{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE FlexibleInstances     #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE OverloadedStrings     #-}
{-# LANGUAGE PatternGuards         #-}
{-# LANGUAGE ScopedTypeVariables   #-}
{-
Copyright (C) 2006-2018 John MacFarlane <jgm@berkeley.edu>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-}

{- |
   Module      : Text.Pandoc.Readers.LaTeX
   Copyright   : Copyright (C) 2006-2018 John MacFarlane
   License     : GNU GPL, version 2 or above

   Maintainer  : John MacFarlane <jgm@berkeley.edu>
   Stability   : alpha
   Portability : portable

Conversion of LaTeX to 'Pandoc' document.

-}
module Text.Pandoc.Readers.LaTeX ( readLaTeX,
                                   applyMacros,
                                   rawLaTeXInline,
                                   rawLaTeXBlock,
                                   inlineCommand,
                                   tokenize,
                                   untokenize
                                 ) where

import Prelude
import Control.Applicative (many, optional, (<|>))
import Control.Monad
import Control.Monad.Except (throwError)
import Data.Char (isDigit, isLetter, toLower, toUpper)
import Data.Default
import Data.List (intercalate, isPrefixOf)
import qualified Data.Map as M
import Data.Maybe (fromMaybe, maybeToList)
import qualified Data.Set as Set
import Data.Text (Text)
import qualified Data.Text as T
import Safe (minimumDef)
import System.FilePath (addExtension, replaceExtension, takeExtension)
import Text.Pandoc.BCP47 (Lang (..), renderLang)
import Text.Pandoc.Builder
import Text.Pandoc.Class (PandocMonad, PandocPure, getResourcePath, lookupEnv,
                          readFileFromDirs, report, setResourcePath,
                          setTranslations, translateTerm, trace)
import Text.Pandoc.Error (PandocError ( PandocParseError, PandocParsecError))
import Text.Pandoc.Highlighting (fromListingsLanguage, languagesByExtension)
import Text.Pandoc.ImageSize (numUnit, showFl)
import Text.Pandoc.Logging
import Text.Pandoc.Options
import Text.Pandoc.Parsing hiding (blankline, many, mathDisplay, mathInline,
                            optional, space, spaces, withRaw, (<|>))
import Text.Pandoc.Readers.LaTeX.Types (ExpansionPoint (..), Macro (..),
                                        ArgSpec (..), Tok (..), TokType (..))
import Text.Pandoc.Readers.LaTeX.Parsing
import Text.Pandoc.Shared
import qualified Text.Pandoc.Translations as Translations
import Text.Pandoc.Walk
import qualified Text.Pandoc.Builder as B

-- for debugging:
-- import Text.Pandoc.Extensions (getDefaultExtensions)
-- import Text.Pandoc.Class (runIOorExplode, PandocIO)
-- import Debug.Trace (traceShowId)

-- | Parse LaTeX from string and return 'Pandoc' document.
readLaTeX :: PandocMonad m
          => ReaderOptions -- ^ Reader options
          -> Text        -- ^ String to parse (assumes @'\n'@ line endings)
          -> m Pandoc
readLaTeX opts ltx = do
  parsed <- runParserT parseLaTeX def{ sOptions = opts } "source"
               (tokenize "source" (crFilter ltx))
  case parsed of
    Right result -> return result
    Left e       -> throwError $ PandocParsecError (T.unpack ltx) e

parseLaTeX :: PandocMonad m => LP m Pandoc
parseLaTeX = do
  bs <- blocks
  eof
  st <- getState
  let meta = sMeta st
  let doc' = doc bs
  let headerLevel (Header n _ _) = [n]
      headerLevel _              = []
  let bottomLevel = minimumDef 1 $ query headerLevel doc'
  let adjustHeaders m (Header n attr ils) = Header (n+m) attr ils
      adjustHeaders _ x                   = x
  let (Pandoc _ bs') =
       -- handle the case where you have \part or \chapter
       (if bottomLevel < 1
           then walk (adjustHeaders (1 - bottomLevel))
           else id) $
       walk (resolveRefs (sLabels st)) doc'
  return $ Pandoc meta bs'

resolveRefs :: M.Map String [Inline] -> Inline -> Inline
resolveRefs labels x@(Link (ident,classes,kvs) _ _) =
  case (lookup "reference-type" kvs,
        lookup "reference" kvs) of
        (Just "ref", Just lab) ->
          case M.lookup lab labels of
               Just txt -> Link (ident,classes,kvs) txt ('#':lab, "")
               Nothing  -> x
        _ -> x
resolveRefs _ x = x


-- testParser :: LP PandocIO a -> Text -> IO a
-- testParser p t = do
--   res <- runIOorExplode (runParserT p defaultLaTeXState{
--             sOptions = def{ readerExtensions =
--               enableExtension Ext_raw_tex $
--                 getDefaultExtensions "latex" }} "source" (tokenize "source" t))
--   case res of
--        Left e  -> error (show e)
--        Right r -> return r


rawLaTeXBlock :: (PandocMonad m, HasMacros s, HasReaderOptions s)
              => ParserT String s m String
rawLaTeXBlock = do
  lookAhead (try (char '\\' >> letter))
  snd <$> (rawLaTeXParser False macroDef blocks
      <|> (rawLaTeXParser True
             (do choice (map controlSeq
                   ["include", "input", "subfile", "usepackage"])
                 skipMany opt
                 braced
                 return mempty) blocks)
      <|> rawLaTeXParser True
           (environment <|> blockCommand)
           (mconcat <$> (many (block <|> beginOrEndCommand))))

-- See #4667 for motivation; sometimes people write macros
-- that just evaluate to a begin or end command, which blockCommand
-- won't accept.
beginOrEndCommand :: PandocMonad m => LP m Blocks
beginOrEndCommand = try $ do
  Tok _ (CtrlSeq name) txt <- anyControlSeq
  guard $ name == "begin" || name == "end"
  (envname, rawargs) <- withRaw braced
  if M.member (untokenize envname)
      (inlineEnvironments :: M.Map Text (LP PandocPure Inlines))
     then mzero
     else return $ rawBlock "latex"
                    (T.unpack (txt <> untokenize rawargs))

rawLaTeXInline :: (PandocMonad m, HasMacros s, HasReaderOptions s)
               => ParserT String s m String
rawLaTeXInline = do
  lookAhead (try (char '\\' >> letter))
  snd <$> (  rawLaTeXParser True
              (mempty <$ (controlSeq "input" >> skipMany opt >> braced))
              inlines
        <|> rawLaTeXParser True (inlineEnvironment <|> inlineCommand') inlines)

inlineCommand :: PandocMonad m => ParserT String ParserState m Inlines
inlineCommand = do
  lookAhead (try (char '\\' >> letter))
  fst <$> rawLaTeXParser True (inlineEnvironment <|> inlineCommand') inlines

-- inline elements:

word :: PandocMonad m => LP m Inlines
word = (str . T.unpack . untoken) <$> satisfyTok isWordTok

regularSymbol :: PandocMonad m => LP m Inlines
regularSymbol = (str . T.unpack . untoken) <$> satisfyTok isRegularSymbol
  where isRegularSymbol (Tok _ Symbol t) = not $ T.any isSpecial t
        isRegularSymbol _                = False
        isSpecial c = c `Set.member` specialChars

inlineGroup :: PandocMonad m => LP m Inlines
inlineGroup = do
  ils <- grouped inline
  if isNull ils
     then return mempty
     else return $ spanWith nullAttr ils
          -- we need the span so we can detitlecase bibtex entries;
          -- we need to know when something is {C}apitalized

doLHSverb :: PandocMonad m => LP m Inlines
doLHSverb =
  (codeWith ("",["haskell"],[]) . T.unpack . untokenize)
    <$> manyTill (satisfyTok (not . isNewlineTok)) (symbol '|')

mkImage :: PandocMonad m => [(String, String)] -> String -> LP m Inlines
mkImage options src = do
   let replaceTextwidth (k,v) =
         case numUnit v of
              Just (num, "\\textwidth") -> (k, showFl (num * 100) ++ "%")
              _                         -> (k, v)
   let kvs = map replaceTextwidth
             $ filter (\(k,_) -> k `elem` ["width", "height"]) options
   let attr = ("",[], kvs)
   let alt = str "image"
   case takeExtension src of
        "" -> do
              defaultExt <- getOption readerDefaultImageExtension
              return $ imageWith attr (addExtension src defaultExt) "" alt
        _  -> return $ imageWith attr src "" alt

doxspace :: PandocMonad m => LP m Inlines
doxspace =
  (space <$ lookAhead (satisfyTok startsWithLetter)) <|> return mempty
  where startsWithLetter (Tok _ Word t) =
          case T.uncons t of
               Just (c, _) | isLetter c -> True
               _           -> False
        startsWithLetter _ = False


-- converts e.g. \SI{1}[\$]{} to "$ 1" or \SI{1}{\euro} to "1 €"
dosiunitx :: PandocMonad m => LP m Inlines
dosiunitx = do
  skipopts
  value <- tok
  valueprefix <- option "" $ bracketed tok
  unit <- grouped (mconcat <$> many1 siUnit) <|> siUnit <|> tok
  let emptyOr160 "" = ""
      emptyOr160 _  = "\160"
  return . mconcat $ [valueprefix,
                      emptyOr160 valueprefix,
                      value,
                      emptyOr160 unit,
                      unit]

siUnit :: PandocMonad m => LP m Inlines
siUnit = do
  Tok _ (CtrlSeq name) _ <- anyControlSeq
  if name == "square"
     then do
       unit <- grouped (mconcat <$> many1 siUnit) <|> siUnit <|> tok
       return . mconcat $ [unit, "\178"]
     else
       case M.lookup name siUnitMap of
            Just il -> return il
            Nothing -> mzero

siUnitMap :: M.Map Text Inlines
siUnitMap = M.fromList
  [ ("fg", str "fg")
  , ("pg", str "pg")
  , ("ng", str "ng")
  , ("ug", str "μg")
  , ("mg", str "mg")
  , ("g", str "g")
  , ("kg", str "kg")
  , ("amu", str "u")
  , ("pm", str "pm")
  , ("nm", str "nm")
  , ("um", str "μm")
  , ("mm", str "mm")
  , ("cm", str "cm")
  , ("dm", str "dm")
  , ("m", str "m")
  , ("km", str "km")
  , ("as", str "as")
  , ("fs", str "fs")
  , ("ps", str "ps")
  , ("ns", str "ns")
  , ("us", str "μs")
  , ("ms", str "ms")
  , ("s", str "s")
  , ("fmol", str "fmol")
  , ("pmol", str "pmol")
  , ("nmol", str "nmol")
  , ("umol", str "μmol")
  , ("mmol", str "mmol")
  , ("mol", str "mol")
  , ("kmol", str "kmol")
  , ("pA", str "pA")
  , ("nA", str "nA")
  , ("uA", str "μA")
  , ("mA", str "mA")
  , ("A", str "A")
  , ("kA", str "kA")
  , ("ul", str "μl")
  , ("ml", str "ml")
  , ("l", str "l")
  , ("hl", str "hl")
  , ("uL", str "μL")
  , ("mL", str "mL")
  , ("L", str "L")
  , ("hL", str "hL")
  , ("mHz", str "mHz")
  , ("Hz", str "Hz")
  , ("kHz", str "kHz")
  , ("MHz", str "MHz")
  , ("GHz", str "GHz")
  , ("THz", str "THz")
  , ("mN", str "mN")
  , ("N", str "N")
  , ("kN", str "kN")
  , ("MN", str "MN")
  , ("Pa", str "Pa")
  , ("kPa", str "kPa")
  , ("MPa", str "MPa")
  , ("GPa", str "GPa")
  , ("mohm", str "mΩ")
  , ("kohm", str "kΩ")
  , ("Mohm", str "MΩ")
  , ("pV", str "pV")
  , ("nV", str "nV")
  , ("uV", str "μV")
  , ("mV", str "mV")
  , ("V", str "V")
  , ("kV", str "kV")
  , ("W", str "W")
  , ("uW", str "μW")
  , ("mW", str "mW")
  , ("kW", str "kW")
  , ("MW", str "MW")
  , ("GW", str "GW")
  , ("J", str "J")
  , ("uJ", str "μJ")
  , ("mJ", str "mJ")
  , ("kJ", str "kJ")
  , ("eV", str "eV")
  , ("meV", str "meV")
  , ("keV", str "keV")
  , ("MeV", str "MeV")
  , ("GeV", str "GeV")
  , ("TeV", str "TeV")
  , ("kWh", str "kWh")
  , ("F", str "F")
  , ("fF", str "fF")
  , ("pF", str "pF")
  , ("K", str "K")
  , ("dB", str "dB")
  , ("angstrom", str "Å")
  , ("arcmin", str "′")
  , ("arcminute", str "′")
  , ("arcsecond", str "″")
  , ("astronomicalunit", str "ua")
  , ("atomicmassunit", str "u")
  , ("atto", str "a")
  , ("bar", str "bar")
  , ("barn", str "b")
  , ("becquerel", str "Bq")
  , ("bel", str "B")
  , ("candela", str "cd")
  , ("celsius", str "°C")
  , ("centi", str "c")
  , ("coulomb", str "C")
  , ("dalton", str "Da")
  , ("day", str "d")
  , ("deca", str "d")
  , ("deci", str "d")
  , ("decibel", str "db")
  , ("degreeCelsius",str "°C")
  , ("degree", str "°")
  , ("deka", str "d")
  , ("electronvolt", str "eV")
  , ("exa", str "E")
  , ("farad", str "F")
  , ("femto", str "f")
  , ("giga", str "G")
  , ("gram", str "g")
  , ("hectare", str "ha")
  , ("hecto", str "h")
  , ("henry", str "H")
  , ("hertz", str "Hz")
  , ("hour", str "h")
  , ("joule", str "J")
  , ("katal", str "kat")
  , ("kelvin", str "K")
  , ("kilo", str "k")
  , ("kilogram", str "kg")
  , ("knot", str "kn")
  , ("liter", str "L")
  , ("litre", str "l")
  , ("lumen", str "lm")
  , ("lux", str "lx")
  , ("mega", str "M")
  , ("meter", str "m")
  , ("metre", str "m")
  , ("milli", str "m")
  , ("minute", str "min")
  , ("mmHg", str "mmHg")
  , ("mole", str "mol")
  , ("nano", str "n")
  , ("nauticalmile", str "M")
  , ("neper", str "Np")
  , ("newton", str "N")
  , ("ohm", str "Ω")
  , ("Pa", str "Pa")
  , ("pascal", str "Pa")
  , ("percent", str "%")
  , ("per", str "/")
  , ("peta", str "P")
  , ("pico", str "p")
  , ("radian", str "rad")
  , ("second", str "s")
  , ("siemens", str "S")
  , ("sievert", str "Sv")
  , ("steradian", str "sr")
  , ("tera", str "T")
  , ("tesla", str "T")
  , ("tonne", str "t")
  , ("volt", str "V")
  , ("watt", str "W")
  , ("weber", str "Wb")
  , ("yocto", str "y")
  , ("yotta", str "Y")
  , ("zepto", str "z")
  , ("zetta", str "Z")
  ]

