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

import Data.Int (Int32)

import Test.Hspec
import System.FilePath ((</>))
import Data.Text.ParagraphLayout
import Data.Text.ParagraphLayout.FontLoader
import Data.Text.ParagraphLayout.Internal.Paginable (paginateAll)
import Data.Text.ParagraphLayout.PrettyShow
import Data.Text.ParagraphLayout.PrettyShow.Golden
import Data.Text.ParagraphLayout.Rect
import Data.Text.ParagraphLayout.Rich
import Data.Text.ParagraphLayout.Rich.ParagraphData

fragmentRects :: ParagraphLayout d -> [(d, Rect Int32)]
fragmentRects p = map toItem $ paragraphFragments p
    where toItem (Fragment { fragmentUserData = d, fragmentRect = r }) = (d, r)

spec :: Spec
spec = do

    describe "layoutRich" $ do
        let
            goldenDir = ".golden" </> "richParagraphLayout"
            shouldBeGolden = goldenTest goldenDir id id

        describe "with Latin font" $ do
            font <- runIO $ loadFont latinFont 0 testingOptions
            fontSmall <- runIO $ loadFont latinFont 0 testingOptionsSmall

            it "wraps lorem ipsum at 20em" $ do
                let opts = defaultParagraphOptions { paragraphMaxWidth = 20000 }
                let input = loremIpsumParagraph font opts
                let result = layoutRich input
                result `shouldBeGolden` "loremIpsum20em"

            it "handles mixed sizes" $ do
                let opts = defaultParagraphOptions
                let input = mixedSizesParagraph (font, fontSmall) opts
                let result = layoutRich input
                result `shouldBeGolden` "mixedSizes"

            it "handles nested boxes" $ do
                let opts = defaultParagraphOptions
                let input = nestedBoxesParagraph font opts
                let result = layoutRich input
                result `shouldBeGolden` "nestedBoxes"

            it "handles hard break in LTR boxes" $ do
                let opts = defaultParagraphOptions
                let input = hardBoxBreakLTRParagraph font opts
                let result = layoutRich input
                result `shouldBeGolden` "hardBoxBreakLTR"

            it "breaks line early if box spacing does not fit" $ do
                let lineH = -1121
                let lineY n = lineH * (n - 1)
                let wordAdvancesWithSpace = [3134, 2954, 2659, 1332, 2601]
                let spaceAdvance = 231
                let wordW n = wordAdvancesWithSpace !! (n - 1)
                let wordW_ n = wordW n - spaceAdvance
                let originX = 0
                let wordX n =
                        originX + (sum $ take (n - 1) wordAdvancesWithSpace)
                let endX = originX + (sum wordAdvancesWithSpace)
                -- A paragraph exactly wide enough to fit the whole text.
                let opts = defaultParagraphOptions { paragraphMaxWidth = endX }
                -- Small spacing that should push one word onto the next line.
                let s = 5
                -- Large spacing that should push two words onto the next line.
                let s' = wordW 5 + spaceAdvance + 1
                let inputNoSpacing = softBreakParagraph 0 font opts
                let inputSmallSpacing = softBreakParagraph s font opts
                let inputLargeSpacing = softBreakParagraph s' font opts
                let resultNoSpacing = layoutRich inputNoSpacing
                let resultSmallSpacing = layoutRich inputSmallSpacing
                let resultLargeSpacing = layoutRich inputLargeSpacing
                fragmentRects resultNoSpacing `shouldBe`
                    [ ("text1", Rect (wordX 1) (lineY 1) (wordW 1) lineH)
                    , ("text2", Rect (wordX 2) (lineY 1) (wordW 2) lineH)
                    , ("text3", Rect (wordX 3) (lineY 1) (wordW 3) lineH)
                    , ("text4", Rect (wordX 4) (lineY 1) (wordW 4) lineH)
                    , ("text5", Rect (wordX 5) (lineY 1) (wordW 5) lineH)
                    ]
                fragmentRects resultSmallSpacing `shouldBe`
                    [ ("text1", Rect (wordX 1) (lineY 1) (wordW 1) lineH)
                    , ("text2", Rect (wordX 2) (lineY 1) (wordW 2) lineH)
                    , ("text3", Rect (wordX 3 + s) (lineY 1) (wordW 3) lineH)
                    , ("text4", Rect (wordX 4 + s) (lineY 1) (wordW_ 4) lineH)
                    , ("text5", Rect originX (lineY 2) (wordW 5) lineH)
                    ]
                fragmentRects resultLargeSpacing `shouldBe`
                    [ ("text1", Rect (wordX 1) (lineY 1) (wordW 1) lineH)
                    , ("text2", Rect (wordX 2) (lineY 1) (wordW 2) lineH)
                    , ("text3", Rect (wordX 3 + s') (lineY 1) (wordW_ 3) lineH)
                    , ("text4", Rect originX (lineY 2) (wordW 4) lineH)
                    , ("text5",
                        Rect (originX + wordW 4) (lineY 2) (wordW 5) lineH)
                    ]

        describe "with Arabic font" $ do
            font <- runIO $ loadFont arabicFont 0 testingOptions

            it "handles hard break in RTL boxes" $ do
                let opts = defaultParagraphOptions
                let input = hardBoxBreakRTLParagraph font opts
                let result = layoutRich input
                result `shouldBeGolden` "hardBoxBreakRTL"

    describe "paginate" $ do
        let
            goldenDir = ".golden" </> "paginatedRichParagraphLayout"
            shouldBeGolden = goldenTest goldenDir getRichPages RichPages

        describe "with Latin font" $ do
            font <- runIO $ loadFont latinFont 0 testingOptions

            it "wraps lorem ipsum at 20em" $ do
                let opts = defaultParagraphOptions { paragraphMaxWidth = 20000 }
                let input = loremIpsumParagraph font opts
                let pl = layoutRich input
                let popts = PageOptions
                        { pageCurrentHeight = 2500
                        , pageNextHeight = 8500
                        , pageOrphans = 2
                        , pageWidows = 3
                        }
                let pages = paginateAll popts pl
                pages `shouldBeGolden` "loremIpsum20em"