{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE TypeFamilies      #-}

module HaskellWorks.Data.Bits.ElemFixedBitSize
    ( ElemFixedBitSize(..)
    ) where

import Data.Word
import HaskellWorks.Data.Positioning

import qualified Data.Vector          as DV
import qualified Data.Vector.Storable as DVS

-- | Class of values that have elements of a fixed bit size
--
-- >>> elemFixedBitSize (Vector Word8)
-- 8
class ElemFixedBitSize v where
  -- | The element type of the elemnet
  type Elem v
  -- | Get the bit size of an element for a given composite bit-string type.
  --
  -- >>> elemFixedBitSize (Vector Word8)
  -- 8
  elemFixedBitSize :: v -> Count

instance ElemFixedBitSize [Bool] where
  type Elem [Bool] = Bool
  elemFixedBitSize _ = 1

instance ElemFixedBitSize [Word8] where
  type Elem [Word8] = Word8
  elemFixedBitSize _ = 8

instance ElemFixedBitSize [Word16] where
  type Elem [Word16] = Word16
  elemFixedBitSize _ = 16

instance ElemFixedBitSize [Word32] where
  type Elem [Word32] = Word32
  elemFixedBitSize _ = 32

instance ElemFixedBitSize [Word64] where
  type Elem [Word64] = Word64
  elemFixedBitSize _ = 64

instance ElemFixedBitSize (DV.Vector Bool) where
  type Elem (DV.Vector Bool) = Bool
  elemFixedBitSize _ = 1

instance ElemFixedBitSize (DV.Vector Word8) where
  type Elem (DV.Vector Word8) = Word8
  elemFixedBitSize _ = 8

instance ElemFixedBitSize (DV.Vector Word16) where
  type Elem (DV.Vector Word16) = Word16
  elemFixedBitSize _ = 16

instance ElemFixedBitSize (DV.Vector Word32) where
  type Elem (DV.Vector Word32) = Word32
  elemFixedBitSize _ = 32

instance ElemFixedBitSize (DV.Vector Word64) where
  type Elem (DV.Vector Word64) = Word64
  elemFixedBitSize _ = 64

instance ElemFixedBitSize (DVS.Vector Bool) where
  type Elem (DVS.Vector Bool) = Bool
  elemFixedBitSize _ = 1

instance ElemFixedBitSize (DVS.Vector Word8) where
  type Elem (DVS.Vector Word8) = Word8
  elemFixedBitSize _ = 8

instance ElemFixedBitSize (DVS.Vector Word16) where
  type Elem (DVS.Vector Word16) = Word16
  elemFixedBitSize _ = 16

instance ElemFixedBitSize (DVS.Vector Word32) where
  type Elem (DVS.Vector Word32) = Word32
  elemFixedBitSize _ = 32

instance ElemFixedBitSize (DVS.Vector Word64) where
  type Elem (DVS.Vector Word64) = Word64
  elemFixedBitSize _ = 64