{-# OPTIONS_GHC -XTypeSynonymInstances #-}
{-
Copyright (c) 2008
Russell O'Connor

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
-}
module Main where

import Data.Word
import Control.Monad
import Test.QuickCheck
import Text.Printf
import Data.Monoid

import Data.Colour.Matrix
import Data.Colour
import Data.Colour.Internal hiding (RGB)
import Data.Colour.Chan (Chan(..))
import Data.Colour.CIE.Chromaticity
import Data.Colour.SRGB
import Data.Colour.CIE
import Data.Colour.Names
import Data.Colour.HDTV as HDTV
import Data.Colour.RGB
import Data.Colour.RGBSpace

default (Rational, Double, Float)

type RColour = Colour Rational
type DColour = Colour Double
type FColour = Colour Float
type RAlphaColour = AlphaColour Rational
type DAlphaColour = AlphaColour Double

instance Arbitrary Word8 where
  arbitrary = liftM fromIntegral $
              choose (fromIntegral (minBound::Word8)::Int,
                      fromIntegral (maxBound::Word8)::Int)
  coarbitrary x = variant (fromIntegral x)

instance Arbitrary (Rational) where
  arbitrary = liftM (toRational :: Double -> Rational) $ arbitrary
  coarbitrary x = coarbitrary (fromRational x :: Double)

instance (Real a, Fractional a, Arbitrary a) => Arbitrary (Colour a) where
  arbitrary = liftM3 mkColour arbitrary arbitrary arbitrary
   where
    mkColour r' g' b' = colourConvert (sRGB24 r' g' b'::Colour Double)
  coarbitrary c = coarbitrary (r,g,b)
   where
    (RGB r g b) = toRGB709 c

instance (Real a, Fractional a, Arbitrary a) =>
         Arbitrary (AlphaColour a) where
  arbitrary = liftM2 mkAlphaColour arbitrary arbitrary
   where
    mkAlphaColour :: (Fractional a) => Colour a -> Word8 -> AlphaColour a
    mkAlphaColour c a =
      c `withOpacity` (fromIntegral a/fromIntegral (maxBound `asTypeOf` a))
  coarbitrary ac = coarbitrary a . coarbitrary c
   where
    a = alphaChannel ac
    c = ac `over` mempty
    d = opaque c `asTypeOf` ac -- to help the type sytem

instance (Fractional a, Arbitrary a) =>
         Arbitrary (Chromaticity a) where
  arbitrary = liftM2 cieChroma arbitrary arbitrary
  coarbitrary c = coarbitrary x . coarbitrary y
   where
    (x,y,_) = chroma_coords c

instance (Arbitrary a) => Arbitrary (RGB a) where
  arbitrary = liftM3 RGB arbitrary arbitrary arbitrary
  coarbitrary (RGB r g b) = coarbitrary (r,g,b)

instance (Fractional a, Arbitrary a) =>
         Arbitrary (RGBSpace a) where
  arbitrary = liftM2 RGBSpace arbitrary arbitrary
  coarbitrary (RGBSpace p w) = coarbitrary p . coarbitrary w

instance (Fractional a) => Show (Colour a) where
  showsPrec d c = showParen (d > app_prec) showStr
   where
    showStr = showString "rgb709 " . (showsPrec (app_prec+1) r)
            . showString " "       . (showsPrec (app_prec+1) g)
            . showString " "       . (showsPrec (app_prec+1) b)
    Data.Colour.RGB.RGB r g b = toRGB709 c

instance (Fractional a, Read a) => Read (Colour a) where
  readsPrec d r = readParen (d > app_prec)
                  (\r -> [(rgb709 r0 g0 b0,t)
                         |("rgb709",s) <- lex r
                         ,(r0,s0) <- readsPrec (app_prec+1) s
                         ,(g0,s1) <- readsPrec (app_prec+1) s0
                         ,(b0,t)  <- readsPrec (app_prec+1) s1]) r

instance (Fractional a) => Show (AlphaColour a) where
  showsPrec d ac = showParen (d > infix_prec) showStr
   where
    showStr | a == 0 = showString "transparent"
            | otherwise = showsPrec (infix_prec+1) c
                        . showString " `withOpacity` "
                        . showsPrec (infix_prec+1) a
    a = alphaChannel ac
    c = colourChannel ac

instance (Fractional a, Read a) => Read (AlphaColour a) where
  readsPrec d r = [(transparent,s)|("transparent",s) <- lex r]
               ++ readParen (d > infix_prec)
                  (\r -> [(c `withOpacity` o,s)
                         |(c,r0) <- readsPrec (infix_prec+1) r
                         ,("`",r1) <- lex r0
                         ,("withOpacity",r2) <- lex r1
                         ,("`",r3) <- lex r2
                         ,(o,s)  <- readsPrec (infix_prec+1) r3]) r

