# Nimbus - Portal Network
# Copyright (c) 2021 Status Research & Development GmbH
# Licensed and distributed under either of
#   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
#   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
# at your option. This file may not be copied, modified, or distributed except according to those terms.

import
  std/[options, strutils, tables],
  confutils, confutils/std/net, chronicles, chronicles/topics_registry,
  chronos, metrics, metrics/chronos_httpserver, stew/byteutils,
  nimcrypto/[hash, sha2],
  eth/[keys, net/nat],
  eth/p2p/discoveryv5/[enr, node],
  eth/p2p/discoveryv5/protocol as discv5_protocol,
  ../common/common_utils,
  ../content_db,
  ../network/wire/[portal_protocol, portal_stream],
  ../network/history/[history_content, history_network]

const
  defaultListenAddress* = (static ValidIpAddress.init("0.0.0.0"))
  defaultAdminListenAddress* = (static ValidIpAddress.init("127.0.0.1"))

  defaultListenAddressDesc = $defaultListenAddress
  defaultAdminListenAddressDesc = $defaultAdminListenAddress
  # 100mb seems a bit smallish we may consider increasing defaults after some
  # network measurements
  defaultStorageSize* = uint32(1000 * 1000 * 100)

type
  PortalCmd* = enum
    noCommand
    ping
    findNodes
    findContent

  PortalCliConf* = object
    logLevel* {.
      defaultValue: LogLevel.DEBUG
      defaultValueDesc: $LogLevel.DEBUG
      desc: "Sets the log level"
      name: "log-level" .}: LogLevel

    udpPort* {.
      defaultValue: 9009
      desc: "UDP listening port"
      name: "udp-port" .}: uint16

    listenAddress* {.
      defaultValue: defaultListenAddress
      defaultValueDesc: $defaultListenAddressDesc
      desc: "Listening address for the Discovery v5 traffic"
      name: "listen-address" }: ValidIpAddress

    # Note: This will add bootstrap nodes for both Discovery v5 network and each
    # enabled Portal network. No distinction is made on bootstrap nodes per
    # specific network.
    bootstrapNodes* {.
      desc: "ENR URI of node to bootstrap Discovery v5 and the Portal networks from. Argument may be repeated"
      name: "bootstrap-node" .}: seq[Record]

    bootstrapNodesFile* {.
      desc: "Specifies a line-delimited file of ENR URIs to bootstrap Discovery v5 and Portal networks from"
      defaultValue: ""
      name: "bootstrap-file" }: InputFile

    nat* {.
      desc: "Specify method to use for determining public address. " &
            "Must be one of: any, none, upnp, pmp, extip:<IP>"
      defaultValue: NatConfig(hasExtIp: false, nat: NatAny)
      defaultValueDesc: "any"
      name: "nat" .}: NatConfig

    enrAutoUpdate* {.
      defaultValue: false
      desc: "Discovery can automatically update its ENR with the IP address " &
            "and UDP port as seen by other nodes it communicates with. " &
            "This option allows to enable/disable this functionality"
      name: "enr-auto-update" .}: bool

    networkKey* {.
      desc: "Private key (secp256k1) for the p2p network, hex encoded.",
      defaultValue: PrivateKey.random(keys.newRng()[])
      defaultValueDesc: "random"
      name: "network-key" .}: PrivateKey

    metricsEnabled* {.
      defaultValue: false
      desc: "Enable the metrics server"
      name: "metrics" .}: bool

    metricsAddress* {.
      defaultValue: defaultAdminListenAddress
      defaultValueDesc: $defaultAdminListenAddressDesc
      desc: "Listening address of the metrics server"
      name: "metrics-address" .}: ValidIpAddress

    metricsPort* {.
      defaultValue: 8008
      desc: "Listening HTTP port of the metrics server"
      name: "metrics-port" .}: Port

    protocolId* {.
      defaultValue: historyProtocolId
      desc: "Portal wire protocol id for the network to connect to"
      name: "protocol-id" .}: PortalProtocolId

    # TODO maybe it is worth defining minimal storage size and throw error if
    # value provided is smaller than minimum
    storageSize* {.
      desc: "Maximum amount (in bytes) of content which will be stored " &
            "in local database."
      defaultValue: defaultStorageSize
      name: "storage-size" .}: uint32

    case cmd* {.
      command
      defaultValue: noCommand }: PortalCmd
    of noCommand:
      discard
    of ping:
      pingTarget* {.
        argument
        desc: "ENR URI of the node to a send ping message"
        name: "node" .}: Node
    of findNodes:
      distance* {.
        defaultValue: 255
        desc: "Distance parameter for the findNodes message"
        name: "distance" .}: uint16
      # TODO: Order here matters as else the help message does not show all the
      # information, see: https://github.com/status-im/nim-confutils/issues/15
      findNodesTarget* {.
        argument
        desc: "ENR URI of the node to send a findNodes message"
        name: "node" .}: Node
    of findContent:
      findContentTarget* {.
        argument
        desc: "ENR URI of the node to send a findContent message"
        name: "node" .}: Node

