config.nim

when (NimMajor, NimMinor) < (1, 4):
  {.push raises: [Defect].}
else:
  {.push raises: [].}

import
  std/[options, sequtils, strutils, net],
  stew/results,
  libp2p/[multiaddress, multicodec]
import ../../waku/waku_core/peers
import ../waku_enr

type NetConfig* = object
  hostAddress*: MultiAddress
  clusterId*: uint16
  wsHostAddress*: Option[MultiAddress]
  hostExtAddress*: Option[MultiAddress]
  wsExtAddress*: Option[MultiAddress]
  wssEnabled*: bool
  extIp*: Option[IpAddress]
  extPort*: Option[Port]
  dns4DomainName*: Option[string]
  announcedAddresses*: seq[MultiAddress]
  extMultiAddrs*: seq[MultiAddress]
  enrMultiAddrs*: seq[MultiAddress]
  enrIp*: Option[IpAddress]
  enrPort*: Option[Port]
  discv5UdpPort*: Option[Port]
  wakuFlags*: Option[CapabilitiesBitfield]
  bindIp*: IpAddress
  bindPort*: Port

type NetConfigResult* = Result[NetConfig, string]

template ip4TcpEndPoint(address, port): MultiAddress =
  MultiAddress.init(address, tcpProtocol, port)

template dns4Ma(dns4DomainName: string): MultiAddress =
  MultiAddress.init("/dns4/" & dns4DomainName).tryGet()

template tcpPortMa(port: Port): MultiAddress =
  MultiAddress.init("/tcp/" & $port).tryGet()

template dns4TcpEndPoint(dns4DomainName: string, port: Port): MultiAddress =
  dns4Ma(dns4DomainName) & tcpPortMa(port)

template wsFlag(wssEnabled: bool): MultiAddress =
  if wssEnabled:
    MultiAddress.init("/wss").tryGet()
  else:
    MultiAddress.init("/ws").tryGet()

proc formatListenAddress(inputMultiAdd: MultiAddress): MultiAddress =
  let inputStr = $inputMultiAdd
  # If MultiAddress contains "0.0.0.0", replace it for "127.0.0.1"
  return MultiAddress.init(inputStr.replace("0.0.0.0", "127.0.0.1")).get()

proc isWsAddress*(ma: MultiAddress): bool =
  let
    isWs = ma.contains(multiCodec("ws")).get()
    isWss = ma.contains(multiCodec("wss")).get()

  return isWs or isWss

proc containsWsAddress(extMultiAddrs: seq[MultiAddress]): bool =
  return extMultiAddrs.filterIt(it.isWsAddress()).len > 0

proc init*(
    T: type NetConfig,
    bindIp: IpAddress,
    bindPort: Port,
    extIp = none(IpAddress),
    extPort = none(Port),
    extMultiAddrs = newSeq[MultiAddress](),
    extMultiAddrsOnly: bool = false,
    wsBindPort: Port = Port(8000),
    wsEnabled: bool = false,
    wssEnabled: bool = false,
    dns4DomainName = none(string),
    discv5UdpPort = none(Port),
    clusterId: uint16 = 0,
    wakuFlags = none(CapabilitiesBitfield),
): NetConfigResult =
  ## Initialize and validate waku node network configuration

  # Bind addresses
  let hostAddress = ip4TcpEndPoint(bindIp, bindPort)

  var wsHostAddress = none(MultiAddress)
  if wsEnabled or wssEnabled:
    try:
      wsHostAddress = some(ip4TcpEndPoint(bindIp, wsbindPort) & wsFlag(wssEnabled))
    except CatchableError:
      return err(getCurrentExceptionMsg())

  let enrIp =
    if extIp.isSome():
      extIp
    else:
      some(bindIp)
  let enrPort =
    if extPort.isSome():
      extPort
    else:
      some(bindPort)

  # Setup external addresses, if available
  var hostExtAddress, wsExtAddress = none(MultiAddress)

  if dns4DomainName.isSome():
    # Use dns4 for externally announced addresses
    try:
      hostExtAddress = some(dns4TcpEndPoint(dns4DomainName.get(), extPort.get()))
    except CatchableError:
      return err(getCurrentExceptionMsg())

    if wsHostAddress.isSome():
      try:
        wsExtAddress =
          some(dns4TcpEndPoint(dns4DomainName.get(), wsBindPort) & wsFlag(wssEnabled))
      except CatchableError:
        return err(getCurrentExceptionMsg())
  else:
    # No public domain name, use ext IP if available
    if extIp.isSome() and extPort.isSome():
      hostExtAddress = some(ip4TcpEndPoint(extIp.get(), extPort.get()))

      if wsHostAddress.isSome():
        try:
          wsExtAddress =
            some(ip4TcpEndPoint(extIp.get(), wsBindPort) & wsFlag(wssEnabled))
        except CatchableError:
          return err(getCurrentExceptionMsg())

  var announcedAddresses = newSeq[MultiAddress]()

  if not extMultiAddrsOnly:
    if hostExtAddress.isSome():
      announcedAddresses.add(hostExtAddress.get())
    else:
      announcedAddresses.add(formatListenAddress(hostAddress))
        # We always have at least a bind address for the host

    if wsExtAddress.isSome():
      announcedAddresses.add(wsExtAddress.get())
    elif wsHostAddress.isSome() and not containsWsAddress(extMultiAddrs):
      # Only publish wsHostAddress if a WS address is not set in extMultiAddrs
      announcedAddresses.add(wsHostAddress.get())

  # External multiaddrs that the operator may have configured
  if extMultiAddrs.len > 0:
    announcedAddresses.add(extMultiAddrs)

  let
    # enrMultiaddrs are just addresses which cannot be represented in ENR, as described in
    # https://rfc.vac.dev/spec/31/#many-connection-types
    enrMultiaddrs = announcedAddresses.filterIt(
      it.hasProtocol("dns4") or it.hasProtocol("dns6") or it.hasProtocol("ws") or
        it.hasProtocol("wss")
    )

  ok(
    NetConfig(
      hostAddress: hostAddress,
      clusterId: clusterId,
      wsHostAddress: wsHostAddress,
      hostExtAddress: hostExtAddress,
      wsExtAddress: wsExtAddress,
      extIp: extIp,
      extPort: extPort,
      wssEnabled: wssEnabled,
      dns4DomainName: dns4DomainName,
      announcedAddresses: announcedAddresses,
      extMultiAddrs: extMultiAddrs,
      enrMultiaddrs: enrMultiaddrs,
      enrIp: enrIp,
      enrPort: enrPort,
      discv5UdpPort: discv5UdpPort,
      bindIp: bindIp,
      bindPort: bindPort,
      wakuFlags: wakuFlags,
    )
  )