pandoc/src/Text/Pandoc/Readers/MediaWiki.hs
John MacFarlane 2363e6a15b Move CR filtering from tabFilter to the readers.
The readers previously assumed that CRs had been filtered
from the input.  Now we strip the CRs in the readers themselves,
before parsing.  (The point of this is just to simplify the
parsers.)

Shared now exports a new function `crFilter`. [API change]
And `tabFilter` no longer filters CRs.
2017-06-20 21:52:13 +02:00

705 lines
25 KiB
Haskell

{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE RelaxedPolyRec #-}
{-# LANGUAGE TypeSynonymInstances #-}
-- RelaxedPolyRec needed for inlinesBetween on GHC < 7
{-
Copyright (C) 2012-2017 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.MediaWiki
Copyright : Copyright (C) 2012-2017 John MacFarlane
License : GNU GPL, version 2 or above
Maintainer : John MacFarlane <jgm@berkeley.edu>
Stability : alpha
Portability : portable
Conversion of mediawiki text to 'Pandoc' document.
-}
{-
TODO:
_ correctly handle tables within tables
_ parse templates?
-}
module Text.Pandoc.Readers.MediaWiki ( readMediaWiki ) where
import Control.Monad
import Control.Monad.Except (throwError)
import Data.Char (isDigit, isSpace)
import Data.Text (Text, unpack)
import qualified Data.Foldable as F
import Data.List (intercalate, intersperse, isPrefixOf)
import qualified Data.Map as M
import Data.Maybe (fromMaybe)
import Data.Monoid ((<>))
import Data.Sequence (ViewL (..), viewl, (<|))
import qualified Data.Set as Set
import Text.HTML.TagSoup
import Text.Pandoc.Builder (Blocks, Inlines, trimInlines)
import qualified Text.Pandoc.Builder as B
import Text.Pandoc.Class (PandocMonad(..))
import Text.Pandoc.Definition
import Text.Pandoc.Logging
import Text.Pandoc.Options
import Text.Pandoc.Parsing hiding (nested)
import Text.Pandoc.Readers.HTML (htmlTag, isBlockTag, isCommentTag)
import Text.Pandoc.Shared (safeRead, stringify, stripTrailingNewlines, trim,
crFilter)
import Text.Pandoc.Walk (walk)
import Text.Pandoc.XML (fromEntities)
-- | Read mediawiki from an input string and return a Pandoc document.
readMediaWiki :: PandocMonad m
=> ReaderOptions -- ^ Reader options
-> Text -- ^ String to parse (assuming @'\n'@ line endings)
-> m Pandoc
readMediaWiki opts s = do
parsed <- readWithM parseMediaWiki MWState{ mwOptions = opts
, mwMaxNestingLevel = 4
, mwNextLinkNumber = 1
, mwCategoryLinks = []
, mwHeaderMap = M.empty
, mwIdentifierList = Set.empty
, mwLogMessages = []
, mwInTT = False
}
(unpack (crFilter s) ++ "\n")
case parsed of
Right result -> return result
Left e -> throwError e
data MWState = MWState { mwOptions :: ReaderOptions
, mwMaxNestingLevel :: Int
, mwNextLinkNumber :: Int
, mwCategoryLinks :: [Inlines]
, mwHeaderMap :: M.Map Inlines String
, mwIdentifierList :: Set.Set String
, mwLogMessages :: [LogMessage]
, mwInTT :: Bool
}
type MWParser m = ParserT [Char] MWState m
instance HasReaderOptions MWState where
extractReaderOptions = mwOptions
instance HasHeaderMap MWState where
extractHeaderMap = mwHeaderMap
updateHeaderMap f st = st{ mwHeaderMap = f $ mwHeaderMap st }
instance HasIdentifierList MWState where
extractIdentifierList = mwIdentifierList
updateIdentifierList f st = st{ mwIdentifierList = f $ mwIdentifierList st }
instance HasLogMessages MWState where
addLogMessage m s = s{ mwLogMessages = m : mwLogMessages s }
getLogMessages = reverse . mwLogMessages
--
-- auxiliary functions
--
