{-# LANGUAGE GADTs              #-}
{-# LANGUAGE FlexibleContexts   #-}
{-# LANGUAGE ImpredicativeTypes #-}
{-# LANGUAGE TypeOperators      #-}

module Thermoprint.Server.QMConfig
       ( QMConfig(..)
       ) where

import Control.Monad.Trans.Resource
import Control.Monad.Trans.Control
import Control.Monad.Trans.Identity
import Control.Monad.Logger
import Control.Monad.Reader
import Control.Monad.IO.Class
import Control.Monad.Morph
import Control.Category
import Prelude hiding (id, (.))
import Servant.Server.Internal.Enter (enter, (:~>)(..))

import Data.Default.Class

import Control.Concurrent.STM

import Thermoprint.Server.Queue

data QMConfig m where
  QMConfig :: ( MonadTrans t
              , MFunctor t
              , Monad (t STM)
              , MonadIO (t IO)
              ) => QueueManager t -> (t IO) :~> m -> QMConfig m
  QMConfig' :: ( MonadIO m
               ) => ( forall t. ( MonadTrans t
                                , MFunctor t
                                , Monad (t STM)
                                , MonadIO (t IO)
                                ) => QueueManager t
                    ) -> QMConfig m

instance MonadIO m => Default (QMConfig m) where
  def = QMConfig idQM $ Nat (liftIO . runIdentityT)