lit :: String -> LP m Inlines
lit = pure . str

removeDoubleQuotes :: Text -> Text
removeDoubleQuotes t =
  Data.Maybe.fromMaybe t $ T.stripPrefix "\"" t >>= T.stripSuffix "\""

doubleQuote :: PandocMonad m => LP m Inlines
doubleQuote =
       quoted' doubleQuoted (try $ count 2 $ symbol '`')
                     (void $ try $ count 2 $ symbol '\'')
   <|> quoted' doubleQuoted ((:[]) <$> symbol '“') (void $ symbol '”')
   -- the following is used by babel for localized quotes:
   <|> quoted' doubleQuoted (try $ sequence [symbol '"', symbol '`'])
                            (void $ try $ sequence [symbol '"', symbol '\''])

singleQuote :: PandocMonad m => LP m Inlines
singleQuote =
       quoted' singleQuoted ((:[]) <$> symbol '`')
                     (try $ symbol '\'' >>
                           notFollowedBy (satisfyTok startsWithLetter))
   <|> quoted' singleQuoted ((:[]) <$> symbol '‘')
                            (try $ symbol '’' >>
                                  notFollowedBy (satisfyTok startsWithLetter))
  where startsWithLetter (Tok _ Word t) =
          case T.uncons t of
               Just (c, _) | isLetter c -> True
               _           -> False
        startsWithLetter _ = False

quoted' :: PandocMonad m
        => (Inlines -> Inlines)
        -> LP m [Tok]
        -> LP m ()
        -> LP m Inlines
quoted' f starter ender = do
  startchs <- (T.unpack . untokenize) <$> starter
  smart <- extensionEnabled Ext_smart <$> getOption readerExtensions
  if smart
     then do
       ils <- many (notFollowedBy ender >> inline)
       (ender >> return (f (mconcat ils))) <|>
            (<> mconcat ils) <$>
                    lit (case startchs of
                              "``" -> "“"
                              "`"  -> "‘"
                              cs   -> cs)
     else lit startchs

enquote :: PandocMonad m => Bool -> Maybe Text -> LP m Inlines
enquote starred mblang = do
  skipopts
  let lang = (T.unpack <$> mblang) >>= babelLangToBCP47
  let langspan = case lang of
                      Nothing -> id
                      Just l  -> spanWith ("",[],[("lang", renderLang l)])
  quoteContext <- sQuoteContext <$> getState
  if starred || quoteContext == InDoubleQuote
     then singleQuoted . langspan <$> withQuoteContext InSingleQuote tok
     else doubleQuoted . langspan <$> withQuoteContext InDoubleQuote tok

blockquote :: PandocMonad m => Bool -> Maybe Text -> LP m Blocks
blockquote citations mblang = do
  citePar <- if citations
                then do
                  cs <- cites NormalCitation False
                  return $ para (cite cs mempty)
                else return mempty
  let lang = (T.unpack <$> mblang) >>= babelLangToBCP47
  let langdiv = case lang of
                      Nothing -> id
                      Just l  -> divWith ("",[],[("lang", renderLang l)])
  bs <- grouped block
  return $ blockQuote . langdiv $ (bs <> citePar)

doAcronym :: PandocMonad m => String -> LP m Inlines
doAcronym form = do
  acro <- braced
  return . mconcat $ [spanWith ("",[],[("acronym-label", toksToString acro),
    ("acronym-form", "singular+" ++ form)])
    $ str $ toksToString acro]

doAcronymPlural :: PandocMonad m => String -> LP m Inlines
doAcronymPlural form = do
  acro <- braced
  plural <- lit "s"
  return . mconcat $ [spanWith ("",[],[("acronym-label", toksToString acro),
    ("acronym-form", "plural+" ++ form)]) $
   mconcat [str $ toksToString acro, plural]]

doverb :: PandocMonad m => LP m Inlines
doverb = do
  Tok _ Symbol t <- anySymbol
  marker <- case T.uncons t of
              Just (c, ts) | T.null ts -> return c
              _            -> mzero
  withVerbatimMode $
    (code . T.unpack . untokenize) <$>
      manyTill (verbTok marker) (symbol marker)

verbTok :: PandocMonad m => Char -> LP m Tok
verbTok stopchar = do
  t@(Tok pos toktype txt) <- satisfyTok (not . isNewlineTok)
  case T.findIndex (== stopchar) txt of
       Nothing -> return t
       Just i  -> do
         let (t1, t2) = T.splitAt i txt
         inp <- getInput
         setInput $ Tok (incSourceColumn pos i) Symbol (T.singleton stopchar)
                  : totoks (incSourceColumn pos (i + 1)) (T.drop 1 t2) ++ inp
         return $ Tok pos toktype t1

dolstinline :: PandocMonad m => LP m Inlines
dolstinline = do
  options <- option [] keyvals
  let classes = maybeToList $ lookup "language" options >>= fromListingsLanguage
  doinlinecode classes

domintinline :: PandocMonad m => LP m Inlines
domintinline = do
  skipopts
  cls <- toksToString <$> braced
  doinlinecode [cls]

doinlinecode :: PandocMonad m => [String] -> LP m Inlines
doinlinecode classes = do
  Tok _ Symbol t <- anySymbol
  marker <- case T.uncons t of
              Just (c, ts) | T.null ts -> return c
              _            -> mzero
  let stopchar = if marker == '{' then '}' else marker
  withVerbatimMode $
    (codeWith ("",classes,[]) . T.unpack . untokenize) <$>
      manyTill (verbTok stopchar) (symbol stopchar)

keyval :: PandocMonad m => LP m (String, String)
keyval = try $ do
  Tok _ Word key <- satisfyTok isWordTok
  optional sp
  val <- option mempty $ do
           symbol '='
           optional sp
           (untokenize <$> braced) <|>
             (mconcat <$> many1 (
                 (untokenize . snd <$> withRaw braced)
                 <|>
                 (untokenize <$> (many1
                      (satisfyTok
                         (\t -> case t of
                                Tok _ Symbol "]" -> False
                                Tok _ Symbol "," -> False
                                Tok _ Symbol "{" -> False
                                Tok _ Symbol "}" -> False
                                _                -> True))))))
  optional (symbol ',')
  optional sp
  return (T.unpack key, T.unpack $ T.strip val)

keyvals :: PandocMonad m => LP m [(String, String)]
keyvals = try $ symbol '[' >> manyTill keyval (symbol ']')

accent :: PandocMonad m => Char -> (Char -> String) -> LP m Inlines
accent c f = try $ do
  ils <- tok
  case toList ils of
       (Str (x:xs) : ys) -> return $ fromList $
         case f x of
              [z] | z == x -> Str ([z,c] ++ xs) : ys -- combining accent
              zs           -> Str (zs ++ xs) : ys
       [Space]           -> return $ str [c]
       []                -> return $ str [c]
       _                 -> return ils

grave :: Char -> String
grave 'A' = "À"
grave 'E' = "È"
grave 'I' = "Ì"
grave 'O' = "Ò"
grave 'U' = "Ù"
grave 'a' = "à"
grave 'e' = "è"
grave 'i' = "ì"
grave 'o' = "ò"
grave 'u' = "ù"
grave c   = [c]

acute :: Char -> String
acute 'A' = "Á"
acute 'E' = "É"
acute 'I' = "Í"
acute 'O' = "Ó"
acute 'U' = "Ú"
acute 'Y' = "Ý"
acute 'a' = "á"
acute 'e' = "é"
acute 'i' = "í"
acute 'o' = "ó"
acute 'u' = "ú"
acute 'y' = "ý"
acute 'C' = "Ć"
acute 'c' = "ć"
acute 'L' = "Ĺ"
acute 'l' = "ĺ"
acute 'N' = "Ń"
acute 'n' = "ń"
acute 'R' = "Ŕ"
acute 'r' = "ŕ"
acute 'S' = "Ś"
acute 's' = "ś"
acute 'Z' = "Ź"
acute 'z' = "ź"
acute c   = [c]

circ :: Char -> String
circ 'A' = "Â"
circ 'E' = "Ê"
circ 'I' = "Î"
circ 'O' = "Ô"
circ 'U' = "Û"
circ 'a' = "â"
circ 'e' = "ê"
circ 'i' = "î"
circ 'o' = "ô"
circ 'u' = "û"
circ 'C' = "Ĉ"
circ 'c' = "ĉ"
circ 'G' = "Ĝ"
circ 'g' = "ĝ"
circ 'H' = "Ĥ"
circ 'h' = "ĥ"
circ 'J' = "Ĵ"
circ 'j' = "ĵ"
circ 'S' = "Ŝ"
circ 's' = "ŝ"
circ 'W' = "Ŵ"
circ 'w' = "ŵ"
circ 'Y' = "Ŷ"
circ 'y' = "ŷ"
circ c   = [c]

tilde :: Char -> String
tilde 'A' = "Ã"
tilde 'a' = "ã"
tilde 'O' = "Õ"
tilde 'o' = "õ"
tilde 'I' = "Ĩ"
tilde 'i' = "ĩ"
tilde 'U' = "Ũ"
tilde 'u' = "ũ"
tilde 'N' = "Ñ"
tilde 'n' = "ñ"
tilde c   = [c]

umlaut :: Char -> String
umlaut 'A' = "Ä"
umlaut 'E' = "Ë"
umlaut 'I' = "Ï"
umlaut 'O' = "Ö"
umlaut 'U' = "Ü"
umlaut 'a' = "ä"
umlaut 'e' = "ë"
umlaut 'i' = "ï"
umlaut 'o' = "ö"
umlaut 'u' = "ü"
umlaut c   = [c]

hungarumlaut :: Char -> String
hungarumlaut 'A' = "A̋"
hungarumlaut 'E' = "E̋"
hungarumlaut 'I' = "I̋"
hungarumlaut 'O' = "Ő"
hungarumlaut 'U' = "Ű"
hungarumlaut 'Y' = "ӳ"
hungarumlaut 'a' = "a̋"
hungarumlaut 'e' = "e̋"
hungarumlaut 'i' = "i̋"
hungarumlaut 'o' = "ő"
hungarumlaut 'u' = "ű"
hungarumlaut 'y' = "ӳ"
hungarumlaut c   = [c]

dot :: Char -> String
dot 'C' = "Ċ"
dot 'c' = "ċ"
dot 'E' = "Ė"
dot 'e' = "ė"
dot 'G' = "Ġ"
dot 'g' = "ġ"
dot 'I' = "İ"
dot 'Z' = "Ż"
dot 'z' = "ż"
dot c   = [c]

macron :: Char -> String
macron 'A' = "Ā"
macron 'E' = "Ē"
macron 'I' = "Ī"
macron 'O' = "Ō"
macron 'U' = "Ū"
macron 'a' = "ā"
macron 'e' = "ē"
macron 'i' = "ī"
macron 'o' = "ō"
macron 'u' = "ū"
macron c   = [c]

ringabove :: Char -> String
ringabove 'A' = "Å"
ringabove 'a' = "å"
ringabove 'U' = "Ů"
ringabove 'u' = "ů"
ringabove c   = [c]

dotbelow :: Char -> String
dotbelow 'B' = "Ḅ"
dotbelow 'b' = "ḅ"
dotbelow 'D' = "Ḍ"
dotbelow 'd' = "ḍ"
dotbelow 'H' = "Ḥ"
dotbelow 'h' = "ḥ"
dotbelow 'K' = "Ḳ"
dotbelow 'k' = "ḳ"
dotbelow 'L' = "Ḷ"
dotbelow 'l' = "ḷ"
dotbelow 'M' = "Ṃ"
dotbelow 'm' = "ṃ"
dotbelow 'N' = "Ṇ"
dotbelow 'n' = "ṇ"
dotbelow 'R' = "Ṛ"
dotbelow 'r' = "ṛ"
dotbelow 'S' = "Ṣ"
dotbelow 's' = "ṣ"
dotbelow 'T' = "Ṭ"
dotbelow 't' = "ṭ"
dotbelow 'V' = "Ṿ"
dotbelow 'v' = "ṿ"
dotbelow 'W' = "Ẉ"
dotbelow 'w' = "ẉ"
dotbelow 'Z' = "Ẓ"
dotbelow 'z' = "ẓ"
dotbelow 'A' = "Ạ"
dotbelow 'a' = "ạ"
dotbelow 'E' = "Ẹ"
dotbelow 'e' = "ẹ"
dotbelow 'I' = "Ị"
dotbelow 'i' = "ị"
dotbelow 'O' = "Ọ"
dotbelow 'o' = "ọ"
dotbelow 'U' = "Ụ"
dotbelow 'u' = "ụ"
dotbelow 'Y' = "Ỵ"
dotbelow 'y' = "ỵ"
dotbelow c   = [c]

