-- Copyright 2023 Lennart Augustsson
-- See LICENSE file for full license.
{-# OPTIONS_GHC -Wno-orphans #-}
{-# LANGUAGE DataKinds #-}
-- Functions for GHC that are defined in the UHS libs.
module Compat(module Compat, Type) where
import Data.Maybe
import Data.Text(Text, append, pack)
import Control.Exception
import GHC.Types
import System.Environment
import System.IO

------- List --------

takeWhileEnd :: forall a . (a -> Bool) -> [a] -> [a]
takeWhileEnd p = reverse . takeWhile p . reverse

------- IO --------

openFileM :: FilePath -> IOMode -> IO (Maybe Handle)
openFileM path m = do
  r <- (try $ openFile path m) :: IO (Either IOError Handle)
  case r of
    Left _ -> return Nothing
    Right h -> return (Just h)

openTmpFile :: String -> IO (String, Handle)
openTmpFile tmplt = do
  mtmp <- lookupEnv "TMPDIR"
  let tmp = fromMaybe "/tmp" mtmp
  res <- try $ openTempFile tmp tmplt
  case res of
    Right x -> return x
    Left (_::SomeException) -> openTempFile "." tmplt

------- Read --------

usingMhs :: Bool
usingMhs = False

_wordSize :: Int
_wordSize = 64

_isWindows :: Bool
_isWindows = False

-- This cannot be implemented with GHC.
rnfNoErr :: forall a . a -> ()
rnfNoErr _ = ()

-- This cannot be implemented with GHC.
rnfErr :: forall a . a -> ()
rnfErr _ = ()

appendDot :: Text -> Text -> Text
appendDot x y = x `append` pack "." `append` y