
	Accept(AcceptFunc) (Conn, ConnType, error)

	// Close closes the listener. It will stop accepting new connections and
	// close all currently established connections.
	Close()

	// Addr returns the address of the listener.
	Addr() net.Addr
}

type Log struct {
	Time     time.Time // Time of when this message has been logged
	SocketId uint32    // The socketid if connection related, 0 otherwise
	Topic    string    // The topic of this message
	Message  string    // The message itself
	File     string    // The file in which this message has been dispatched
	Line     int       // The line number in the file in which this message has been dispatched
}

type Logger interface {
	// HasTopic returns whether this Logger is logging messages of that topic.
	HasTopic(topic string) bool

	// Print adds a new message to the message queue. The message itself is
	// a function that returns the string to be logges. It will only be
	// executed if HasTopic returns true on the given topic.
	Print(topic string, socketId uint32, skip int, message func() string)

	// Listen returns a read channel for Log messages.
	Listen() <-chan Log

	// Close closes the logger. No more messages will be logged.
	Close()
}

type PubSub interface {
	// Publish accepts a SRT connection where it reads from. It blocks
	// until the connection closes. The returned error indicates why it
	// stopped. There can be only one publisher.
	Publish(c Conn) error

	// Subscribe accepts a SRT connection where it writes the data from
	// the publisher to. It blocks until an error happens. If the publisher
	// disconnects, io.EOF is returned. There can be an arbitrary number
	// of subscribers.
	Subscribe(c Conn) error
}

type PubSubConfig struct {
	Logger Logger // Optional logger
}

type RejectionReason uint32

type Server struct {
	// The address the SRT server should listen on, e.g. ":6001".
	Addr string

	// Config is the configuration for a SRT listener.
	Config *Config

	// HandleConnect will be called for each incoming connection. This
	// allows you to implement your own interpretation of the streamid
	// and authorization. If this is nil, all connections will be
	// rejected.
	HandleConnect AcceptFunc

	// HandlePublish will be called for a publishing connection.
	HandlePublish func(conn Conn)

	// HandlePublish will be called for a subscribing connection.
	HandleSubscribe func(conn Conn)
	// contains filtered or unexported fields
}

type Statistics struct {
	MsTimeStamp uint64 // The time elapsed, in milliseconds, since the SRT socket has been created

	// Accumulated
	Accumulated StatisticsAccumulated

	// Interval
	Interval StatisticsInterval

	// Instantaneous
	Instantaneous StatisticsInstantaneous
}

type StatisticsAccumulated struct {
	PktSent          uint64 // The total number of sent DATA packets, including retransmitted packets
	PktRecv          uint64 // The total number of received DATA packets, including retransmitted packets
	PktSentUnique    uint64 // The total number of unique DATA packets sent by the SRT sender
	PktRecvUnique    uint64 // The total number of unique original, retransmitted or recovered by the packet filter DATA packets received in time, decrypted without errors and, as a result, scheduled for delivery to the upstream application by the SRT receiver.
	PktSendLoss      uint64 // The total number of data packets considered or reported as lost at the sender side. Does not correspond to the packets detected as lost at the receiver side.
	PktRecvLoss      uint64 // The total number of SRT DATA packets detected as presently missing (either reordered or lost) at the receiver side
	PktRetrans       uint64 // The total number of retransmitted packets sent by the SRT sender
	PktRecvRetrans   uint64 // The total number of retransmitted packets registered at the receiver side
	PktSentACK       uint64 // The total number of sent ACK (Acknowledgement) control packets
	PktRecvACK       uint64 // The total number of received ACK (Acknowledgement) control packets
	PktSentNAK       uint64 // The total number of sent NAK (Negative Acknowledgement) control packets
	PktRecvNAK       uint64 // The total number of received NAK (Negative Acknowledgement) control packets
	PktSentKM        uint64 // The total number of sent KM (Key Material) control packets
	PktRecvKM        uint64 // The total number of received KM (Key Material) control packets
	UsSndDuration    uint64 // The total accumulated time in microseconds, during which the SRT sender has some data to transmit, including packets that have been sent, but not yet acknowledged
	PktRecvBelated   uint64
	PktSendDrop      uint64 // The total number of dropped by the SRT sender DATA packets that have no chance to be delivered in time
	PktRecvDrop      uint64 // The total number of dropped by the SRT receiver and, as a result, not delivered to the upstream application DATA packets
	PktRecvUndecrypt uint64 // The total number of packets that failed to be decrypted at the receiver side

	ByteSent          uint64 // Same as pktSent, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecv          uint64 // Same as pktRecv, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteSentUnique    uint64 // Same as pktSentUnique, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvUnique    uint64 // Same as pktRecvUnique, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvLoss      uint64 // Same as pktRecvLoss, but expressed in bytes, including payload and all the headers (IP, TCP, SRT), bytes for the presently missing (either reordered or lost) packets' payloads are estimated based on the average packet size
	ByteRetrans       uint64 // Same as pktRetrans, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvRetrans   uint64 // Same as pktRecvRetrans, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvBelated   uint64
	ByteSendDrop      uint64 // Same as pktSendDrop, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvDrop      uint64 // Same as pktRecvDrop, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvUndecrypt uint64 // Same as pktRecvUndecrypt, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
}

