## Logos Storage
## Copyright (c) 2021 Status Research & Development GmbH
## Licensed under either of
##  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
##  * MIT license ([LICENSE-MIT](LICENSE-MIT))
## at your option.
## This file may not be copied, modified, or distributed except according to
## those terms.

{.push raises: [].}

import std/os

{.push warning[UnusedImport]: on.}
import std/terminal # Is not used in tests
{.pop.}

import std/options
import std/parseutils
import std/strutils
import std/typetraits
import std/net

import pkg/chronos
import pkg/chronicles/helpers
import pkg/chronicles/topics_registry
import pkg/confutils/defs
import pkg/confutils/std/net
import pkg/toml_serialization
import pkg/metrics
import pkg/metrics/chronos_httpserver
import pkg/stew/byteutils
import pkg/libp2p
import pkg/questionable
import pkg/questionable/results
import pkg/stew/base64

import ./codextypes
import ./discovery
import ./logutils
import ./stores
import ./units
import ./utils
import ./nat
import ./utils/natutils

from ./blockexchange/engine/pendingblocks import DefaultBlockRetries

export units, net, codextypes, logutils, completeCmdArg, parseCmdArg, NatConfig

export
  DefaultQuotaBytes, DefaultBlockTtl, DefaultBlockInterval, DefaultNumBlocksPerInterval,
  DefaultBlockRetries

type ThreadCount* = distinct Natural

proc `==`*(a, b: ThreadCount): bool {.borrow.}

proc defaultDataDir*(): string =
  let dataDir =
    when defined(windows):
      "AppData" / "Roaming" / "Storage"
    elif defined(macosx):
      "Library" / "Application Support" / "Storage"
    else:
      ".cache" / "storage"

  getHomeDir() / dataDir

const
  storage_enable_api_debug_peers* {.booldefine.} = false
  storage_enable_log_counter* {.booldefine.} = false

  DefaultThreadCount* = ThreadCount(0)

type
  StartUpCmd* {.pure.} = enum
    noCmd
    persistence

  LogKind* {.pure.} = enum
    Auto = "auto"
    Colors = "colors"
    NoColors = "nocolors"
    Json = "json"
    None = "none"

  RepoKind* = enum
    repoFS = "fs"
    repoSQLite = "sqlite"
    repoLevelDb = "leveldb"

  CodexConf* = object
    configFile* {.
      desc: "Loads the configuration from a TOML file",
      defaultValueDesc: "none",
      defaultValue: InputFile.none,
      name: "config-file"
    .}: Option[InputFile]

    logLevel* {.defaultValue: "info", desc: "Sets the log level", name: "log-level".}:
      string

    logFormat* {.
      desc:
        "Specifies what kind of logs should be written to stdout (auto, " &
        "colors, nocolors, json)",
      defaultValueDesc: "auto",
      defaultValue: LogKind.Auto,
      name: "log-format"
    .}: LogKind

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

    metricsAddress* {.
      desc: "Listening address of the metrics server",
      defaultValue: defaultAddress(config),
      defaultValueDesc: "127.0.0.1",
      name: "metrics-address"
    .}: IpAddress

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

    dataDir* {.
      desc: "The directory where Storage will store configuration and data",
      defaultValue: defaultDataDir(),
      defaultValueDesc: "",
      abbr: "d",
      name: "data-dir"
    .}: OutDir

    listenAddrs* {.
      desc: "Multi Addresses to listen on",
      defaultValue:
        @[MultiAddress.init("/ip4/0.0.0.0/tcp/0").expect("Should init multiaddress")],
      defaultValueDesc: "/ip4/0.0.0.0/tcp/0",
      abbr: "i",
      name: "listen-addrs"
    .}: seq[MultiAddress]

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

    discoveryPort* {.
      desc: "Discovery (UDP) port",
      defaultValue: 8090.Port,
      defaultValueDesc: "8090",
      abbr: "u",
      name: "disc-port"
    .}: Port

    netPrivKeyFile* {.
      desc: "Source of network (secp256k1) private key file path or name",
      defaultValue: "key",
      name: "net-privkey"
    .}: string

    bootstrapNodes* {.
      desc:
        "Specifies one or more bootstrap nodes to use when " &
        "connecting to the network",
      abbr: "b",
      name: "bootstrap-node"
    .}: seq[SignedPeerRecord]

    maxPeers* {.
      desc: "The maximum number of peers to connect to",
      defaultValue: 160,
      name: "max-peers"
    .}: int

