From c3780992ab8e13944b69e5eab0e64884363ef1ad Mon Sep 17 00:00:00 2001 From: Alexander Sulfrian Date: Mon, 7 Jul 2014 20:21:38 +0200 Subject: TWiki Reader: add new new twiki reader --- src/Text/Pandoc/Readers/TWiki.hs | 526 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 526 insertions(+) create mode 100644 src/Text/Pandoc/Readers/TWiki.hs (limited to 'src/Text/Pandoc/Readers') diff --git a/src/Text/Pandoc/Readers/TWiki.hs b/src/Text/Pandoc/Readers/TWiki.hs new file mode 100644 index 000000000..c2325c0ea --- /dev/null +++ b/src/Text/Pandoc/Readers/TWiki.hs @@ -0,0 +1,526 @@ +{-# LANGUAGE RelaxedPolyRec, FlexibleInstances, TypeSynonymInstances #-} +-- RelaxedPolyRec needed for inlinesBetween on GHC < 7 +{- + Copyright (C) 2014 Alexander Sulfrian + +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.TWiki + Copyright : Copyright (C) 2014 Alexander Sulfrian + License : GNU GPL, version 2 or above + + Maintainer : Alexander Sulfrian + Stability : alpha + Portability : portable + +Conversion of twiki text to 'Pandoc' document. +-} +module Text.Pandoc.Readers.TWiki ( readTWiki + , readTWikiWithWarnings + ) where + +import Text.Pandoc.Definition +import qualified Text.Pandoc.Builder as B +import Text.Pandoc.Options +import Text.Pandoc.Parsing hiding (enclosed, macro, nested) +import Text.Pandoc.Readers.HTML (htmlTag, isCommentTag) +import Data.Monoid (Monoid, mconcat, mempty) +import Control.Applicative ((<$>), (<*), (*>), (<$)) +import Control.Monad +import Text.Printf (printf) +import Debug.Trace (trace) +import Text.Pandoc.XML (fromEntities) +import Data.Maybe (fromMaybe) +import Text.HTML.TagSoup +import Data.Char (isAlphaNum) +import qualified Data.Foldable as F + +-- | Read twiki from an input string and return a Pandoc document. +readTWiki :: ReaderOptions -- ^ Reader options + -> String -- ^ String to parse (assuming @'\n'@ line endings) + -> Pandoc +readTWiki opts s = + (readWith parseTWiki) def{ stateOptions = opts } (s ++ "\n\n") + +readTWikiWithWarnings :: ReaderOptions -- ^ Reader options + -> String -- ^ String to parse (assuming @'\n'@ line endings) + -> (Pandoc, [String]) +readTWikiWithWarnings opts s = + (readWith parseTWikiWithWarnings) def{ stateOptions = opts } (s ++ "\n\n") + where parseTWikiWithWarnings = do + doc <- parseTWiki + warnings <- stateWarnings <$> getState + return (doc, warnings) + +type TWParser = Parser [Char] ParserState + +-- +-- utility functions +-- + +tryMsg :: String -> TWParser a -> TWParser a +tryMsg msg p = try p msg + +skip :: TWParser a -> TWParser () +skip parser = parser >> return () + +nested :: TWParser a -> TWParser a +nested p = do + nestlevel <- stateMaxNestingLevel <$> getState + guard $ nestlevel > 0 + updateState $ \st -> st{ stateMaxNestingLevel = stateMaxNestingLevel st - 1 } + res <- p + updateState $ \st -> st{ stateMaxNestingLevel = nestlevel } + return res + +htmlElement :: String -> TWParser (Attr, String) +htmlElement tag = tryMsg tag $ do + (TagOpen _ attr, _) <- htmlTag (~== TagOpen tag []) + content <- manyTill anyChar (endtag <|> endofinput) + return (htmlAttrToPandoc attr, trim content) + where + endtag = skip $ htmlTag (~== TagClose tag) + endofinput = lookAhead $ try $ skipMany blankline >> skipSpaces >> eof + trim = dropWhile (=='\n') . reverse . dropWhile (=='\n') . reverse + +htmlAttrToPandoc :: [Attribute String] -> Attr +htmlAttrToPandoc attrs = (ident, classes, keyvals) + where + ident = fromMaybe "" $ lookup "id" attrs + classes = maybe [] words $ lookup "class" attrs + keyvals = [(k,v) | (k,v) <- attrs, k /= "id" && k /= "class"] + +parseHtmlContentWithAttrs :: String -> TWParser a -> TWParser (Attr, [a]) +parseHtmlContentWithAttrs tag parser = do + (attr, content) <- htmlElement tag + parsedContent <- try $ parseContent content + return (attr, parsedContent) + where + parseContent = parseFromString $ nested $ manyTill parser endOfContent + endOfContent = try $ skipMany blankline >> skipSpaces >> eof + +parseHtmlContent :: String -> TWParser a -> TWParser [a] +parseHtmlContent tag p = parseHtmlContentWithAttrs tag p >>= return . snd + +-- +-- main parser +-- + +parseTWiki :: TWParser Pandoc +parseTWiki = do + bs <- mconcat <$> many block + spaces + eof + return $ B.doc bs + + +-- +-- block parsers +-- + +block :: TWParser B.Blocks +block = do + tr <- getOption readerTrace + pos <- getPosition + res <- mempty <$ skipMany1 blankline + <|> blockElements + <|> para + skipMany blankline + when tr $ + trace (printf "line %d: %s" (sourceLine pos) + (take 60 $ show $ B.toList res)) (return ()) + return res + +blockElements :: TWParser B.Blocks +blockElements = choice [ separator + , header + , verbatim + , literal + , list "" + , table + , blockQuote + , noautolink + ] + +separator :: TWParser B.Blocks +separator = tryMsg "separator" $ string "---" >> newline >> return B.horizontalRule + +header :: TWParser B.Blocks +header = tryMsg "header" $ do + string "---" + level <- many1 (char '+') >>= return . length + guard $ level <= 6 + classes <- option [] $ string "!!" >> return ["unnumbered"] + skipSpaces + content <- B.trimInlines . mconcat <$> manyTill inline newline + attr <- registerHeader ("", classes, []) content + return $ B.headerWith attr level $ content + +verbatim :: TWParser B.Blocks +verbatim = (htmlElement "verbatim" <|> htmlElement "pre") + >>= return . (uncurry B.codeBlockWith) + +literal :: TWParser B.Blocks +literal = htmlElement "literal" >>= return . rawBlock + where + format (_, _, kvs) = fromMaybe "html" $ lookup "format" kvs + rawBlock (attrs, content) = B.rawBlock (format attrs) content + +list :: String -> TWParser B.Blocks +list prefix = choice [ bulletList prefix + , orderedList prefix + , definitionList prefix] + +definitionList :: String -> TWParser B.Blocks +definitionList prefix = tryMsg "definitionList" $ do + indent <- lookAhead $ string prefix *> (many1 $ string " ") <* string "$ " + elements <- many $ parseDefinitionListItem (prefix ++ concat indent) + return $ B.definitionList elements + where + parseDefinitionListItem :: String -> TWParser (B.Inlines, [B.Blocks]) + parseDefinitionListItem indent = do + string (indent ++ "$ ") >> skipSpaces + term <- many1Till inline $ string ": " + line <- listItemLine indent $ string "$ " + return $ (mconcat term, [line]) + +bulletList :: String -> TWParser B.Blocks +bulletList prefix = tryMsg "bulletList" $ + parseList prefix (char '*') (char ' ') + +orderedList :: String -> TWParser B.Blocks +orderedList prefix = tryMsg "orderedList" $ + parseList prefix (oneOf "1iIaA") (string ". ") + +parseList :: Show a => String -> TWParser Char -> TWParser a -> TWParser B.Blocks +parseList prefix marker delim = do + (indent, style) <- lookAhead $ string prefix *> listStyle <* delim + blocks <- many $ parseListItem (prefix ++ indent) (char style <* delim) + return $ case style of + '1' -> B.orderedListWith (1, DefaultStyle, DefaultDelim) blocks + 'i' -> B.orderedListWith (1, LowerRoman, DefaultDelim) blocks + 'I' -> B.orderedListWith (1, UpperRoman, DefaultDelim) blocks + 'a' -> B.orderedListWith (1, LowerAlpha, DefaultDelim) blocks + 'A' -> B.orderedListWith (1, UpperAlpha, DefaultDelim) blocks + _ -> B.bulletList blocks + where + listStyle = do + indent <- many1 $ string " " + style <- marker + return (concat indent, style) + +parseListItem :: Show a => String -> TWParser a -> TWParser B.Blocks +parseListItem prefix marker = string prefix >> marker >> listItemLine prefix marker + +listItemLine :: Show a => String -> TWParser a -> TWParser B.Blocks +listItemLine prefix marker = lineContent >>= parseContent >>= return . mconcat + where + lineContent = do + content <- anyLine + continuation <- optionMaybe listContinuation + return $ filterSpaces content ++ "\n" ++ (maybe "" (" " ++) continuation) + filterSpaces = reverse . dropWhile (== ' ') . reverse + listContinuation = notFollowedBy (string prefix >> marker) >> + string " " >> lineContent + parseContent = parseFromString $ many1 $ nestedList <|> parseInline + parseInline = many1Till inline (lastNewline <|> newlineBeforeNestedList) >>= + return . B.plain . mconcat + nestedList = list prefix + lastNewline = try $ char '\n' <* eof + newlineBeforeNestedList = try $ char '\n' <* lookAhead nestedList + +table :: TWParser B.Blocks +table = try $ do + tableHead <- optionMaybe $ many1Till tableParseHeader newline >>= return . unzip + rows <- many1 tableParseRow + return $ buildTable mempty rows $ fromMaybe (align rows, columns rows) tableHead + where + buildTable caption rows (aligns, heads) + = B.table caption aligns heads rows + align rows = replicate (columCount