package node

import (
	"fmt"
	"log"
	"sync/atomic"
	"vppn/m"
)

type peerSuper struct {
	// The purpose of this state machine is to manage this published data.
	published *atomic.Pointer[peerRouteInfo]
	staged    peerRouteInfo // Local copy of shared data. See publish().

	// The other remote peers.
	peers *remotePeers

	// Immutable data.
	localIP  byte
	localPub bool
	remoteIP byte
	privKey  []byte
	conn     *connWriter

	// For sending to peer.
	counter *uint64

	// Mutable peer data.
	peer      *m.Peer
	remotePub bool

	// Incoming events.
	peerUpdates    chan *m.Peer
	controlPackets chan controlPacket

	// Buffers
	buf    []byte
	encBuf []byte
}

type stateFunc func() stateFunc

func (s *peerSuper) Run() {
	state := s.noPeer
	for {
		state = state()
	}
}

// ----------------------------------------------------------------------------

func (s *peerSuper) logf(msg string, args ...any) {
	log.Printf(fmt.Sprintf("[%03d] ", s.remoteIP)+msg, args...)
}

// ----------------------------------------------------------------------------

func (s *peerSuper) publish() {
	data := s.staged
	s.published.Store(&data)
}

// ----------------------------------------------------------------------------

func (s *peerSuper) sendControlPacket(pkt interface{ Marshal([]byte) []byte }) {
	buf := pkt.Marshal(s.buf)
	h := header{
		StreamID: controlStreamID,
		Counter:  atomic.AddUint64(s.counter, 1),
		SourceIP: s.localIP,
		DestIP:   s.remoteIP,
	}

	buf = s.staged.controlCipher.Encrypt(h, buf, s.encBuf)
	if s.staged.relayIP != 0 {
		s.peers[s.staged.relayIP].RelayTo(s.remoteIP, buf)
	} else {
		s.conn.WriteTo(buf, s.staged.remoteAddr)
	}
}

// ----------------------------------------------------------------------------

func (s *peerSuper) sendControlPacketDirect(pkt interface{ Marshal([]byte) []byte }) {
	buf := pkt.Marshal(s.buf)
	h := header{
		StreamID: controlStreamID,
		Counter:  atomic.AddUint64(s.counter, 1),
		SourceIP: s.localIP,
		DestIP:   s.remoteIP,
	}

	buf = s.staged.controlCipher.Encrypt(h, buf, s.encBuf)
	s.conn.WriteTo(buf, s.staged.remoteAddr)
}