{-# LANGUAGE DeriveAnyClass #-}
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE OverloadedStrings #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}

{- |
Module      : Haskoin.Keys.Common
Copyright   : No rights reserved
License     : MIT
Maintainer  : jprupp@protonmail.ch
Stability   : experimental
Portability : POSIX

ECDSA private and public key functions.
-}
module Haskoin.Keys.Common (
    -- * Public & Private Keys
    PubKeyI (..),
    SecKeyI (..),
    exportPubKey,
    importPubKey,
    wrapPubKey,
    derivePubKeyI,
    wrapSecKey,
    fromMiniKey,
    tweakPubKey,
    tweakSecKey,
    getSecKey,
    secKey,

    -- ** Private Key Wallet Import Format (WIF)
    fromWif,
    toWif,
) where

import Control.DeepSeq
import Control.Monad (guard, mzero, (<=<))
import Crypto.Secp256k1
import Data.Aeson (
    FromJSON,
    ToJSON (..),
    Value (String),
    parseJSON,
    withText,
 )
import Data.Aeson.Encoding (unsafeToEncoding)
import Data.Binary (Binary (..))
import Data.ByteString (ByteString)
import qualified Data.ByteString as BS
import Data.ByteString.Builder (char7)
import Data.Bytes.Get
import Data.Bytes.Put
import Data.Bytes.Serial
import Data.Hashable
import Data.Maybe (fromMaybe)
import Data.Serialize (Serialize (..))
import Data.String (IsString, fromString)
import Data.String.Conversions (cs)
import GHC.Generics (Generic)
import Haskoin.Address.Base58
import Haskoin.Crypto.Hash
import Haskoin.Data
import Haskoin.Util

-- | Elliptic curve public key type with expected serialized compression flag.
data PubKeyI = PubKeyI
    { PubKeyI -> PubKey
pubKeyPoint :: !PubKey
    , PubKeyI -> Bool
pubKeyCompressed :: !Bool
    }
    deriving ((forall x. PubKeyI -> Rep PubKeyI x)
-> (forall x. Rep PubKeyI x -> PubKeyI) -> Generic PubKeyI
forall x. Rep PubKeyI x -> PubKeyI
forall x. PubKeyI -> Rep PubKeyI x
forall a.
(forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a
$cto :: forall x. Rep PubKeyI x -> PubKeyI
$cfrom :: forall x. PubKeyI -> Rep PubKeyI x
Generic, PubKeyI -> PubKeyI -> Bool
(PubKeyI -> PubKeyI -> Bool)
-> (PubKeyI -> PubKeyI -> Bool) -> Eq PubKeyI
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: PubKeyI -> PubKeyI -> Bool
$c/= :: PubKeyI -> PubKeyI -> Bool
== :: PubKeyI -> PubKeyI -> Bool
$c== :: PubKeyI -> PubKeyI -> Bool
Eq, Int -> PubKeyI -> ShowS
[PubKeyI] -> ShowS
PubKeyI -> String
(Int -> PubKeyI -> ShowS)
-> (PubKeyI -> String) -> ([PubKeyI] -> ShowS) -> Show PubKeyI
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [PubKeyI] -> ShowS
$cshowList :: [PubKeyI] -> ShowS
show :: PubKeyI -> String
$cshow :: PubKeyI -> String
showsPrec :: Int -> PubKeyI -> ShowS
$cshowsPrec :: Int -> PubKeyI -> ShowS
Show, ReadPrec [PubKeyI]
ReadPrec PubKeyI
Int -> ReadS PubKeyI
ReadS [PubKeyI]
(Int -> ReadS PubKeyI)
-> ReadS [PubKeyI]
-> ReadPrec PubKeyI
-> ReadPrec [PubKeyI]
-> Read PubKeyI
forall a.
(Int -> ReadS a)
-> ReadS [a] -> ReadPrec a -> ReadPrec [a] -> Read a
readListPrec :: ReadPrec [PubKeyI]
$creadListPrec :: ReadPrec [PubKeyI]
readPrec :: ReadPrec PubKeyI
$creadPrec :: ReadPrec PubKeyI
readList :: ReadS [PubKeyI]
$creadList :: ReadS [PubKeyI]
readsPrec :: Int -> ReadS PubKeyI
$creadsPrec :: Int -> ReadS PubKeyI
Read, Int -> PubKeyI -> Int
PubKeyI -> Int
(Int -> PubKeyI -> Int) -> (PubKeyI -> Int) -> Hashable PubKeyI
forall a. (Int -> a -> Int) -> (a -> Int) -> Hashable a
hash :: PubKeyI -> Int
$chash :: PubKeyI -> Int
hashWithSalt :: Int -> PubKeyI -> Int
$chashWithSalt :: Int -> PubKeyI -> Int
Hashable, PubKeyI -> ()
(PubKeyI -> ()) -> NFData PubKeyI
forall a. (a -> ()) -> NFData a
rnf :: PubKeyI -> ()
$crnf :: PubKeyI -> ()
NFData)

