# Nimbus
# Copyright (c) 2018 Status Research & Development GmbH
# Licensed under either of
#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed except according to those terms.

import
  os, macros, json, strformat, strutils, parseutils, os, tables,
  stew/byteutils, net, eth/[common, keys, rlp, p2p], unittest2,
  testutils/markdown_reports,
  ../nimbus/[config, transaction, utils, errors],
  ../nimbus/vm/interpreter/vm_forks,
  ../nimbus/db/accounts_cache,
  ../nimbus/random_keys

func revmap(x: Table[Fork, string]): Table[string, Fork] =
  result = initTable[string, Fork]()
  for k, v in x:
    result[v] = k

const
  # from https://ethereum-tests.readthedocs.io/en/latest/test_types/state_tests.html
  forkNames* = {
    FkFrontier: "Frontier",
    FkHomestead: "Homestead",
    FkTangerine: "EIP150",
    FkSpurious: "EIP158",
    FkByzantium: "Byzantium",
    FkConstantinople: "Constantinople",
    FkPetersburg: "ConstantinopleFix",
    FkIstanbul: "Istanbul",
    FkBerlin: "Berlin"
  }.toTable

  supportedForks* = {
    FkFrontier,
    FkHomestead,
    FkTangerine,
    FkSpurious,
    FkByzantium,
    FkConstantinople,
    FkPetersburg,
    FkIstanbul,
    FkBerlin}

  nameToFork* = revmap(forkNames)

func skipNothing*(folder: string, name: string): bool = false

proc lacksSupportedForks*(fixtures: JsonNode): bool =
  # XXX: Until Nimbus supports all forks, some of the GeneralStateTests won't work.

  var fixture: JsonNode
  for label, child in fixtures:
    fixture = child
    break

  # not all fixtures make a distinction between forks, so default to accepting
  # them all, until we find the ones that specify forks in their "post" section
  result = false
  if fixture.kind == JObject and fixture.hasKey("transaction") and fixture.hasKey("post"):
    result = true
    for fork in supportedForks:
      if fixture["post"].hasKey(forkNames[fork]):
        result = false
        break

var status = initOrderedTable[string, OrderedTable[string, Status]]()

proc jsonTestImpl*(inputFolder, outputName: string, handler, skipTest: NimNode): NimNode {.compileTime.} =
  let
    testStatusIMPL = ident("testStatusIMPL")
    testName = ident("testName")
    # workaround for strformat in quote do: https://github.com/nim-lang/Nim/issues/8220
    symbol {.used.} = newIdentNode"symbol"
    final  {.used.} = newIdentNode"final"
    name   {.used.} = newIdentNode"name"
    formatted {.used.} = newStrLitNode"{symbol[final]} {name:<64}{$final}{'\n'}"

  result = quote:
    var filenames: seq[string] = @[]
    for filename in walkDirRec("tests" / "fixtures" / `inputFolder`):
      if not filename.endsWith(".json"):
        continue
      var (folder, name) = filename.splitPath()
      let last = folder.splitPath().tail
      if not status.hasKey(last):
        status[last] = initOrderedTable[string, Status]()
      status[last][name] = Status.Skip
      if `skipTest`(last, name):
        continue
      filenames.add(filename)
    for fname in filenames:
      test fname:
        {.gcsafe.}:
          let
            filename = `testName` # the first argument passed to the `test` template
            (folder, name) = filename.splitPath()
            last = folder.splitPath().tail
          # we set this here because exceptions might be raised in the handler:
          status[last][name] = Status.Fail
          let fixtures = parseJSON(readFile(filename))
          if fixtures.lacksSupportedForks:
            status[last][name] = Status.Skip
            skip()
          else:
            # when not paralleliseTests:
            #   echo filename
            `handler`(fixtures, `testStatusIMPL`)
            if `testStatusIMPL` == OK:
              status[last][name] = Status.OK

    suiteTeardown:
      status.sort do (a: (string, OrderedTable[string, Status]),
                      b: (string, OrderedTable[string, Status])) -> int: cmp(a[0], b[0])

      generateReport(`outputName`, status)
      status.clear()

macro jsonTest*(inputFolder, outputName: static[string], handler: untyped, skipTest: untyped = skipNothing): untyped =
  result = jsonTestImpl(inputFolder, outputName, handler, skipTest)

macro jsonTest*(inputFolder: static[string], handler: untyped, skipTest: untyped = skipNothing): untyped =
  result = jsonTestImpl(inputFolder, inputFolder, handler, skipTest)

func ethAddressFromHex*(s: string): EthAddress = hexToByteArray(s, result)

