{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE ViewPatterns      #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}

module QC.CIE (tests) where

import           Control.Monad                        (liftM3)
import           Data.Convertible
import           Data.MonoTraversable
import           Data.Prizm.Color
import           Data.Prizm.Color.Transform
import           Test.Framework                       (Test)
import           Test.Framework.Providers.QuickCheck2 as QuickCheck
import           Test.QuickCheck

instance Arbitrary CIEXYZ where
  arbitrary = liftM3 CIEXYZ (choose (0, 95.047)) (choose (0, 100.000)) (choose (0, 108.883))

instance Arbitrary CIELAB where
  arbitrary = liftM3 CIELAB (choose (0, 100)) (choose ((-129), 129)) (choose ((-129), 129))

rN :: Double -> Double
rN = roundN 11

xyz2LAB :: CIEXYZ -> Bool
xyz2LAB ((omap rN ) -> genVal) = genVal == xyz
  where
    ((omap rN) -> xyz) =
      convert ((convert genVal) :: CIELAB)

lab2XYZ :: CIELAB -> Bool
lab2XYZ ((omap rN ) -> genVal) = genVal == lab
  where
    ((omap rN) -> lab) =
      convert ((convert genVal) :: CIEXYZ)

lab2LCH :: CIELAB -> Bool
lab2LCH ((omap rN ) -> genVal) = genVal == lch
  where
    ((omap rN) -> lch) =
      convert ((convert genVal) :: CIELCH)

tests :: [Test]
tests =
  [ QuickCheck.testProperty "CIE XYZ  <-> CIE L*a*b*" xyz2LAB
  , QuickCheck.testProperty "CIE L*ab <-> CIE XYZ   " lab2XYZ
  , QuickCheck.testProperty "CIE L*ab <-> CIE L*Ch  " lab2LCH
  ]