type StatisticsInstantaneous struct {
	UsPktSendPeriod       float64 // Current minimum time interval between which consecutive packets are sent, in microseconds
	PktFlowWindow         uint64  // The maximum number of packets that can be "in flight"
	PktFlightSize         uint64  // The number of packets in flight
	MsRTT                 float64 // Smoothed round-trip time (SRTT), an exponentially-weighted moving average (EWMA) of an endpoint's RTT samples, in milliseconds
	MbpsSentRate          float64 // Current transmission bandwidth, in Mbps
	MbpsRecvRate          float64 // Current receiving bandwidth, in Mbps
	MbpsLinkCapacity      float64 // Estimated capacity of the network link, in Mbps
	ByteAvailSendBuf      uint64  // The available space in the sender's buffer, in bytes
	ByteAvailRecvBuf      uint64  // The available space in the receiver's buffer, in bytes
	MbpsMaxBW             float64 // Transmission bandwidth limit, in Mbps
	ByteMSS               uint64  // Maximum Segment Size (MSS), in bytes
	PktSendBuf            uint64  // The number of packets in the sender's buffer that are already scheduled for sending or even possibly sent, but not yet acknowledged
	ByteSendBuf           uint64  // Instantaneous (current) value of pktSndBuf, but expressed in bytes, including payload and all headers (IP, TCP, SRT)
	MsSendBuf             uint64  // The timespan (msec) of packets in the sender's buffer (unacknowledged packets)
	MsSendTsbPdDelay      uint64  // Timestamp-based Packet Delivery Delay value of the peer
	PktRecvBuf            uint64  // The number of acknowledged packets in receiver's buffer
	ByteRecvBuf           uint64  // Instantaneous (current) value of pktRcvBuf, expressed in bytes, including payload and all headers (IP, TCP, SRT)
	MsRecvBuf             uint64  // The timespan (msec) of acknowledged packets in the receiver's buffer
	MsRecvTsbPdDelay      uint64  // Timestamp-based Packet Delivery Delay value set on the socket via SRTO_RCVLATENCY or SRTO_LATENCY
	PktReorderTolerance   uint64  // Instant value of the packet reorder tolerance
	PktRecvAvgBelatedTime uint64  // Accumulated difference between the current time and the time-to-play of a packet that is received late
	PktSendLossRate       float64 // Percentage of resent data vs. sent data
	PktRecvLossRate       float64 // Percentage of retransmitted data vs. received data
}

type StatisticsInterval struct {
	MsInterval uint64 // Length of the interval, in milliseconds

	PktSent        uint64 // Number of sent DATA packets, including retransmitted packets
	PktRecv        uint64 // Number of received DATA packets, including retransmitted packets
	PktSentUnique  uint64 // Number of unique DATA packets sent by the SRT sender
	PktRecvUnique  uint64 // Number of unique original, retransmitted or recovered by the packet filter DATA packets received in time, decrypted without errors and, as a result, scheduled for delivery to the upstream application by the SRT receiver.
	PktSendLoss    uint64 // Number of data packets considered or reported as lost at the sender side. Does not correspond to the packets detected as lost at the receiver side.
	PktRecvLoss    uint64 // Number of SRT DATA packets detected as presently missing (either reordered or lost) at the receiver side
	PktRetrans     uint64 // Number of retransmitted packets sent by the SRT sender
	PktRecvRetrans uint64 // Number of retransmitted packets registered at the receiver side
	PktSentACK     uint64 // Number of sent ACK (Acknowledgement) control packets
	PktRecvACK     uint64 // Number of received ACK (Acknowledgement) control packets
	PktSentNAK     uint64 // Number of sent NAK (Negative Acknowledgement) control packets
	PktRecvNAK     uint64 // Number of received NAK (Negative Acknowledgement) control packets

	MbpsSendRate float64 // Sending rate, in Mbps
	MbpsRecvRate float64 // Receiving rate, in Mbps

	UsSndDuration uint64 // Accumulated time in microseconds, during which the SRT sender has some data to transmit, including packets that have been sent, but not yet acknowledged

	PktReorderDistance uint64
	PktRecvBelated     uint64 // Number of packets that arrive too late
	PktSndDrop         uint64 // Number of dropped by the SRT sender DATA packets that have no chance to be delivered in time
	PktRecvDrop        uint64 // Number of dropped by the SRT receiver and, as a result, not delivered to the upstream application DATA packets
	PktRecvUndecrypt   uint64 // Number of packets that failed to be decrypted at the receiver side

	ByteSent          uint64 // Same as pktSent, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecv          uint64 // Same as pktRecv, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteSentUnique    uint64 // Same as pktSentUnique, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvUnique    uint64 // Same as pktRecvUnique, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvLoss      uint64 // Same as pktRecvLoss, but expressed in bytes, including payload and all the headers (IP, TCP, SRT), bytes for the presently missing (either reordered or lost) packets' payloads are estimated based on the average packet size
	ByteRetrans       uint64 // Same as pktRetrans, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvRetrans   uint64 // Same as pktRecvRetrans, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvBelated   uint64 // Same as pktRecvBelated, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteSendDrop      uint64 // Same as pktSendDrop, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvDrop      uint64 // Same as pktRecvDrop, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
	ByteRecvUndecrypt uint64 // Same as pktRecvUndecrypt, but expressed in bytes, including payload and all the headers (IP, TCP, SRT)
}