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

import System.Win32.DLL
import System.Win32.Types as Win32Types
import Foreign.Ptr
import Foreign.C.String
import Foreign.ForeignPtr

foreign import ccall "dynamic"
  --c_TestInt :: FunPtr (Int -> IO (Int)) -> Int -> IO (Int)
  c_funcRetString :: FunPtr (IO (CString)) -> IO (CString)
foreign import ccall "dynamic"
  c_funcInstantiate :: FunPtr (CString -> CString -> HMODULE -> IO (Ptr ())) ->  CString -> CString -> HMODULE -> IO (Ptr ())

dllNames = ["tank"]

invokeFunction dll funcName funcType convType = do
  func <- getProcAddress dll funcName
  ret <- funcType $ castPtrToFunPtr func
  convType ret

main :: IO ()

main = do
  dll <- loadLibrary $ head dllNames
  invokeFunction dll "fmi2GetVersion" c_funcRetString peekCString >>= putStrLn . show
  invokeFunction dll "fmi2GetTypesPlatform" c_funcRetString peekCString >>= putStrLn . show
  instantiateFunc <- getProcAddress dll "fmi2Instantiate"
  t1 <- withCString "t1"
  t2 <- withCString "t2"
  instantiateRet <- c_funcInstantiate (castPtrToFunPtr instantiateFunc) t1 t2 dll
  putStrLn . show $ 1


C:\source\speciale\r_and_d\source\hs_prototype\dynamic_loading_tank_tankcontroller\main.hs:29:9-24: Couldn't match expected type `IO CString' …
                with actual type `(CString -> IO a0) -> IO a0'
    Probable cause: `withCString' is applied to too few arguments
    In a stmt of a 'do' block: t1 <- withCString "t1"
    In the expression:
      do { dll <- loadLibrary $ head dllNames;
           invokeFunction dll "fmi2GetVersion" c_funcRetString peekCString
           >>= putStrLn . show;
           invokeFunction
             dll "fmi2GetTypesPlatform" c_funcRetString peekCString
           >>= putStrLn . show;
           instantiateFunc <- getProcAddress dll "fmi2Instantiate";
           .... }
C:\source\speciale\r_and_d\source\hs_prototype\dynamic_loading_tank_tankcontroller\main.hs:30:9-24: Couldn't match expected type `IO CString' …
                with actual type `(CString -> IO a1) -> IO a1'
    Probable cause: `withCString' is applied to too few arguments
    In a stmt of a 'do' block: t2 <- withCString "t2"
    In the expression:
      do { dll <- loadLibrary $ head dllNames;
           invokeFunction dll "fmi2GetVersion" c_funcRetString peekCString
           >>= putStrLn . show;
           invokeFunction
             dll "fmi2GetTypesPlatform" c_funcRetString peekCString
           >>= putStrLn . show;
           instantiateFunc <- getProcAddress dll "fmi2Instantiate";
           .... }
Compilation failed