module WWW.Colors.Instances where

import Clay.Color qualified as Clay
import Data.Colour
import Data.Colour.SRGB (toSRGB24, sRGB24, RGB (..))
import Diagrams.Attributes
import GHC.Float (double2Float, float2Double)


instance Color Clay.Color where
    toAlphaColour :: Clay.Color -> AlphaColour Double
    toAlphaColour col = case Clay.toRgba col of
                            Clay.Rgba r g b a ->
                                let rgb = sRGB24 (fromInteger r) (fromInteger g) (fromInteger b)
                                 in withOpacity rgb (float2Double a)
                            _ -> error "Should not happen"

    fromAlphaColour :: AlphaColour Double -> Clay.Color
    fromAlphaColour col =
        let c = fromAlphaColour col :: Colour Double
            a = alphaChannel col
            rgb = toInteger <$> toSRGB24 c
         in Clay.rgba (channelRed rgb) (channelGreen rgb) (channelBlue rgb) (double2Float a)