-- |Returns the colour of an 'AlphaColour'.
-- @colourChannel transparent@ is undefined and may result in @nan@ or an
-- error.
-- Its use is discouraged.
-- If you are desparate, use
--
-- >darken (recip (alphaChannel c)) (c `over` black)
colourChannel :: (Fractional a) => AlphaColour a -> Colour a
colourChannel (RGBA c (Chan a)) = darken (recip a) c


good (RGBSpace p w) = p1 && p2
 where
  p1 = 0 /= determinant (primaryMatrix p)
  p2 = 0 /= let (x,y,z) = chroma_coords w in y

prop_matrixMult (a1,b1,c1) (d1,e1,f1) (g1,h1,i1)
                (a2,b2,c2) (d2,e2,f2) (g2,h2,i2)
                (x,y,z) = mult m1 (mult m2 v) == mult (matrixMult m1 m2) v
 where 
  m1 = [[a1,b1,c1],[d1,e1,f1],[g1,h1,i1]]
  m2 = [[a2,b2,c2],[d2,e2,f2],[g2,h2,i2]]
  v :: [Rational]
  v = [x,y,z]

prop_toFromRGB709 :: RColour -> Bool
prop_toFromRGB709 c = uncurryRGB rgb709 (toRGB709 c) == c

prop_fromToRGB709 :: Rational -> Rational -> Rational -> Bool
prop_fromToRGB709 r g b = toRGB709 (rgb709 r g b) == RGB r g b

prop_toFromXYZ :: RColour -> Bool
prop_toFromXYZ c = (cieXYZ x y z) == c
 where
  (x,y,z) = toCIEXYZ c

prop_fromToXYZ :: Rational -> Rational -> Rational -> Bool
prop_fromToXYZ x y z = toCIEXYZ (cieXYZ x y z) == (x,y,z)

-- Uses the fact that an Arbitrary colour is an sRGB24 colour.
prop_toFromSRGB :: DColour -> Bool
prop_toFromSRGB c = uncurryRGB sRGB24 (toSRGB24 c) == c

prop_fromToSRGB :: Word8 -> Word8 -> Word8 -> Bool
prop_fromToSRGB r' g' b' = toSRGB24 (sRGB24 r' g' b') == RGB r' g' b'

prop_fromToY'CbCr709 :: Word8 -> Word8 -> Word8 -> Bool
prop_fromToY'CbCr709 y' cb cr =
  HDTV.toY'CbCr (HDTV.y'CbCr y' cb cr) == (y',cb,cr)

{-
prop_fromToY'CbCr601 :: Word8 -> Word8 -> Word8 -> Bool
prop_fromToY'CbCr601 y' cb cr =
  SDTV.toY'CbCr (SDTV.y'CbCr y' cb cr) == (y',cb,cr)
-}

prop_disolveId :: RAlphaColour -> Bool
prop_disolveId c = disolve 1 c == c

prop_disolveTransparent :: RAlphaColour -> Bool
prop_disolveTransparent c = disolve 0 c == transparent

prop_transparentOver :: RColour -> Bool
prop_transparentOver c = transparent `over` c == c

prop_overTransparent :: RAlphaColour -> Bool
prop_overTransparent c = c `over` transparent == c

prop_opaqueOver :: RColour -> RColour -> Bool
prop_opaqueOver c1 c2 = opaque c1 `over` c2 == c1

prop_overOpaque :: RAlphaColour -> RColour -> Bool
prop_overOpaque c1 c2 = c1 `over` opaque c2 == opaque (c1 `over` c2)

prop_blendOver :: Rational -> RColour -> RColour -> Bool
prop_blendOver o c1 c2 = 
  (c1 `withOpacity` o) `over` c2 == blend o c1 c2