-- This is used to prevent exponential blowups for things like:
-- ''a'''a''a'''a''a'''a''a'''a
nested :: PandocMonad m => MWParser m a -> MWParser m a
nested p = do
nestlevel <- mwMaxNestingLevel `fmap` getState
guard $ nestlevel > 0
updateState $ \st -> st{ mwMaxNestingLevel = mwMaxNestingLevel st - 1 }
res <- p
updateState $ \st -> st{ mwMaxNestingLevel = nestlevel }
return res
specialChars :: [Char]
specialChars = "'[]<=&*{}|\":\\"
spaceChars :: [Char]
spaceChars = " \n\t"
sym :: PandocMonad m => String -> MWParser m ()
sym s = () <$ try (string s)
newBlockTags :: [String]
newBlockTags = ["haskell","syntaxhighlight","source","gallery","references"]
isBlockTag' :: Tag String -> Bool
isBlockTag' tag@(TagOpen t _) = (isBlockTag tag || t `elem` newBlockTags) &&
t `notElem` eitherBlockOrInline
isBlockTag' tag@(TagClose t) = (isBlockTag tag || t `elem` newBlockTags) &&
t `notElem` eitherBlockOrInline
isBlockTag' tag = isBlockTag tag
isInlineTag' :: Tag String -> Bool
isInlineTag' (TagComment _) = True
isInlineTag' t = not (isBlockTag' t)
eitherBlockOrInline :: [String]
eitherBlockOrInline = ["applet", "button", "del", "iframe", "ins",
"map", "area", "object"]
htmlComment :: PandocMonad m => MWParser m ()
htmlComment = () <$ htmlTag isCommentTag
inlinesInTags :: PandocMonad m => String -> MWParser m Inlines
inlinesInTags tag = try $ do
(_,raw) <- htmlTag (~== TagOpen tag [])
if '/' `elem` raw -- self-closing tag
then return mempty
else trimInlines . mconcat <$>
manyTill inline (htmlTag (~== TagClose tag))
blocksInTags :: PandocMonad m => String -> MWParser m Blocks
blocksInTags tag = try $ do
(_,raw) <- htmlTag (~== TagOpen tag [])
let closer = if tag == "li"
then htmlTag (~== TagClose "li")
<|> lookAhead (
htmlTag (~== TagOpen "li" [])
<|> htmlTag (~== TagClose "ol")
<|> htmlTag (~== TagClose "ul"))
else htmlTag (~== TagClose tag)
if '/' `elem` raw -- self-closing tag
then return mempty
else mconcat <$> manyTill block closer
charsInTags :: PandocMonad m => String -> MWParser m [Char]
charsInTags tag = try $ do
(_,raw) <- htmlTag (~== TagOpen tag [])
if '/' `elem` raw -- self-closing tag
then return ""
else manyTill anyChar (htmlTag (~== TagClose tag))
--
-- main parser
--
parseMediaWiki :: PandocMonad m => MWParser m Pandoc
parseMediaWiki = do
bs <- mconcat <$> many block
spaces
eof
categoryLinks <- reverse . mwCategoryLinks <$> getState
let categories = if null categoryLinks
then mempty
else B.para $ mconcat $ intersperse B.space categoryLinks
reportLogMessages
return $ B.doc $ bs <> categories
--
-- block parsers
--
block :: PandocMonad m => MWParser m Blocks
block = do
res <- mempty <$ skipMany1 blankline
<|> table
<|> header
<|> hrule
<|> orderedList
<|> bulletList
<|> definitionList
<|> mempty <$ try (spaces *> htmlComment)
<|> preformatted
<|> blockTag
<|> (B.rawBlock "mediawiki" <$> template)
<|> para
trace (take 60 $ show $ B.toList res)
return res
para :: PandocMonad m => MWParser m Blocks
para = do
contents <- trimInlines . mconcat <$> many1 inline
if F.all (==Space) contents
then return mempty
else return $ B.para contents
table :: PandocMonad m => MWParser m Blocks
table = do
tableStart
styles <- option [] parseAttrs
skipMany spaceChar
optional blanklines
let tableWidth = case lookup "width" styles of
Just w -> fromMaybe 1.0 $ parseWidth w
Nothing -> 1.0
caption <- option mempty tableCaption
optional rowsep
hasheader <- option False $ True <$ (lookAhead (skipSpaces *> char '!'))