    numThreads* {.
      desc:
        "Number of worker threads (\"0\" = use as many threads as there are CPU cores available)",
      defaultValue: DefaultThreadCount,
      name: "num-threads"
    .}: ThreadCount

    agentString* {.
      defaultValue: "Logos Storage",
      desc: "Node agent string which is used as identifier in network",
      name: "agent-string"
    .}: string

    apiBindAddress* {.
      desc: "The REST API bind address",
      defaultValue: "127.0.0.1".some,
      name: "api-bindaddr"
    .}: Option[string]

    apiPort* {.
      desc: "The REST Api port",
      defaultValue: 8080.Port,
      defaultValueDesc: "8080",
      name: "api-port",
      abbr: "p"
    .}: Port

    apiCorsAllowedOrigin* {.
      desc:
        "The REST Api CORS allowed origin for downloading data. " &
        "'*' will allow all origins, '' will allow none.",
      defaultValue: string.none,
      defaultValueDesc: "Disallow all cross origin requests to download data",
      name: "api-cors-origin"
    .}: Option[string]

    repoKind* {.
      desc: "Backend for main repo store (fs, sqlite, leveldb)",
      defaultValueDesc: "fs",
      defaultValue: repoFS,
      name: "repo-kind"
    .}: RepoKind

    storageQuota* {.
      desc: "The size of the total storage quota dedicated to the node",
      defaultValue: DefaultQuotaBytes,
      defaultValueDesc: $DefaultQuotaBytes,
      name: "storage-quota",
      abbr: "q"
    .}: NBytes

    blockTtl* {.
      desc: "Default block timeout in seconds - 0 disables the ttl",
      defaultValue: DefaultBlockTtl,
      defaultValueDesc: $DefaultBlockTtl,
      name: "block-ttl",
      abbr: "t"
    .}: Duration

    blockMaintenanceInterval* {.
      desc:
        "Time interval in seconds - determines frequency of block " &
        "maintenance cycle: how often blocks are checked " & "for expiration and cleanup",
      defaultValue: DefaultBlockInterval,
      defaultValueDesc: $DefaultBlockInterval,
      name: "block-mi"
    .}: Duration

    blockMaintenanceNumberOfBlocks* {.
      desc: "Number of blocks to check every maintenance cycle",
      defaultValue: DefaultNumBlocksPerInterval,
      defaultValueDesc: $DefaultNumBlocksPerInterval,
      name: "block-mn"
    .}: int

    blockRetries* {.
      desc: "Number of times to retry fetching a block before giving up",
      defaultValue: DefaultBlockRetries,
      defaultValueDesc: $DefaultBlockRetries,
      name: "block-retries"
    .}: int

    cacheSize* {.
      desc:
        "The size of the block cache, 0 disables the cache - " &
        "might help on slow hardrives",
      defaultValue: 0,
      defaultValueDesc: "0",
      name: "cache-size",
      abbr: "c"
    .}: NBytes

    logFile* {.
      desc: "Logs to file", defaultValue: string.none, name: "log-file", hidden
    .}: Option[string]

func defaultAddress*(conf: CodexConf): IpAddress =
  result = static parseIpAddress("127.0.0.1")

func defaultNatConfig*(): NatConfig =
  result = NatConfig(hasExtIp: false, nat: NatStrategy.NatAny)

proc getCodexVersion(): string =
  let tag = strip(staticExec("git describe --tags --abbrev=0"))
  if tag.isEmptyOrWhitespace:
    return "untagged build"
  return tag

proc getCodexRevision(): string =
  # using a slice in a static context breaks nimsuggest for some reason
  var res = strip(staticExec("git rev-parse --short HEAD"))
  return res

proc getNimBanner(): string =
  staticExec("nim --version | grep Version")

const
  codexVersion* = getCodexVersion()
  codexRevision* = getCodexRevision()
  nimBanner* = getNimBanner()

  codexFullVersion* =
    "Storage version:  " & codexVersion & "\p" & "Storage revision: " & codexRevision &
    "\p"

proc parseCmdArg*(
    T: typedesc[MultiAddress], input: string
): MultiAddress {.raises: [ValueError].} =
  var ma: MultiAddress
  try:
    let res = MultiAddress.init(input)
    if res.isOk:
      ma = res.get()
    else:
      fatal "Invalid MultiAddress", input = input, error = res.error()
      quit QuitFailure
  except LPError as exc:
    fatal "Invalid MultiAddress uri", uri = input, error = exc.msg
    quit QuitFailure
  ma