func safeHexToSeqByte*(hexStr: string): seq[byte] =
  if hexStr == "":
    @[]
  else:
    hexStr.hexToSeqByte

func getHexadecimalInt*(j: JsonNode): int64 =
  # parseutils.parseHex works with int which will overflow in 32 bit
  var data: StUInt[64]
  data = fromHex(StUInt[64], j.getStr)
  result = cast[int64](data)

proc setupStateDB*(wantedState: JsonNode, stateDB: var AccountsCache) =
  for ac, accountData in wantedState:
    let account = ethAddressFromHex(ac)
    for slot, value in accountData{"storage"}:
      stateDB.setStorage(account, fromHex(UInt256, slot), fromHex(UInt256, value.getStr))

    let nonce = accountData{"nonce"}.getHexadecimalInt.AccountNonce
    let code = accountData{"code"}.getStr.safeHexToSeqByte
    let balance = UInt256.fromHex accountData{"balance"}.getStr

    stateDB.setNonce(account, nonce)
    stateDB.setCode(account, code)
    stateDB.setBalance(account, balance)

proc verifyStateDB*(wantedState: JsonNode, stateDB: ReadOnlyStateDB) =
  for ac, accountData in wantedState:
    let account = ethAddressFromHex(ac)
    for slot, value in accountData{"storage"}:
      let
        slotId = UInt256.fromHex slot
        wantedValue = UInt256.fromHex value.getStr

      let actualValue = stateDB.getStorage(account, slotId)
      #if not found:
      #  raise newException(ValidationError, "account not found:  " & ac)
      if actualValue != wantedValue:
        raise newException(ValidationError, &"{ac} storageDiff: [{slot}] {actualValue.toHex} != {wantedValue.toHex}")

    let
      wantedCode = hexToSeqByte(accountData{"code"}.getStr)
      wantedBalance = UInt256.fromHex accountData{"balance"}.getStr
      wantedNonce = accountData{"nonce"}.getHexadecimalInt.AccountNonce

      actualCode = stateDB.getCode(account)
      actualBalance = stateDB.getBalance(account)
      actualNonce = stateDB.getNonce(account)

    if wantedCode != actualCode:
      raise newException(ValidationError, &"{ac} codeDiff {wantedCode.toHex} != {actualCode.toHex}")
    if wantedBalance != actualBalance:
      raise newException(ValidationError, &"{ac} balanceDiff {wantedBalance.toHex} != {actualBalance.toHex}")
    if wantedNonce != actualNonce:
      raise newException(ValidationError, &"{ac} nonceDiff {wantedNonce.toHex} != {actualNonce.toHex}")

proc getFixtureTransaction*(j: JsonNode, dataIndex, gasIndex, valueIndex: int): Transaction =
  result.accountNonce = j["nonce"].getHexadecimalInt.AccountNonce
  result.gasPrice = j["gasPrice"].getHexadecimalInt
  result.gasLimit = j["gasLimit"][gasIndex].getHexadecimalInt

  # TODO: there are a couple fixtures which appear to distinguish between
  # empty and 0 transaction.to; check/verify whether correct conditions.
  let rawTo = j["to"].getStr
  if rawTo == "":
    result.to = "0x".parseAddress
    result.isContractCreation = true
  else:
    result.to = rawTo.parseAddress
    result.isContractCreation = false
  result.value = fromHex(UInt256, j["value"][valueIndex].getStr)
  result.payload = j["data"][dataIndex].getStr.safeHexToSeqByte

  var secretKey = j["secretKey"].getStr
  removePrefix(secretKey, "0x")
  let privateKey = PrivateKey.fromHex(secretKey).tryGet()
  let sig = sign(privateKey, result.rlpEncode)
  let raw = sig.toRaw()

  result.R = fromBytesBE(Uint256, raw[0..31])
  result.S = fromBytesBE(Uint256, raw[32..63])
  result.V = raw[64] + 27.byte

proc hashLogEntries*(logs: seq[Log]): string =
  toLowerAscii("0x" & $keccakHash(rlp.encode(logs)))

proc setupEthNode*(capabilities: varargs[ProtocolInfo, `protocolInfo`]): EthereumNode =
  var conf = getConfiguration()
  conf.net.nodekey = randomPrivateKey()
  let keypair = conf.net.nodekey.toKeyPair()

  var srvAddress: Address
  srvAddress.ip = parseIpAddress("0.0.0.0")
  srvAddress.tcpPort = Port(conf.net.bindPort)
  srvAddress.udpPort = Port(conf.net.discPort)
  result = newEthereumNode(
    keypair, srvAddress, conf.net.networkId, nil, "nimbus 0.1.0",
    addAllCapabilities = false)
  for capability in capabilities:
    result.addCapability capability