{-# LANGUAGE CPP, FlexibleContexts #-}

module Graphics.UI.FLTK.LowLevel.X (flcOpenDisplay, flcXid) where
import Graphics.UI.FLTK.LowLevel.Fl_Types
import Graphics.UI.FLTK.LowLevel.Hierarchy
import Graphics.UI.FLTK.LowLevel.Dispatch
import Foreign.Ptr
#include "Fl_C.h"
#include "xC.h"

{# fun flc_open_display as flcOpenDisplay {} -> `()' #}

{# fun flc_xid as flcXid' {`Ptr ()'} -> `Ptr ()' #}
flcXid :: (Parent a Window) => Ref a -> IO (Maybe WindowHandle)
flcXid win =
  withRef
    win
    (
      \winPtr -> do
         res <- flcXid' winPtr
         if (res == nullPtr)
         then return Nothing
         else return (Just (WindowHandle res))
    )