proc parse*(T: type ThreadCount, p: string): Result[ThreadCount, string] =
  try:
    let count = parseInt(p)
    if count != 0 and count < 2:
      return err("Invalid number of threads: " & p)
    return ok(ThreadCount(count))
  except ValueError as e:
    return err("Invalid number of threads: " & p & ", error=" & e.msg)

proc parseCmdArg*(T: type ThreadCount, input: string): T =
  let val = ThreadCount.parse(input)
  if val.isErr:
    fatal "Cannot parse the thread count.", input = input, error = val.error()
    quit QuitFailure
  return val.get()

proc parse*(T: type SignedPeerRecord, p: string): Result[SignedPeerRecord, string] =
  var res: SignedPeerRecord
  try:
    if not res.fromURI(p):
      return err("The uri is not a valid SignedPeerRecord: " & p)
    return ok(res)
  except LPError, Base64Error:
    let e = getCurrentException()
    return err(e.msg)

proc parseCmdArg*(T: type SignedPeerRecord, uri: string): T =
  let res = SignedPeerRecord.parse(uri)
  if res.isErr:
    fatal "Cannot parse the signed peer.", error = res.error(), input = uri
    quit QuitFailure
  return res.get()

func parse*(T: type NatConfig, p: string): Result[NatConfig, string] =
  case p.toLowerAscii
  of "any":
    return ok(NatConfig(hasExtIp: false, nat: NatStrategy.NatAny))
  of "none":
    return ok(NatConfig(hasExtIp: false, nat: NatStrategy.NatNone))
  of "upnp":
    return ok(NatConfig(hasExtIp: false, nat: NatStrategy.NatUpnp))
  of "pmp":
    return ok(NatConfig(hasExtIp: false, nat: NatStrategy.NatPmp))
  else:
    if p.startsWith("extip:"):
      try:
        let ip = parseIpAddress(p[6 ..^ 1])
        return ok(NatConfig(hasExtIp: true, extIp: ip))
      except ValueError:
        let error = "Not a valid IP address: " & p[6 ..^ 1]
        return err(error)
    else:
      return err("Not a valid NAT option: " & p)

proc parseCmdArg*(T: type NatConfig, p: string): T =
  let res = NatConfig.parse(p)
  if res.isErr:
    fatal "Cannot parse the NAT config.", error = res.error(), input = p
    quit QuitFailure
  return res.get()

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

func parse*(T: type NBytes, p: string): Result[NBytes, string] =
  var num = 0'i64
  let count = parseSize(p, num, alwaysBin = true)
  if count == 0:
    return err("Invalid number of bytes: " & p)
  return ok(NBytes(num))

proc parseCmdArg*(T: type NBytes, val: string): T =
  let res = NBytes.parse(val)
  if res.isErr:
    fatal "Cannot parse NBytes.", error = res.error(), input = val
    quit QuitFailure
  return res.get()

proc parseCmdArg*(T: type Duration, val: string): T =
  var dur: Duration
  let count = parseDuration(val, dur)
  if count == 0:
    fatal "Cannot parse duration", dur = dur
    quit QuitFailure
  dur

proc readValue*(r: var TomlReader, val: var SignedPeerRecord) =
  without uri =? r.readValue(string).catch, err:
    error "invalid SignedPeerRecord configuration value", error = err.msg
    quit QuitFailure

  try:
    val = SignedPeerRecord.parseCmdArg(uri)
  except LPError as err:
    fatal "Invalid SignedPeerRecord uri", uri = uri, error = err.msg
    quit QuitFailure

proc readValue*(r: var TomlReader, val: var MultiAddress) =
  without input =? r.readValue(string).catch, err:
    error "invalid MultiAddress configuration value", error = err.msg
    quit QuitFailure

  let res = MultiAddress.init(input)
  if res.isOk:
    val = res.get()
  else:
    fatal "Invalid MultiAddress", input = input, error = res.error()
    quit QuitFailure

proc readValue*(
    r: var TomlReader, val: var NBytes
) {.raises: [SerializationError, IOError].} =
  var value = 0'i64
  var str = r.readValue(string)
  let count = parseSize(str, value, alwaysBin = true)
  if count == 0:
    error "invalid number of bytes for configuration value", value = str
    quit QuitFailure
  val = NBytes(value)

proc readValue*(
    r: var TomlReader, val: var ThreadCount
) {.raises: [SerializationError, IOError].} =
  var str = r.readValue(string)
  try:
    val = parseCmdArg(ThreadCount, str)
  except CatchableError as err:
    raise newException(SerializationError, err.msg)

proc readValue*(
    r: var TomlReader, val: var Duration
) {.raises: [SerializationError, IOError].} =
  var str = r.readValue(string)
  var dur: Duration
  let count = parseDuration(str, dur)
  if count == 0:
    error "Invalid duration parse", value = str
    quit QuitFailure
  val = dur

proc readValue*(
    r: var TomlReader, val: var NatConfig
) {.raises: [SerializationError].} =
  val =
    try:
      parseCmdArg(NatConfig, r.readValue(string))
    except CatchableError as err:
      raise newException(SerializationError, err.msg)

