Pack.hs

-- | Module, carrying logic of @PACK@ instruction.
--
-- This is nearly symmetric to adjacent Unpack.hs module.
module Michelson.Interpret.Pack
  ( packCode'
  , packT'
  , packValue
  , packValue'

    -- * Internals
  , encodeIntPayload
  ) where

import Prelude hiding (EQ, GT, LT)

import Control.Exception (assert)
import qualified Data.Binary.Put as Bi
import qualified Data.Bits as Bits
import qualified Data.ByteArray as ByteArray
import qualified Data.ByteString.Lazy as LBS
import qualified Data.Map as Map
import Data.Singletons (SingI(..))

import Michelson.Text
import Michelson.Typed
import Tezos.Address (Address(..), ContractHash(..))
import Tezos.Core (ChainId(..), Mutez(..), timestampToSeconds)
import Tezos.Crypto (KeyHash(..), KeyHashTag(..), PublicKey(..), signatureToBytes)
import qualified Tezos.Crypto.Ed25519 as Ed25519
import qualified Tezos.Crypto.P256 as P256
import qualified Tezos.Crypto.Secp256k1 as Secp256k1
import Util.Peano (peanoValSing)

-- | Serialize a value given to @PACK@ instruction.
packValue :: PackedValScope t => Value t -> LByteString
packValue x = "\x05" <> encodeValue x

-- | Same as 'packValue', for strict bytestring.
packValue' :: PackedValScope t => Value t -> ByteString
packValue' = LBS.toStrict . packValue

packT' :: forall (t :: T). SingI t => ByteString
packT' = LBS.toStrict $ encodeT' @t

packCode' :: Instr inp out -> ByteString
packCode' = LBS.toStrict . encodeInstrs

surround :: LByteString -> LByteString -> ByteString -> LByteString
surround prefix suffix main = prefix <> LBS.fromStrict main <> suffix

encodeValue :: forall t. PackedValScope t => Value t -> LByteString
encodeValue val = case (val, sing @t) of
  (VC cval, _) -> encodeCValue cval
  (VKey s, _) -> encodeBytes . LBS.fromStrict $ case s of
    PublicKeyEd25519 pk -> "\x00" <> Ed25519.publicKeyToBytes pk
    PublicKeySecp256k1 pk -> "\x01" <> Secp256k1.publicKeyToBytes pk
    PublicKeyP256 pk -> "\x02" <> P256.publicKeyToBytes pk
  (VUnit, _) -> "\x03\x0b"
  (VSignature x, _) -> encodeBytes . LBS.fromStrict $ signatureToBytes x
  (VChainId x, _) ->
    encodeBytes . LBS.fromStrict $
      ByteArray.convert (unChainId x)
  (VOption (Just x), STOption _) -> "\x05\x09" <> encodeValue x
  (VOption Nothing, _) -> "\x03\x06"
  (VList xs, STList _) -> encodeList encodeValue xs
  (VSet xs, _) -> encodeList encodeCValue (toList xs)
  (VContract addr sepc, _) -> encodeEpAddress $ EpAddress addr (sepcName sepc)
  (VPair (v1, v2), STPair l _) ->
    case (checkOpPresence l, checkBigMapPresence l) of
      (OpAbsent, BigMapAbsent) -> "\x07\x07" <> encodeValue v1 <> encodeValue v2
  (VOr (Left v), STOr l _) ->
    case (checkOpPresence l, checkBigMapPresence l) of
      (OpAbsent, BigMapAbsent) -> "\x05\x05" <> encodeValue v
  (VOr (Right v), STOr l _) ->
    case (checkOpPresence l, checkBigMapPresence l) of
      (OpAbsent, BigMapAbsent) -> "\x05\x08" <> encodeValue v
  (VLam lam, _) -> encodeInstrs $ rfAnyInstr lam
  (VMap m, STMap _ _) -> encodeMap m

encodeCValue :: CValue t -> LByteString
encodeCValue = \case
  CvInt x        -> encodeNumeric x
  CvNat x        -> encodeNumeric x
  CvString text  -> encodeString text
  CvBytes bytes  -> encodeBytes (LBS.fromStrict bytes)
  CvMutez x      -> encodeNumeric (unMutez x)
  CvBool True    -> "\x03\x0a"
  CvBool False   -> "\x03\x03"
  CvKeyHash kh   -> encodeBytes $ encodeKeyHashRaw kh
  CvTimestamp x  -> encodeNumeric (timestampToSeconds @Integer x)
  CvAddress addr -> encodeEpAddress addr

encodeLength :: Int -> LByteString
encodeLength = Bi.runPut . Bi.putWord32be . fromIntegral