instance IsString PubKeyI where
    fromString :: String -> PubKeyI
fromString String
str =
        PubKeyI -> Maybe PubKeyI -> PubKeyI
forall a. a -> Maybe a -> a
fromMaybe PubKeyI
forall a. a
e (Maybe PubKeyI -> PubKeyI) -> Maybe PubKeyI -> PubKeyI
forall a b. (a -> b) -> a -> b
$ Either String PubKeyI -> Maybe PubKeyI
forall a b. Either a b -> Maybe b
eitherToMaybe (Either String PubKeyI -> Maybe PubKeyI)
-> (ByteString -> Either String PubKeyI)
-> ByteString
-> Maybe PubKeyI
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Get PubKeyI -> ByteString -> Either String PubKeyI
forall a. Get a -> ByteString -> Either String a
runGetS Get PubKeyI
forall a (m :: * -> *). (Serial a, MonadGet m) => m a
deserialize (ByteString -> Maybe PubKeyI)
-> (Text -> Maybe ByteString) -> Text -> Maybe PubKeyI
forall (m :: * -> *) b c a.
Monad m =>
(b -> m c) -> (a -> m b) -> a -> m c
<=< Text -> Maybe ByteString
decodeHex (Text -> Maybe PubKeyI) -> Text -> Maybe PubKeyI
forall a b. (a -> b) -> a -> b
$ String -> Text
forall a b. ConvertibleStrings a b => a -> b
cs String
str
      where
        e :: a
e = String -> a
forall a. HasCallStack => String -> a
error String
"Could not decode public key"

instance ToJSON PubKeyI where
    toJSON :: PubKeyI -> Value
toJSON = Text -> Value
String (Text -> Value) -> (PubKeyI -> Text) -> PubKeyI -> Value
forall b c a. (b -> c) -> (a -> b) -> a -> c
. ByteString -> Text
encodeHex (ByteString -> Text) -> (PubKeyI -> ByteString) -> PubKeyI -> Text
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Put -> ByteString
runPutS (Put -> ByteString) -> (PubKeyI -> Put) -> PubKeyI -> ByteString
forall b c a. (b -> c) -> (a -> b) -> a -> c
. PubKeyI -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize
    toEncoding :: PubKeyI -> Encoding
toEncoding PubKeyI
s =
        Builder -> Encoding
forall a. Builder -> Encoding' a
unsafeToEncoding (Builder -> Encoding) -> Builder -> Encoding
forall a b. (a -> b) -> a -> b
$
            Char -> Builder
char7 Char
'"'
                Builder -> Builder -> Builder
forall a. Semigroup a => a -> a -> a
<> ByteString -> Builder
hexBuilder (Put -> ByteString
runPutL (PubKeyI -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize PubKeyI
s))
                Builder -> Builder -> Builder
forall a. Semigroup a => a -> a -> a
<> Char -> Builder
char7 Char
'"'

