-- | Implementation of user-visible IO. Maybe not a good name for this.

module ZMachine.IO where

import ZMachine.IO.Base
import ZMachine.Base

import Control.Monad.State (liftIO, gets)
import Control.Concurrent.MVar

_zio :: IOOperation -> ZM ()
_zio op = do f <- gets zs_io_
             liftIO $ f op

_zioWithMVar :: (MVar a -> IOOperation) -> ZM a
_zioWithMVar opf = do mvar <- liftIO $ newEmptyMVar
                      _zio $ opf mvar
                      liftIO $ takeMVar mvar


zioRead :: ZM String
zioRead = _zioWithMVar IORead

zioReadChar :: ZM Char
zioReadChar = _zioWithMVar IOReadChar

zioWrite :: String -> ZM ()
zioWrite s = _zio $ IOWrite s

zioEraseWindow :: Val -> ZM ()
zioEraseWindow win = _zio $ IOEraseWindow win

zioSetWindow :: Val -> ZM ()
zioSetWindow win = _zio $ IOSetWindow win

zioSplitWindow :: Val -> ZM ()
zioSplitWindow split = _zio $ IOSplitWindow split

zioSetCursor :: Val -> Val -> ZM ()
zioSetCursor x y = _zio $ IOSetCursor x y