package Global(
        XCoord, YCoord, XSize, YSize, shiftY, posX, posY, limitY,
        hSize, vSize,
        paddleWidth, paddleHeight, paddleEdgeDist, paddleDistFromWall,
        ballWidth, ballHeight,
        xMin, xMax, yMin, yMax,
        scoreLong, scoreShort, scoreLx, scoreRx, scoreY, NScoreDigits,
        vgaTiming, preScale
        ) where

import VGACore


-- Border width
border :: Integer
border = 10

-- Paddle parameters
paddleDistFromWall :: Integer
paddleDistFromWall = 64
paddleWidth :: Integer
paddleWidth = 16
paddleHeight :: Integer
paddleHeight = 80
paddleEdgeDist :: Integer
paddleEdgeDist = 20+border

-- Ball parameters
-- Width must be smaller than paddle, since we only check corners for hit
ballWidth :: Integer
ballWidth = paddleWidth - 1
ballHeight :: Integer
ballHeight = ballWidth `div` 2

-- Score
scoreLong :: Integer   -- segment length
scoreLong = 40
scoreShort :: Integer  -- segment width
scoreShort = 8

type NScoreDigits = 3

scoreWallDist :: Integer
scoreWallDist = 100

scoreLx :: Integer
scoreLx = xMin + scoreWallDist

scoreRx :: Integer
scoreRx = xMax - (scoreWallDist + (valueOf NScoreDigits) * (scoreLong + scoreShort))

scoreY :: Integer
scoreY = 30

vgaTiming :: VGATiming
vgaTiming = vga1280x480
--vgaTiming = sizeToTiming hSize vSize
--vgaTiming = hzToTiming 50000000

-- Derived values

-- Size of the screen
hSize :: Integer
hSize = 1280 -- 800 -- vgaTiming.h.activeSize
vSize :: Integer
vSize = 480 -- 600 -- vgaTiming.v.activeSize

-- Prescale divides the clock
preScale :: Integer
preScale = 1

-- Playing field
xMin :: Integer
xMin = 2*border
xMax :: Integer
xMax = hSize - 2*border
yMin :: Integer
yMin = border
yMax :: Integer
yMax = vSize - border


-------------------------

type XCoordSize =  12
type YCoordSize =  11

data XCoord = XCoord (Bit XCoordSize)
        deriving (Literal, Eq, Ord, Arith, Bits, Bitwise)
data YCoord = YCoord (Bit YCoordSize)
        deriving (Literal, Eq, Ord, Arith, Bits, Bitwise)

type XSize = XCoord
type YSize = YCoord

shiftY :: YCoord -> Nat -> YCoord
shiftY (YCoord x) s = YCoord ( signedShiftRight x s )

posY :: YCoord -> Bool
posY (YCoord x) = x[fromInteger $ valueOf YCoordSize - 1
                   :fromInteger $ valueOf YCoordSize - 1]==0

posX :: XCoord -> Bool
posX (XCoord x) = x[fromInteger $ valueOf XCoordSize - 1
                   :fromInteger $ valueOf XCoordSize - 1]==0

limitY :: YCoord -> YCoord
limitY (YCoord y) = let limit = 8
                    in if signedLT y (negate limit) then YCoord (negate limit)
                       else if signedLT limit y then YCoord limit
                       else YCoord y