module SDL.TTF.Internals where

import Foreign.C.String
import Foreign.C.Types (CInt)
import Foreign.Marshal.Alloc
import Foreign.Storable
import Foreign.Ptr
import Control.Monad
import Control.Monad.IO.Class

import qualified SDL as SDL
import qualified SDL.Raw as Raw

import qualified SDL.TTF.FFI as FFI

peekInts
  :: MonadIO m
  => (FFI.TTFFont -> CString -> Ptr CInt -> Ptr CInt -> IO CInt)
  -> FFI.TTFFont
  -> String
  -> m (Int,Int)
peekInts fn fontPtr text = liftIO $ do
    alloca $ \wPtr ->
      alloca $ \hPtr -> do
        -- TODO: handle errors
        void $ withCString text $ \cstr -> fn fontPtr cstr wPtr hPtr
        w <- peek wPtr
        h <- peek hPtr
        return (fromIntegral w, fromIntegral h)

-- | Straight from the code of "sdl2" package, which is not exported. It will make a high level Surface from a Raw Surface. I will move this to somewhere safe, soon
unmanagedSurface :: Ptr Raw.Surface -> SDL.Surface
unmanagedSurface s = SDL.Surface s Nothing