xmonad-config/lib/Xmobar/Plugins/BacklightCommon.hs

{-# LANGUAGE OverloadedStrings #-}

--------------------------------------------------------------------------------
-- | Common backlight plugin bits
--
-- Use the custom DBus interface exported by the XMonad process so I can react
-- to signals spawned by commands

module Xmobar.Plugins.BacklightCommon (startBacklight) where

import           Data.Internal.DBus

import           RIO
import qualified RIO.Text              as T

import           Xmobar.Plugins.Common

startBacklight :: RealFrac a => ((Maybe a -> IO ()) -> SesClient -> IO ())
  -> (SesClient -> IO (Maybe a)) -> T.Text -> Callback -> IO ()
startBacklight matchSignal callGetBrightness icon cb = do
    withDBusClientConnection cb $ \c -> liftIO $ do
      matchSignal dpy c
      dpy =<< callGetBrightness c
    where
      formatBrightness b = return $ T.concat [icon, T.pack $ show (round b :: Integer), "%"]
      dpy = displayMaybe cb formatBrightness