{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE CPP #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE UndecidableInstances #-}
-- |
-- Module      : Data.Massiv.Array.Manifest.Unboxed
-- Copyright   : (c) Alexey Kuleshevich 2018-2022
-- License     : BSD3
-- Maintainer  : Alexey Kuleshevich <lehins@yandex.ru>
-- Stability   : experimental
-- Portability : non-portable
--
module Data.Massiv.Array.Manifest.Unboxed
  ( U (..)
  , Unbox
  , Array(..)
  , MArray(..)
  , toUnboxedVector
  , toUnboxedMVector
  , fromUnboxedVector
  , fromUnboxedMVector
  ) where

import Control.DeepSeq (NFData(..), deepseq)
import Control.Monad.Primitive (stToPrim)
import Data.Massiv.Array.Delayed.Pull (D, compareArrays, eqArrays)
import Data.Massiv.Array.Manifest.Internal
import Data.Massiv.Array.Manifest.List as A
import Data.Massiv.Array.Mutable
import Data.Massiv.Core.Common
import Data.Massiv.Core.List
import Data.Massiv.Core.Operations
import Data.Massiv.Vector.Stream as S (isteps, steps)
import qualified Data.Vector.Generic.Mutable as VGM
import Data.Vector.Unboxed (Unbox)
import qualified Data.Vector.Unboxed as VU
import qualified Data.Vector.Unboxed.Mutable as MVU
import GHC.Exts as GHC (IsList(..))
import Prelude hiding (mapM)
import System.IO.Unsafe (unsafePerformIO)

#include "massiv.h"

-- | Representation for `Unbox`ed elements
data U = U deriving Show

data instance Array U ix e = UArray { uComp :: !Comp
                                    , uSize :: !(Sz ix)
                                    , uData :: !(VU.Vector e)
                                    }
data instance MArray s U ix e = MUArray !(Sz ix) !(VU.MVector s e)

instance (Ragged L ix e, Show e, Unbox e) => Show (Array U ix e) where
  showsPrec = showsArrayPrec id
  showList = showArrayList

instance NFData ix => NFData (Array U ix e) where
  rnf (UArray c sz v) = c `deepseq` sz `deepseq` v `deepseq` ()
  {-# INLINE rnf #-}

instance NFData ix => NFData (MArray s U ix e) where
  rnf (MUArray sz mv) = sz `deepseq` mv `deepseq` ()
  {-# INLINE rnf #-}

instance Strategy U where
  getComp = uComp
  {-# INLINE getComp #-}
  setComp c arr = arr { uComp = c }
  {-# INLINE setComp #-}
  repr = U


instance (Unbox e, Eq e, Index ix) => Eq (Array U ix e) where
  (==) = eqArrays (==)
  {-# INLINE (==) #-}

instance (Unbox e, Ord e, Index ix) => Ord (Array U ix e) where
  compare = compareArrays compare
  {-# INLINE compare #-}


instance Unbox e => Source U e where
  unsafeLinearIndex (UArray _ _ v) =
    INDEX_CHECK("(Source U ix e).unsafeLinearIndex", Sz . VU.length, VU.unsafeIndex) v
  {-# INLINE unsafeLinearIndex #-}

  unsafeOuterSlice (UArray c _ v) szL i =
    let k = totalElem szL
    in UArray c szL $ VU.unsafeSlice (i * k) k v
  {-# INLINE unsafeOuterSlice #-}

  unsafeLinearSlice i k (UArray c _ v) = UArray c k $ VU.unsafeSlice i (unSz k) v
  {-# INLINE unsafeLinearSlice #-}

instance Index ix => Shape U ix where
  maxLinearSize = Just . SafeSz . elemsCount
  {-# INLINE maxLinearSize #-}

instance Size U where
  size = uSize
  {-# INLINE size #-}
  unsafeResize !sz !arr = arr { uSize = sz }
  {-# INLINE unsafeResize #-}

instance (Unbox e, Index ix) => Load U ix e where
  makeArray comp sz f = compute (makeArray comp sz f :: Array D ix e)
  {-# INLINE makeArray #-}

  makeArrayLinear !comp !sz f = unsafePerformIO $ generateArrayLinear comp sz (pure . f)
  {-# INLINE makeArrayLinear #-}

  replicate comp !sz !e = runST (newMArray sz e >>= unsafeFreeze comp)
  {-# INLINE replicate #-}

  iterArrayLinearST_ !scheduler !arr =
    splitLinearlyWith_ scheduler (elemsCount arr) (unsafeLinearIndex arr)
  {-# INLINE iterArrayLinearST_ #-}

