{-# OPTIONS_GHC -fno-warn-incomplete-patterns #-}
{-# LANGUAGE ScopedTypeVariables #-}

module HaskellWorks.Data.Excess.MinMaxExcess1Spec (spec) where

import qualified Data.Vector.Storable                             as DVS
import           Data.Word
import           HaskellWorks.Data.Bits.Word
import           HaskellWorks.Data.Excess.MinMaxExcess1
import           HaskellWorks.Data.Naive
import           Test.Hspec
import           Test.QuickCheck

{-# ANN module ("HLint: Ignore Redundant do" :: String) #-}
{-# ANN module ("HLint: Ignore Reduce duplication"  :: String) #-}

spec :: Spec
spec = describe "HaskellWorks.Data.Excess.MinMaxExcess1Spec" $ do
  describe "For Word8" $ do
    it "Excess should be between min excess and max excess" $
      property $ \(w :: Word8) ->
        let (minE, e, maxE) = minMaxExcess1 w in
        minE <= e && e <= maxE
    it "minE2 == minE0 `min` (minE1 + e0)" $
      property $ \(w0 :: Word8, w1 :: Word8) ->
        let w2 = leConcat w0 w1 in
        let (minE0, e0, _) = minMaxExcess1 w0 in
        let (minE1, _ , _) = minMaxExcess1 w1 in
        let (minE2, _ , _) = minMaxExcess1 w2 in
        minE2 == minE0 `min` (minE1 + e0)
    it "maxE2 == maxE0 `max` (maxE1 + e0)" $
      property $ \(w0 :: Word8, w1 :: Word8) ->
        let w2 = leConcat w0 w1 in
        let (_, e0, maxE0) = minMaxExcess1 w0 in
        let (_, _ , maxE1) = minMaxExcess1 w1 in
        let (_, _ , maxE2) = minMaxExcess1 w2 in
        maxE2 == maxE0 `max` (maxE1 + e0)
    it "minE2 == minE0 `min` (minE1 + e0) via vector" $
      property $ \(w0 :: Word8, w1 :: Word8) ->
        let w2 = DVS.fromList [w0, w1] in
        let (minE0, e0, _) = minMaxExcess1 w0 in
        let (minE1, _ , _) = minMaxExcess1 w1 in
        let (minE2, _ , _) = minMaxExcess1 w2 in
        minE2 == minE0 `min` (minE1 + e0)
    it "maxE2 == maxE0 `max` (maxE1 + e0) via vector" $
      property $ \(w0 :: Word8, w1 :: Word8) ->
        let w2 = DVS.fromList [w0, w1] in
        let (_, e0, maxE0) = minMaxExcess1 w0 in
        let (_, _ , maxE1) = minMaxExcess1 w1 in
        let (_, _ , maxE2) = minMaxExcess1 w2 in
        maxE2 == maxE0 `max` (maxE1 + e0)
  describe "For Word16" $ do
    it "Excess should be between min excess and max excess" $
      property $ \(w :: Word16) ->
        let (minE, e, maxE) = minMaxExcess1 w in
        minE <= e && e <= maxE
    it "minE2 == minE0 `min` (minE1 + e0)" $
      property $ \(w0 :: Word16, w1 :: Word16) ->
        let w2 = leConcat w0 w1 in
        let (minE0, e0, _) = minMaxExcess1 w0 in
        let (minE1, _ , _) = minMaxExcess1 w1 in
        let (minE2, _ , _) = minMaxExcess1 w2 in
        minE2 == minE0 `min` (minE1 + e0)
    it "maxE2 == maxE0 `max` (maxE1 + e0)" $
      property $ \(w0 :: Word16, w1 :: Word16) ->
        let w2 = leConcat w0 w1 in
        let (_, e0, maxE0) = minMaxExcess1 w0 in
        let (_, _ , maxE1) = minMaxExcess1 w1 in
        let (_, _ , maxE2) = minMaxExcess1 w2 in
        maxE2 == maxE0 `max` (maxE1 + e0)
    it "minE2 == minE0 `min` (minE1 + e0) via vector" $
      property $ \(w0 :: Word16, w1 :: Word16) ->
        let w2 = DVS.fromList [w0, w1] in
        let (minE0, e0, _) = minMaxExcess1 w0 in
        let (minE1, _ , _) = minMaxExcess1 w1 in
        let (minE2, _ , _) = minMaxExcess1 w2 in