(cellspecs',hdr) <- unzip <$> tableRow
let widths = map ((tableWidth *) . snd) cellspecs'
let restwidth = tableWidth - sum widths
let zerocols = length $ filter (==0.0) widths
let defaultwidth = if zerocols == 0 || zerocols == length widths
then 0.0
else restwidth / fromIntegral zerocols
let widths' = map (\w -> if w == 0 then defaultwidth else w) widths
let cellspecs = zip (map fst cellspecs') widths'
rows' <- many $ try $ rowsep *> (map snd <$> tableRow)
optional blanklines
tableEnd
let cols = length hdr
let (headers,rows) = if hasheader
then (hdr, rows')
else (replicate cols mempty, hdr:rows')
return $ B.table caption cellspecs headers rows
parseAttrs :: PandocMonad m => MWParser m [(String,String)]
parseAttrs = many1 parseAttr
parseAttr :: PandocMonad m => MWParser m (String, String)
parseAttr = try $ do
skipMany spaceChar
k <- many1 letter
char '='
v <- (char '"' >> many1Till (satisfy (/='\n')) (char '"'))
<|> many1 (satisfy $ \c -> not (isSpace c) && c /= '|')
return (k,v)
tableStart :: PandocMonad m => MWParser m ()
tableStart = try $ guardColumnOne *> skipSpaces *> sym "{|"
tableEnd :: PandocMonad m => MWParser m ()
tableEnd = try $ guardColumnOne *> skipSpaces *> sym "|}"
rowsep :: PandocMonad m => MWParser m ()
rowsep = try $ guardColumnOne *> skipSpaces *> sym "|-" <*
many (char '-') <* optional parseAttr <* blanklines
cellsep :: PandocMonad m => MWParser m ()
cellsep = try $ do
skipSpaces
(char '|' *> notFollowedBy (oneOf "-}+") *> optional (char '|'))
<|> (char '!' *> optional (char '!'))
tableCaption :: PandocMonad m => MWParser m Inlines
tableCaption = try $ do
guardColumnOne
skipSpaces
sym "|+"
optional (try $ parseAttr *> skipSpaces *> char '|' *> skipSpaces)
(trimInlines . mconcat) <$> many (notFollowedBy (cellsep <|> rowsep) *> inline)
tableRow :: PandocMonad m => MWParser m [((Alignment, Double), Blocks)]
tableRow = try $ skipMany htmlComment *> many tableCell
tableCell :: PandocMonad m => MWParser m ((Alignment, Double), Blocks)
tableCell = try $ do
cellsep
skipMany spaceChar
attrs <- option [] $ try $ parseAttrs <* skipSpaces <* char '|' <*
notFollowedBy (char '|')
skipMany spaceChar
pos' <- getPosition
ls <- concat <$> many (notFollowedBy (cellsep <|> rowsep <|> tableEnd) *>
((snd <$> withRaw table) <|> count 1 anyChar))
bs <- parseFromString (do setPosition pos'
mconcat <$> many block) ls
let align = case lookup "align" attrs of
Just "left" -> AlignLeft
Just "right" -> AlignRight
Just "center" -> AlignCenter
_ -> AlignDefault
let width = case lookup "width" attrs of
Just xs -> fromMaybe 0.0 $ parseWidth xs
Nothing -> 0.0
return ((align, width), bs)
parseWidth :: String -> Maybe Double
parseWidth s =
case reverse s of
('%':ds) | all isDigit ds -> safeRead ('0':'.':reverse ds)
_ -> Nothing
template :: PandocMonad m => MWParser m String
