-- SPDX-FileCopyrightText: 2021 Oxhead Alpha
-- SPDX-License-Identifier: LicenseRef-MIT-OA

-- | Parsers that are used in "Morley.Client.TezosClient.Impl"
module Morley.Client.TezosClient.Parser
  ( parseBakerFeeFromOutput
  , parseSecretKeyEncryption
  ) where

import Data.Scientific (Scientific)
import Fmt (Buildable(..))
import Text.Megaparsec (choice, customFailure)
import Text.Megaparsec qualified as P (Parsec, parse, skipManyTill)
import Text.Megaparsec.Char (newline, printChar, space)
import Text.Megaparsec.Char.Lexer (lexeme, scientific, symbol)
import Text.Megaparsec.Error (ParseErrorBundle, ShowErrorComponent(..), errorBundlePretty)

import Morley.Client.TezosClient.Types (SecretKeyEncryption(..))
import Morley.Micheline
import Morley.Michelson.Parser.Helpers (count)
import Morley.Tezos.Core
import Morley.Util.SizedList.Types
import Unsafe qualified (unsafeM)

type Parser = P.Parsec Void Text

data FeeParserException = FeeParserException (ParseErrorBundle Text Void)
  deriving stock (Eq, Show)

instance Exception FeeParserException where
  displayException (FeeParserException bundle) = errorBundlePretty bundle

instance Buildable FeeParserException where
  build = build . displayException
  -- this might seem backwards, but it's more efficient than converting to then from text
  -- which would have to happen in displayException if we define it in terms of build.

data SecretKeyEncryptionParserException =
  SecretKeyEncryptionParserException (ParseErrorBundle Text UnexpectedEncryptionType)
  deriving stock (Eq, Show)

instance Buildable SecretKeyEncryptionParserException where
  build (SecretKeyEncryptionParserException bundle) = build $ errorBundlePretty bundle

data UnexpectedEncryptionType = UnexpectedEncryptionType
  deriving stock (Eq, Ord, Show)

instance ShowErrorComponent UnexpectedEncryptionType where
  showErrorComponent UnexpectedEncryptionType =
    "Unexpected secret key encryption type occurred"

-- | Function to parse baker fee from given @octez-client@ output.
parseBakerFeeFromOutput
  :: forall n. (SingIPeano n) => Text -> Either FeeParserException (SizedList n TezosMutez)
parseBakerFeeFromOutput output = first FeeParserException $
  P.parse (count @n bakerFeeParser) "" output
  where
    bakerFeeParser :: Parser TezosMutez
    bakerFeeParser = do
      num <- P.skipManyTill (printChar <|> newline) $ do
        void $ symbol space "Fee to the baker: "
        P.skipManyTill printChar $ lexeme (newline >> pass) scientific
      Unsafe.unsafeM $ scientificToMutez num
    scientificToMutez :: Scientific -> Either Text TezosMutez
    scientificToMutez x = fmap TezosMutez $ mkMutez @Word64 $ floor $ x * 1e6

parseSecretKeyEncryption
  :: Text -> Either SecretKeyEncryptionParserException SecretKeyEncryption
parseSecretKeyEncryption output = first SecretKeyEncryptionParserException $
  P.parse secretKeyEncryptionParser "" output
  where
    secretKeyEncryptionParser :: P.Parsec UnexpectedEncryptionType Text SecretKeyEncryption
    secretKeyEncryptionParser = do
      P.skipManyTill (printChar <|> newline) $ do
        symbol space "Secret Key: " >> choice
          [ symbol space "unencrypted" >> pure UnencryptedKey
          , symbol space "encrypted" >> pure EncryptedKey
          , symbol space "ledger" >> pure LedgerKey
          , customFailure UnexpectedEncryptionType
          ]