{-# OPTIONS_GHC -fno-warn-orphans #-}
module TestUtils (
    run
  , runD
  , runD'
  , runE
  , runNullLog
  , shouldReturnError
  , isPkgDbAt
  , isPkgConfDAt
  , module Language.Haskell.GhcMod.Monad
  , module Language.Haskell.GhcMod.Types
  ) where

import Language.Haskell.GhcMod.Logging
import Language.Haskell.GhcMod.Monad
import Language.Haskell.GhcMod.Cradle
import Language.Haskell.GhcMod.Types

import Control.Arrow
import Control.Applicative
import Control.Monad.Error (ErrorT, runErrorT)
import Control.Monad.Trans.Journal
import Data.List.Split
import Data.String
import System.FilePath
import System.Directory
import Test.Hspec

import Exception

testLogLevel :: GmLogLevel
testLogLevel = GmDebug

extract :: Show e => IO (Either e a, w) -> IO a
extract action = do
  (r,_) <- action
  case r of
    Right a ->  return a
    Left e -> error $ show e

withSpecCradle :: IOish m => FilePath -> (Cradle -> m a) -> m a
withSpecCradle cradledir f =
    gbracket (liftIO $ findSpecCradle cradledir) (liftIO . cleanupCradle) f

withGhcModEnvSpec :: IOish m => FilePath -> Options -> (GhcModEnv -> m a) -> m a
withGhcModEnvSpec dir opt f = withSpecCradle dir $ withGhcModEnv' opt f

runGhcModTSpec :: Options -> GhcModT IO a -> IO (Either GhcModError a, GhcModLog)
runGhcModTSpec opt action = do
  dir <- getCurrentDirectory
  runGhcModTSpec' dir opt action

runGhcModTSpec' :: IOish m
    => FilePath -> Options -> GhcModT m b -> m (Either GhcModError b, GhcModLog)
runGhcModTSpec' dir opt action = liftIO (canonicalizePath dir) >>= \dir' ->
    withGhcModEnvSpec dir' opt $ \env -> do
      first (fst <$>) <$> runGhcModT'' env defaultGhcModState
        (gmSetLogLevel (logLevel opt) >> action)

-- | Run GhcMod
run :: Options -> GhcModT IO a -> IO a
run opt a = extract $ runGhcModTSpec opt a

-- | Run GhcMod with default options
runD :: GhcModT IO a -> IO a
runD =
    extract . runGhcModTSpec defaultOptions { logLevel = testLogLevel }

runD' :: FilePath -> GhcModT IO a -> IO a
runD' dir =
    extract . runGhcModTSpec' dir defaultOptions { logLevel = testLogLevel }

runE :: ErrorT e IO a -> IO (Either e a)
runE = runErrorT

runNullLog :: MonadIO m => JournalT GhcModLog m a -> m a
runNullLog action = do
  (a,w) <- runJournalT action
  liftIO $ print w
  return a

shouldReturnError :: Show a
                  => IO (Either GhcModError a, GhcModLog)
                  -> Expectation
shouldReturnError action = do
  (a,_) <- action
  a `shouldSatisfy` isLeft
 where
   isLeft (Left _) = True
   isLeft _ = False

isPkgConfD :: FilePath -> Bool
isPkgConfD d = let
    (_dir, pkgconfd) = splitFileName d
    in case splitOn "-" pkgconfd of
         [_arch, _platform, _compiler, _compver, "packages.conf.d"] -> True
         _ -> False

isPkgConfDAt :: FilePath -> FilePath -> Bool
isPkgConfDAt d d' | d == takeDirectory d' && isPkgConfD d' = True
isPkgConfDAt _ _ = False

isPkgDbAt :: FilePath -> GhcPkgDb -> Bool
isPkgDbAt d (PackageDb dir) = isPkgConfDAt d dir
isPkgDbAt _ _ = False

instance IsString ModuleName where
    fromString = mkModuleName