{-# LANGUAGE FlexibleContexts #-}
module Main (main) where

import Control.Monad.IO.Class
import Data.Maybe (fromMaybe)
import System.Directory
import System.Environment
import System.Exit
import System.FilePath

import Futhark.Pipeline
import Futhark.Passes
import qualified Futhark.CodeGen.Backends.CSOpenCL as CSOpenCL
import Futhark.Util.Pretty (prettyText)
import Futhark.Compiler.CLI
import Futhark.Util

main :: IO ()
main = compilerMain () []
       "Compile OpenCL C#" "Generate OpenCL C# code from optimised Futhark program."
       gpuPipeline $ \() mode outpath prog -> do
          mono_libs <- liftIO $ fromMaybe "." <$> lookupEnv "MONO_PATH"

          let class_name =
                case mode of ToLibrary -> Just $ takeBaseName outpath
                             ToExecutable -> Nothing
          csprog <- either (`internalError` prettyText prog) return =<<
                    CSOpenCL.compileProg class_name prog

          let cspath = outpath `addExtension` "cs"
          liftIO $ writeFile cspath csprog

          case mode of
            ToLibrary -> return ()
            ToExecutable -> do
              ret <- liftIO $ runProgramWithExitCode "csc"
                ["-out:" ++ outpath, "-lib:"++mono_libs, "-r:Cloo.clSharp.dll,Mono.Options.dll", cspath, "/unsafe"] ""
              case ret of
                Left err ->
                  externalErrorS $ "Failed to run csc: " ++ show err
                Right (ExitFailure code, cscwarn, cscerr) ->
                  externalErrorS $ "csc failed with code " ++ show code ++ ":\n" ++ cscerr ++ cscwarn
                Right (ExitSuccess, _, _) -> liftIO $ do
                  perms <- liftIO $ getPermissions outpath
                  setPermissions outpath $ setOwnerExecutable True perms