-- | Lift encoded list content to an entire encoded list.
encodeAsList :: LByteString -> LByteString
encodeAsList bs = encodeLength (length bs) <> bs

-- | Encode a list-like structure.
encodeList :: (a -> LByteString) -> [a] -> LByteString
encodeList encodeElem l = "\x02" <> encodeAsList (LBS.concat $ map encodeElem l)

-- | Encode a text.
encodeString :: MText -> LByteString
encodeString text = "\x01" <> encodeAsList (encodeUtf8 $ unMText text)

-- | Encode some raw data.
encodeBytes :: LByteString -> LByteString
encodeBytes bs =
  "\x0a" <> encodeAsList bs

-- TODO [TM-293]: Probably encode via converting to annotation first
encodeEpName :: EpName -> LByteString
encodeEpName = encodeUtf8 . unEpName

-- | Encode some map.
encodeMap :: (PackedValScope v) => Map (CValue k) (Value v) -> LByteString
encodeMap m =
  encodeList (\(k, v) -> "\x07\x04" <> encodeCValue k <> encodeValue v) (Map.toList m)

encodeKeyHashRaw :: KeyHash -> LByteString
encodeKeyHashRaw kh = (<> LBS.fromStrict (khBytes kh)) $
  case khTag kh of
    KeyHashEd25519 -> "\x00"
    KeyHashSecp256k1 -> "\x01"
    KeyHashP256 -> "\x02"

encodeAddress :: Address -> LByteString
encodeAddress = \case
  KeyAddress keyHash -> "\x00" <> (encodeKeyHashRaw keyHash)
  ContractAddress (ContractHash address) -> surround "\x01" "\x00" address

encodeEpAddress :: EpAddress -> LByteString
encodeEpAddress (EpAddress addr epName) =
  encodeBytes $ encodeAddress addr <> encodeEpName epName

-- | Encode contents of a given number.
encodeIntPayload :: Integer -> LByteString
encodeIntPayload = LBS.pack . toList . doEncode True
  where
    {- Numbers are represented as follows:

    byte 0:         1              _         ______   ||  lowest digits
            has continuation  is negative   payload   ||
                                                      ||
    byte 1:         1                       _______   ||
    ...             1                       _______   ||
    byte n:         0                       _______   ||
            has continuation                payload   \/  highest digits
    -}
    doEncode :: Bool -> Integer -> NonEmpty Word8
    doEncode isFirst a
      | a >= byteWeight =
          let (hi, lo) = a `divMod` byteWeight
              byte = Bits.setBit (fromIntegral @_ @Word8 lo) 7
          in byte :| toList (doEncode False hi)
      | a >= 0 =
          one (fromIntegral @_ @Word8 a)
      | otherwise = assert isFirst $
          let h :| t = doEncode True (-a)
          in Bits.setBit h 6 :| t
      where
        byteWeight = if isFirst then 64 else 128

-- | Encode an int-like value.
encodeNumeric :: Integral i => i -> LByteString
encodeNumeric i = "\x00" <> encodeIntPayload (fromIntegral i)

-- | Encode a code block.
encodeInstrs :: Instr inp out -> LByteString
encodeInstrs = encodeList id . one . encodeInstr

