import Control.Applicative
import Control.Monad
import Control.Exception as E
import Data.Char
import Data.List
import Data.Maybe
import Data.Version
import Data.Typeable
import System.Environment
import System.FilePath hiding ((<.>))
import qualified System.FilePath as FP
import System.Directory
import System.IO.Unsafe
import Text.Printf
import GHC.Generics
import Prelude

main = do
  print =<< tryFindCabalHelperTreeLibexecDir

tryFindCabalHelperTreeLibexecDir :: IO (Maybe FilePath)
tryFindCabalHelperTreeLibexecDir = do
  exe <- getExecutablePath'
  dir <- case takeFileName exe of
    "ghc" -> do -- we're probably in ghci; try CWD
        getCurrentDirectory
    _ ->
        return $ (!!4) $ iterate takeDirectory exe

  print ("dir", dir)
  exists <- doesFileExist $ dir </> "cabal-helper.cabal"
  return $ if exists
             then Just dir
             else Nothing

getExecutablePath' :: IO FilePath
getExecutablePath' = getExecutablePath