template = try $ do
string "{{"
notFollowedBy (char '{')
lookAhead $ letter <|> digit <|> char ':'
let chunk = template <|> variable <|> many1 (noneOf "{}") <|> count 1 anyChar
contents <- manyTill chunk (try $ string "}}")
return $ "{{" ++ concat contents ++ "}}"
blockTag :: PandocMonad m => MWParser m Blocks
blockTag = do
(tag, _) <- lookAhead $ htmlTag isBlockTag'
case tag of
TagOpen "blockquote" _ -> B.blockQuote <$> blocksInTags "blockquote"
TagOpen "pre" _ -> B.codeBlock . trimCode <$> charsInTags "pre"
TagOpen "syntaxhighlight" attrs -> syntaxhighlight "syntaxhighlight" attrs
TagOpen "source" attrs -> syntaxhighlight "source" attrs
TagOpen "haskell" _ -> B.codeBlockWith ("",["haskell"],[]) . trimCode <$>
charsInTags "haskell"
TagOpen "gallery" _ -> blocksInTags "gallery"
TagOpen "p" _ -> mempty <$ htmlTag (~== tag)
TagClose "p" -> mempty <$ htmlTag (~== tag)
_ -> B.rawBlock "html" . snd <$> htmlTag (~== tag)
trimCode :: String -> String
trimCode ('\n':xs) = stripTrailingNewlines xs
trimCode xs = stripTrailingNewlines xs
syntaxhighlight :: PandocMonad m => String -> [Attribute String] -> MWParser m Blocks
syntaxhighlight tag attrs = try $ do
let mblang = lookup "lang" attrs
let mbstart = lookup "start" attrs
let mbline = lookup "line" attrs
let classes = maybe [] (:[]) mblang ++ maybe [] (const ["numberLines"]) mbline
let kvs = maybe [] (\x -> [("startFrom",x)]) mbstart
contents <- charsInTags tag
return $ B.codeBlockWith ("",classes,kvs) $ trimCode contents
hrule :: PandocMonad m => MWParser m Blocks
hrule = B.horizontalRule <$ try (string "----" *> many (char '-') *> newline)
guardColumnOne :: PandocMonad m => MWParser m ()
guardColumnOne = getPosition >>= \pos -> guard (sourceColumn pos == 1)
preformatted :: PandocMonad m => MWParser m Blocks
preformatted = try $ do
guardColumnOne
char ' '
let endline' = B.linebreak <$ (try $ newline <* char ' ')
let whitespace' = B.str <$> many1 ('\160' <$ spaceChar)
let spToNbsp ' ' = '\160'
spToNbsp x = x
let nowiki' = mconcat . intersperse B.linebreak . map B.str .
lines . fromEntities . map spToNbsp <$> try
(htmlTag (~== TagOpen "nowiki" []) *>
manyTill anyChar (htmlTag (~== TagClose "nowiki")))
let inline' = whitespace' <|> endline' <|> nowiki'
<|> (try $ notFollowedBy newline *> inline)
contents <- mconcat <$> many1 inline'
let spacesStr (Str xs) = all isSpace xs
spacesStr _ = False
if F.all spacesStr contents
then return mempty
else return $ B.para $ encode contents
encode :: Inlines -> Inlines
encode = B.fromList . normalizeCode . B.toList . walk strToCode
where strToCode (Str s) = Code ("",[],[]) s
strToCode Space = Code ("",[],[]) " "
strToCode x = x
normalizeCode [] = []
normalizeCode (Code a1 x : Code a2 y : zs) | a1 == a2 =
normalizeCode $ (Code a1 (x ++ y)) : zs
