{-# LANGUAGE RecordWildCards #-}
module Graphics.Layout.Box(Border(..), mapX, mapY,
Size(..), mapSizeX, mapSizeY,
PaddedBox(..), zeroBox, lengthBox, mapX', mapY',
width, height, minWidth, minHeight, maxWidth, maxHeight,
Length(..), mapAuto, lowerLength, Zero(..), CastDouble(..)) where
data Border m n = Border {
top :: m, bottom :: m, left :: n, right :: n
}
mapX :: (n -> nn) -> Border m n -> Border m nn
mapY :: (m -> mm) -> Border m n -> Border mm n
mapX cb self = self { left = cb $ left self, right = cb $ right self }
mapY cb self = self { top = cb $ top self, bottom = cb $ bottom self }
data Size m n = Size {inline :: n, block :: m} deriving (Eq, Show)
mapSizeY cb self = Size (inline self) (cb $ block self)
mapSizeX cb self = Size (cb $ inline self) (block self)
data PaddedBox m n = PaddedBox {
min :: Size m n,
max :: Size m n,
size :: Size m n,
padding :: Border m n,
border :: Border m n,
margin :: Border m n
}
zeroBox :: PaddedBox Double Double
zeroBox = PaddedBox {
min = Size 0 0,
max = Size 0 0,
size = Size 0 0,
padding = Border 0 0 0 0,
border = Border 0 0 0 0,
margin = Border 0 0 0 0
}
lengthBox = PaddedBox {
min = Size Auto Auto,
max = Size Auto Auto,
size = Size Auto Auto,
padding = Border zero zero zero zero,
border = Border zero zero zero zero,
margin = Border zero zero zero zero
}
mapX' :: (n -> nn) -> PaddedBox m n -> PaddedBox m nn
mapX' cb PaddedBox {..} = PaddedBox {
min = Size (cb $ inline min) (block min),
size = Size (cb $ inline size) (block size),
max = Size (cb $ inline max) (block max),
padding = mapX cb padding,
border = mapX cb border,
margin = mapX cb margin
}
mapY' :: (m -> mm) -> PaddedBox m n -> PaddedBox mm n
mapY' cb PaddedBox {..} = PaddedBox {
min = Size (inline min) (cb $ block min),
size = Size (inline size) (cb $ block size),
max = Size (inline max) (cb $ block max),
padding = mapY cb padding,
border = mapY cb border,
margin = mapY cb margin
}
width PaddedBox {..} = left margin + left border + left padding +
inline size + right padding + right border + right margin
height PaddedBox {..} = top margin + top border + top padding +
block size + bottom padding + bottom border + bottom margin
minWidth PaddedBox {..} = left margin + left border + left padding +
inline min + right padding + right border + right margin
minHeight PaddedBox {..} = top margin + top border + top padding +
block min + bottom padding + bottom border + bottom margin
maxWidth PaddedBox {..} = left margin + left border + left padding +
inline max + right padding + right border + right margin
maxHeight PaddedBox {..} = top margin + top border + top padding +
block max + bottom padding + bottom border + bottom margin
data Length = Pixels Double | Percent Double | Auto | Preferred | Min deriving Eq
lowerLength :: Double -> Length -> Double
lowerLength _ (Pixels x) = x
lowerLength outerwidth (Percent x) = x * outerwidth
lowerLength _ _ = 0
mapAuto x Auto = Pixels x
mapAuto x Preferred = Pixels x
mapAuto x Min = Pixels x
mapAuto _ x = x
class Zero a where
zero :: a
instance Zero Double where zero = 0
instance Zero Length where zero = Pixels 0
instance (Zero m, Zero n) => Zero (PaddedBox m n) where
zero = PaddedBox {
min = Size zero zero,
max = Size zero zero,
size = Size zero zero,
padding = Border zero zero zero zero,
border = Border zero zero zero zero,
margin = Border zero zero zero zero
}
class CastDouble a where
fromDouble :: Double -> a
instance CastDouble Double where fromDouble = id
instance CastDouble Length where fromDouble = Pixels