        minE2 == minE0 `min` (minE1 + e0)
    it "maxE2 == maxE0 `max` (maxE1 + e0) via vector" $
      property $ \(w0 :: Word16, w1 :: Word16) ->
        let w2 = DVS.fromList [w0, w1] in
        let (_, e0, maxE0) = minMaxExcess1 w0 in
        let (_, _ , maxE1) = minMaxExcess1 w1 in
        let (_, _ , maxE2) = minMaxExcess1 w2 in
        maxE2 == maxE0 `max` (maxE1 + e0)
    describe "For Word32" $ do
      it "Excess should be between min excess and max excess" $
        property $ \(w :: Word32) ->
          let (minE, e, maxE) = minMaxExcess1 w in
          minE <= e && e <= maxE
      it "minE2 == minE0 `min` (minE1 + e0)" $
        property $ \(w0 :: Word32, w1 :: Word32) ->
          let w2 = leConcat w0 w1 in
          let (minE0, e0, _) = minMaxExcess1 w0 in
          let (minE1, _ , _) = minMaxExcess1 w1 in
          let (minE2, _ , _) = minMaxExcess1 w2 in
          minE2 == minE0 `min` (minE1 + e0)
      it "maxE2 == maxE0 `max` (maxE1 + e0)" $
        property $ \(w0 :: Word32, w1 :: Word32) ->
          let w2 = leConcat w0 w1 in
          let (_, e0, maxE0) = minMaxExcess1 w0 in
          let (_, _ , maxE1) = minMaxExcess1 w1 in
          let (_, _ , maxE2) = minMaxExcess1 w2 in
          maxE2 == maxE0 `max` (maxE1 + e0)
      it "minE2 == minE0 `min` (minE1 + e0) via vector" $
        property $ \(w0 :: Word32, w1 :: Word32) ->
          let w2 = DVS.fromList [w0, w1] in
          let (minE0, e0, _) = minMaxExcess1 w0 in
          let (minE1, _ , _) = minMaxExcess1 w1 in
          let (minE2, _ , _) = minMaxExcess1 w2 in
          minE2 == minE0 `min` (minE1 + e0)
      it "maxE2 == maxE0 `max` (maxE1 + e0) via vector" $
        property $ \(w0 :: Word32, w1 :: Word32) ->
          let w2 = DVS.fromList [w0, w1] in
          let (_, e0, maxE0) = minMaxExcess1 w0 in
          let (_, _ , maxE1) = minMaxExcess1 w1 in
          let (_, _ , maxE2) = minMaxExcess1 w2 in
          maxE2 == maxE0 `max` (maxE1 + e0)
  describe "For Word64" $ do
    it "Excess should be between min excess and max excess" $
      property $ \(w :: Word64) ->
        let (minE, e, maxE) = minMaxExcess1 w in
        minE <= e && e <= maxE
    it "minE2 == minE0 `min` (minE1 + e0) via vector" $
      property $ \(w0 :: Word64, w1 :: Word64) ->
        let w2 = DVS.fromList [w0, w1] in
        let (minE0, e0, _) = minMaxExcess1 w0 in
        let (minE1, _ , _) = minMaxExcess1 w1 in
        let (minE2, _ , _) = minMaxExcess1 w2 in
        minE2 == minE0 `min` (minE1 + e0)
    it "maxE2 == maxE0 `max` (maxE1 + e0) via vector" $
      property $ \(w0 :: Word64, w1 :: Word64) ->
        let w2 = DVS.fromList [w0, w1] in
        let (_, e0, maxE0) = minMaxExcess1 w0 in
        let (_, _ , maxE1) = minMaxExcess1 w1 in
        let (_, _ , maxE2) = minMaxExcess1 w2 in
        maxE2 == maxE0 `max` (maxE1 + e0)
  describe "Equivalent to native implementation" $ do
    it "For Word8" $ do
      property $ \(w :: Word8) ->
        minMaxExcess1 w == minMaxExcess1 (Naive w)
    it "For Word16" $ do
      property $ \(w :: Word16) ->
        minMaxExcess1 w == minMaxExcess1 (Naive w)
    it "For Word32" $ do
      property $ \(w :: Word32) ->
        minMaxExcess1 w == minMaxExcess1 (Naive w)
    it "For Word64" $ do
      property $ \(w :: Word64) ->
        minMaxExcess1 w == minMaxExcess1 (Naive w)