normalizeCode (x:xs) = x : normalizeCode xs
header :: PandocMonad m => MWParser m Blocks
header = try $ do
guardColumnOne
eqs <- many1 (char '=')
let lev = length eqs
guard $ lev <= 6
contents <- trimInlines . mconcat <$> manyTill inline (count lev $ char '=')
attr <- registerHeader nullAttr contents
return $ B.headerWith attr lev contents
bulletList :: PandocMonad m => MWParser m Blocks
bulletList = B.bulletList <$>
( many1 (listItem '*')
<|> (htmlTag (~== TagOpen "ul" []) *> spaces *> many (listItem '*' <|> li) <*
optional (htmlTag (~== TagClose "ul"))) )
orderedList :: PandocMonad m => MWParser m Blocks
orderedList =
(B.orderedList <$> many1 (listItem '#'))
<|> try
(do (tag,_) <- htmlTag (~== TagOpen "ol" [])
spaces
items <- many (listItem '#' <|> li)
optional (htmlTag (~== TagClose "ol"))
let start = fromMaybe 1 $ safeRead $ fromAttrib "start" tag
return $ B.orderedListWith (start, DefaultStyle, DefaultDelim) items)
definitionList :: PandocMonad m => MWParser m Blocks
definitionList = B.definitionList <$> many1 defListItem
defListItem :: PandocMonad m => MWParser m (Inlines, [Blocks])
defListItem = try $ do
terms <- mconcat . intersperse B.linebreak <$> many defListTerm
-- we allow dd with no dt, or dt with no dd
defs <- if B.isNull terms
then notFollowedBy
(try $ skipMany1 (char ':') >> string "<math>") *>
many1 (listItem ':')
else many (listItem ':')
return (terms, defs)
defListTerm :: PandocMonad m => MWParser m Inlines
defListTerm = do
guardColumnOne
char ';'
skipMany spaceChar
pos' <- getPosition
anyLine >>= parseFromString (do setPosition pos'
trimInlines . mconcat <$> many inline)
listStart :: PandocMonad m => Char -> MWParser m ()
listStart c = char c *> notFollowedBy listStartChar
listStartChar :: PandocMonad m => MWParser m Char
listStartChar = oneOf "*#;:"
anyListStart :: PandocMonad m => MWParser m Char
anyListStart = guardColumnOne >> oneOf "*#:;"
li :: PandocMonad m => MWParser m Blocks
li = lookAhead (htmlTag (~== TagOpen "li" [])) *>
(firstParaToPlain <$> blocksInTags "li") <* spaces
listItem :: PandocMonad m => Char -> MWParser m Blocks
listItem c = try $ do
guardColumnOne
extras <- many (try $ char c <* lookAhead listStartChar)
if null extras
then listItem' c
else do
skipMany spaceChar
pos' <- getPosition
first <- concat <$> manyTill listChunk newline
rest <- many
(try $ string extras *> lookAhead listStartChar *>
(concat <$> manyTill listChunk newline))
contents <- parseFromString (do setPosition pos'
many1 $ listItem' c)
(unlines (first : rest))
case c of
'*' -> return $ B.bulletList contents
'#' -> return $ B.orderedList contents
':' -> return $ B.definitionList [(mempty, contents)]
_ -> mzero
-- The point of this is to handle stuff like
-- * {{cite book
-- | blah
-- | blah
-- }}
-- * next list item
-- which seems to be valid mediawiki.
