module SplitSpec where

import Test.Hspec
import Test.Hspec.QuickCheck
import Test.QuickCheck hiding (Fixed)
import Data.Text.Arbitrary ()

import Control.Comonad.Cofree
import Control.Monad.Free hiding (unfold)
<<<<<<< HEAD
import qualified Data.Set as Set
import Diff
=======
import qualified Data.Maybe as Maybe
import Source hiding ((++))
import Line
import Row
>>>>>>> origin/master
import Patch
import Range
import Split
import Syntax
import ArbitraryTerm

instance Arbitrary a => Arbitrary (Row a) where
  arbitrary = oneof [
    Row <$> arbitrary <*> arbitrary ]

instance Arbitrary a => Arbitrary (Line a) where
  arbitrary = oneof [
    makeLine <$> arbitrary,
    const EmptyLine <$> (arbitrary :: Gen ()) ]

instance Arbitrary a => Arbitrary (Source a) where
  arbitrary = fromList <$> arbitrary

arbitraryLeaf :: Gen (Source Char, Info, Syntax (Source Char) f)
arbitraryLeaf = toTuple <$> arbitrary
  where toTuple string = (string, Info (Range 0 $ length string) mempty, Leaf string)

spec :: Spec
spec = do
  describe "splitAnnotatedByLines" $ do
    prop "outputs one row for single-line unchanged leaves" $
      forAll (arbitraryLeaf `suchThat` isOnSingleLine) $
        \ (source, info@(Info range categories), syntax) -> splitAnnotatedByLines (source, source) (range, range) (categories, categories) syntax `shouldBe` [
          Row (makeLine [ Free $ Annotated info $ Leaf source ]) (makeLine [ Free $ Annotated info $ Leaf source ]) ]

    prop "outputs one row for single-line empty unchanged indexed nodes" $
      forAll (arbitrary `suchThat` (\ a -> filter (/= '\n') (toList a) == toList a)) $
          \ source -> splitAnnotatedByLines (source, source) (getTotalRange source, getTotalRange source) (mempty, mempty) (Indexed [] :: Syntax String (Diff String Info)) `shouldBe` [
            Row (makeLine [ Free $ Annotated (Info (getTotalRange source) mempty) $ Indexed [] ]) (makeLine [ Free $ Annotated (Info (getTotalRange source) mempty) $ Indexed [] ]) ]

    prop "preserves line counts in equal sources" $
      \ source ->
        length (splitAnnotatedByLines (source, source) (getTotalRange source, getTotalRange source) (mempty, mempty) (Indexed . fst $ foldl combineIntoLeaves ([], 0) source)) `shouldBe` length (filter (== '\n') $ toList source) + 1

    prop "produces the maximum line count in inequal sources" $
      \ sourceA sourceB ->
        length (splitAnnotatedByLines (sourceA, sourceB) (getTotalRange sourceA, getTotalRange sourceB) (mempty, mempty) (Indexed $ zipWith (leafWithRangesInSources sourceA sourceB) (actualLineRanges (getTotalRange sourceA) sourceA) (actualLineRanges (getTotalRange sourceB) sourceB))) `shouldBe` max (length (filter (== '\n') $ toList sourceA) + 1) (length (filter (== '\n') $ toList sourceB) + 1)

  describe "adjoinRowsBy" $ do
    prop "is identity on top of no rows" $
      \ a -> adjoinRowsBy openMaybe openMaybe [] a == [ a ]

    prop "appends onto open rows" $
      forAll ((arbitrary `suchThat` isOpenBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openMaybe)) $
        \ (a@(Row a1 b1), b@(Row a2 b2)) ->
          adjoinRowsBy openMaybe openMaybe [ a ] b `shouldBe` [ Row (makeLine $ unLine a1 ++ unLine a2) (makeLine $ unLine b1 ++ unLine b2) ]

    prop "does not append onto closed rows" $
      forAll ((arbitrary `suchThat` isClosedBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openMaybe)) $
        \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ a ] b `shouldBe` [ b, a ]

    prop "does not promote elements through empty lines onto closed lines" $
      forAll ((arbitrary `suchThat` isClosedBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openMaybe)) $
        \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]

    prop "promotes elements through empty lines onto open lines" $
      forAll ((arbitrary `suchThat` isOpenBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openMaybe)) $
        \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openMaybe openMaybe [ a ] b

  describe "splitTermByLines" $ do
    prop "preserves line count" $
      \ source -> let range = getTotalRange source in
        splitTermByLines (Info range mempty :< Leaf source) source `shouldBe` (makeLine . (:[]) . (:< Leaf source) . (`Info` mempty) <$> actualLineRanges range source, range)

  describe "openLineBy" $ do
    it "produces the earliest non-empty line in a list, if open" $
      openLineBy (openTerm $ fromList "\n ") [
        makeLine [ Info (Range 1 2) mempty :< Leaf "" ],
        makeLine [ Info (Range 0 1) mempty :< Leaf "" ]
      ] `shouldBe` (Just $ makeLine [ Info (Range 1 2) mempty :< Leaf "" ])

    it "returns Nothing if the earliest non-empty line is closed" $
      openLineBy (openTerm $ fromList "\n") [
        makeLine [ Info (Range 0 1) mempty :< Leaf "" ]
      ] `shouldBe` Nothing

  describe "openTerm" $ do
    it "returns Just the term if its substring does not end with a newline" $
      let term = Info (Range 0 2) mempty :< Leaf "" in openTerm (fromList "  ") term `shouldBe` Just term

    it "returns Nothing for terms whose substring ends with a newline" $
      openTerm (fromList " \n") (Info (Range 0 2) mempty :< Leaf "") `shouldBe` Nothing

    where
      isOpenBy f (Row a b) = Maybe.isJust (openLineBy f [ a ]) && Maybe.isJust (openLineBy f [ b ])
      isClosedBy f (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy f [ a ]) && Maybe.isNothing (openLineBy f [ b ])
      isClosedBy _ (Row _ _) = False

      isOnSingleLine (a, _, _) = filter (/= '\n') (toList a) == toList a

      getTotalRange (Source vector) = Range 0 $ length vector

      combineIntoLeaves (leaves, start) char = (leaves ++ [ Free $ Annotated (Info (Range start $ start + 1) mempty, Info (Range start $ start + 1) mempty) (Leaf [ char ]) ], start + 1)

      leafWithRangesInSources sourceA sourceB rangeA rangeB = Free $ Annotated (Info rangeA mempty, Info rangeB mempty) (Leaf $ toList sourceA ++ toList sourceB)

      openMaybe :: Maybe Bool -> Maybe (Maybe Bool)
      openMaybe (Just a) = Just (Just a)
      openMaybe Nothing =  Nothing