-- | Encode an instruction.
encodeInstr :: forall inp out. Instr inp out -> LByteString
encodeInstr = \case
  InstrWithNotes _ a -> encodeInstr a
  FrameInstr _ i ->
    encodeInstr i
  Seq a b ->
    encodeInstr a <> encodeInstr b
  Nop ->
    mempty
  Nested i ->
    encodeInstrs i
  DocGroup _ i ->
    encodeInstrs i
  Ext _ ->
    ""
  DROP ->
    "\x03\x20"
  DROPN s ->
    "\x05\x20" <> encodeNumeric (peanoValSing s)
  DUP ->
    "\x03\x21"
  SWAP ->
    "\x03\x4c"
  DIG s ->
    "\x05\x70" <> encodeNumeric (peanoValSing s)
  DUG s ->
    "\x05\x71" <> encodeNumeric (peanoValSing s)
  PUSH (a :: Value t) ->
    "\x07\x43" <> encodeT' @t <> encodeValue a
  SOME ->
    "\x03\x46"
  NONE | _ :: Proxy ('TOption t ': s) <- Proxy @out ->
    "\x05\x3e" <> encodeT' @t
  UNIT ->
    "\x03\x4f"
  IF_NONE a b ->
    "\x07\x2f" <> encodeInstrs a <> encodeInstrs b
  PAIR ->
    "\x03\x42"
  (AnnCAR _) ->
    "\x03\x16"
  (AnnCDR _) ->
    "\x03\x17"
  LEFT | _ :: Proxy ('TOr l r ': s) <- Proxy @out ->
    "\x05\x33" <> encodeT' @r
  RIGHT | _ :: Proxy ('TOr l r ': s) <- Proxy @out ->
    "\x05\x44" <> encodeT' @l
  IF_LEFT a b ->
    "\x07\x2e" <> encodeInstrs a <> encodeInstrs b
  NIL | _ :: Proxy ('TList t ': s) <- Proxy @out ->
    "\x05\x3d" <> encodeT' @t
  CONS ->
    "\x03\x1b"
  IF_CONS a b ->
    "\x07\x2d" <> encodeInstrs a <> encodeInstrs b
  SIZE ->
    "\x03\x45"
  EMPTY_SET | _ :: Proxy ('TSet t ': s) <- Proxy @out ->
    "\x05\x24" <> encodeT' @('Tc t)
  EMPTY_MAP | _ :: Proxy ('TMap k v ': s) <- Proxy @out ->
    "\x07\x23" <> encodeT' @('Tc k) <> encodeT' @v
  EMPTY_BIG_MAP | _ :: Proxy ('TBigMap k v ': s) <- Proxy @out ->
    "\x07\x72" <> encodeT' @('Tc k) <> encodeT' @v
  MAP a ->
    "\x05\x38" <> encodeInstrs a
  ITER a ->
    "\x05\x52" <> encodeInstrs a
  MEM ->
    "\x03\x39"
  GET ->
    "\x03\x29"
  UPDATE ->
    "\x03\x50"
  IF a b ->
    "\x07\x2c" <> encodeInstrs a <> encodeInstrs b
  LOOP a ->
    "\x05\x34" <> encodeInstrs a
  LOOP_LEFT a ->
    "\x05\x53" <> encodeInstrs a
  LAMBDA (v :: Value ('TLambda i o)) ->
    "\x09\x31" <>
    encodeAsList (encodeT' @i <> encodeT' @o <> encodeValue v) <>
    encodeLength 0  -- @martoon: dunno where does it come from
  EXEC ->
    "\x03\x26"
  APPLY ->
    "\x03\x73"
  DIP a ->
    "\x05\x1f" <> encodeInstrs a
  DIPN s a ->
    "\x07\x1f" <> encodeNumeric (peanoValSing s) <> encodeInstrs a
  FAILWITH ->
    "\x03\x27"
  CAST | _ :: Proxy (t ': s) <- Proxy @out ->
    "\x05\x57" <> encodeT' @t
  RENAME ->
    "\x03\x58"
  PACK ->
    "\x03\x0c"
  UNPACK | _ :: Proxy ('TOption t ': s) <- Proxy @out ->
    "\x05\x0d" <> encodeT' @t
  CONCAT ->
    "\x03\x1a"
  CONCAT' ->
    "\x03\x1a"
  SLICE ->
    "\x03\x6f"
  ISNAT ->
    "\x03\x56"
  ADD ->
    "\x03\x12"
  SUB ->
    "\x03\x4b"
  MUL ->
    "\x03\x3a"
  EDIV ->
    "\x03\x22"
  ABS ->
    "\x03\x11"
  NEG ->
    "\x03\x3b"
  LSL ->
    "\x03\x35"
  LSR ->
    "\x03\x36"
  OR ->
    "\x03\x41"
  AND ->
    "\x03\x14"
  XOR ->
    "\x03\x51"
  NOT ->
    "\x03\x3f"
  COMPARE ->
    "\x03\x19"
  EQ ->
    "\x03\x25"
  NEQ ->
    "\x03\x3c"
  LT ->
    "\x03\x37"
  GT ->
    "\x03\x2a"
  LE ->
    "\x03\x32"
  GE ->
    "\x03\x28"
  INT ->
    "\x03\x30"
  SELF ->
    error "SELF should not appear in lambda"
  -- TODO [TM-336]: encode annotation here
  CONTRACT _ _ | _ :: Proxy ('TOption ('TContract t) ': s) <- Proxy @out ->
    "\x05\x55" <> encodeT' @t
  TRANSFER_TOKENS ->
    "\x03\x4d"
  SET_DELEGATE ->
    "\x03\x4e"
  CREATE_CONTRACT (FullContract instr _ _)
    | _ :: Instr '[ 'TPair p g ] '[ 'TPair ('TList 'TOperation) g ] <- instr ->
    let contents =
          [ "\x05\x00" <> encodeT' @p
          , "\x05\x01" <> encodeT' @g
          , "\x05\x02" <> encodeInstrs instr
          ]
    -- TODO [TM-96] These ^ should be encoded in the same order in which
    -- they appear in the original code
    in "\x05\x1d" <> encodeList id contents
  IMPLICIT_ACCOUNT ->
   "\x03\x1e"
  NOW ->
   "\x03\x40"
  AMOUNT ->
   "\x03\x13"
  BALANCE ->
   "\x03\x15"
  CHECK_SIGNATURE ->
   "\x03\x18"
  SHA256 ->
   "\x03\x0f"
  SHA512 ->
   "\x03\x10"
  BLAKE2B ->
   "\x03\x0e"
  HASH_KEY ->
   "\x03\x2b"
  STEPS_TO_QUOTA ->
   "\x03\x4a"
  SOURCE ->
   "\x03\x47"
  SENDER ->
   "\x03\x48"
  ADDRESS ->
   "\x03\x54"
  CHAIN_ID ->
   "\x03\x75"