instance FromJSON PubKeyI where
    parseJSON :: Value -> Parser PubKeyI
parseJSON =
        String -> (Text -> Parser PubKeyI) -> Value -> Parser PubKeyI
forall a. String -> (Text -> Parser a) -> Value -> Parser a
withText String
"PubKeyI" ((Text -> Parser PubKeyI) -> Value -> Parser PubKeyI)
-> (Text -> Parser PubKeyI) -> Value -> Parser PubKeyI
forall a b. (a -> b) -> a -> b
$
            Parser PubKeyI
-> (PubKeyI -> Parser PubKeyI) -> Maybe PubKeyI -> Parser PubKeyI
forall b a. b -> (a -> b) -> Maybe a -> b
maybe Parser PubKeyI
forall (m :: * -> *) a. MonadPlus m => m a
mzero PubKeyI -> Parser PubKeyI
forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe PubKeyI -> Parser PubKeyI)
-> (Text -> Maybe PubKeyI) -> Text -> Parser PubKeyI
forall b c a. (b -> c) -> (a -> b) -> a -> c
. ((Either String PubKeyI -> Maybe PubKeyI
forall a b. Either a b -> Maybe b
eitherToMaybe (Either String PubKeyI -> Maybe PubKeyI)
-> (ByteString -> Either String PubKeyI)
-> ByteString
-> Maybe PubKeyI
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Get PubKeyI -> ByteString -> Either String PubKeyI
forall a. Get a -> ByteString -> Either String a
runGetS Get PubKeyI
forall a (m :: * -> *). (Serial a, MonadGet m) => m a
deserialize) (ByteString -> Maybe PubKeyI)
-> (Text -> Maybe ByteString) -> Text -> Maybe PubKeyI
forall (m :: * -> *) b c a.
Monad m =>
(b -> m c) -> (a -> m b) -> a -> m c
<=< Text -> Maybe ByteString
decodeHex)

instance Serial PubKeyI where
    deserialize :: m PubKeyI
deserialize =
        m Bool
s m Bool -> (Bool -> m PubKeyI) -> m PubKeyI
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \case
            Bool
True -> m PubKeyI
c
            Bool
False -> m PubKeyI
u
      where
        s :: m Bool
s =
            m Bool -> m Bool
forall (m :: * -> *) a. MonadGet m => m a -> m a
lookAhead (m Bool -> m Bool) -> m Bool -> m Bool
forall a b. (a -> b) -> a -> b
$
                m Word8
forall (m :: * -> *). MonadGet m => m Word8
getWord8 m Word8 -> (Word8 -> m Bool) -> m Bool
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \case
                    Word8
0x02 -> Bool -> m Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
                    Word8
0x03 -> Bool -> m Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
                    Word8
0x04 -> Bool -> m Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
                    Word8
_ -> String -> m Bool
forall (m :: * -> *) a. MonadFail m => String -> m a
fail String
"Not a public key"
        c :: m PubKeyI
c = do
            ByteString
bs <- Int -> m ByteString
forall (m :: * -> *). MonadGet m => Int -> m ByteString
getByteString Int
33
            m PubKeyI -> (PubKeyI -> m PubKeyI) -> Maybe PubKeyI -> m PubKeyI
forall b a. b -> (a -> b) -> Maybe a -> b
maybe (String -> m PubKeyI
forall (m :: * -> *) a. MonadFail m => String -> m a
fail String
"Could not decode public key") PubKeyI -> m PubKeyI
forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe PubKeyI -> m PubKeyI) -> Maybe PubKeyI -> m PubKeyI
forall a b. (a -> b) -> a -> b
$
                PubKey -> Bool -> PubKeyI
PubKeyI (PubKey -> Bool -> PubKeyI)
-> Maybe PubKey -> Maybe (Bool -> PubKeyI)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ByteString -> Maybe PubKey
importPubKey ByteString
bs Maybe (Bool -> PubKeyI) -> Maybe Bool -> Maybe PubKeyI
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> Bool -> Maybe Bool
forall (f :: * -> *) a. Applicative f => a -> f a
pure Bool
True
        u :: m PubKeyI
u = do
            ByteString
bs <- Int -> m ByteString
forall (m :: * -> *). MonadGet m => Int -> m ByteString
getByteString Int
65
            m PubKeyI -> (PubKeyI -> m PubKeyI) -> Maybe PubKeyI -> m PubKeyI
forall b a. b -> (a -> b) -> Maybe a -> b
maybe (String -> m PubKeyI
forall (m :: * -> *) a. MonadFail m => String -> m a
fail String
"Could not decode public key") PubKeyI -> m PubKeyI
forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe PubKeyI -> m PubKeyI) -> Maybe PubKeyI -> m PubKeyI
forall a b. (a -> b) -> a -> b
$
                PubKey -> Bool -> PubKeyI
PubKeyI (PubKey -> Bool -> PubKeyI)
-> Maybe PubKey -> Maybe (Bool -> PubKeyI)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ByteString -> Maybe PubKey
importPubKey ByteString
bs Maybe (Bool -> PubKeyI) -> Maybe Bool -> Maybe PubKeyI
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> Bool -> Maybe Bool
forall (f :: * -> *) a. Applicative f => a -> f a
pure Bool
False

