{-# LANGUAGE BangPatterns        #-}
{-# LANGUAGE ScopedTypeVariables #-}

module HaskellWorks.Data.RankSelect.ValidateSpec (spec) where

import Control.Monad
import Control.Monad.IO.Class
import Data.List                                 (isSuffixOf)
import Data.Monoid                               ((<>))
import Data.Word
import HaskellWorks.Data.AtIndex
import HaskellWorks.Data.Bits.PopCount.PopCount1
import HaskellWorks.Data.FromForeignRegion
import HaskellWorks.Data.RankSelect.Base.Select1
import HaskellWorks.Data.RankSelect.CsPoppy
import HaskellWorks.Hspec.Hedgehog
import Hedgehog
import System.IO.Unsafe
import Test.Hspec

import qualified Data.Vector.Storable      as DVS
import qualified HaskellWorks.Hedgehog.Gen as G
import qualified Hedgehog.Gen              as G
import qualified Hedgehog.Range            as R
import qualified System.Directory          as IO

{-# ANN module ("HLint: ignore Reduce duplication"  :: String) #-}

entries :: [FilePath]
entries = mfilter (".idx" `isSuffixOf`) <$> unsafePerformIO $ IO.getDirectoryContents "data"

spec :: Spec
spec = describe "HaskellWorks.Data.RankSelect.ValidateSpec" $ do
  it "Validate generated" $ requireProperty $ do
    !v <- forAll $ G.storableVector (R.linear 5 100) (G.word64 R.constantBounded)

    let !popCounts = DVS.fromList (scanl (+) 0 (popCount1 <$> DVS.toList v))
    let !bitIndex = makeCsPoppy v

    forM_ [0 .. fromIntegral (DVS.length v - 1)] $ \i -> do
      let !w = v !!! i
      let !lastPopCount = popCounts !!! i

      forM_ [0 .. 63] $ \pw -> do
        let !r0 = rank1 w  pw      + lastPopCount
        let !r1 = rank1 w (pw + 1) + lastPopCount
        let !p = fromIntegral (i * 64) + pw

        when (r0 == r1) $ do
          let !actualP = select1 bitIndex r0
          when (actualP > p) $ do
            annotate $ "actualP[" <> show actualP <> "] > p[" <> show p <> "]"
            failure

    True === True
  describe "Validate data/*.idx" $
    forM_ entries $ \entry ->
      it entry $ requireTest $ do
        !(v :: DVS.Vector Word64) <- liftIO $ mmapFromForeignRegion ("data/" <> entry)
        let !popCounts = DVS.fromList (scanl (+) 0 (popCount1 <$> DVS.toList v))
        let !bitIndex = makeCsPoppy v

        forM_ [0 .. fromIntegral (DVS.length v - 1)] $ \i -> do
          let !w = v !!! i
          let !lastPopCount = popCounts !!! i

          forM_ [0 .. 63] $ \pw -> do
            let !r0 = rank1 w  pw      + lastPopCount
            let !r1 = rank1 w (pw + 1) + lastPopCount
            let !p = fromIntegral (i * 64) + pw

            when (r0 == r1) $ do
              let !actualP = select1 bitIndex r0
              when (actualP > p) $ do
                annotate $ "select1 " <> show r0 <> " == " <> "actualP[" <> show actualP <> "] > p[" <> show p <> "]"
                failure