doublegrave :: Char -> String
doublegrave 'A' = "Ȁ"
doublegrave 'a' = "ȁ"
doublegrave 'E' = "Ȅ"
doublegrave 'e' = "ȅ"
doublegrave 'I' = "Ȉ"
doublegrave 'i' = "ȉ"
doublegrave 'O' = "Ȍ"
doublegrave 'o' = "ȍ"
doublegrave 'R' = "Ȑ"
doublegrave 'r' = "ȑ"
doublegrave 'U' = "Ȕ"
doublegrave 'u' = "ȕ"
doublegrave c   = [c]

hookabove :: Char -> String
hookabove 'A' = "Ả"
hookabove 'a' = "ả"
hookabove 'E' = "Ẻ"
hookabove 'e' = "ẻ"
hookabove 'I' = "Ỉ"
hookabove 'i' = "ỉ"
hookabove 'O' = "Ỏ"
hookabove 'o' = "ỏ"
hookabove 'U' = "Ủ"
hookabove 'u' = "ủ"
hookabove 'Y' = "Ỷ"
hookabove 'y' = "ỷ"
hookabove c   = [c]

cedilla :: Char -> String
cedilla 'c' = "ç"
cedilla 'C' = "Ç"
cedilla 's' = "ş"
cedilla 'S' = "Ş"
cedilla 't' = "ţ"
cedilla 'T' = "Ţ"
cedilla 'e' = "ȩ"
cedilla 'E' = "Ȩ"
cedilla 'h' = "ḩ"
cedilla 'H' = "Ḩ"
cedilla 'o' = "o̧"
cedilla 'O' = "O̧"
cedilla c   = [c]

hacek :: Char -> String
hacek 'A' = "Ǎ"
hacek 'a' = "ǎ"
hacek 'C' = "Č"
hacek 'c' = "č"
hacek 'D' = "Ď"
hacek 'd' = "ď"
hacek 'E' = "Ě"
hacek 'e' = "ě"
hacek 'G' = "Ǧ"
hacek 'g' = "ǧ"
hacek 'H' = "Ȟ"
hacek 'h' = "ȟ"
hacek 'I' = "Ǐ"
hacek 'i' = "ǐ"
hacek 'j' = "ǰ"
hacek 'K' = "Ǩ"
hacek 'k' = "ǩ"
hacek 'L' = "Ľ"
hacek 'l' = "ľ"
hacek 'N' = "Ň"
hacek 'n' = "ň"
hacek 'O' = "Ǒ"
hacek 'o' = "ǒ"
hacek 'R' = "Ř"
hacek 'r' = "ř"
hacek 'S' = "Š"
hacek 's' = "š"
hacek 'T' = "Ť"
hacek 't' = "ť"
hacek 'U' = "Ǔ"
hacek 'u' = "ǔ"
hacek 'Z' = "Ž"
hacek 'z' = "ž"
hacek c   = [c]

ogonek :: Char -> String
ogonek 'a' = "ą"
ogonek 'e' = "ę"
ogonek 'o' = "ǫ"
ogonek 'i' = "į"
ogonek 'u' = "ų"
ogonek 'A' = "Ą"
ogonek 'E' = "Ę"
ogonek 'I' = "Į"
ogonek 'O' = "Ǫ"
ogonek 'U' = "Ų"
ogonek c   = [c]

breve :: Char -> String
breve 'A' = "Ă"
breve 'a' = "ă"
breve 'E' = "Ĕ"
breve 'e' = "ĕ"
breve 'G' = "Ğ"
breve 'g' = "ğ"
breve 'I' = "Ĭ"
breve 'i' = "ĭ"
breve 'O' = "Ŏ"
breve 'o' = "ŏ"
breve 'U' = "Ŭ"
breve 'u' = "ŭ"
breve c   = [c]

mathDisplay :: String -> Inlines
mathDisplay = displayMath . trim

mathInline :: String -> Inlines
mathInline = math . trim

dollarsMath :: PandocMonad m => LP m Inlines
dollarsMath = do
  symbol '$'
  display <- option False (True <$ symbol '$')
  (do contents <- try $ T.unpack <$> pDollarsMath 0
      if display
         then (mathDisplay contents <$ symbol '$')
         else return $ mathInline contents)
   <|> (guard display >> return (mathInline ""))

-- Int is number of embedded groupings
pDollarsMath :: PandocMonad m => Int -> LP m Text
pDollarsMath n = do
  Tok _ toktype t <- anyTok
  case toktype of
       Symbol | t == "$"
              , n == 0 -> return mempty
              | t == "\\" -> do
                  Tok _ _ t' <- anyTok
                  return (t <> t')
              | t == "{" -> (t <>) <$> pDollarsMath (n+1)
              | t == "}" ->
                if n > 0
                then (t <>) <$> pDollarsMath (n-1)
                else mzero
       _ -> (t <>) <$> pDollarsMath n

-- citations

addPrefix :: [Inline] -> [Citation] -> [Citation]
addPrefix p (k:ks) = k {citationPrefix = p ++ citationPrefix k} : ks
addPrefix _ _      = []

addSuffix :: [Inline] -> [Citation] -> [Citation]
addSuffix s ks@(_:_) =
  let k = last ks
  in  init ks ++ [k {citationSuffix = citationSuffix k ++ s}]
addSuffix _ _ = []

simpleCiteArgs :: PandocMonad m => LP m [Citation]
simpleCiteArgs = try $ do
  first  <- optionMaybe $ toList <$> opt
  second <- optionMaybe $ toList <$> opt
  keys <- try $ bgroup *> manyTill citationLabel egroup
  let (pre, suf) = case (first  , second ) of
        (Just s , Nothing) -> (mempty, s )
        (Just s , Just t ) -> (s , t )
        _                  -> (mempty, mempty)
      conv k = Citation { citationId      = k
                        , citationPrefix  = []
                        , citationSuffix  = []
                        , citationMode    = NormalCitation
                        , citationHash    = 0
                        , citationNoteNum = 0
                        }
  return $ addPrefix pre $ addSuffix suf $ map conv keys

citationLabel :: PandocMonad m => LP m String
citationLabel  = do
  optional spaces
  toksToString <$>
    (many1 (satisfyTok isWordTok <|> symbolIn bibtexKeyChar)
          <* optional spaces
          <* optional (symbol ',')
          <* optional spaces)
  where bibtexKeyChar = ".:;?!`'()/*@_+=-[]" :: [Char]

cites :: PandocMonad m => CitationMode -> Bool -> LP m [Citation]
cites mode multi = try $ do
  cits <- if multi
             then do
               multiprenote <- optionMaybe $ toList <$> paropt
               multipostnote <- optionMaybe $ toList <$> paropt
               let (pre, suf) = case (multiprenote, multipostnote) of
                     (Just s , Nothing) -> (mempty, s)
                     (Nothing , Just t) -> (mempty, t)
                     (Just s , Just t ) -> (s, t)
                     _                  -> (mempty, mempty)
               tempCits <- many1 simpleCiteArgs
               case tempCits of
                 (k:ks) -> case ks of
                             (_:_) -> return $ ((addMprenote pre k):init ks) ++
                                                 [addMpostnote suf (last ks)]
                             _ -> return [addMprenote pre (addMpostnote suf k)]
                 _ -> return [[]]
             else count 1 simpleCiteArgs
  let cs = concat cits
  return $ case mode of
        AuthorInText -> case cs of
                             (c:rest) -> c {citationMode = mode} : rest
                             []       -> []
        _            -> map (\a -> a {citationMode = mode}) cs
  where mprenote (k:ks) = (k:ks) ++ [Space]
        mprenote _ = mempty
        mpostnote (k:ks) = [Str ",", Space] ++ (k:ks)
        mpostnote _ = mempty
        addMprenote mpn (k:ks) =
          let mpnfinal = case citationPrefix k of
                           (_:_) -> mprenote mpn
                           _ -> mpn
          in addPrefix mpnfinal (k:ks)
        addMprenote _ _ = []
        addMpostnote = addSuffix . mpostnote

citation :: PandocMonad m => String -> CitationMode -> Bool -> LP m Inlines
citation name mode multi = do
  (c,raw) <- withRaw $ cites mode multi
  return $ cite c (rawInline "latex" $ "\\" ++ name ++ toksToString raw)

handleCitationPart :: Inlines -> [Citation]
handleCitationPart ils =
  let isCite Cite{} = True
      isCite _      = False
      (pref, rest) = break isCite (toList ils)
  in case rest of
          (Cite cs _:suff) -> addPrefix pref $ addSuffix suff cs
          _                -> []

complexNatbibCitation :: PandocMonad m => CitationMode -> LP m Inlines
complexNatbibCitation mode = try $ do
  (cs, raw) <-
    withRaw $ concat <$> do
      bgroup
      items <- mconcat <$>
                many1 (notFollowedBy (symbol ';') >> inline)
                  `sepBy1` (symbol ';')
      egroup
      return $ map handleCitationPart items
  case cs of
       []       -> mzero
       (c:cits) -> return $ cite (c{ citationMode = mode }:cits)
                      (rawInline "latex" $ "\\citetext" ++ toksToString raw)

inNote :: Inlines -> Inlines
inNote ils =
  note $ para $ ils <> str "."

inlineCommand' :: PandocMonad m => LP m Inlines
inlineCommand' = try $ do
  Tok _ (CtrlSeq name) cmd <- anyControlSeq
  guard $ name /= "begin" && name /= "end"
  star <- option "" ("*" <$ symbol '*' <* optional sp)
  let name' = name <> star
  let names = ordNub [name', name] -- check non-starred as fallback
  let raw = do
       guard $ isInlineCommand name || not (isBlockCommand name)
       rawcommand <- getRawCommand name (cmd <> star)
       (guardEnabled Ext_raw_tex >> return (rawInline "latex" rawcommand))
         <|> ignore rawcommand
  lookupListDefault raw names inlineCommands

tok :: PandocMonad m => LP m Inlines
tok = try $ spaces >> grouped inline <|> inlineCommand' <|> singleChar'
  where singleChar' = do
          Tok _ _ t <- singleChar
          return (str (T.unpack t))

opt :: PandocMonad m => LP m Inlines
opt = bracketed inline <|> (str . T.unpack <$> rawopt)

paropt :: PandocMonad m => LP m Inlines
paropt = parenWrapped inline

rawopt :: PandocMonad m => LP m Text
rawopt = do
  inner <- untokenize <$> bracketedToks
  optional sp
  return $ "[" <> inner <> "]"

skipopts :: PandocMonad m => LP m ()
skipopts = skipMany (overlaySpecification <|> void rawopt)

-- opts in angle brackets are used in beamer
overlaySpecification :: PandocMonad m => LP m ()
overlaySpecification = try $ do
  symbol '<'
  ts <- manyTill overlayTok (symbol '>')
  guard $ case ts of
               -- see issue #3368
               [Tok _ Word s] | T.all isLetter s -> s `elem`
                                ["beamer","presentation", "trans",
                                 "handout","article", "second"]
               _ -> True

overlayTok :: PandocMonad m => LP m Tok
overlayTok =
  satisfyTok (\t ->
                  case t of
                    Tok _ Word _       -> True
                    Tok _ Spaces _     -> True
                    Tok _ Symbol c     -> c `elem` ["-","+","@","|",":",","]
                    _                  -> False)

inBrackets :: Inlines -> Inlines
inBrackets x = str "[" <> x <> str "]"

unescapeURL :: String -> String
unescapeURL ('\\':x:xs) | isEscapable x = x:unescapeURL xs
  where isEscapable c = c `elem` ("#$%&~_^\\{}" :: String)
unescapeURL (x:xs) = x:unescapeURL xs
unescapeURL [] = ""

mathEnvWith :: PandocMonad m
            => (Inlines -> a) -> Maybe Text -> Text -> LP m a
mathEnvWith f innerEnv name = f . mathDisplay . inner <$> mathEnv name
   where inner x = case innerEnv of
                        Nothing -> x
                        Just y  -> "\\begin{" ++ T.unpack y ++ "}\n" ++ x ++
                                   "\\end{" ++ T.unpack y ++ "}"

mathEnv :: PandocMonad m => Text -> LP m String
mathEnv name = do
  skipopts
  optional blankline
  res <- manyTill anyTok (end_ name)
  return $ stripTrailingNewlines $ T.unpack $ untokenize res

inlineEnvironment :: PandocMonad m => LP m Inlines
inlineEnvironment = try $ do
  controlSeq "begin"
  name <- untokenize <$> braced
  M.findWithDefault mzero name inlineEnvironments

