module Data.Text.ParagraphLayout.RectSpec (spec) where

import Data.Int (Int32)
import Data.List.NonEmpty (NonEmpty ((:|)))

import Test.Hspec
import Data.Text.ParagraphLayout.Internal.Rect

positiveRect :: Rect Int32
positiveRect = Rect 50 (-70) 10 10

negativeRect :: Rect Int32
negativeRect = Rect 80 (-75) (-15) (-15)

spec :: Spec
spec = do

    describe "union of two rects" $ do

        describe "low X, low Y" $
            llSpec $ union LL positiveRect negativeRect

        describe "low X, high Y" $
            lhSpec $ union LH positiveRect negativeRect

        describe "high X, low Y" $
            hlSpec $ union HL positiveRect negativeRect

        describe "high X, high Y" $
            hhSpec $ union HH positiveRect negativeRect

    describe "union of list" $ do

        describe "when empty" $
            it "should be Nothing" $ do
                unionMany LL []
                    `shouldBe` (Nothing :: Maybe (Rect Int32))

        describe "with single item" $ do

            describe "matching LL origin" $
                it "should be identity" $
                    unionMany LL [positiveRect]
                        `shouldBe` Just positiveRect

            describe "matching HH origin" $
                it "should be identity" $
                    unionMany HH [negativeRect]
                        `shouldBe` Just negativeRect

        describe "with single item repeated" $ do

            describe "matching LL origin" $
                it "should be equal to item" $
                    unionMany LL (replicate 2 positiveRect)
                        `shouldBe` Just positiveRect

            describe "matching HH origin" $
                it "should be equal to item" $
                    unionMany HH (replicate 7 negativeRect)
                        `shouldBe` Just negativeRect

        describe "with two items" $
            it "should behave the same as binary function" $
                unionMany LL [positiveRect, negativeRect]
                    `shouldBe` Just (union LL positiveRect negativeRect)

    describe "union of non-empty list" $ do

        describe "with single item" $ do

            describe "matching LL origin" $
                it "should be identity" $
                    unionMany1 LL (positiveRect :| [])
                        `shouldBe` positiveRect

            describe "matching HH origin" $
                it "should be identity" $
                    unionMany1 HH (negativeRect :| [])
                        `shouldBe` negativeRect

        describe "with two items" $
            it "should behave the same as binary function" $
                unionMany1 LL (positiveRect :| [negativeRect])
                    `shouldBe` union LL positiveRect negativeRect

llSpec :: Rect Int32 -> SpecWith ()
llSpec r = do
    commonSpec r
    it "has origin at 50,-90" $
        (x_origin r, y_origin r) `shouldBe` (50, -90)
    it "has terminus at 80,-60" $
        (x_terminus r, y_terminus r) `shouldBe` (80, -60)
    it "has size 30,30" $
        (x_size r, y_size r) `shouldBe` (30, 30)

lhSpec :: Rect Int32 -> SpecWith ()
lhSpec r = do
    commonSpec r
    it "has origin at 50,-60" $
        (x_origin r, y_origin r) `shouldBe` (50, -60)
    it "has terminus at 80,-90" $
        (x_terminus r, y_terminus r) `shouldBe` (80, -90)
    it "has size 30,-30" $
        (x_size r, y_size r) `shouldBe` (30, -30)

hlSpec :: Rect Int32 -> SpecWith ()
hlSpec r = do
    commonSpec r
    it "has origin at 80,-90" $
        (x_origin r, y_origin r) `shouldBe` (80, -90)
    it "has terminus at 50,-60" $
        (x_terminus r, y_terminus r) `shouldBe` (50, -60)
    it "has size -30,30" $
        (x_size r, y_size r) `shouldBe` (-30, 30)

hhSpec :: Rect Int32 -> SpecWith ()
hhSpec r = do
    commonSpec r
    it "has origin at 80,-60" $
        (x_origin r, y_origin r) `shouldBe` (80, -60)
    it "has terminus at 50,-90" $
        (x_terminus r, y_terminus r) `shouldBe` (50, -90)
    it "has size -30,-30" $
        (x_size r, y_size r) `shouldBe` (-30, -30)

commonSpec :: Rect Int32 -> SpecWith ()
commonSpec r = do
    it "has minimum coordinates at at 50,-90" $
        (x_min r, y_min r) `shouldBe` (50, -90)
    it "has maximum coordinates at 80,-60" $
        (x_max r, y_max r) `shouldBe` (80, -60)
    it "has absolute size 30,30" $
        (width r, height r) `shouldBe` (30, 30)