listChunk :: PandocMonad m => MWParser m String
listChunk = template <|> count 1 anyChar
listItem' :: PandocMonad m => Char -> MWParser m Blocks
listItem' c = try $ do
listStart c
skipMany spaceChar
pos' <- getPosition
first <- concat <$> manyTill listChunk newline
rest <- many (try $ char c *> lookAhead listStartChar *>
(concat <$> manyTill listChunk newline))
parseFromString (do setPosition pos'
firstParaToPlain . mconcat <$> many1 block)
$ unlines $ first : rest
firstParaToPlain :: Blocks -> Blocks
firstParaToPlain contents =
case viewl (B.unMany contents) of
(Para xs) :< ys -> B.Many $ (Plain xs) <| ys
_ -> contents
--
-- inline parsers
--
inline :: PandocMonad m => MWParser m Inlines
inline = whitespace
<|> url
<|> str
<|> doubleQuotes
<|> strong
<|> emph
<|> image
<|> internalLink
<|> externalLink
<|> math
<|> inlineTag
<|> B.singleton <$> charRef
<|> inlineHtml
<|> (B.rawInline "mediawiki" <$> variable)
<|> (B.rawInline "mediawiki" <$> template)
<|> special
str :: PandocMonad m => MWParser m Inlines
str = B.str <$> many1 (noneOf $ specialChars ++ spaceChars)
math :: PandocMonad m => MWParser m Inlines
math = (B.displayMath . trim <$> try (many1 (char ':') >> charsInTags "math"))
<|> (B.math . trim <$> charsInTags "math")
<|> (B.displayMath . trim <$> try (dmStart *> manyTill anyChar dmEnd))
<|> (B.math . trim <$> try (mStart *> manyTill (satisfy (/='\n')) mEnd))
where dmStart = string "\\["
dmEnd = try (string "\\]")
mStart = string "\\("
mEnd = try (string "\\)")
variable :: PandocMonad m => MWParser m String
variable = try $ do
string "{{{"
contents <- manyTill anyChar (try $ string "}}}")
return $ "{{{" ++ contents ++ "}}}"
inlineTag :: PandocMonad m => MWParser m Inlines
inlineTag = do
(tag, _) <- lookAhead $ htmlTag isInlineTag'
case tag of
TagOpen "ref" _ -> B.note . B.plain <$> inlinesInTags "ref"
TagOpen "nowiki" _ -> try $ do
(_,raw) <- htmlTag (~== tag)
if '/' `elem` raw
then return mempty
else B.text . fromEntities <$>
manyTill anyChar (htmlTag (~== TagClose "nowiki"))
TagOpen "br" _ -> B.linebreak <$ (htmlTag (~== TagOpen "br" []) -- will get /> too
*> optional blankline)
TagOpen "strike" _ -> B.strikeout <$> inlinesInTags "strike"
TagOpen "del" _ -> B.strikeout <$> inlinesInTags "del"
TagOpen "sub" _ -> B.subscript <$> inlinesInTags "sub"
TagOpen "sup" _ -> B.superscript <$> inlinesInTags "sup"
TagOpen "code" _ -> encode <$> inlinesInTags "code"
TagOpen "tt" _ -> do
inTT <- mwInTT <$> getState
updateState $ \st -> st{ mwInTT = True }
result <- encode <$> inlinesInTags "tt"
updateState $ \st -> st{ mwInTT = inTT }
return result
TagOpen "hask" _ -> B.codeWith ("",["haskell"],[]) <$> charsInTags "hask"
_ -> B.rawInline "html" . snd <$> htmlTag (~== tag)
special :: PandocMonad m => MWParser m Inlines
special = B.str <$> count 1 (notFollowedBy' (htmlTag isBlockTag') *>
oneOf specialChars)
inlineHtml :: PandocMonad m => MWParser m Inlines
inlineHtml = B.rawInline "html" . snd <$> htmlTag isInlineTag'
whitespace :: PandocMonad m => MWParser m Inlines
whitespace = B.space <$ (skipMany1 spaceChar <|> htmlComment)
<|> B.softbreak <$ endline
endline :: PandocMonad m => MWParser m ()
endline = () <$ try (newline <*
notFollowedBy spaceChar <*
notFollowedBy newline <*
notFollowedBy' hrule <*
notFollowedBy tableStart <*
notFollowedBy' header <*
notFollowedBy anyListStart)
imageIdentifiers :: PandocMonad m => [MWParser m ()]
imageIdentifiers = [sym (identifier ++ ":") | identifier <- identifiers]