inlineEnvironments :: PandocMonad m => M.Map Text (LP m Inlines)
inlineEnvironments = M.fromList [
    ("displaymath", mathEnvWith id Nothing "displaymath")
  , ("math", math <$> mathEnv "math")
  , ("equation", mathEnvWith id Nothing "equation")
  , ("equation*", mathEnvWith id Nothing "equation*")
  , ("gather", mathEnvWith id (Just "gathered") "gather")
  , ("gather*", mathEnvWith id (Just "gathered") "gather*")
  , ("multline", mathEnvWith id (Just "gathered") "multline")
  , ("multline*", mathEnvWith id (Just "gathered") "multline*")
  , ("eqnarray", mathEnvWith id (Just "aligned") "eqnarray")
  , ("eqnarray*", mathEnvWith id (Just "aligned") "eqnarray*")
  , ("align", mathEnvWith id (Just "aligned") "align")
  , ("align*", mathEnvWith id (Just "aligned") "align*")
  , ("alignat", mathEnvWith id (Just "aligned") "alignat")
  , ("alignat*", mathEnvWith id (Just "aligned") "alignat*")
  , ("dmath", mathEnvWith id Nothing "dmath")
  , ("dmath*", mathEnvWith id Nothing "dmath*")
  , ("dgroup", mathEnvWith id (Just "aligned") "dgroup")
  , ("dgroup*", mathEnvWith id (Just "aligned") "dgroup*")
  , ("darray", mathEnvWith id (Just "aligned") "darray")
  , ("darray*", mathEnvWith id (Just "aligned") "darray*")
  ]

inlineCommands :: PandocMonad m => M.Map Text (LP m Inlines)
inlineCommands = M.union inlineLanguageCommands $ M.fromList
  [ ("emph", extractSpaces emph <$> tok)
  , ("textit", extractSpaces emph <$> tok)
  , ("textsl", extractSpaces emph <$> tok)
  , ("textsc", extractSpaces smallcaps <$> tok)
  , ("textsf", extractSpaces (spanWith ("",["sans-serif"],[])) <$> tok)
  , ("textmd", extractSpaces (spanWith ("",["medium"],[])) <$> tok)
  , ("textrm", extractSpaces (spanWith ("",["roman"],[])) <$> tok)
  , ("textup", extractSpaces (spanWith ("",["upright"],[])) <$> tok)
  , ("texttt", ttfamily)
  , ("sout", extractSpaces strikeout <$> tok)
  , ("alert", skipopts >> spanWith ("",["alert"],[]) <$> tok) -- beamer
  , ("lq", return (str "‘"))
  , ("rq", return (str "’"))
  , ("textquoteleft", return (str "‘"))
  , ("textquoteright", return (str "’"))
  , ("textquotedblleft", return (str "“"))
  , ("textquotedblright", return (str "”"))
  , ("textsuperscript", extractSpaces superscript <$> tok)
  , ("textsubscript", extractSpaces subscript <$> tok)
  , ("textbackslash", lit "\\")
  , ("backslash", lit "\\")
  , ("slash", lit "/")
  , ("textbf", extractSpaces strong <$> tok)
  , ("textnormal", extractSpaces (spanWith ("",["nodecor"],[])) <$> tok)
  , ("ldots", lit "…")
  , ("vdots", lit "\8942")
  , ("dots", lit "…")
  , ("mdots", lit "…")
  , ("sim", lit "~")
  , ("sep", lit ",")
  , ("label", rawInlineOr "label" dolabel)
  , ("ref", rawInlineOr "ref" $ doref "ref")
  , ("cref", rawInlineOr "cref" $ doref "ref")       -- from cleveref.sty
  , ("vref", rawInlineOr "vref" $ doref "ref+page")  -- from varioref.sty
  , ("eqref", rawInlineOr "eqref" $ doref "eqref")   -- from amsmath.sty
  , ("lettrine", optional opt >> extractSpaces (spanWith ("",["lettrine"],[])) <$> tok)
  , ("(", mathInline . toksToString <$> manyTill anyTok (controlSeq ")"))
  , ("[", mathDisplay . toksToString <$> manyTill anyTok (controlSeq "]"))
  , ("ensuremath", mathInline . toksToString <$> braced)
  , ("texorpdfstring", (\x _ -> x) <$> tok <*> tok)
  , ("P", lit "¶")
  , ("S", lit "§")
  , ("$", lit "$")
  , ("%", lit "%")
  , ("&", lit "&")
  , ("#", lit "#")
  , ("_", lit "_")
  , ("{", lit "{")
  , ("}", lit "}")
  -- old TeX commands
  , ("em", extractSpaces emph <$> inlines)
  , ("it", extractSpaces emph <$> inlines)
  , ("sl", extractSpaces emph <$> inlines)
  , ("bf", extractSpaces strong <$> inlines)
  , ("rm", inlines)
  , ("itshape", extractSpaces emph <$> inlines)
  , ("slshape", extractSpaces emph <$> inlines)
  , ("scshape", extractSpaces smallcaps <$> inlines)
  , ("bfseries", extractSpaces strong <$> inlines)
  , ("MakeUppercase", makeUppercase <$> tok)
  , ("MakeTextUppercase", makeUppercase <$> tok) -- textcase
  , ("uppercase", makeUppercase <$> tok)
  , ("MakeLowercase", makeLowercase <$> tok)
  , ("MakeTextLowercase", makeLowercase <$> tok)
  , ("lowercase", makeLowercase <$> tok)
  , ("/", pure mempty) -- italic correction
  , ("aa", lit "å")
  , ("AA", lit "Å")
  , ("ss", lit "ß")
  , ("o", lit "ø")
  , ("O", lit "Ø")
  , ("L", lit "Ł")
  , ("l", lit "ł")
  , ("ae", lit "æ")
  , ("AE", lit "Æ")
  , ("oe", lit "œ")
  , ("OE", lit "Œ")
  , ("pounds", lit "£")
  , ("euro", lit "€")
  , ("copyright", lit "©")
  , ("textasciicircum", lit "^")
  , ("textasciitilde", lit "~")
  , ("H", accent '\779' hungarumlaut)
  , ("`", accent '`' grave)
  , ("'", accent '\'' acute)
  , ("^", accent '^' circ)
  , ("~", accent '~' tilde)
  , ("\"", accent '\776' umlaut)
  , (".", accent '\775' dot)
  , ("=", accent '\772' macron)
  , ("|", accent '\781' (:[]))  -- vertical line above
  , ("b", accent '\817' (:[]))  -- macron below
  , ("c", accent '\807' cedilla)
  , ("G", accent '\783' doublegrave)
  , ("h", accent '\777' hookabove)
  , ("d", accent '\803' dotbelow)
  , ("f", accent '\785' (:[]))  -- inverted breve
  , ("r", accent '\778' ringabove)
  , ("t", accent '\865' (:[]))  -- double inverted breve
  , ("U", accent '\782' (:[]))  -- double vertical line above
  , ("v", accent 'ˇ' hacek)
  , ("u", accent '\774' breve)
  , ("k", accent '\808' ogonek)
  , ("textogonekcentered", accent '\808' ogonek)
  , ("i", lit "ı")  -- dotless i
  , ("j", lit "ȷ")  -- dotless j
  , ("newtie", accent '\785' (:[])) -- inverted breve
  , ("textcircled", accent '\8413' (:[])) -- combining circle
  , ("\\", linebreak <$ (do inTableCell <- sInTableCell <$> getState
                            guard $ not inTableCell
                            optional opt
                            spaces))
  , (",", lit "\8198")
  , ("@", pure mempty)
  , (" ", lit "\160")
  , ("ps", pure $ str "PS." <> space)
  , ("TeX", lit "TeX")
  , ("LaTeX", lit "LaTeX")
  , ("bar", lit "|")
  , ("textless", lit "<")
  , ("textgreater", lit ">")
  , ("thanks", skipopts >> note <$> grouped block)
  , ("footnote", skipopts >> note <$> grouped block)
  , ("verb", doverb)
  , ("lstinline", dolstinline)
  , ("mintinline", domintinline)
  , ("Verb", doverb)
  , ("url", ((unescapeURL . T.unpack . untokenize) <$> bracedUrl) >>= \url ->
                  pure (link url "" (str url)))
  , ("href", (unescapeURL . toksToString <$>
                 bracedUrl <* optional sp) >>= \url ->
                   tok >>= \lab -> pure (link url "" lab))
  , ("includegraphics", do options <- option [] keyvals
                           src <- unescapeURL . T.unpack .
                                    removeDoubleQuotes . untokenize <$> braced
                           mkImage options src)
  , ("enquote*", enquote True Nothing)
  , ("enquote", enquote False Nothing)
  -- foreignquote is supposed to use native quote marks
  , ("foreignquote*", braced >>= enquote True . Just . untokenize)
  , ("foreignquote", braced >>= enquote False . Just . untokenize)
  -- hypehnquote uses regular quotes
  , ("hyphenquote*", braced >>= enquote True . Just . untokenize)
  , ("hyphenquote", braced >>= enquote False . Just . untokenize)
  , ("figurename", doTerm Translations.Figure)
  , ("prefacename", doTerm Translations.Preface)
  , ("refname", doTerm Translations.References)
  , ("bibname", doTerm Translations.Bibliography)
  , ("chaptername", doTerm Translations.Chapter)
  , ("partname", doTerm Translations.Part)
  , ("contentsname", doTerm Translations.Contents)
  , ("listfigurename", doTerm Translations.ListOfFigures)
  , ("listtablename", doTerm Translations.ListOfTables)
  , ("indexname", doTerm Translations.Index)
  , ("abstractname", doTerm Translations.Abstract)
  , ("tablename", doTerm Translations.Table)
  , ("enclname", doTerm Translations.Encl)
  , ("ccname", doTerm Translations.Cc)
  , ("headtoname", doTerm Translations.To)
  , ("pagename", doTerm Translations.Page)
  , ("seename", doTerm Translations.See)
  , ("seealsoname", doTerm Translations.SeeAlso)
  , ("proofname", doTerm Translations.Proof)
  , ("glossaryname", doTerm Translations.Glossary)
  , ("lstlistingname", doTerm Translations.Listing)
  , ("cite", citation "cite" NormalCitation False)
  , ("Cite", citation "Cite" NormalCitation False)
  , ("citep", citation "citep" NormalCitation False)
  , ("citep*", citation "citep*" NormalCitation False)
  , ("citeal", citation "citeal" NormalCitation False)
  , ("citealp", citation "citealp" NormalCitation False)
  , ("citealp*", citation "citealp*" NormalCitation False)
  , ("autocite", citation "autocite" NormalCitation False)
  , ("smartcite", citation "smartcite" NormalCitation False)
  , ("footcite", inNote <$> citation "footcite" NormalCitation False)
  , ("parencite", citation "parencite" NormalCitation False)
  , ("supercite", citation "supercite" NormalCitation False)
  , ("footcitetext", inNote <$> citation "footcitetext" NormalCitation False)
  , ("citeyearpar", citation "citeyearpar" SuppressAuthor False)
  , ("citeyear", citation "citeyear" SuppressAuthor False)
  , ("autocite*", citation "autocite*" SuppressAuthor False)
  , ("cite*", citation "cite*" SuppressAuthor False)
  , ("parencite*", citation "parencite*" SuppressAuthor False)
  , ("textcite", citation "textcite" AuthorInText False)
  , ("citet", citation "citet" AuthorInText False)
  , ("citet*", citation "citet*" AuthorInText False)
  , ("citealt", citation "citealt" AuthorInText False)
  , ("citealt*", citation "citealt*" AuthorInText False)
  , ("textcites", citation "textcites" AuthorInText True)
  , ("cites", citation "cites" NormalCitation True)
  , ("autocites", citation "autocites" NormalCitation True)
  , ("footcites", inNote <$> citation "footcites" NormalCitation True)
  , ("parencites", citation "parencites" NormalCitation True)
  , ("supercites", citation "supercites" NormalCitation True)
  , ("footcitetexts", inNote <$> citation "footcitetexts" NormalCitation True)
  , ("Autocite", citation "Autocite" NormalCitation False)
  , ("Smartcite", citation "Smartcite" NormalCitation False)
  , ("Footcite", citation "Footcite" NormalCitation False)
  , ("Parencite", citation "Parencite" NormalCitation False)
  , ("Supercite", citation "Supercite" NormalCitation False)
  , ("Footcitetext", inNote <$> citation "Footcitetext" NormalCitation False)
  , ("Citeyearpar", citation "Citeyearpar" SuppressAuthor False)
  , ("Citeyear", citation "Citeyear" SuppressAuthor False)
  , ("Autocite*", citation "Autocite*" SuppressAuthor False)
  , ("Cite*", citation "Cite*" SuppressAuthor False)
  , ("Parencite*", citation "Parencite*" SuppressAuthor False)
  , ("Textcite", citation "Textcite" AuthorInText False)
  , ("Textcites", citation "Textcites" AuthorInText True)
  , ("Cites", citation "Cites" NormalCitation True)
  , ("Autocites", citation "Autocites" NormalCitation True)
  , ("Footcites", citation "Footcites" NormalCitation True)
  , ("Parencites", citation "Parencites" NormalCitation True)
  , ("Supercites", citation "Supercites" NormalCitation True)
  , ("Footcitetexts", inNote <$> citation "Footcitetexts" NormalCitation True)
  , ("citetext", complexNatbibCitation NormalCitation)
  , ("citeauthor", (try (tok *> optional sp *> controlSeq "citetext") *>
                        complexNatbibCitation AuthorInText)
                   <|> citation "citeauthor" AuthorInText False)
  , ("nocite", mempty <$ (citation "nocite" NormalCitation False >>=
                          addMeta "nocite"))
  , ("hyperlink", hyperlink)
  , ("hypertarget", hypertargetInline)
  -- glossaries package
  , ("gls", doAcronym "short")
  , ("Gls", doAcronym "short")
  , ("glsdesc", doAcronym "long")
  , ("Glsdesc", doAcronym "long")
  , ("GLSdesc", doAcronym "long")
  , ("acrlong", doAcronym "long")
  , ("Acrlong", doAcronym "long")
  , ("acrfull", doAcronym "full")
  , ("Acrfull", doAcronym "full")
  , ("acrshort", doAcronym "abbrv")
  , ("Acrshort", doAcronym "abbrv")
  , ("glspl", doAcronymPlural "short")
  , ("Glspl", doAcronymPlural "short")
  , ("glsdescplural", doAcronymPlural "long")
  , ("Glsdescplural", doAcronymPlural "long")
  , ("GLSdescplural", doAcronymPlural "long")
  -- acronyms package
  , ("ac", doAcronym "short")
  , ("acf", doAcronym "full")
  , ("acs", doAcronym "abbrv")
  , ("acp", doAcronymPlural "short")
  , ("acfp", doAcronymPlural "full")
  , ("acsp", doAcronymPlural "abbrv")
  -- siuntix
  , ("SI", dosiunitx)
  -- hyphenat
  , ("bshyp", lit "\\\173")
  , ("fshyp", lit "/\173")
  , ("dothyp", lit ".\173")
  , ("colonhyp", lit ":\173")
  , ("hyp", lit "-")
  , ("nohyphens", tok)
  , ("textnhtt", ttfamily)
  , ("nhttfamily", ttfamily)
  -- LaTeX colors
  , ("textcolor", coloredInline "color")
  , ("colorbox", coloredInline "background-color")
  -- fontawesome
  , ("faCheck", lit "\10003")
  , ("faClose", lit "\10007")
  -- xspace
  , ("xspace", doxspace)
  -- etoolbox
  , ("ifstrequal", ifstrequal)
  , ("newtoggle", braced >>= newToggle)
  , ("toggletrue", braced >>= setToggle True)
  , ("togglefalse", braced >>= setToggle False)
  , ("iftoggle", try $ ifToggle >> inline)
  -- biblatex misc
  , ("RN", romanNumeralUpper)
  , ("Rn", romanNumeralLower)
  -- babel
  , ("foreignlanguage", foreignlanguage)
  -- include
  , ("input", include "input")
  -- plain tex stuff that should just be passed through as raw tex
  , ("ifdim", ifdim)
  ]

