package node

import (
	"net/netip"
	"sync/atomic"
	"vppn/m"
)

var zeroAddrPort = netip.AddrPort{}

const (
	bufferSize            = 1536
	if_mtu                = 1200
	if_queue_len          = 2048
	controlCipherOverhead = 16
	dataCipherOverhead    = 16
)

type peerRoute struct {
	IP            byte
	Up            bool // True if data can be sent on the route.
	Relay         bool // True if the peer is a relay.
	ControlCipher *controlCipher
	DataCipher    *dataCipher
	RemoteAddr    netip.AddrPort // Remote address if directly connected.
	// TODO: Remove this and use global localAddr and relayIP.
	// Replace w/ a Direct boolean.
	LocalAddr netip.AddrPort // Local address as seen by the remote.
	RelayIP   byte           // Non-zero if we should relay.
}

var (
	// Configuration for this peer.
	netName    string
	localIP    byte
	localPub   bool
	localAddr  netip.AddrPort
	privateKey []byte

	// Shared interface for writing.
	_iface *ifWriter

	// Shared connection for writing.
	_conn *connWriter

	// Counters for sending to each peer.
	sendCounters [256]uint64

	// Duplicate checkers for incoming packets.
	dupChecks [256]*dupCheck

	// Channels for incoming control packets.
	controlPackets [256]chan controlPacket

	// Channels for incoming peer updates from the hub.
	peerUpdates [256]chan *m.Peer

	// Global routing table.
	routingTable [256]*atomic.Pointer[peerRoute]

	// TODO: use relay for local address discovery. This should be new stream ID,
	// managed by a single thread.
	// localAddr *atomic.Pointer[netip.AddrPort]
	// relayIP *atomic.Pointer[byte]
)