# no idea why confutils needs this:
proc completeCmdArg*(T: type NBytes, val: string): seq[string] =
  discard

proc completeCmdArg*(T: type Duration, val: string): seq[string] =
  discard

proc completeCmdArg*(T: type ThreadCount, val: string): seq[string] =
  discard

# silly chronicles, colors is a compile-time property
proc stripAnsi*(v: string): string =
  var
    res = newStringOfCap(v.len)
    i: int

  while i < v.len:
    let c = v[i]
    if c == '\x1b':
      var
        x = i + 1
        found = false

      while x < v.len: # look for [..m
        let c2 = v[x]
        if x == i + 1:
          if c2 != '[':
            break
        else:
          if c2 in {'0' .. '9'} + {';'}:
            discard # keep looking
          elif c2 == 'm':
            i = x + 1
            found = true
            break
          else:
            break
        inc x

      if found: # skip adding c
        continue
    res.add c
    inc i

  res

proc updateLogLevel*(logLevel: string) {.raises: [ValueError].} =
  # Updates log levels (without clearing old ones)
  let directives = logLevel.split(";")
  try:
    setLogLevel(parseEnum[LogLevel](directives[0].toUpperAscii))
  except ValueError:
    raise (ref ValueError)(
      msg:
        "Please specify one of: trace, debug, " & "info, notice, warn, error or fatal"
    )

  if directives.len > 1:
    for topicName, settings in parseTopicDirectives(directives[1 ..^ 1]):
      if not setTopicState(topicName, settings.state, settings.logLevel):
        warn "Unrecognized logging topic", topic = topicName

proc setupLogging*(conf: CodexConf) =
  when defaultChroniclesStream.outputs.type.arity != 3:
    warn "Logging configuration options not enabled in the current build"
  else:
    var logFile: ?IoHandle
    proc noOutput(logLevel: LogLevel, msg: LogOutputStr) =
      discard

    proc writeAndFlush(f: File, msg: LogOutputStr) =
      try:
        f.write(msg)
        f.flushFile()
      except IOError as err:
        logLoggingFailure(cstring(msg), err)

    proc stdoutFlush(logLevel: LogLevel, msg: LogOutputStr) =
      writeAndFlush(stdout, msg)

    proc noColorsFlush(logLevel: LogLevel, msg: LogOutputStr) =
      writeAndFlush(stdout, stripAnsi(msg))

    proc fileFlush(logLevel: LogLevel, msg: LogOutputStr) =
      if file =? logFile:
        if error =? file.writeFile(stripAnsi(msg).toBytes).errorOption:
          error "failed to write to log file", errorCode = $error

    defaultChroniclesStream.outputs[2].writer = noOutput
    if logFilePath =? conf.logFile and logFilePath.len > 0:
      let logFileHandle =
        openFile(logFilePath, {OpenFlags.Write, OpenFlags.Create, OpenFlags.Truncate})
      if logFileHandle.isErr:
        error "failed to open log file",
          path = logFilePath, errorCode = $logFileHandle.error
      else:
        logFile = logFileHandle.option
        defaultChroniclesStream.outputs[2].writer = fileFlush

    defaultChroniclesStream.outputs[1].writer = noOutput

    let writer =
      case conf.logFormat
      of LogKind.Auto:
        if isatty(stdout): stdoutFlush else: noColorsFlush
      of LogKind.Colors:
        stdoutFlush
      of LogKind.NoColors:
        noColorsFlush
      of LogKind.Json:
        defaultChroniclesStream.outputs[1].writer = stdoutFlush
        noOutput
      of LogKind.None:
        noOutput

    when storage_enable_log_counter:
      var counter = 0.uint64
      proc numberedWriter(logLevel: LogLevel, msg: LogOutputStr) =
        inc(counter)
        let withoutNewLine = msg[0 ..^ 2]
        writer(logLevel, withoutNewLine & " count=" & $counter & "\n")

      defaultChroniclesStream.outputs[0].writer = numberedWriter
    else:
      defaultChroniclesStream.outputs[0].writer = writer

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