    serialize :: PubKeyI -> m ()
serialize PubKeyI
pk = ByteString -> m ()
forall (m :: * -> *). MonadPut m => ByteString -> m ()
putByteString (ByteString -> m ()) -> ByteString -> m ()
forall a b. (a -> b) -> a -> b
$ Bool -> PubKey -> ByteString
exportPubKey (PubKeyI -> Bool
pubKeyCompressed PubKeyI
pk) (PubKeyI -> PubKey
pubKeyPoint PubKeyI
pk)

instance Serialize PubKeyI where
    put :: PubKeyI -> Put
put = PubKeyI -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize
    get :: Get PubKeyI
get = Get PubKeyI
forall a (m :: * -> *). (Serial a, MonadGet m) => m a
deserialize

instance Binary PubKeyI where
    put :: PubKeyI -> Put
put = PubKeyI -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize
    get :: Get PubKeyI
get = Get PubKeyI
forall a (m :: * -> *). (Serial a, MonadGet m) => m a
deserialize

-- | Wrap a public key from secp256k1 library adding information about compression.
wrapPubKey :: Bool -> PubKey -> PubKeyI
wrapPubKey :: Bool -> PubKey -> PubKeyI
wrapPubKey Bool
c PubKey
p = PubKey -> Bool -> PubKeyI
PubKeyI PubKey
p Bool
c

{- | Derives a public key from a private key. This function will preserve
 compression flag.
-}
derivePubKeyI :: SecKeyI -> PubKeyI
derivePubKeyI :: SecKeyI -> PubKeyI
derivePubKeyI (SecKeyI SecKey
d Bool
c) = PubKey -> Bool -> PubKeyI
PubKeyI (SecKey -> PubKey
derivePubKey SecKey
d) Bool
c

-- | Tweak a public key.
tweakPubKey :: PubKey -> Hash256 -> Maybe PubKey
tweakPubKey :: PubKey -> Hash256 -> Maybe PubKey
tweakPubKey PubKey
p Hash256
h = PubKey -> Tweak -> Maybe PubKey
tweakAddPubKey PubKey
p (Tweak -> Maybe PubKey) -> Maybe Tweak -> Maybe PubKey
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< ByteString -> Maybe Tweak
tweak (Put -> ByteString
runPutS (Hash256 -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize Hash256
h))

