import           Graphics.OpenSCAD
import           Linear.V3
import           OpenSCAD.Carpentry
import           System.Process

-- the minimum paramaters to describe a shelf; the width and depth of a shelf,
-- a list consisting of the height of each shelf (from the bottom up).
-- boardThickness is the thickness of the boards to be used
data Shelf = Shelf {
  width          :: Double,
  depth          :: Double,
  shelfHeights   :: [Double],
  boardThickness :: Double
} deriving (Show)

myShelf :: Shelf
myShelf = Shelf { width = 36, depth = 8, boardThickness = 1,
                  shelfHeights = [12, 12, 10, 10, 6, 6, 6] }


calcShelfHeights :: Shelf -> [Double]
calcShelfHeights s = scanl (+) 0 [h + (boardThickness s)|h <- (shelfHeights s)]

modelShelf :: Shelf -> [Model3d]
modelShelf s =
  let sidesPos = [(0,0,0), (boardThickness s + width s, 0, 0)]
      shelvesPos = let ys = scanl (+) 0 [h + boardThickness s|h <- shelfHeights s]
                   in [ (boardThickness s, 0, y) | y <- ys ]
      place' board places = map (\p -> translate p board) places
  in place' sideBoard sidesPos ++ place' shelfBoard shelvesPos
  where shelfHeight = sum (shelfHeights s) + (boardThickness s) *
                      (fromIntegral (length $ shelfHeights s) + 1)
        sideBoard =  box (boardThickness s) (depth s) shelfHeight
        shelfBoard = box (width s) (depth s) (boardThickness s)

modelShelf' :: Shelf -> [Model3d]
modelShelf' s =
  place sideBoard [V3 0 0 0, V3 (boardThickness s + width s) 0 0] ++
  place shelfBoard [(V3 (boardThickness s) 0 z) | z <- shelfZs]
  where shelfHeight = sum (shelfHeights s) + (boardThickness s) *
                  (fromIntegral (length $ shelfHeights s) + 1)
        sideBoard =  V3 (boardThickness s) (depth s) shelfHeight
        shelfBoard = V3 (width s) (depth s) (boardThickness s)
        shelfZs = scanl (+) 0 [h + boardThickness s|h <- (shelfHeights s)]

modelShelf'' :: Shelf -> [Model3d]
modelShelf'' s =
  let sides = placeColored red sideBoard $ at [0, boardThickness s + width s] [0] [0]
      shelves = placeColored blue shelfBoard $ at [(boardThickness s)] [0] shelfZs
  in sides ++ shelves
  where shelfHeight = sum (shelfHeights s) + (boardThickness s) *
                  (fromIntegral (length $ shelfHeights s) + 1)
        sideBoard =  V3 (boardThickness s) (depth s) shelfHeight
        shelfBoard = V3 (width s) (depth s) (boardThickness s)
        shelfZs = scanl (+) 0 [h + (boardThickness s)|h <- (shelfHeights s)]


shelf :: String
shelf = renderL $ modelShelf myShelf
shelf' :: String
shelf' = renderL $ modelShelf' myShelf
shelf'' :: String
shelf'' = renderL $ modelShelf'' myShelf

main :: IO ProcessHandle
main = openTempSCAD $ shelf''