import Test.QuickCheck

import Dodge.LevelGen.StaticWalls
import Geometry

main :: IO ()
main = do
    putStrLn "Running tests:"
    quickCheck prop_looping

nextPair :: Eq a => (a,a) -> [(a,a)] -> [(a,a)]
nextPair (_,y) = filter (\(x,_) -> x == y)

isLooping :: Eq a => [(a,a)] -> Bool
isLooping xs = all (( == 1) . length . flip nextPair xs) xs

isLooping' :: Eq a => [(a,a)] -> Bool
isLooping' xs = all (f xs) xs
  where
    f ys (x,y) = length ins == length outs && length rins == length routs
      where
        ins = filter (\(a,b) -> a == x) ys
        outs = filter (\(a,b) -> b == x) ys
        rins = filter (\(a,b) -> a == y) ys
        routs = filter (\(a,b) -> b == y) ys

polygonStrictlyConvex :: [Point2] -> Bool
polygonStrictlyConvex ps = True

--prop_looping :: [Point2] -> [WallP] -> Bool

prop_looping = forAllShrink genTris shrinkTris $ \tris ->
    (all (not . (\[a,b,c] -> isOnSeg a b c
                            || isOnSeg a c b
                            || isOnSeg b c a
                ) ) tris)
    ==> (isLooping' $ foldr cutWalls' [] tris)

shrinkTris [] = []
shrinkTris (x:xs) = xs : map (x :) (shrinkTris xs)

genTri = zip <$> trip <*> trip 
  where
    trip = vectorOf 3 $ fmap fromIntegral $ choose (0,3::Int)

genTris = listOf genTri

--extractLoops :: Eq a => [(a,a)] -> [[(a,a)]]
--extractLoops [] = []
--extractLoops (x:xs) = 
  
--
--[[(0.0,1.0),(3.0,4.0),(5.0,5.0)],[(2.0,0.0),(2.0,4.0),(1.0,1.0)],[(5.0,5.0),(2.0,2.0),(1.0,3.0)]]