import Lang
import Ebnf
import Spans
import Glosses

import Text.Pandoc.Definition
import Text.Pandoc.JSON
import Text.Pandoc.Walk
import qualified Data.Map as Map


main :: IO ()
main = toJSONFilter filter where
  filter p@(Pandoc (Meta m) _) = do
    lang' <- toLang $ Map.lookup "conlang" m
    let ?lang = lang'
    fmap (walk makeEbnf .
          walk (concatMap makeBlocks) .
          walk inlineLetterList) $
      walkM spans =<<
      walkM (fmap concat . traverse glosses) p


makeBlocks :: Block -> [Block]
makeBlocks (Div ("", [cls], []) blks)
  | cls `elem` ["figure", "aside"] = [open] ++ blks ++ [close]
  where
    open  = html $ "<" <> cls <> ">"
    close = html $ "</" <> cls <> ">"
    html  = RawBlock (Format "html")
makeBlocks b = [b]


inlineLetterList :: Block -> Block
inlineLetterList (Div a@(_, cs, _) blks)
  | "letter-list" `elem` cs = Div a (walk go blks)
 where
  go (Para xs) = Plain xs
  go b         = b
inlineLetterList b = b