instance (Unbox e, Index ix) => StrideLoad U ix e





instance Unbox e => Manifest U e where

  unsafeLinearIndexM (UArray _ _ v) =
    INDEX_CHECK("(Manifest U ix e).unsafeLinearIndexM", Sz . VU.length, VU.unsafeIndex) v
  {-# INLINE unsafeLinearIndexM #-}

  sizeOfMArray (MUArray sz _) = sz
  {-# INLINE sizeOfMArray #-}

  unsafeResizeMArray sz (MUArray _ mv) = MUArray sz mv
  {-# INLINE unsafeResizeMArray #-}

  unsafeLinearSliceMArray i k (MUArray _ mv) = MUArray k $ MVU.unsafeSlice i (unSz k) mv
  {-# INLINE unsafeLinearSliceMArray #-}

  unsafeThaw (UArray _ sz v) = MUArray sz <$> VU.unsafeThaw v
  {-# INLINE unsafeThaw #-}

  unsafeFreeze comp (MUArray sz v) = UArray comp sz <$> VU.unsafeFreeze v
  {-# INLINE unsafeFreeze #-}

  unsafeNew sz = MUArray sz <$> MVU.unsafeNew (totalElem sz)
  {-# INLINE unsafeNew #-}

  initialize (MUArray _ marr) = stToPrim (VGM.basicInitialize marr)
  {-# INLINE initialize #-}

  unsafeLinearCopy (MUArray _ mvFrom) iFrom (MUArray _ mvTo) iTo (Sz k) =
    MVU.unsafeCopy (MVU.unsafeSlice iTo k mvTo) (MVU.unsafeSlice iFrom k mvFrom)
  {-# INLINE unsafeLinearCopy #-}

  unsafeLinearRead (MUArray _ mv) =
    INDEX_CHECK("(Manifest U ix e).unsafeLinearRead", Sz . MVU.length, MVU.unsafeRead) mv
  {-# INLINE unsafeLinearRead #-}

  unsafeLinearWrite (MUArray _ mv) =
    INDEX_CHECK("(Manifest U ix e).unsafeLinearWrite", Sz . MVU.length, MVU.unsafeWrite) mv
  {-# INLINE unsafeLinearWrite #-}

  unsafeLinearGrow (MUArray _ mv) sz = MUArray sz <$> MVU.unsafeGrow mv (totalElem sz)
  {-# INLINE unsafeLinearGrow #-}


instance (Index ix, Unbox e) => Stream U ix e where
  toStream = S.steps
  {-# INLINE toStream #-}
  toStreamIx = S.isteps
  {-# INLINE toStreamIx #-}


instance (Unbox e, IsList (Array L ix e), Ragged L ix e) => IsList (Array U ix e) where
  type Item (Array U ix e) = Item (Array L ix e)
  fromList = A.fromLists' Seq
  {-# INLINE fromList #-}
  toList = GHC.toList . toListArray
  {-# INLINE toList #-}


instance (VU.Unbox e, Num e) => FoldNumeric U e where
  unsafeDotProduct = defaultUnsafeDotProduct
  {-# INLINE unsafeDotProduct #-}
  powerSumArray = defaultPowerSumArray
  {-# INLINE powerSumArray #-}
  foldArray = defaultFoldArray
  {-# INLINE foldArray #-}

instance (VU.Unbox e, Num e) => Numeric U e where
  unsafeLiftArray = defaultUnsafeLiftArray
  {-# INLINE unsafeLiftArray #-}
  unsafeLiftArray2 = defaultUnsafeLiftArray2
  {-# INLINE unsafeLiftArray2 #-}


-- | /O(1)/ - Unwrap unboxed array and pull out the underlying unboxed vector.
--
-- @since 0.2.1
toUnboxedVector :: Array U ix e -> VU.Vector e
toUnboxedVector = uData
{-# INLINE toUnboxedVector #-}


-- | /O(1)/ - Unwrap unboxed mutable array and pull out the underlying unboxed mutable vector.
--
-- @since 0.2.1
toUnboxedMVector :: MArray s U ix e -> VU.MVector s e
toUnboxedMVector (MUArray _ mv) = mv
{-# INLINE toUnboxedMVector #-}



-- | /O(1)/ - Wrap an unboxed vector and produce an unboxed flat array.
--
-- @since 0.6.0
fromUnboxedVector :: VU.Unbox e => Comp -> VU.Vector e -> Vector U e
fromUnboxedVector comp v = UArray comp (SafeSz (VU.length v)) v
{-# INLINE fromUnboxedVector #-}


-- | /O(1)/ - Wrap an unboxed mutable vector and produce a mutable unboxed flat array.
--
-- @since 0.5.0
fromUnboxedMVector :: Unbox e => VU.MVector s e -> MVector s U e
fromUnboxedMVector mv = MUArray (SafeSz (MVU.length mv)) mv
{-# INLINE fromUnboxedMVector #-}