ifdim :: PandocMonad m => LP m Inlines
ifdim = do
  contents <- manyTill anyTok (controlSeq "fi")
  return $ rawInline "latex" $ T.unpack $
           "\\ifdim" <> untokenize contents <> "\\fi"

makeUppercase :: Inlines -> Inlines
makeUppercase = fromList . walk (alterStr (map toUpper)) . toList

makeLowercase :: Inlines -> Inlines
makeLowercase = fromList . walk (alterStr (map toLower)) . toList

alterStr :: (String -> String) -> Inline -> Inline
alterStr f (Str xs) = Str (f xs)
alterStr _ x = x

foreignlanguage :: PandocMonad m => LP m Inlines
foreignlanguage = do
  babelLang <- T.unpack . untokenize <$> braced
  case babelLangToBCP47 babelLang of
       Just lang -> spanWith ("", [], [("lang",  renderLang lang)]) <$> tok
       _ -> tok

inlineLanguageCommands :: PandocMonad m => M.Map Text (LP m Inlines)
inlineLanguageCommands = M.fromList $ mk <$> M.toList polyglossiaLangToBCP47
  where
    mk (polyglossia, bcp47Func) =
      ("text" <> T.pack polyglossia, inlineLanguage bcp47Func)

inlineLanguage :: PandocMonad m => (String -> Lang) -> LP m Inlines
inlineLanguage bcp47Func = do
  o <- option "" $ (T.unpack . T.filter (\c -> c /= '[' && c /= ']'))
                <$> rawopt
  let lang = renderLang $ bcp47Func o
  extractSpaces (spanWith ("", [], [("lang", lang)])) <$> tok

hyperlink :: PandocMonad m => LP m Inlines
hyperlink = try $ do
  src <- toksToString <$> braced
  lab <- tok
  return $ link ('#':src) "" lab

hypertargetBlock :: PandocMonad m => LP m Blocks
hypertargetBlock = try $ do
  ref <- toksToString <$> braced
  bs <- grouped block
  case toList bs of
       [Header 1 (ident,_,_) _] | ident == ref -> return bs
       _                        -> return $ divWith (ref, [], []) bs

hypertargetInline :: PandocMonad m => LP m Inlines
hypertargetInline = try $ do
  ref <- toksToString <$> braced
  ils <- grouped inline
  return $ spanWith (ref, [], []) ils

romanNumeralUpper :: (PandocMonad m) => LP m Inlines
romanNumeralUpper =
  str . toRomanNumeral <$> romanNumeralArg

romanNumeralLower :: (PandocMonad m) => LP m Inlines
romanNumeralLower =
  str . map toLower . toRomanNumeral <$> romanNumeralArg

romanNumeralArg :: (PandocMonad m) => LP m Int
romanNumeralArg = spaces *> (parser <|> inBraces)
  where
    inBraces = do
      symbol '{'
      spaces
      res <- parser
      spaces
      symbol '}'
      return res
    parser = do
      Tok _ Word s <- satisfyTok isWordTok
      let (digits, rest) = T.span isDigit s
      unless (T.null rest) $
        fail "Non-digits in argument to \\Rn or \\RN"
      safeRead $ T.unpack digits

newToggle :: (Monoid a, PandocMonad m) => [Tok] -> LP m a
newToggle name = do
  updateState $ \st ->
    st{ sToggles = M.insert (toksToString name) False (sToggles st) }
  return mempty

setToggle :: (Monoid a, PandocMonad m) => Bool -> [Tok] -> LP m a
setToggle on name = do
  updateState $ \st ->
    st{ sToggles = M.adjust (const on) (toksToString name) (sToggles st) }
  return mempty

ifToggle :: PandocMonad m => LP m ()
ifToggle = do
  name <- braced
  spaces
  yes <- braced
  spaces
  no <- braced
  toggles <- sToggles <$> getState
  inp <- getInput
  let name' = toksToString name
  case M.lookup name' toggles of
                Just True  -> setInput (yes ++ inp)
                Just False -> setInput (no  ++ inp)
                Nothing    -> do
                  pos <- getPosition
                  report $ UndefinedToggle name' pos
  return ()

doTerm :: PandocMonad m => Translations.Term -> LP m Inlines
doTerm term = str <$> translateTerm term

ifstrequal :: (PandocMonad m, Monoid a) => LP m a
ifstrequal = do
  str1 <- tok
  str2 <- tok
  ifequal <- braced
  ifnotequal <- braced
  if str1 == str2
     then getInput >>= setInput . (ifequal ++)
     else getInput >>= setInput . (ifnotequal ++)
  return mempty

coloredInline :: PandocMonad m => String -> LP m Inlines
coloredInline stylename = do
  skipopts
  color <- braced
  spanWith ("",[],[("style",stylename ++ ": " ++ toksToString color)]) <$> tok

ttfamily :: PandocMonad m => LP m Inlines
ttfamily = (code . stringify . toList) <$> tok

rawInlineOr :: PandocMonad m => Text -> LP m Inlines -> LP m Inlines
rawInlineOr name' fallback = do
  parseRaw <- extensionEnabled Ext_raw_tex <$> getOption readerExtensions
  if parseRaw
     then rawInline "latex" <$> getRawCommand name' ("\\" <> name')
     else fallback

getRawCommand :: PandocMonad m => Text -> Text -> LP m String
getRawCommand name txt = do
  (_, rawargs) <- withRaw $
      case name of
           "write" -> do
             void $ satisfyTok isWordTok -- digits
             void braced
           "titleformat" -> do
             void braced
             skipopts
             void $ count 4 braced
           "def" ->
             void $ manyTill anyTok braced
           _ -> do
             skipopts
             option "" (try (optional sp *> dimenarg))
             void $ many braced
  return $ T.unpack (txt <> untokenize rawargs)

isBlockCommand :: Text -> Bool
isBlockCommand s =
  s `M.member` (blockCommands :: M.Map Text (LP PandocPure Blocks))
  || s `Set.member` treatAsBlock

treatAsBlock :: Set.Set Text
treatAsBlock = Set.fromList
   [ "let", "def", "DeclareRobustCommand"
   , "newcommand", "renewcommand"
   , "newenvironment", "renewenvironment"
   , "providecommand", "provideenvironment"
     -- newcommand, etc. should be parsed by macroDef, but we need this
     -- here so these aren't parsed as inline commands to ignore
   , "special", "pdfannot", "pdfstringdef"
   , "bibliographystyle"
   , "maketitle", "makeindex", "makeglossary"
   , "addcontentsline", "addtocontents", "addtocounter"
      -- \ignore{} is used conventionally in literate haskell for definitions
      -- that are to be processed by the compiler but not printed.
   , "ignore"
   , "hyperdef"
   , "markboth", "markright", "markleft"
   , "hspace", "vspace"
   , "newpage"
   , "clearpage"
   , "pagebreak"
   , "titleformat"
   , "listoffigures"
   , "listoftables"
   , "write"
   ]

isInlineCommand :: Text -> Bool
isInlineCommand s =
  s `M.member` (inlineCommands :: M.Map Text (LP PandocPure Inlines))
  || s `Set.member` treatAsInline

treatAsInline :: Set.Set Text
treatAsInline = Set.fromList
  [ "index"
  , "hspace"
  , "vspace"
  , "noindent"
  , "newpage"
  , "clearpage"
  , "pagebreak"
  ]

dolabel :: PandocMonad m => LP m Inlines
dolabel = do
  v <- braced
  let refstr = toksToString v
  return $ spanWith (refstr,[],[("label", refstr)])
    $ inBrackets $ str $ toksToString v

doref :: PandocMonad m => String -> LP m Inlines
doref cls = do
  v <- braced
  let refstr = toksToString v
  return $ linkWith ("",[],[ ("reference-type", cls)
                           , ("reference", refstr)])
                    ('#':refstr)
                    ""
                    (inBrackets $ str refstr)

lookupListDefault :: (Show k, Ord k) => v -> [k] -> M.Map k v -> v
lookupListDefault d = (fromMaybe d .) . lookupList
  where lookupList l m = msum $ map (`M.lookup` m) l

inline :: PandocMonad m => LP m Inlines
inline = (mempty <$ comment)
     <|> (space  <$ whitespace)
     <|> (softbreak <$ endline)
     <|> word
     <|> inlineCommand'
     <|> inlineEnvironment
     <|> inlineGroup
     <|> (symbol '-' *>
           option (str "-") (symbol '-' *>
             option (str "–") (str "—" <$ symbol '-')))
     <|> doubleQuote
     <|> singleQuote
     <|> (str "”" <$ try (symbol '\'' >> symbol '\''))
     <|> (str "”" <$ symbol '”')
     <|> (str "’" <$ symbol '\'')
     <|> (str "’" <$ symbol '’')
     <|> (str "\160" <$ symbol '~')
     <|> dollarsMath
     <|> (guardEnabled Ext_literate_haskell *> symbol '|' *> doLHSverb)
     <|> (str . (:[]) <$> primEscape)
     <|> regularSymbol
     <|> (do res <- symbolIn "#^'`\"[]&"
             pos <- getPosition
             let s = T.unpack (untoken res)
             report $ ParsingUnescaped s pos
             return $ str s)

inlines :: PandocMonad m => LP m Inlines
inlines = mconcat <$> many inline

-- block elements:

begin_ :: PandocMonad m => Text -> LP m ()
begin_ t = try (do
  controlSeq "begin"
  spaces
  txt <- untokenize <$> braced
  guard (t == txt)) <?> ("\\begin{" ++ T.unpack t ++ "}")

end_ :: PandocMonad m => Text -> LP m ()
end_ t = try (do
  controlSeq "end"
  spaces
  txt <- untokenize <$> braced
  guard $ t == txt) <?> ("\\end{" ++ T.unpack t ++ "}")

preamble :: PandocMonad m => LP m Blocks
preamble = mempty <$ many preambleBlock
  where preambleBlock =  spaces1
                     <|> void macroDef
                     <|> void blockCommand
                     <|> void braced
                     <|> (notFollowedBy (begin_ "document") >> void anyTok)

paragraph :: PandocMonad m => LP m Blocks
paragraph = do
  x <- trimInlines . mconcat <$> many1 inline
  if x == mempty
     then return mempty
     else return $ para x

include :: (PandocMonad m, Monoid a) => Text -> LP m a
include name = do
  skipMany opt
  fs <- (map (T.unpack . removeDoubleQuotes . T.strip) . T.splitOn "," .
         untokenize) <$> braced
  let fs' = if name == "usepackage"
               then map (maybeAddExtension ".sty") fs
               else map (maybeAddExtension ".tex") fs
  dirs <- (splitBy (==':') . fromMaybe ".") <$> lookupEnv "TEXINPUTS"
  mapM_ (insertIncluded dirs) fs'
  return mempty

insertIncluded :: PandocMonad m
               => [FilePath]
               -> FilePath
               -> LP m ()
insertIncluded dirs f = do
  pos <- getPosition
  containers <- getIncludeFiles <$> getState
  when (f `elem` containers) $
    throwError $ PandocParseError $ "Include file loop at " ++ show pos
  updateState $ addIncludeFile f
  mbcontents <- readFileFromDirs dirs f
  contents <- case mbcontents of
                   Just s -> return s
                   Nothing -> do
                     report $ CouldNotLoadIncludeFile f pos
                     return ""
  getInput >>= setInput . (tokenize f (T.pack contents) ++)
  updateState dropLatestIncludeFile

maybeAddExtension :: String -> FilePath -> FilePath
maybeAddExtension ext fp =
  if null (takeExtension fp)
     then addExtension fp ext
     else fp

