Instances.hs

{-# LANGUAGE FlexibleContexts, FlexibleInstances, GeneralizedNewtypeDeriving, MultiParamTypeClasses,
             PackageImports, TypeSynonymInstances, UndecidableInstances #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
-- |AptIO is an instance of the RWS monad used to manage the global
-- state and output style parameters of clients of the Apt library,
-- such as the autobuilder.
module Apt.Instances
    ( 
    ) where

import "MonadCatchIO-mtl" Control.Monad.CatchIO (MonadCatchIO)
import Control.Monad.Reader (ReaderT)
import Control.Monad.State (get, MonadIO, MonadTrans(lift), put)
import Apt.AptIOT (AptIOT)
import Apt.AptState (repoMap)
import Apt.MonadApt (MonadApt(getApt, putApt))
import Debian.Repo.Types.Repository (MonadRepoCache(..))
import System.Posix.Files (deviceID, fileID, FileStatus, modificationTime)

instance Ord FileStatus where
    compare a b = compare (deviceID a, fileID a, modificationTime a) (deviceID b, fileID b, modificationTime b)

instance Eq FileStatus where
    a == b = compare a b == EQ

instance (MonadIO m, Functor m, MonadCatchIO m) => MonadApt (AptIOT m) where
    getApt = get
    putApt = put

instance MonadApt m => MonadApt (ReaderT s m) where
    getApt = lift getApt
    putApt = lift . putApt

instance MonadApt m => MonadRepoCache m where
    getRepoCache = getApt >>= return . repoMap
    putRepoCache m = getApt >>= \ a -> putApt (a {repoMap = m})