import Distribution.Simple
import Distribution.Simple.InstallDirs
import Distribution.Simple.LocalBuildInfo
import Distribution.PackageDescription

import System

system' cmd = do 
    exit <- system cmd
    case exit of
      ExitSuccess -> return ()
      ExitFailure _ -> exitWith exit

buildLib args flags desc local 
    = system' "make -C sdl"

findSDL args flags
    = do system' "make -C src SDLflags.hs"
         return emptyHookedBuildInfo

-- This is a hack. I don't know how to tell cabal that a data file needs
-- installing but shouldn't be in the distribution. And it won't make the
-- distribution if it's not there, so instead I just delete
-- the file after configure.

postConfLib args flags desc local
    = system' "make -C sdl clean"

addPrefix pfx var c = "export " ++ var ++ "=" ++ show pfx ++ "/" ++ c ++ ":$" ++ var

postInstLib args flags desc local
    = do let pfx = prefix (installDirTemplates local)
         system' $ "make -C sdl install PREFIX=" ++ show pfx

main = defaultMainWithHooks (simpleUserHooks { preBuild = findSDL,
                                               postBuild = buildLib,
                                               postConf = postConfLib,
                                               postInst = postInstLib })