where identifiers = ["File", "Image", "Archivo", "Datei", "Fichier",
"Bild"]
image :: PandocMonad m => MWParser m Inlines
image = try $ do
sym "[["
choice imageIdentifiers
fname <- addUnderscores <$> many1 (noneOf "|]")
_ <- many imageOption
dims <- try (char '|' *> (sepBy (many digit) (char 'x')) <* string "px")
<|> return []
_ <- many imageOption
let kvs = case dims of
w:[] -> [("width", w)]
w:(h:[]) -> [("width", w), ("height", h)]
_ -> []
let attr = ("", [], kvs)
caption <- (B.str fname <$ sym "]]")
<|> try (char '|' *> (mconcat <$> manyTill inline (sym "]]")))
return $ B.imageWith attr fname ("fig:" ++ stringify caption) caption
imageOption :: PandocMonad m => MWParser m String
imageOption = try $ char '|' *> opt
where
opt = try (oneOfStrings [ "border", "thumbnail", "frameless"
, "thumb", "upright", "left", "right"
, "center", "none", "baseline", "sub"
, "super", "top", "text-top", "middle"
, "bottom", "text-bottom" ])
<|> try (string "frame")
<|> try (oneOfStrings ["link=","alt=","page=","class="] <* many (noneOf "|]"))
collapseUnderscores :: String -> String
collapseUnderscores [] = []
collapseUnderscores ('_':'_':xs) = collapseUnderscores ('_':xs)
collapseUnderscores (x:xs) = x : collapseUnderscores xs
addUnderscores :: String -> String
addUnderscores = collapseUnderscores . intercalate "_" . words
internalLink :: PandocMonad m => MWParser m Inlines
internalLink = try $ do
sym "[["
pagename <- unwords . words <$> many (noneOf "|]")
label <- option (B.text pagename) $ char '|' *>
( (mconcat <$> many1 (notFollowedBy (char ']') *> inline))
-- the "pipe trick"
-- [[Help:Contents|] -> "Contents"
<|> (return $ B.text $ drop 1 $ dropWhile (/=':') pagename) )
sym "]]"
linktrail <- B.text <$> many letter
let link = B.link (addUnderscores pagename) "wikilink" (label <> linktrail)
if "Category:" `isPrefixOf` pagename
then do
updateState $ \st -> st{ mwCategoryLinks = link : mwCategoryLinks st }
return mempty
else return link
externalLink :: PandocMonad m => MWParser m Inlines
externalLink = try $ do
char '['
(_, src) <- uri
lab <- try (trimInlines . mconcat <$>
(skipMany1 spaceChar *> manyTill inline (char ']')))
<|> do char ']'
num <- mwNextLinkNumber <$> getState
updateState $ \st -> st{ mwNextLinkNumber = num + 1 }
return $ B.str $ show num
return $ B.link src "" lab
url :: PandocMonad m => MWParser m Inlines
url = do
(orig, src) <- uri
return $ B.link src "" (B.str orig)
-- | Parses a list of inlines between start and end delimiters.
inlinesBetween :: (PandocMonad m, Show b) => MWParser m a -> MWParser m b -> MWParser m Inlines
inlinesBetween start end =
(trimInlines . mconcat) <$> try (start >> many1Till inner end)
where inner = innerSpace <|> (notFollowedBy' (() <$ whitespace) >> inline)
innerSpace = try $ whitespace <* notFollowedBy' end
emph :: PandocMonad m => MWParser m Inlines
emph = B.emph <$> nested (inlinesBetween start end)
where start = sym "''" >> lookAhead nonspaceChar
end = try $ notFollowedBy' (() <$ strong) >> sym "''"
strong :: PandocMonad m => MWParser m Inlines
strong = B.strong <$> nested (inlinesBetween start end)
where start = sym "'''" >> lookAhead nonspaceChar
end = try $ sym "'''"
doubleQuotes :: PandocMonad m => MWParser m Inlines
doubleQuotes = do
guardEnabled Ext_smart
inTT <- mwInTT <$> getState
guard (not inTT)
B.doubleQuoted <$> nested (inlinesBetween openDoubleQuote closeDoubleQuote)
where openDoubleQuote = sym "\"" >> lookAhead nonspaceChar
closeDoubleQuote = try $ sym "\""