{- | Elliptic curve private key type with expected public key compression
 information. Compression information is stored in private key WIF formats and
 needs to be preserved to generate the correct address from the corresponding
 public key.
-}
data SecKeyI = SecKeyI
    { SecKeyI -> SecKey
secKeyData :: !SecKey
    , SecKeyI -> Bool
secKeyCompressed :: !Bool
    }
    deriving (SecKeyI -> SecKeyI -> Bool
(SecKeyI -> SecKeyI -> Bool)
-> (SecKeyI -> SecKeyI -> Bool) -> Eq SecKeyI
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: SecKeyI -> SecKeyI -> Bool
$c/= :: SecKeyI -> SecKeyI -> Bool
== :: SecKeyI -> SecKeyI -> Bool
$c== :: SecKeyI -> SecKeyI -> Bool
Eq, Int -> SecKeyI -> ShowS
[SecKeyI] -> ShowS
SecKeyI -> String
(Int -> SecKeyI -> ShowS)
-> (SecKeyI -> String) -> ([SecKeyI] -> ShowS) -> Show SecKeyI
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [SecKeyI] -> ShowS
$cshowList :: [SecKeyI] -> ShowS
show :: SecKeyI -> String
$cshow :: SecKeyI -> String
showsPrec :: Int -> SecKeyI -> ShowS
$cshowsPrec :: Int -> SecKeyI -> ShowS
Show, ReadPrec [SecKeyI]
ReadPrec SecKeyI
Int -> ReadS SecKeyI
ReadS [SecKeyI]
(Int -> ReadS SecKeyI)
-> ReadS [SecKeyI]
-> ReadPrec SecKeyI
-> ReadPrec [SecKeyI]
-> Read SecKeyI
forall a.
(Int -> ReadS a)
-> ReadS [a] -> ReadPrec a -> ReadPrec [a] -> Read a
readListPrec :: ReadPrec [SecKeyI]
$creadListPrec :: ReadPrec [SecKeyI]
readPrec :: ReadPrec SecKeyI
$creadPrec :: ReadPrec SecKeyI
readList :: ReadS [SecKeyI]
$creadList :: ReadS [SecKeyI]
readsPrec :: Int -> ReadS SecKeyI
$creadsPrec :: Int -> ReadS SecKeyI
Read, (forall x. SecKeyI -> Rep SecKeyI x)
-> (forall x. Rep SecKeyI x -> SecKeyI) -> Generic SecKeyI
forall x. Rep SecKeyI x -> SecKeyI
forall x. SecKeyI -> Rep SecKeyI x
forall a.
(forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a
$cto :: forall x. Rep SecKeyI x -> SecKeyI
$cfrom :: forall x. SecKeyI -> Rep SecKeyI x
Generic, SecKeyI -> ()
(SecKeyI -> ()) -> NFData SecKeyI
forall a. (a -> ()) -> NFData a
rnf :: SecKeyI -> ()
$crnf :: SecKeyI -> ()
NFData)

-- | Wrap private key with corresponding public key compression flag.
wrapSecKey :: Bool -> SecKey -> SecKeyI
wrapSecKey :: Bool -> SecKey -> SecKeyI
wrapSecKey Bool
c SecKey
d = SecKey -> Bool -> SecKeyI
SecKeyI SecKey
d Bool
c

-- | Tweak a private key.
tweakSecKey :: SecKey -> Hash256 -> Maybe SecKey
tweakSecKey :: SecKey -> Hash256 -> Maybe SecKey
tweakSecKey SecKey
key Hash256
h = SecKey -> Tweak -> Maybe SecKey
tweakAddSecKey SecKey
key (Tweak -> Maybe SecKey) -> Maybe Tweak -> Maybe SecKey
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< ByteString -> Maybe Tweak
tweak (Put -> ByteString
runPutS (Hash256 -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize Hash256
h))

