{-# LANGUAGE ForeignFunctionInterface, TypeFamilies, MultiParamTypeClasses, 
             FlexibleInstances, TypeSynonymInstances, 
             EmptyDataDecls, ExistentialQuantification, ScopedTypeVariables #-}

-- module HROOT.Class.Interface where

module HROOT.Core.TSystem.Interface where


import Data.Word
import Foreign.C
import Foreign.Ptr
import Foreign.ForeignPtr
import FFICXX.Runtime.Cast

import HROOT.Core.TSystem.RawType

import HROOT.Core.TNamed.Interface
---- ============ ----



class (ITNamed a) => ITSystem a where

    processEvents :: a -> IO CInt 

instance Existable TSystem where
  data Exist TSystem = forall a. (FPtr a, ITSystem a) => ETSystem a

upcastTSystem :: (FPtr a, ITSystem a) => a -> TSystem
upcastTSystem h = let fh = get_fptr h
                      fh2 :: ForeignPtr RawTSystem = castForeignPtr fh
                  in cast_fptr_to_obj fh2

downcastTSystem :: (FPtr a, ITSystem a) => TSystem -> a 
downcastTSystem h = let fh = get_fptr h
                        fh2 = castForeignPtr fh
                    in cast_fptr_to_obj fh2