{-# LANGUAGE ScopedTypeVariables #-}
module Data.Geometry.IntervalSpec where

import           Control.Lens
import           Data.Ext
import qualified Data.Foldable as F
import           Data.Geometry
import           Data.Geometry.Box
import           Data.Geometry.IntervalTree (IntervalTree)
import qualified Data.Geometry.IntervalTree as IntTree
import           Data.Geometry.SegmentTree (SegmentTree, I(..))
import qualified Data.Geometry.SegmentTree as SegTree
import qualified Data.List.NonEmpty as NonEmpty
import           Data.Range
import qualified Data.Seq as Seq
import qualified Data.Set as Set
import           GHC.TypeLits
import           Test.Hspec
import           Test.Hspec.QuickCheck
import           Test.QuickCheck
import           Test.QuickCheck.HGeometryInstances ()
import           Test.QuickCheck.Instances ()
import           Util

naive   :: (Ord r, Foldable f) => r -> f (Interval p r) -> [Interval p r]
naive q = filter (q `inInterval`) . F.toList

sameAsNaive                 :: (Ord r, Ord p, Foldable f)
                            => f (Interval p r)
                            -> (r -> t -> [Interval p r], t)
                            -> r
                            -> Bool
sameAsNaive is (search,t) q = search q t `sameElems` naive q is


sameElems    :: Eq a => [a] -> [a] -> Bool
sameElems xs = null . difference xs


allSameAsNaive       :: (Ord r, Ord p)
                     => NonEmpty.NonEmpty (Interval p r) -> [r] -> Bool
allSameAsNaive is = all (sameAsNaive is (\q t -> _unI <$> SegTree.search q t
                                        , SegTree.fromIntervals' is))


allSameAsNaiveIT       :: (Ord r, Ord p)
                     => NonEmpty.NonEmpty (Interval p r) -> [r] -> Bool
allSameAsNaiveIT is = all (sameAsNaive is (\q t -> IntTree.search q t
                                         , IntTree.fromIntervals $ F.toList is))

spec :: Spec
spec = modifyMaxSuccess (const 1000) $ do
    describe "Same as Naive" $ do
      it "quickcheck segmentTree" $
        property $ \(Intervals is :: Intervals Word) -> allSameAsNaive is
      it "quickcheck IntervalTree" $
        property $ \(Intervals is :: Intervals Word) -> allSameAsNaiveIT is


newtype Intervals r = Intervals (NonEmpty.NonEmpty (Interval () r)) deriving (Show,Eq)

-- don't generate double open intervals, and don't generate intervals in which
-- one endpoint is open, the other is closed, but at the same point
instance (Arbitrary r, Ord r) => Arbitrary (Intervals r) where
  arbitrary = Intervals . NonEmpty.fromList <$> listOf1 (suchThat arbitrary p)
    where
      p (OpenInterval _ _) = False
      p (Interval s e)     = not (isOpen s /= isOpen e
                                  && s^.unEndPoint.core == e^.unEndPoint.core)