-- | Indicate that something is `Cached`.
module NewtypeZoo.Cached
  ( Cached(Cached)
  , _theCached
  , theCached
  ) where

import           Control.Comonad (Comonad)
import           Control.DeepSeq (NFData)
import           Control.Monad.Fix (MonadFix)
import           Control.Monad.Zip (MonadZip)
import           Data.Bits       (Bits,FiniteBits)
import           Data.Copointed  (Copointed)
import           Data.Default    (Default)
import           Data.Functor.Classes (Eq1, Ord1, Read1, Show1)
import           Data.Functor.Identity
import           Data.Ix         (Ix)
import           Data.Profunctor (Profunctor, dimap)
import           Data.Pointed    (Pointed)
import           Data.String     (IsString)
import           Data.Typeable   (Typeable)
import           Foreign.Storable (Storable)
import           GHC.Generics    (Generic, Generic1)
import           System.Random   (Random)
import           Test.QuickCheck (Arbitrary)

newtype Cached a = Cached a
  deriving ( Eq
           , Ord
           , Read
           , Show
           , NFData
           , Foldable
           , Traversable
           , Functor
           , Default
           , Monoid
           , Semigroup
           , Typeable
           , Generic
           , Generic1
           , Random
           , Arbitrary
           , Bounded
           , Enum
           , Floating
           , Fractional
           , Integral
           , Num
           , Real
           , RealFloat
           , RealFrac
           , Ix
           , IsString
           , Bits
           , FiniteBits
           )
  deriving ( Eq1
           , Ord1
           , Read1
           , Show1
           , Pointed
           , Copointed
           , Applicative
           , MonadFix
           , Monad
           , MonadZip
           , Comonad
           )
           via Identity

_theCached :: Cached x -> x
_theCached (Cached !x) = x
{-# INLINE _theCached #-}

theCached :: forall a b p f. (Profunctor p, Functor f) => p a (f b) -> p (Cached a) (f (Cached b))
theCached = dimap _theCached (fmap Cached)
{-# INLINE theCached #-}