addMeta :: PandocMonad m => ToMetaValue a => String -> a -> LP m ()
addMeta field val = updateState $ \st ->
   st{ sMeta = addMetaField field val $ sMeta st }

authors :: PandocMonad m => LP m ()
authors = try $ do
  bgroup
  let oneAuthor = mconcat <$>
       many1 (notFollowedBy' (controlSeq "and") >>
               (inline <|> mempty <$ blockCommand))
               -- skip e.g. \vspace{10pt}
  auths <- sepBy oneAuthor (controlSeq "and")
  egroup
  addMeta "author" (map trimInlines auths)

macroDef :: PandocMonad m => LP m Blocks
macroDef =
  mempty <$ ((commandDef <|> environmentDef) <* doMacros 0)
  where commandDef = do
          (name, macro') <- newcommand <|> letmacro <|> defmacro
          guardDisabled Ext_latex_macros <|>
           updateState (\s -> s{ sMacros = M.insert name macro' (sMacros s) })
        environmentDef = do
          (name, macro1, macro2) <- newenvironment
          guardDisabled Ext_latex_macros <|>
            do updateState $ \s -> s{ sMacros =
                M.insert name macro1 (sMacros s) }
               updateState $ \s -> s{ sMacros =
                M.insert ("end" <> name) macro2 (sMacros s) }
        -- @\newenvironment{envname}[n-args][default]{begin}{end}@
        -- is equivalent to
        -- @\newcommand{\envname}[n-args][default]{begin}@
        -- @\newcommand{\endenvname}@

letmacro :: PandocMonad m => LP m (Text, Macro)
letmacro = do
  controlSeq "let"
  Tok _ (CtrlSeq name) _ <- anyControlSeq
  optional $ symbol '='
  spaces
  contents <- bracedOrToken
  return (name, Macro ExpandWhenDefined [] Nothing contents)

defmacro :: PandocMonad m => LP m (Text, Macro)
defmacro = try $ do
  controlSeq "def"
  Tok _ (CtrlSeq name) _ <- anyControlSeq
  argspecs <- many (argspecArg <|> argspecPattern)
  -- we use withVerbatimMode, because macros are to be expanded
  -- at point of use, not point of definition
  contents <- withVerbatimMode bracedOrToken
  return (name, Macro ExpandWhenUsed argspecs Nothing contents)

argspecArg :: PandocMonad m => LP m ArgSpec
argspecArg = do
  Tok _ (Arg i) _ <- satisfyTok isArgTok
  return $ ArgNum i

argspecPattern :: PandocMonad m => LP m ArgSpec
argspecPattern =
  Pattern <$> many1 (satisfyTok (\(Tok _ toktype' txt) ->
                                    (toktype' == Symbol || toktype' == Word) &&
                                    (txt /= "{" && txt /= "\\" && txt /= "}")))

isArgTok :: Tok -> Bool
isArgTok (Tok _ (Arg _) _) = True
isArgTok _                 = False

newcommand :: PandocMonad m => LP m (Text, Macro)
newcommand = do
  pos <- getPosition
  Tok _ (CtrlSeq mtype) _ <- controlSeq "newcommand" <|>
                             controlSeq "renewcommand" <|>
                             controlSeq "providecommand" <|>
                             controlSeq "DeclareRobustCommand"
  optional $ symbol '*'
  Tok _ (CtrlSeq name) txt <- withVerbatimMode $ anyControlSeq <|>
    (symbol '{' *> spaces *> anyControlSeq <* spaces <* symbol '}')
  spaces
  numargs <- option 0 $ try bracketedNum
  let argspecs = map (\i -> ArgNum i) [1..numargs]
  spaces
  optarg <- option Nothing $ Just <$> try bracketedToks
  spaces
  contents <- withVerbatimMode bracedOrToken
  when (mtype == "newcommand") $ do
    macros <- sMacros <$> getState
    case M.lookup name macros of
         Just _  -> report $ MacroAlreadyDefined (T.unpack txt) pos
         Nothing -> return ()
  return (name, Macro ExpandWhenUsed argspecs optarg contents)

newenvironment :: PandocMonad m => LP m (Text, Macro, Macro)
newenvironment = do
  pos <- getPosition
  Tok _ (CtrlSeq mtype) _ <- controlSeq "newenvironment" <|>
                             controlSeq "renewenvironment" <|>
                             controlSeq "provideenvironment"
  optional $ symbol '*'
  spaces
  name <- untokenize <$> braced
  spaces
  numargs <- option 0 $ try bracketedNum
  let argspecs = map (\i -> ArgNum i) [1..numargs]
  spaces
  optarg <- option Nothing $ Just <$> try bracketedToks
  spaces
  startcontents <- withVerbatimMode bracedOrToken
  spaces
  endcontents <- withVerbatimMode bracedOrToken
  when (mtype == "newenvironment") $ do
    macros <- sMacros <$> getState
    case M.lookup name macros of
         Just _  -> report $ MacroAlreadyDefined (T.unpack name) pos
         Nothing -> return ()
  return (name, Macro ExpandWhenUsed argspecs optarg startcontents,
             Macro ExpandWhenUsed [] Nothing endcontents)

bracketedNum :: PandocMonad m => LP m Int
bracketedNum = do
  ds <- untokenize <$> bracketedToks
  case safeRead (T.unpack ds) of
       Just i -> return i
       _      -> return 0

setCaption :: PandocMonad m => LP m Blocks
setCaption = do
  ils <- tok
  mblabel <- option Nothing $
               try $ spaces >> controlSeq "label" >> (Just <$> tok)
  let capt = case mblabel of
                  Just lab -> let slab = stringify lab
                                  ils' = ils <> spanWith
                                    ("",[],[("label", slab)]) mempty
                              in  (Just ils', Just slab)
                  Nothing  -> (Just ils, Nothing)
  updateState $ \st -> st{ sCaption = capt }
  return mempty

looseItem :: PandocMonad m => LP m Blocks
looseItem = do
  inListItem <- sInListItem <$> getState
  guard $ not inListItem
  skipopts
  return mempty

resetCaption :: PandocMonad m => LP m ()
resetCaption = updateState $ \st -> st{ sCaption = (Nothing, Nothing) }

section :: PandocMonad m => Attr -> Int -> LP m Blocks
section (ident, classes, kvs) lvl = do
  skipopts
  contents <- grouped inline
  lab <- option ident $
          try (spaces >> controlSeq "label"
               >> spaces >> toksToString <$> braced)
  when (lvl == 0) $
    updateState $ \st -> st{ sHasChapters = True }
  unless ("unnumbered" `elem` classes) $ do
    hn <- sLastHeaderNum <$> getState
    hasChapters <- sHasChapters <$> getState
    let lvl' = lvl + if hasChapters then 1 else 0
    let num = incrementDottedNum lvl' hn
    updateState $ \st -> st{ sLastHeaderNum = num
                           , sLabels = M.insert lab
                              [Str (renderDottedNum num)]
                              (sLabels st) }
  attr' <- registerHeader (lab, classes, kvs) contents
  return $ headerWith attr' lvl contents

blockCommand :: PandocMonad m => LP m Blocks
blockCommand = try $ do
  Tok _ (CtrlSeq name) txt <- anyControlSeq
  guard $ name /= "begin" && name /= "end"
  star <- option "" ("*" <$ symbol '*' <* optional sp)
  let name' = name <> star
  let names = ordNub [name', name]
  let rawDefiniteBlock = do
        guard $ isBlockCommand name
        rawBlock "latex" <$> getRawCommand name (txt <> star)
  -- heuristic:  if it could be either block or inline, we
  -- treat it if block if we have a sequence of block
  -- commands followed by a newline.  But we stop if we
  -- hit a \startXXX, since this might start a raw ConTeXt
  -- environment (this is important because this parser is
  -- used by the Markdown reader).
  let startCommand = try $ do
        Tok _ (CtrlSeq n) _ <- anyControlSeq
        guard $ "start" `T.isPrefixOf` n
  let rawMaybeBlock = try $ do
        guard $ not $ isInlineCommand name
        curr <- rawBlock "latex" <$> getRawCommand name (txt <> star)
        rest <- many $ notFollowedBy startCommand *> blockCommand
        lookAhead $ blankline <|> startCommand
        return $ curr <> mconcat rest
  let raw = rawDefiniteBlock <|> rawMaybeBlock
  lookupListDefault raw names blockCommands

closing :: PandocMonad m => LP m Blocks
closing = do
  contents <- tok
  st <- getState
  let extractInlines (MetaBlocks [Plain ys]) = ys
      extractInlines (MetaBlocks [Para ys ]) = ys
      extractInlines _                       = []
  let sigs = case lookupMeta "author" (sMeta st) of
                  Just (MetaList xs) ->
                    para $ trimInlines $ fromList $
                      intercalate [LineBreak] $ map extractInlines xs
                  _ -> mempty
  return $ para (trimInlines contents) <> sigs

blockCommands :: PandocMonad m => M.Map Text (LP m Blocks)
blockCommands = M.fromList
   [ ("par", mempty <$ skipopts)
   , ("parbox",  skipopts >> braced >> grouped blocks)
   , ("title", mempty <$ (skipopts *>
                             (grouped inline >>= addMeta "title")
                         <|> (grouped block >>= addMeta "title")))
   , ("subtitle", mempty <$ (skipopts *> tok >>= addMeta "subtitle"))
   , ("author", mempty <$ (skipopts *> authors))
   -- -- in letter class, temp. store address & sig as title, author
   , ("address", mempty <$ (skipopts *> tok >>= addMeta "address"))
   , ("signature", mempty <$ (skipopts *> authors))
   , ("date", mempty <$ (skipopts *> tok >>= addMeta "date"))
   -- Koma-script metadata commands
   , ("dedication", mempty <$ (skipopts *> tok >>= addMeta "dedication"))
   -- sectioning
   , ("part", section nullAttr (-1))
   , ("part*", section nullAttr (-1))
   , ("chapter", section nullAttr 0)
   , ("chapter*", section ("",["unnumbered"],[]) 0)
   , ("section", section nullAttr 1)
   , ("section*", section ("",["unnumbered"],[]) 1)
   , ("subsection", section nullAttr 2)
   , ("subsection*", section ("",["unnumbered"],[]) 2)
   , ("subsubsection", section nullAttr 3)
   , ("subsubsection*", section ("",["unnumbered"],[]) 3)
   , ("paragraph", section nullAttr 4)
   , ("paragraph*", section ("",["unnumbered"],[]) 4)
   , ("subparagraph", section nullAttr 5)
   , ("subparagraph*", section ("",["unnumbered"],[]) 5)
   -- beamer slides
   , ("frametitle", section nullAttr 3)
   , ("framesubtitle", section nullAttr 4)
   -- letters
   , ("opening", (para . trimInlines) <$> (skipopts *> tok))
   , ("closing", skipopts *> closing)
   -- memoir
   , ("plainbreak", braced >> pure horizontalRule)
   , ("plainbreak*", braced >> pure horizontalRule)
   , ("fancybreak", braced >> pure horizontalRule)
   , ("fancybreak*", braced >> pure horizontalRule)
   , ("plainfancybreak", braced >> braced >> braced >> pure horizontalRule)
   , ("plainfancybreak*", braced >> braced >> braced >> pure horizontalRule)
   , ("pfbreak", pure horizontalRule)
   , ("pfbreak*", pure horizontalRule)
   --
   , ("hrule", pure horizontalRule)
   , ("strut", pure mempty)
   , ("rule", skipopts *> tok *> tok *> pure horizontalRule)
   , ("item", looseItem)
   , ("documentclass", skipopts *> braced *> preamble)
   , ("centerline", (para . trimInlines) <$> (skipopts *> tok))
   , ("caption", skipopts *> setCaption)
   , ("bibliography", mempty <$ (skipopts *> braced >>=
         addMeta "bibliography" . splitBibs . toksToString))
   , ("addbibresource", mempty <$ (skipopts *> braced >>=
         addMeta "bibliography" . splitBibs . toksToString))
   -- includes
   , ("lstinputlisting", inputListing)
   , ("graphicspath", graphicsPath)
   -- polyglossia
   , ("setdefaultlanguage", setDefaultLanguage)
   , ("setmainlanguage", setDefaultLanguage)
   -- hyperlink
   , ("hypertarget", hypertargetBlock)
   -- LaTeX colors
   , ("textcolor", coloredBlock "color")
   , ("colorbox", coloredBlock "background-color")
   -- csquotes
   , ("blockquote", blockquote False Nothing)
   , ("blockcquote", blockquote True Nothing)
   , ("foreignblockquote", braced >>= blockquote False . Just . untokenize)
   , ("foreignblockcquote", braced >>= blockquote True . Just . untokenize)
   , ("hyphenblockquote", braced >>= blockquote False . Just . untokenize)
   , ("hyphenblockcquote", braced >>= blockquote True . Just . untokenize)
   -- include
   , ("include", include "include")
   , ("input", include "input")
   , ("subfile", include "subfile")
   , ("usepackage", include "usepackage")
   ]


