module Main where

import Numeric.Qhull
import Control.Parallel.Strategies
import qualified Data.Vector.Unboxed as UV
import qualified Data.Vector.Storable as SV
import qualified Data.Vector as V
import Data.Either
import Data.List

readPoints :: String -> [UV.Vector Double]
readPoints s = map (UV.fromList . (map read) . words) (lines s)

simplexToString :: SV.Vector Int -> String
simplexToString x = concat $ intersperse " " (map show (SV.toList x))

main :: IO ()
main = getContents >>= \input ->
       let
           points = V.fromList (readPoints input)
           facets = either id (const []) (qhull' points)
           facets' = map (\fids -> V.map (\i -> points V.! i) (SV.convert fids)) facets
           output = unlines $ map simplexToString facets
       in
       putStr output >>
       putStrLn ((either show errorMessage) (qhull'' testPoints2))
                   

testPoints :: [[Double]]
testPoints = [[0,0],
              [1,1],
              [-1,1],
              [-1,-1],
              [1,-1]
             ] 

testPoints2 :: [[Double]]
testPoints2 = [[0,0,0],
               [1,1,0],
               [-1,1,0],
               [-1,-1,0],
               [1,-1,0]
              ] 


testCube :: [[Double]]
testCube = [[0,  0, 0],
            [1,  1, 1],
            [1, -1, 1],
            [-1, 1, 1],
            [1, 1, -1],
            [-1, -1, 1],
            [-1, 1, -1],
            [1, -1, -1],
            [-1,-1,-1]
           ]