{-# LANGUAGE FlexibleInstances #-}

module HaskellWorks.Data.Bits.AllExcess.AllExcess1 where

import Data.Word
import HaskellWorks.Data.Bits.PopCount.PopCount0
import HaskellWorks.Data.Bits.PopCount.PopCount1

import qualified Data.Bit             as Bit
import qualified Data.Bit.ThreadSafe  as BitTS
import qualified Data.Vector          as DV
import qualified Data.Vector.Storable as DVS
import qualified Data.Vector.Unboxed  as DVU

class AllExcess1 a where
  -- | Number of 1-bits minues the number of 0-bits.
  allExcess1 :: a -> Int

instance AllExcess1 [Bool] where
  allExcess1 = go 0
    where go n (True :ys) = go (n + 1) ys
          go n (False:ys) = go (n - 1) ys
          go n _          = n
  {-# INLINE allExcess1 #-}

instance AllExcess1 Word8 where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 Word16 where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 Word32 where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 Word64 where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DV.Vector Word8) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DV.Vector Word16) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DV.Vector Word32) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DV.Vector Word64) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DVS.Vector Word8) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DVS.Vector Word16) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DVS.Vector Word32) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DVS.Vector Word64) where
  allExcess1 w = fromIntegral (popCount1 w) - fromIntegral (popCount0 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DVU.Vector Bit.Bit) where
  allExcess1 w = fromIntegral (popCount0 w) - fromIntegral (popCount1 w)
  {-# INLINE allExcess1 #-}

instance AllExcess1 (DVU.Vector BitTS.Bit) where
  allExcess1 w = fromIntegral (popCount0 w) - fromIntegral (popCount1 w)
  {-# INLINE allExcess1 #-}