environments :: PandocMonad m => M.Map Text (LP m Blocks)
environments = M.fromList
   [ ("document", env "document" blocks)
   , ("abstract", mempty <$ (env "abstract" blocks >>= addMeta "abstract"))
   , ("sloppypar", env "sloppypar" $ blocks)
   , ("letter", env "letter" letterContents)
   , ("minipage", env "minipage" $
          skipopts *> spaces *> optional braced *> spaces *> blocks)
   , ("figure", env "figure" $ skipopts *> figure)
   , ("subfigure", env "subfigure" $ skipopts *> tok *> figure)
   , ("center", env "center" blocks)
   , ("longtable",  env "longtable" $
          resetCaption *> simpTable "longtable" False >>= addTableCaption)
   , ("table",  env "table" $
          resetCaption *> skipopts *> blocks >>= addTableCaption)
   , ("tabular*", env "tabular*" $ simpTable "tabular*" True)
   , ("tabularx", env "tabularx" $ simpTable "tabularx" True)
   , ("tabular", env "tabular"  $ simpTable "tabular" False)
   , ("quote", blockQuote <$> env "quote" blocks)
   , ("quotation", blockQuote <$> env "quotation" blocks)
   , ("verse", blockQuote <$> env "verse" blocks)
   , ("itemize", bulletList <$> listenv "itemize" (many item))
   , ("description", definitionList <$> listenv "description" (many descItem))
   , ("enumerate", orderedList')
   , ("alltt", alltt <$> env "alltt" blocks)
   , ("code", guardEnabled Ext_literate_haskell *>
       (codeBlockWith ("",["sourceCode","literate","haskell"],[]) <$>
         verbEnv "code"))
   , ("comment", mempty <$ verbEnv "comment")
   , ("verbatim", codeBlock <$> verbEnv "verbatim")
   , ("Verbatim", fancyverbEnv "Verbatim")
   , ("BVerbatim", fancyverbEnv "BVerbatim")
   , ("lstlisting", do attr <- parseListingsOptions <$> option [] keyvals
                       codeBlockWith attr <$> verbEnv "lstlisting")
   , ("minted", minted)
   , ("obeylines", obeylines)
   , ("tikzpicture", rawVerbEnv "tikzpicture")
   , ("lilypond", rawVerbEnv "lilypond")
   -- etoolbox
   , ("ifstrequal", ifstrequal)
   , ("newtoggle", braced >>= newToggle)
   , ("toggletrue", braced >>= setToggle True)
   , ("togglefalse", braced >>= setToggle False)
   , ("iftoggle", try $ ifToggle >> block)
   ]

environment :: PandocMonad m => LP m Blocks
environment = try $ do
  controlSeq "begin"
  name <- untokenize <$> braced
  M.findWithDefault mzero name environments <|>
    if M.member name (inlineEnvironments
                       :: M.Map Text (LP PandocPure Inlines))
       then mzero
       else rawEnv name

env :: PandocMonad m => Text -> LP m a -> LP m a
env name p = p <* end_ name

rawEnv :: PandocMonad m => Text -> LP m Blocks
rawEnv name = do
  exts <- getOption readerExtensions
  let parseRaw = extensionEnabled Ext_raw_tex exts
  rawOptions <- mconcat <$> many rawopt
  let beginCommand = "\\begin{" <> name <> "}" <> rawOptions
  pos1 <- getPosition
  (bs, raw) <- withRaw $ env name blocks
  if parseRaw
     then return $ rawBlock "latex"
                 $ T.unpack $ beginCommand <> untokenize raw
     else do
       report $ SkippedContent (T.unpack beginCommand) pos1
       pos2 <- getPosition
       report $ SkippedContent ("\\end{" ++ T.unpack name ++ "}") pos2
       return bs

rawVerbEnv :: PandocMonad m => Text -> LP m Blocks
rawVerbEnv name = do
  pos <- getPosition
  (_, raw) <- withRaw $ verbEnv name
  let raw' = "\\begin{" ++ T.unpack name ++ "}" ++ toksToString raw
  exts <- getOption readerExtensions
  let parseRaw = extensionEnabled Ext_raw_tex exts
  if parseRaw
     then return $ rawBlock "latex" raw'
     else do
       report $ SkippedContent raw' pos
       return mempty

verbEnv :: PandocMonad m => Text -> LP m String
verbEnv name = withVerbatimMode $ do
  skipopts
  optional blankline
  res <- manyTill anyTok (end_ name)
  return $ T.unpack
         $ stripTrailingNewline
         $ untokenize
         $ res

-- Strip single final newline and any spaces following it.
-- Input is unchanged if it doesn't end with newline +
-- optional spaces.
stripTrailingNewline :: Text -> Text
stripTrailingNewline t =
  let (b, e) = T.breakOnEnd "\n" t
  in  if T.all (== ' ') e
         then T.dropEnd 1 b
         else t

fancyverbEnv :: PandocMonad m => Text -> LP m Blocks
fancyverbEnv name = do
  options <- option [] keyvals
  let kvs = [ (if k == "firstnumber"
                  then "startFrom"
                  else k, v) | (k,v) <- options ]
  let classes = [ "numberLines" |
                  lookup "numbers" options == Just "left" ]
  let attr = ("",classes,kvs)
  codeBlockWith attr <$> verbEnv name

obeylines :: PandocMonad m => LP m Blocks
obeylines =
  para . fromList . removeLeadingTrailingBreaks .
   walk softBreakToHard . toList <$> env "obeylines" inlines
  where softBreakToHard SoftBreak = LineBreak
        softBreakToHard x         = x
        removeLeadingTrailingBreaks = reverse . dropWhile isLineBreak .
                                      reverse . dropWhile isLineBreak
        isLineBreak LineBreak = True
        isLineBreak _         = False

minted :: PandocMonad m => LP m Blocks
minted = do
  options <- option [] keyvals
  lang <- toksToString <$> braced
  let kvs = [ (if k == "firstnumber"
                  then "startFrom"
                  else k, v) | (k,v) <- options ]
  let classes = [ lang | not (null lang) ] ++
                [ "numberLines" |
                  lookup "linenos" options == Just "true" ]
  let attr = ("",classes,kvs)
  codeBlockWith attr <$> verbEnv "minted"

letterContents :: PandocMonad m => LP m Blocks
letterContents = do
  bs <- blocks
  st <- getState
  -- add signature (author) and address (title)
  let addr = case lookupMeta "address" (sMeta st) of
                  Just (MetaBlocks [Plain xs]) ->
                     para $ trimInlines $ fromList xs
                  _ -> mempty
  return $ addr <> bs -- sig added by \closing

figure :: PandocMonad m => LP m Blocks
figure = try $ do
  resetCaption
  blocks >>= addImageCaption

addImageCaption :: PandocMonad m => Blocks -> LP m Blocks
addImageCaption = walkM go
  where go (Image attr@(_, cls, kvs) alt (src,tit))
            | not ("fig:" `isPrefixOf` tit) = do
          (mbcapt, mblab) <- sCaption <$> getState
          let (alt', tit') = case mbcapt of
                               Just ils -> (toList ils, "fig:" ++ tit)
                               Nothing  -> (alt, tit)
              attr' = case mblab of
                        Just lab -> (lab, cls, kvs)
                        Nothing  -> attr
          case attr' of
               ("", _, _)    -> return ()
               (ident, _, _) -> do
                  st <- getState
                  let chapnum =
                        case (sHasChapters st, sLastHeaderNum st) of
                             (True, DottedNum (n:_)) -> Just n
                             _                       -> Nothing
                  let num = case sLastFigureNum st of
                       DottedNum [m,n]  ->
                         case chapnum of
                              Just m' | m' == m   -> DottedNum [m, n+1]
                                      | otherwise -> DottedNum [m', 1]
                              Nothing             -> DottedNum [1]
                                                      -- shouldn't happen
                       DottedNum [n]   ->
                         case chapnum of
                              Just m  -> DottedNum [m, 1]
                              Nothing -> DottedNum [n + 1]
                       _               ->
                         case chapnum of
                               Just n  -> DottedNum [n, 1]
                               Nothing -> DottedNum [1]
                  setState $
                    st{ sLastFigureNum = num
                      , sLabels = M.insert ident
                                 [Str (renderDottedNum num)] (sLabels st) }
          return $ Image attr' alt' (src, tit')
        go x = return x

coloredBlock :: PandocMonad m => String -> LP m Blocks
coloredBlock stylename = try $ do
  skipopts
  color <- braced
  notFollowedBy (grouped inline)
  let constructor = divWith ("",[],[("style",stylename ++ ": " ++ toksToString color)])
  constructor <$> grouped block

graphicsPath :: PandocMonad m => LP m Blocks
graphicsPath = do
  ps <- map toksToString <$>
          (bgroup *> spaces *> manyTill (braced <* spaces) egroup)
  getResourcePath >>= setResourcePath . (++ ps)
  return mempty

splitBibs :: String -> [Inlines]
splitBibs = map (str . flip replaceExtension "bib" . trim) . splitBy (==',')

alltt :: Blocks -> Blocks
alltt = walk strToCode
  where strToCode (Str s)   = Code nullAttr s
        strToCode Space     = RawInline (Format "latex") "\\ "
        strToCode SoftBreak = LineBreak
        strToCode x         = x

parseListingsOptions :: [(String, String)] -> Attr
parseListingsOptions options =
  let kvs = [ (if k == "firstnumber"
                  then "startFrom"
                  else k, v) | (k,v) <- options ]
      classes = [ "numberLines" |
                  lookup "numbers" options == Just "left" ]
             ++ maybeToList (lookup "language" options
                     >>= fromListingsLanguage)
  in  (fromMaybe "" (lookup "label" options), classes, kvs)

inputListing :: PandocMonad m => LP m Blocks
inputListing = do
  pos <- getPosition
  options <- option [] keyvals
  f <- filter (/='"') . toksToString <$> braced
  dirs <- (splitBy (==':') . fromMaybe ".") <$> lookupEnv "TEXINPUTS"
  mbCode <- readFileFromDirs dirs f
  codeLines <- case mbCode of
                      Just s -> return $ lines s
                      Nothing -> do
                        report $ CouldNotLoadIncludeFile f pos
                        return []
  let (ident,classes,kvs) = parseListingsOptions options
  let language = case lookup "language" options >>= fromListingsLanguage of
                      Just l -> [l]
                      Nothing -> take 1 $ languagesByExtension (takeExtension f)
  let firstline = fromMaybe 1 $ lookup "firstline" options >>= safeRead
  let lastline = fromMaybe (length codeLines) $
                       lookup "lastline" options >>= safeRead
  let codeContents = intercalate "\n" $ take (1 + lastline - firstline) $
                       drop (firstline - 1) codeLines
  return $ codeBlockWith (ident,ordNub (classes ++ language),kvs) codeContents

-- lists

item :: PandocMonad m => LP m Blocks
item = void blocks *> controlSeq "item" *> skipopts *> blocks

descItem :: PandocMonad m => LP m (Inlines, [Blocks])
descItem = do
  blocks -- skip blocks before item
  controlSeq "item"
  optional sp
  ils <- opt
  bs <- blocks
  return (ils, [bs])

listenv :: PandocMonad m => Text -> LP m a -> LP m a
listenv name p = try $ do
  oldInListItem <- sInListItem `fmap` getState
  updateState $ \st -> st{ sInListItem = True }
  res <- env name p
  updateState $ \st -> st{ sInListItem = oldInListItem }
  return res

orderedList' :: PandocMonad m => LP m Blocks
orderedList' = try $ do
  spaces
  let markerSpec = do
        symbol '['
        ts <- toksToString <$> manyTill anyTok (symbol ']')
        case runParser anyOrderedListMarker def "option" ts of
             Right r -> return r
             Left _  -> do
               pos <- getPosition
               report $ SkippedContent ("[" ++ ts ++ "]") pos
               return (1, DefaultStyle, DefaultDelim)
  (_, style, delim) <- option (1, DefaultStyle, DefaultDelim) markerSpec
  spaces
  optional $ try $ controlSeq "setlength"
                   *> grouped (count 1 $ controlSeq "itemindent")
                   *> braced
  spaces
  start <- option 1 $ try $ do pos <- getPosition
                               controlSeq "setcounter"
                               ctr <- toksToString <$> braced
                               guard $ "enum" `isPrefixOf` ctr
                               guard $ all (`elem` ['i','v']) (drop 4 ctr)
                               optional sp
                               num <- toksToString <$> braced
                               case safeRead num of
                                    Just i -> return (i + 1 :: Int)
                                    Nothing -> do
                                      report $ SkippedContent
                                        ("\\setcounter{" ++ ctr ++
                                         "}{" ++ num ++ "}") pos
                                      return 1
  bs <- listenv "enumerate" (many item)
  return $ orderedListWith (start, style, delim) bs

-- tables

hline :: PandocMonad m => LP m ()
hline = try $ do
  spaces
  controlSeq "hline" <|>
    -- booktabs rules:
    controlSeq "toprule" <|>
    controlSeq "bottomrule" <|>
    controlSeq "midrule" <|>
    controlSeq "endhead" <|>
    controlSeq "endfirsthead"
  spaces
  optional opt
  return ()

lbreak :: PandocMonad m => LP m Tok
lbreak = (controlSeq "\\" <|> controlSeq "tabularnewline") <* spaces

amp :: PandocMonad m => LP m Tok
amp = symbol '&'

