module Types where

import Control.Monad
import DynFlags
import Exception
import GHC
import GHC.Paths (libdir)

----------------------------------------------------------------

data Options = Options {
    convert   :: [String] -> String
  , hlintOpts :: [String]
  , operators :: Bool
  }

withGHC :: (MonadPlus m) => Ghc (m a) -> IO (m a)
withGHC body = ghandle ignore $ runGhc (Just libdir) body
  where
    ignore :: (MonadPlus m) => SomeException -> IO (m a)
    ignore _ = return mzero

----------------------------------------------------------------

initSession0 :: Ghc [PackageId]
initSession0 = getSessionDynFlags >>= setSessionDynFlags

initSession :: [String] -> Maybe [FilePath] -> Ghc [PackageId]
initSession cmdOpts midirs = do
    dflags <- getSessionDynFlags
    let opts = map noLoc cmdOpts
    (dflags',_,_) <- parseDynamicFlags dflags opts
    setSessionDynFlags $ setFlags dflags' midirs

----------------------------------------------------------------

setFlags :: DynFlags -> Maybe [FilePath] -> DynFlags
setFlags d midirs = maybe d' (\x -> d' { importPaths = x }) midirs
  where
    d' = d {
        packageFlags = ghcPackage : packageFlags d
      , ghcLink = NoLink
      , hscTarget = HscInterpreted
      }

ghcPackage :: PackageFlag
ghcPackage = ExposePackage "ghc"

----------------------------------------------------------------

setTargetFile :: (GhcMonad m) => String -> m ()
setTargetFile file = do
    target <- guessTarget file Nothing
    setTargets [target]