{-# LANGUAGE OverloadedRecordDot #-}

module Zettel.Render where

import Data.Default (def)
import qualified Data.Map.Strict as Map
import qualified Data.Text as T
import Paths_org_zk (getDataFileName)
import Text.Pandoc.Class (runIOorExplode)
import Text.Pandoc.Definition (Block (..), Inline (..))
import Text.Pandoc.Options (WriterOptions (..), multimarkdownExtensions)
import Text.Pandoc.Templates (WithDefaultPartials (..), compileTemplate)
import Text.Pandoc.Writers (writeMarkdown)
import Zettel.Types

zettelIdToLink :: ZettelId -> Inline
zettelIdToLink ident = Link mempty [Str $ "#" <> unZettelId ident] ("/" <> unZettelId ident, "")

renderZettelLinks :: [ZettelId] -> Block
renderZettelLinks =
  BulletList . map (\ident -> [Para [zettelIdToLink ident]])

toInlines :: Text -> [Inline]
toInlines t = intersperse Space . map Str $ T.words t

renderTitleLinks :: Int -> Text -> [ZettelId] -> [Block]
renderTitleLinks level title ids =
  [Header level mempty (toInlines title), renderZettelLinks ids]

renderZettel :: ZettelId -> ZettelNode -> IO Text
renderZettel _ zettel = do
  templateFile <- getDataFileName "data/markdown.template"
  template <- decodeUtf8 <$> readFileBS templateFile
  Right templ <- runIOorExplode . runWithDefaultPartials $ compileTemplate "" template
  runIOorExplode $
    writeMarkdown
      (def {writerTemplate = Just templ, writerExtensions = multimarkdownExtensions})
      (zettel.zettelNodeZettel.zettelBody)

renderZettelFile :: FilePath -> ZettelId -> ZettelNode -> IO ()
renderZettelFile dir ident zettel = do
  t <- renderZettel ident zettel
  writeFileText (dir <> "/" <> toString (unZettelId ident <> ".md")) t

renderZettelGraphFile :: FilePath -> ZettelGraph -> IO ()
renderZettelGraphFile fp zg =
  forM_ (Map.assocs (unZettelGraph zg)) $ uncurry (renderZettelFile fp)