encodeT :: T -> LByteString
encodeT = \case
  Tc ct -> encodeCT ct
  TKey  -> "\x03\x5c"
  TUnit -> "\x03\x6c"
  TSignature -> "\x03\x67"
  TChainId -> "\x03\x74"
  TOption t -> "\x05\x63" <> encodeT t
  TList t -> "\x05\x5f" <> encodeT t
  TSet t -> "\x05\x66" <> encodeCT t
  TOperation -> "\x03\x6d"
  TContract t -> "\x05\x5a" <> encodeT t
  TPair a b -> "\x07\x65" <> encodeT a <> encodeT b
  TOr a b -> "\x07\x64" <> encodeT a <> encodeT b
  TLambda a r -> "\x07\x5e" <> encodeT a <> encodeT r
  TMap k v -> "\x07\x60" <> encodeCT k <> encodeT v
  TBigMap k v -> "\x07\x61" <> encodeCT k <> encodeT v

encodeT' :: forall (t :: T). SingI t => LByteString
encodeT' = encodeT (fromSingT $ sing @t)

encodeCT :: CT -> LByteString
encodeCT = ("\x03" <>) . \case
  CInt -> "\x5b"
  CNat -> "\x62"
  CString -> "\x68"
  CBytes -> "\x69"
  CMutez -> "\x6a"
  CBool -> "\x59"
  CKeyHash -> "\x5d"
  CTimestamp -> "\x6b"
  CAddress -> "\x6e"