import Distribution.Helper
import System.Environment.Extra (lookupEnv)
import System.Posix.Env (setEnv)
import System.Process
import System.Exit
import Data.Maybe
import Data.Either
import Data.Version
import Data.Functor
import Control.Exception
import Control.Arrow

import CabalHelper.Common
import CabalHelper.Compile
import CabalHelper.Types

main :: IO ()
main = do
  flip (setEnv "HOME") True =<< fromMaybe "/tmp" <$> lookupEnv "TMPDIR"
  writeAutogenFiles readProcess "." "./dist"

  _ <- system "cabal update"

  let vers :: [(Version, [Version])]
      vers = map (parseVer *** map parseVer) [
               ("7.4", [ "1.14.0"
                       ]),

               ("7.6", [ "1.16.0"
                       , "1.16.0.1"
                       , "1.16.0.2"
                       , "1.16.0.3"
                       ]),

               ("7.8", [
--                         "1.18.0"
--                       , "1.18.1"
                         "1.18.1.1"
--                       , "1.18.1.2"
                       , "1.18.1.3"
                       , "1.18.1.4"
                       , "1.18.1.5"
                       , "1.18.1.6"

                       , "1.20.0.0"
                       , "1.20.0.1"
                       , "1.20.0.2"
                       , "1.20.0.3"
                       , "1.22.0.0"
                       , "1.22.1.0"
                       , "1.22.1.1"
                       ]),

               ("7.10", [
                         "1.22.2.0"
                       , "1.22.3.0"
                       , "1.22.4.0"
                       ])
             ]

  ghcVer <- ghcVersion defaultOptions

  let cabalVers = concat $ map snd $ dropWhile ((<ghcVer) . fst)  vers

  rvs <- mapM compilePrivatePkgDb cabalVers

  if any isLeft' rvs
     then exitFailure
     else exitSuccess
 where
   isLeft' (Left _) = True
   isLeft' (Right _) = False

compilePrivatePkgDb :: Version -> IO (Either ExitCode FilePath)
compilePrivatePkgDb cabalVer = do
    db <- installCabal defaultOptions cabalVer `catch`
          \(SomeException _) -> errorInstallCabal cabalVer "dist"
    compileWithPkg "." (Just db) cabalVer

compileWithPkg :: FilePath -> Maybe FilePath -> Version -> IO (Either ExitCode FilePath)
compileWithPkg chdir mdb ver =
    compile "dist" defaultOptions $ Compile chdir Nothing mdb ver [cabalPkgId ver]

cabalPkgId :: Version -> String
cabalPkgId v = "Cabal-" ++ showVersion v