prop_blendTransparent :: Rational -> Rational -> RColour -> Bool
prop_blendTransparent o a c = 
  blend o (c `withOpacity` a) transparent == c `withOpacity ` (o*a)

prop_blendFlip :: Rational -> RColour -> RColour -> Bool
prop_blendFlip o c1 c2 = 
  blend (1-o) c2 c1 == blend o c1 c2

prop_darkenBlend :: Rational -> RColour -> Bool
prop_darkenBlend w c = 
  blend w c mempty == darken w c

prop_darkenBlack :: RAlphaColour -> Bool
prop_darkenBlack c = darken 0 c == mempty `withOpacity` (alphaChannel c)

prop_darkenId :: RAlphaColour -> Bool
prop_darkenId c = darken 1 c == c

prop_atopOpaque :: RAlphaColour -> RColour -> Bool
prop_atopOpaque c0 c1 = c0 `atop` (opaque c1) == opaque (c0 `over` c1)

prop_transparentAtop :: RAlphaColour -> Bool
prop_transparentAtop c = transparent `atop` c == c

prop_atopTransparent :: RAlphaColour -> Bool
prop_atopTransparent c = c `atop` transparent == transparent

prop_atopAlpha :: RAlphaColour -> RAlphaColour -> Bool
prop_atopAlpha c0 c1 = alphaChannel (c0 `atop` c1) == alphaChannel c1

prop_showReadC :: RColour -> Bool
prop_showReadC c = read (show c) == c

prop_showReadAC :: RAlphaColour -> Bool
prop_showReadAC c = read (show c) == c

prop_sRGB24showlength :: DColour -> Bool
prop_sRGB24showlength c = length (sRGB24show c) == 7

prop_readshowSRGB24 :: DColour -> Bool
prop_readshowSRGB24 c =
  sRGB24show (sRGB24read (sRGB24show c)) == sRGB24show c

{-
prop_luminance_white :: RGBSpace Rational -> Property
prop_luminance_white space =
  good space ==> luminance (rgbSpace space 1 1 1) == 1

prop_rgb709 :: Rational -> Rational -> Rational -> Bool
prop_rgb709 r g b =
  rgbSpace rgb709Space r g b == rgb709 r g b

prop_toRGB709 :: RColour -> Bool
prop_toRGB709 c =
  toRGBSpace rgb709Space c == toRGB709 c
-}
tests = [("matrix-mult", test prop_matrixMult)
        ,("RGB709-to-from", test prop_toFromRGB709)
        ,("RGB709-from-to", test prop_fromToRGB709)
        ,("XYZ-to-from", test prop_toFromXYZ)
        ,("XYZ-from-to", test prop_fromToXYZ)
        ,("sRGB-to-from", test prop_toFromSRGB)
        ,("sRGB-from-to", test prop_fromToSRGB)
        ,("Y'CbCr-709-from-to", test prop_fromToY'CbCr709)
--        ,("Y'CbCr-601-from-to", test prop_fromToY'CbCr601)
        ,("disolve-id", test prop_disolveId)
        ,("disolve-transparent", test prop_disolveTransparent)
        ,("transparent-over", test prop_transparentOver)
        ,("over-transparent", test prop_overTransparent)
        ,("opaque-over", test prop_opaqueOver)
        ,("over-opaque", test prop_overOpaque)
        ,("blend-over", test prop_blendOver)
        ,("blend-transparent", test prop_blendTransparent)
        ,("blend-flip", test prop_blendFlip)
        ,("darken-blend", test prop_darkenBlend)
        ,("darken-black", test prop_darkenBlack)
        ,("darken-id", test prop_darkenId)
        ,("atop-opaque", test prop_atopOpaque)
        ,("trasnparent-atop", test prop_transparentAtop)
        ,("atop-transparent", test prop_atopTransparent)
        ,("atop-alpha", test prop_atopAlpha)
        ,("colour-show-read", test prop_showReadC)
        ,("alphaColour-show-read", test prop_showReadAC)
        ,("sRGB24-show-length", test prop_sRGB24showlength)
        ,("sRGB24-read-show", test prop_readshowSRGB24)
--        ,("luminance-white", test prop_luminance_white)
--        ,("rgb709", test prop_rgb709)
--        ,("toRGB709", test prop_toRGB709)
        ]

main  = mapM_ (\(s,a) -> printf "%-25s: " s >> a) tests