module Tests.Cube
where

import Test.QuickCheck

import Cube (Cube(Cube))
import FunctionValues (FunctionValues(FunctionValues))
import Tests.FunctionValues

instance Arbitrary Cube where
    arbitrary = do
      (Positive h') <- arbitrary :: Gen (Positive Double)
      i' <- choose (coordmin, coordmax)
      j' <- choose (coordmin, coordmax)
      k' <- choose (coordmin, coordmax)
      fv' <- arbitrary :: Gen FunctionValues
      return (Cube h' i' j' k' fv')
        where
          coordmin = -268435456 -- -(2^29 / 2)
          coordmax = 268435456  -- +(2^29 / 2)


-- Quickcheck tests.

-- | Since the grid size is necessarily positive, all tetrahedrons
--   (which comprise cubes of positive volume) must have positive volume
--   as well.
-- prop_all_volumes_positive :: Cube -> Property
-- prop_all_volumes_positive c =
--     (delta > 0) ==> (null nonpositive_volumes)
--     where
--       delta = h (grid c)
--       ts = tetrahedrons c
--       volumes = map volume ts
--       nonpositive_volumes = filter (<= 0) volumes