{-# LANGUAGE DuplicateRecordFields, OverloadedLists #-}
{-# OPTIONS_GHC -Wall #-}
module Rubyhs (main) where

import Control.Monad.Fail (MonadFail)
import Data.Aeson (eitherDecode, encode)
import Data.ByteString.Lazy (ByteString)
import Data.Foldable (traverse_)
import Data.Language.Ruby (Block)
import Frelude
import System.Environment (getArgs)
import System.Process (readProcess)
import qualified Data.ByteString.Lazy.Char8 as ByteString
import Rubyhs.References (references)

main :: IO ()
main = getArgs >>= traverse_ run

run :: FilePath -> IO ()
run p = do
  json <- runParser p
  block <- decodeFail @_ @Block $ ByteString.pack json
  ByteString.putStrLn $ encode $ references block

decodeFail :: MonadFail m => FromJSON a => ByteString -> m a
decodeFail s = case eitherDecode s of
  Left err -> Frelude.fail err
  Right a -> pure a

runParser :: FilePath -> IO String
runParser p = sh "ruby-parse" ["--emit-json", "--25", p]

sh :: String -> [String] -> IO String
sh cmd args = readProcess cmd args mempty