proc parseCmdArg*(T: type enr.Record, p: TaintedString): T =
  if not fromURI(result, p):
    raise newException(ConfigurationError, "Invalid ENR")

proc completeCmdArg*(T: type enr.Record, val: TaintedString): seq[string] =
  return @[]

proc parseCmdArg*(T: type Node, p: TaintedString): T =
  var record: enr.Record
  if not fromURI(record, p):
    raise newException(ConfigurationError, "Invalid ENR")

  let n = newNode(record)
  if n.isErr:
    raise newException(ConfigurationError, $n.error)

  if n[].address.isNone():
    raise newException(ConfigurationError, "ENR without address")

  n[]

proc completeCmdArg*(T: type Node, val: TaintedString): seq[string] =
  return @[]

proc parseCmdArg*(T: type PrivateKey, p: TaintedString): T =
  try:
    result = PrivateKey.fromHex(string(p)).tryGet()
  except CatchableError:
    raise newException(ConfigurationError, "Invalid private key")

proc completeCmdArg*(T: type PrivateKey, val: TaintedString): seq[string] =
  return @[]

proc parseCmdArg*(T: type PortalProtocolId, p: TaintedString): T =
  try:
    result = byteutils.hexToByteArray(string(p), 2)
  except ValueError:
    raise newException(ConfigurationError,
      "Invalid protocol id, not a valid hex value")

proc completeCmdArg*(T: type PortalProtocolId, val: TaintedString): seq[string] =
  return @[]

proc discover(d: discv5_protocol.Protocol) {.async.} =
  while true:
    let discovered = await d.queryRandom()
    info "Lookup finished", nodes = discovered.len
    await sleepAsync(30.seconds)

proc testContentIdHandler(contentKey: ByteList): Option[ContentId] =
  # Note: Returning a static content id here, as in practice this depends
  # on the content key to content id derivation, which is different for the
  # different content networks. And we want these tests to be independent from
  # that.
  let idHash = sha256.digest("test")
  some(readUintBE[256](idHash.data))

proc dbGetHandler(db: ContentDB, contentId: ContentId):
    Option[seq[byte]] =
  db.get(contentId)

proc run(config: PortalCliConf) =
  let
    rng = newRng()
    bindIp = config.listenAddress
    udpPort = Port(config.udpPort)
    # TODO: allow for no TCP port mapping!
    (extIp, _, extUdpPort) = setupAddress(config.nat,
      config.listenAddress, udpPort, udpPort, "portalcli")

  var bootstrapRecords: seq[Record]
  loadBootstrapFile(string config.bootstrapNodesFile, bootstrapRecords)
  bootstrapRecords.add(config.bootstrapNodes)

  let d = newProtocol(
    config.networkKey,
    extIp, none(Port), extUdpPort,
    bootstrapRecords = bootstrapRecords,
    bindIp = bindIp, bindPort = udpPort,
    enrAutoUpdate = config.enrAutoUpdate,
    rng = rng)

  d.open()

  let
    db = ContentDB.new("", config.storageSize, inMemory = true)
    sm = StreamManager.new(d)
    cq = newAsyncQueue[(ContentKeysList, seq[seq[byte]])](50)
    stream = sm.registerNewStream(cq)
    portal = PortalProtocol.new(d, config.protocolId, db,
      testContentIdHandler, dbGetHandler, stream,
      bootstrapRecords = bootstrapRecords)

  if config.metricsEnabled:
    let
      address = config.metricsAddress
      port = config.metricsPort
    notice "Starting metrics HTTP server",
      url = "http://" & $address & ":" & $port & "/metrics"
    try:
      chronos_httpserver.startMetricsHttpServer($address, port)
    except CatchableError as exc: raise exc
    except Exception as exc: raiseAssert exc.msg # TODO fix metrics

  case config.cmd
  of ping:
    let pong = waitFor portal.ping(config.pingTarget)

    if pong.isOk():
      echo pong.get()
    else:
      echo pong.error
  of findNodes:
    let distances = @[config.distance]
    let nodes = waitFor portal.findNodes(config.findNodesTarget, distances)

    if nodes.isOk():
      for node in nodes.get():
        echo $node.record & " - " & shortLog(node)
    else:
      echo nodes.error
  of findContent:
    proc random(T: type UInt256, rng: var HmacDrbgContext): T =
      rng.generate(T)

    # For now just some random bytes
    let contentKey = ByteList.init(@[1'u8])

    let foundContent = waitFor portal.findContent(config.findContentTarget,
      contentKey)

    if foundContent.isOk():
      echo foundContent.get()
    else:
      echo foundContent.error

  of noCommand:
    d.start()
    portal.start()
    waitFor(discover(d))

when isMainModule:
  let config = PortalCliConf.load()

  setLogLevel(config.logLevel)

  run(config)