-- | Decode Casascius mini private keys (22 or 30 characters).
fromMiniKey :: ByteString -> Maybe SecKeyI
fromMiniKey :: ByteString -> Maybe SecKeyI
fromMiniKey ByteString
bs = do
    Bool -> Maybe ()
forall (f :: * -> *). Alternative f => Bool -> f ()
guard Bool
checkShortKey
    Bool -> SecKey -> SecKeyI
wrapSecKey Bool
False (SecKey -> SecKeyI) -> Maybe SecKey -> Maybe SecKeyI
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ByteString -> Maybe SecKey
secKey (Put -> ByteString
runPutS (Hash256 -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize (ByteString -> Hash256
forall b. ByteArrayAccess b => b -> Hash256
sha256 ByteString
bs)))
  where
    checkHash :: ByteString
checkHash = Put -> ByteString
runPutS (Put -> ByteString) -> Put -> ByteString
forall a b. (a -> b) -> a -> b
$ Hash256 -> Put
forall a (m :: * -> *). (Serial a, MonadPut m) => a -> m ()
serialize (Hash256 -> Put) -> Hash256 -> Put
forall a b. (a -> b) -> a -> b
$ ByteString -> Hash256
forall b. ByteArrayAccess b => b -> Hash256
sha256 (ByteString -> Hash256) -> ByteString -> Hash256
forall a b. (a -> b) -> a -> b
$ ByteString
bs ByteString -> ByteString -> ByteString
`BS.append` ByteString
"?"
    checkShortKey :: Bool
checkShortKey = ByteString -> Int
BS.length ByteString
bs Int -> [Int] -> Bool
forall (t :: * -> *) a. (Foldable t, Eq a) => a -> t a -> Bool
`elem` [Int
22, Int
30] Bool -> Bool -> Bool
&& ByteString -> Word8
BS.head ByteString
checkHash Word8 -> Word8 -> Bool
forall a. Eq a => a -> a -> Bool
== Word8
0x00

-- | Decode private key from WIF (wallet import format) string.
fromWif :: Network -> Base58 -> Maybe SecKeyI
fromWif :: Network -> Text -> Maybe SecKeyI
fromWif Network
net Text
wif = do
    ByteString
bs <- Text -> Maybe ByteString
decodeBase58Check Text
wif
    -- Check that this is a private key
    Bool -> Maybe ()
forall (f :: * -> *). Alternative f => Bool -> f ()
guard (ByteString -> Word8
BS.head ByteString
bs Word8 -> Word8 -> Bool
forall a. Eq a => a -> a -> Bool
== Network -> Word8
getSecretPrefix Network
net)
    case ByteString -> Int
BS.length ByteString
bs of
        -- Uncompressed format
        Int
33 -> Bool -> SecKey -> SecKeyI
wrapSecKey Bool
False (SecKey -> SecKeyI) -> Maybe SecKey -> Maybe SecKeyI
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ByteString -> Maybe SecKey
secKey (ByteString -> ByteString
BS.tail ByteString
bs)
        -- Compressed format
        Int
34 -> do
            Bool -> Maybe ()
forall (f :: * -> *). Alternative f => Bool -> f ()
guard (Bool -> Maybe ()) -> Bool -> Maybe ()
forall a b. (a -> b) -> a -> b
$ ByteString -> Word8
BS.last ByteString
bs Word8 -> Word8 -> Bool
forall a. Eq a => a -> a -> Bool
== Word8
0x01
            Bool -> SecKey -> SecKeyI
wrapSecKey Bool
True (SecKey -> SecKeyI) -> Maybe SecKey -> Maybe SecKeyI
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ByteString -> Maybe SecKey
secKey (ByteString -> ByteString
BS.tail (ByteString -> ByteString) -> ByteString -> ByteString
forall a b. (a -> b) -> a -> b
$ ByteString -> ByteString
BS.init ByteString
bs)
        -- Bad length
        Int
_ -> Maybe SecKeyI
forall a. Maybe a
Nothing

-- | Encode private key into a WIF string.
toWif :: Network -> SecKeyI -> Base58
toWif :: Network -> SecKeyI -> Text
toWif Network
net (SecKeyI SecKey
k Bool
c) =
    ByteString -> Text
encodeBase58Check (ByteString -> Text)
-> (ByteString -> ByteString) -> ByteString -> Text
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Word8 -> ByteString -> ByteString
BS.cons (Network -> Word8
getSecretPrefix Network
net) (ByteString -> Text) -> ByteString -> Text
forall a b. (a -> b) -> a -> b
$
        if Bool
c
            then SecKey -> ByteString
getSecKey SecKey
k ByteString -> Word8 -> ByteString
`BS.snoc` Word8
0x01
            else SecKey -> ByteString
getSecKey SecKey
k