-- Split a Word into individual Symbols (for parseAligns)
splitWordTok :: PandocMonad m => LP m ()
splitWordTok = do
  inp <- getInput
  case inp of
       (Tok spos Word t : rest) ->
         setInput $ map (Tok spos Symbol . T.singleton) (T.unpack t) ++ rest
       _ -> return ()

parseAligns :: PandocMonad m => LP m [(Alignment, Double, ([Tok], [Tok]))]
parseAligns = try $ do
  let maybeBar = skipMany $
        sp <|> () <$ symbol '|' <|> () <$ (symbol '@' >> braced)
  let cAlign = AlignCenter <$ symbol 'c'
  let lAlign = AlignLeft <$ symbol 'l'
  let rAlign = AlignRight <$ symbol 'r'
  let parAlign = AlignLeft <$ symbol 'p'
  -- aligns from tabularx
  let xAlign = AlignLeft <$ symbol 'X'
  let mAlign = AlignLeft <$ symbol 'm'
  let bAlign = AlignLeft <$ symbol 'b'
  let alignChar = splitWordTok *> (  cAlign <|> lAlign <|> rAlign <|> parAlign
                                 <|> xAlign <|> mAlign <|> bAlign )
  let alignPrefix = symbol '>' >> braced
  let alignSuffix = symbol '<' >> braced
  let colWidth = try $ do
        symbol '{'
        ds <- trim . toksToString <$> manyTill anyTok (controlSeq "linewidth")
        spaces
        symbol '}'
        case safeRead ds of
              Just w  -> return w
              Nothing -> return 0.0
  let alignSpec = do
        pref <- option [] alignPrefix
        spaces
        al <- alignChar
        width <- colWidth <|> option 0.0 (do s <- toksToString <$> braced
                                             pos <- getPosition
                                             report $ SkippedContent s pos
                                             return 0.0)
        spaces
        suff <- option [] alignSuffix
        return (al, width, (pref, suff))
  let starAlign = do -- '*{2}{r}' == 'rr', we just expand like a macro
        symbol '*'
        spaces
        ds <- trim . toksToString <$> braced
        spaces
        spec <- braced
        case safeRead ds of
             Just n  ->
               getInput >>= setInput . (mconcat (replicate n spec) ++)
             Nothing -> fail $ "Could not parse " ++ ds ++ " as number"
  bgroup
  spaces
  maybeBar
  aligns' <- many $ try $ spaces >> optional starAlign >>
                            (alignSpec <* maybeBar)
  spaces
  egroup
  spaces
  return aligns'

parseTableRow :: PandocMonad m
              => Text   -- ^ table environment name
              -> [([Tok], [Tok])] -- ^ pref/suffixes
              -> LP m [Blocks]
parseTableRow envname prefsufs = do
  notFollowedBy (spaces *> end_ envname)
  let cols = length prefsufs
  -- add prefixes and suffixes in token stream:
  let celltoks (pref, suff) = do
        prefpos <- getPosition
        contents <- many (notFollowedBy
                         (() <$ amp <|> () <$ lbreak <|> end_ envname)
                         >> anyTok)
        suffpos <- getPosition
        option [] (count 1 amp)
        return $ map (setpos prefpos) pref ++ contents ++ map (setpos suffpos) suff
  rawcells <- mapM celltoks prefsufs
  oldInput <- getInput
  cells <- mapM (\ts -> setInput ts >> parseTableCell) rawcells
  setInput oldInput
  spaces
  let numcells = length cells
  guard $ numcells <= cols && numcells >= 1
  guard $ cells /= [mempty]
  -- note:  a & b in a three-column table leaves an empty 3rd cell:
  return $ cells ++ replicate (cols - numcells) mempty

parseTableCell :: PandocMonad m => LP m Blocks
parseTableCell = do
  let plainify bs = case toList bs of
                         [Para ils] -> plain (fromList ils)
                         _          -> bs
  updateState $ \st -> st{ sInTableCell = True }
  cells <- plainify <$> blocks
  updateState $ \st -> st{ sInTableCell = False }
  return cells

simpTable :: PandocMonad m => Text -> Bool -> LP m Blocks
simpTable envname hasWidthParameter = try $ do
  when hasWidthParameter $ () <$ (spaces >> tok)
  skipopts
  colspecs <- parseAligns
  let (aligns, widths, prefsufs) = unzip3 colspecs
  let cols = length colspecs
  optional $ controlSeq "caption" *> skipopts *> setCaption
  optional lbreak
  spaces
  skipMany hline
  spaces
  header' <- option [] $ try (parseTableRow envname prefsufs <*
                                   lbreak <* many1 hline)
  spaces
  rows <- sepEndBy (parseTableRow envname prefsufs)
                    (lbreak <* optional (skipMany hline))
  spaces
  optional $ controlSeq "caption" *> skipopts *> setCaption
  optional lbreak
  spaces
  let header'' = if null header'
                    then replicate cols mempty
                    else header'
  lookAhead $ controlSeq "end" -- make sure we're at end
  return $ table mempty (zip aligns widths) header'' rows

addTableCaption :: PandocMonad m => Blocks -> LP m Blocks
addTableCaption = walkM go
  where go (Table c als ws hs rs) = do
          (mbcapt, _) <- sCaption <$> getState
          return $ case mbcapt of
               Just ils -> Table (toList ils) als ws hs rs
               Nothing  -> Table c als ws hs rs
        go x = return x


block :: PandocMonad m => LP m Blocks
block = do
  res <- (mempty <$ spaces1)
    <|> environment
    <|> macroDef
    <|> blockCommand
    <|> paragraph
    <|> grouped block
  trace (take 60 $ show $ B.toList res)
  return res

blocks :: PandocMonad m => LP m Blocks
blocks = mconcat <$> many block

setDefaultLanguage :: PandocMonad m => LP m Blocks
setDefaultLanguage = do
  o <- option "" $ (T.unpack . T.filter (\c -> c /= '[' && c /= ']'))
                <$> rawopt
  polylang <- toksToString <$> braced
  case M.lookup polylang polyglossiaLangToBCP47 of
       Nothing -> return mempty -- TODO mzero? warning?
       Just langFunc -> do
         let l = langFunc o
         setTranslations l
         updateState $ setMeta "lang" $ str (renderLang l)
         return mempty

polyglossiaLangToBCP47 :: M.Map String (String -> Lang)
polyglossiaLangToBCP47 = M.fromList
  [ ("arabic", \o -> case filter (/=' ') o of
       "locale=algeria"    -> Lang "ar" "" "DZ" []
       "locale=mashriq"    -> Lang "ar" "" "SY" []
       "locale=libya"      -> Lang "ar" "" "LY" []
       "locale=morocco"    -> Lang "ar" "" "MA" []
       "locale=mauritania" -> Lang "ar" "" "MR" []
       "locale=tunisia"    -> Lang "ar" "" "TN" []
       _                   -> Lang "ar" "" "" [])
  , ("german", \o -> case filter (/=' ') o of
       "spelling=old" -> Lang "de" "" "DE" ["1901"]
       "variant=austrian,spelling=old"
                       -> Lang "de" "" "AT" ["1901"]
       "variant=austrian" -> Lang "de" "" "AT" []
       "variant=swiss,spelling=old"
                       -> Lang "de" "" "CH" ["1901"]
       "variant=swiss" -> Lang "de" "" "CH" []
       _ -> Lang "de" "" "" [])
  , ("lsorbian", \_ -> Lang "dsb" "" "" [])
  , ("greek", \o -> case filter (/=' ') o of
       "variant=poly"    -> Lang "el" "" "polyton" []
       "variant=ancient" -> Lang "grc" "" "" []
       _                 -> Lang "el" "" "" [])
  , ("english", \o -> case filter (/=' ') o of
       "variant=australian" -> Lang "en" "" "AU" []
       "variant=canadian"   -> Lang "en" "" "CA" []
       "variant=british"    -> Lang "en" "" "GB" []
       "variant=newzealand" -> Lang "en" "" "NZ" []
       "variant=american"   -> Lang "en" "" "US" []
       _                    -> Lang "en" "" "" [])
  , ("usorbian", \_ -> Lang "hsb" "" "" [])
  , ("latin", \o -> case filter (/=' ') o of
       "variant=classic" -> Lang "la" "" "" ["x-classic"]
       _                 -> Lang "la" "" "" [])
  , ("slovenian", \_ -> Lang "sl" "" "" [])
  , ("serbianc", \_ -> Lang "sr" "cyrl" "" [])
  , ("pinyin", \_ -> Lang "zh" "Latn" "" ["pinyin"])
  , ("afrikaans", \_ -> Lang "af" "" "" [])
  , ("amharic", \_ -> Lang "am" "" "" [])
  , ("assamese", \_ -> Lang "as" "" "" [])
  , ("asturian", \_ -> Lang "ast" "" "" [])
  , ("bulgarian", \_ -> Lang "bg" "" "" [])
  , ("bengali", \_ -> Lang "bn" "" "" [])
  , ("tibetan", \_ -> Lang "bo" "" "" [])
  , ("breton", \_ -> Lang "br" "" "" [])
  , ("catalan", \_ -> Lang "ca" "" "" [])
  , ("welsh", \_ -> Lang "cy" "" "" [])
  , ("czech", \_ -> Lang "cs" "" "" [])
  , ("coptic", \_ -> Lang "cop" "" "" [])
  , ("danish", \_ -> Lang "da" "" "" [])
  , ("divehi", \_ -> Lang "dv" "" "" [])
  , ("esperanto", \_ -> Lang "eo" "" "" [])
  , ("spanish", \_ -> Lang "es" "" "" [])
  , ("estonian", \_ -> Lang "et" "" "" [])
  , ("basque", \_ -> Lang "eu" "" "" [])
  , ("farsi", \_ -> Lang "fa" "" "" [])
  , ("finnish", \_ -> Lang "fi" "" "" [])
  , ("french", \_ -> Lang "fr" "" "" [])
  , ("friulan", \_ -> Lang "fur" "" "" [])
  , ("irish", \_ -> Lang "ga" "" "" [])
  , ("scottish", \_ -> Lang "gd" "" "" [])
  , ("ethiopic", \_ -> Lang "gez" "" "" [])
  , ("galician", \_ -> Lang "gl" "" "" [])
  , ("hebrew", \_ -> Lang "he" "" "" [])
  , ("hindi", \_ -> Lang "hi" "" "" [])
  , ("croatian", \_ -> Lang "hr" "" "" [])
  , ("magyar", \_ -> Lang "hu" "" "" [])
  , ("armenian", \_ -> Lang "hy" "" "" [])
  , ("interlingua", \_ -> Lang "ia" "" "" [])
  , ("indonesian", \_ -> Lang "id" "" "" [])
  , ("icelandic", \_ -> Lang "is" "" "" [])
  , ("italian", \_ -> Lang "it" "" "" [])
  , ("japanese", \_ -> Lang "jp" "" "" [])
  , ("khmer", \_ -> Lang "km" "" "" [])
  , ("kurmanji", \_ -> Lang "kmr" "" "" [])
  , ("kannada", \_ -> Lang "kn" "" "" [])
  , ("korean", \_ -> Lang "ko" "" "" [])
  , ("lao", \_ -> Lang "lo" "" "" [])
  , ("lithuanian", \_ -> Lang "lt" "" "" [])
  , ("latvian", \_ -> Lang "lv" "" "" [])
  , ("malayalam", \_ -> Lang "ml" "" "" [])
  , ("mongolian", \_ -> Lang "mn" "" "" [])
  , ("marathi", \_ -> Lang "mr" "" "" [])
  , ("dutch", \_ -> Lang "nl" "" "" [])
  , ("nynorsk", \_ -> Lang "nn" "" "" [])
  , ("norsk", \_ -> Lang "no" "" "" [])
  , ("nko", \_ -> Lang "nqo" "" "" [])
  , ("occitan", \_ -> Lang "oc" "" "" [])
  , ("panjabi", \_ -> Lang "pa" "" "" [])
  , ("polish", \_ -> Lang "pl" "" "" [])
  , ("piedmontese", \_ -> Lang "pms" "" "" [])
  , ("portuguese", \_ -> Lang "pt" "" "" [])
  , ("romansh", \_ -> Lang "rm" "" "" [])
  , ("romanian", \_ -> Lang "ro" "" "" [])
  , ("russian", \_ -> Lang "ru" "" "" [])
  , ("sanskrit", \_ -> Lang "sa" "" "" [])
  , ("samin", \_ -> Lang "se" "" "" [])
  , ("slovak", \_ -> Lang "sk" "" "" [])
  , ("albanian", \_ -> Lang "sq" "" "" [])
  , ("serbian", \_ -> Lang "sr" "" "" [])
  , ("swedish", \_ -> Lang "sv" "" "" [])
  , ("syriac", \_ -> Lang "syr" "" "" [])
  , ("tamil", \_ -> Lang "ta" "" "" [])
  , ("telugu", \_ -> Lang "te" "" "" [])
  , ("thai", \_ -> Lang "th" "" "" [])
  , ("turkmen", \_ -> Lang "tk" "" "" [])
  , ("turkish", \_ -> Lang "tr" "" "" [])
  , ("ukrainian", \_ -> Lang "uk" "" "" [])
  , ("urdu", \_ -> Lang "ur" "" "" [])
  , ("vietnamese", \_ -> Lang "vi" "" "" [])
  ]

babelLangToBCP47 :: String -> Maybe Lang
babelLangToBCP47 s =
  case s of
       "austrian" -> Just $ Lang "de" "" "AT" ["1901"]
       "naustrian" -> Just $ Lang "de" "" "AT" []
       "swissgerman" -> Just $ Lang "de" "" "CH" ["1901"]
       "nswissgerman" -> Just $ Lang "de" "" "CH" []
       "german" -> Just $ Lang "de" "" "DE" ["1901"]
       "ngerman" -> Just $ Lang "de" "" "DE" []
       "lowersorbian" -> Just $ Lang "dsb" "" "" []
       "uppersorbian" -> Just $ Lang "hsb" "" "" []
       "polutonikogreek" -> Just $ Lang "el" "" "" ["polyton"]
       "slovene" -> Just $ Lang "sl" "" "" []
       "australian" -> Just $ Lang "en" "" "AU" []
       "canadian" -> Just $ Lang "en" "" "CA" []
       "british" -> Just $ Lang "en" "" "GB" []
       "newzealand" -> Just $ Lang "en" "" "NZ" []
       "american" -> Just $ Lang "en" "" "US" []
       "classiclatin" -> Just $ Lang "la" "" "" ["x-classic"]
       _ -> fmap ($ "") $ M.lookup s polyglossiaLangToBCP47