{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE TypeFamilies #-}


module Data.CRF.Chain1.Dataset.Internal
( Ob (..)
, Lb (..)

, X (..)
, mkX
, unX
, Xs

, Y (..)
, mkY
, unY
, Ys
) where


-- import Data.Vector.Generic.Base
-- import Data.Vector.Generic.Mutable
import Data.Binary (Binary)
import Data.Ix (Ix)
import qualified Data.Vector as V
import qualified Data.Vector.Unboxed as U
import           Data.Vector.Unboxed.Deriving



-- | An observation.
newtype Ob = Ob { unOb :: Int }
    deriving ( Show, Read, Eq, Ord, Binary )
--           GeneralizedNewtypeDeriving doesn't work for this in 7.8.2:
--           , Vector U.Vector, MVector U.MVector, U.Unbox )
derivingUnbox "Ob" [t| Ob -> Int |] [| unOb |] [| Ob |]


-- | A label.
newtype Lb = Lb { unLb :: Int }
    deriving ( Show, Read, Eq, Ord, Binary, Num, Ix )
derivingUnbox "Lb" [t| Lb -> Int |] [| unLb |] [| Lb |]


-- | Simple word represented by a list of its observations.
newtype X = X { _unX :: U.Vector Ob }
    deriving (Show, Read, Eq, Ord)

-- | X constructor.
mkX :: [Ob] -> X
mkX = X . U.fromList
{-# INLINE mkX #-}

-- | X deconstructor symetric to mkX.
unX :: X -> [Ob]
unX = U.toList . _unX
{-# INLINE unX #-}

-- | Sentence of words.
type Xs = V.Vector X

-- | Probability distribution over labels. 
newtype Y = Y { _unY :: U.Vector (Lb, Double) }
    deriving (Show, Read, Eq, Ord)

-- | Y constructor.
mkY :: [(Lb, Double)] -> Y
mkY = Y . U.fromList
{-# INLINE mkY #-}

-- | Y deconstructor symetric to mkY.
unY :: Y -> [(Lb, Double)]
unY = U.toList . _unY
{-# INLINE unY #-}

-- | Sentence of Y (label choices).
type Ys = V.Vector Y