musicScroll-0.3.3: src/MusicScroll/MPRIS.hs

{-# LANGUAGE LambdaCase #-}

module MusicScroll.MPRIS (dbusThread) where

import Control.Exception (bracket)
import Control.Monad (forever)
import Control.Monad.Trans.State (StateT, evalStateT)
import DBus.Client
import MusicScroll.ConnState
import MusicScroll.DBusSignals
import MusicScroll.LyricsPipeline
import MusicScroll.TrackInfo
import Pipes as P
import Pipes.Concurrent

dbusThread :: Output TrackIdentifier -> Output ErrorCause -> IO a
dbusThread trackout errorout =
  bracket
    connectSession
    disconnect
    (evalStateT loop . newConnState)
  where
    loop :: StateT ConnState IO a
    loop =
      forever $
        tryGetInfo >>= \case
          Left (NoMusicClient _) -> changeMusicClient
          Left NoSong ->
            do
              runEffect $ yield ENoSong >-> toOutput errorout
              waitForChange mediaPropChangeRule
          Right trackIdent ->
            do
              runEffect $ yield trackIdent >-> toOutput trackout
              waitForChange mediaPropChangeRule