rows) (AlignDefault, 0) + columns rows = replicate (columCount rows) mempty + columCount rows = length $ head rows + +tableParseHeader :: TWParser ((Alignment, Double), B.Blocks) +tableParseHeader = try $ do + char '|' + leftSpaces <- many spaceChar >>= return . length + char '*' + content <- tableColumnContent (char '*' >> skipSpaces >> char '|') + char '*' + rightSpaces <- many spaceChar >>= return . length + optional tableEndOfRow + return (tableAlign leftSpaces rightSpaces, content) + where + tableAlign left right + | left >= 2 && left == right = (AlignCenter, 0) + | left > right = (AlignRight, 0) + | otherwise = (AlignLeft, 0) + +tableParseRow :: TWParser [B.Blocks] +tableParseRow = many1Till tableParseColumn newline + +tableParseColumn :: TWParser B.Blocks +tableParseColumn = char '|' *> skipSpaces *> + tableColumnContent (skipSpaces >> char '|') + <* skipSpaces <* optional tableEndOfRow + +tableEndOfRow :: TWParser Char +tableEndOfRow = lookAhead (try $ char '|' >> char '\n') >> char '|' + +tableColumnContent :: Show a => TWParser a -> TWParser B.Blocks +tableColumnContent end = manyTill content (lookAhead $ try end) >>= return . B.plain . mconcat + where + content = continuation <|> inline + continuation = try $ char '\\' >> newline >> return mempty + +blockQuote :: TWParser B.Blocks +blockQuote = parseHtmlContent "blockquote" block >>= return . B.blockQuote . mconcat + +noautolink :: TWParser B.Blocks +noautolink = do + (_, content) <- htmlElement "noautolink" + st <- getState + setState $ st{ stateAllowLinks = False } + blocks <- try $ parseContent content + setState $ st{ stateAllowLinks = True } + return $ mconcat blocks + where + parseContent = parseFromString $ many $ block + +para :: TWParser B.Blocks +para = many1Till inline endOfParaElement >>= return . result . mconcat + where + endOfParaElement = lookAhead $ endOfInput <|> endOfPara <|> newBlockElement + endOfInput = try $ skipMany blankline >> skipSpaces >> eof + endOfPara = try $ blankline >> skipMany1 blankline + newBlockElement = try $ blankline >> skip blockElements + result content = if F.all (==Space) content + then mempty + else B.para $ B.trimInlines content + + +-- +-- inline parsers +-- + +inline :: TWParser B.Inlines +inline = choice [ whitespace + , br + , macro + , strong + , strongHtml + , strongAndEmph + , emph + , emphHtml + , boldCode + , smart + , link + , htmlComment + , code + , codeHtml + , nop + , autoLink + , str + , symbol + ] "inline" + +whitespace :: TWParser B.Inlines +whitespace = (lb <|> regsp) >>= return + where lb = try $ skipMany spaceChar >> linebreak >> return B.space + regsp = try $ skipMany1 spaceChar >> return B.space + +br :: TWParser B.Inlines +br = try $ string "%BR%" >> return B.linebreak + +linebreak :: TWParser B.Inlines +linebreak = newline >> notFollowedBy newline >> (lastNewline <|> innerNewline) + where lastNewline = eof >> return mempty + innerNewline = return B.space + +between :: (Show b, Monoid c) => TWParser a -> TWParser b -> (TWParser b -> TWParser c) -> TWParser c +between start end p = + mconcat <$> try (start >> notFollowedBy whitespace >> many1Till (p end) end) + +enclosed :: (Show a, Monoid b) => TWParser a -> (TWParser a -> TWParser b) -> TWParser b +enclosed sep p = between sep (try $ sep <* endMarker) p + where + endMarker = lookAhead $ skip endSpace <|> skip (oneOf ".,!?:)|") <|> eof + endSpace = (spaceChar <|> newline) >> return B.space + +macro :: TWParser B.Inlines +macro = macroWithParameters <|> withoutParameters + where + withoutParameters = enclosed (char '%') (\_ -> macroName) >>= return . emptySpan + emptySpan name = buildSpan name [] mempty + +macroWithParameters :: TWParser B.Inlines +macroWithParameters = try $ do + char '%' + name <- macroName + (content, kvs) <- attributes + char '%' + return $ buildSpan name kvs $ B.str content + +buildSpan :: String -> [(String, String)] -> B.Inlines -> B.Inlines +buildSpan className kvs = B.spanWith attrs + where + attrs = ("", ["twiki-macro", className] ++ additionalClasses, kvsWithoutClasses) + additionalClasses = maybe [] words $ lookup "class" kvs + kvsWithoutClasses = [(k,v) | (k,v) <- kvs, k /= "class"] + +macroName :: TWParser String +macroName = do + first <- letter + rest <- many $ alphaNum <|> char '_' + return (first:rest) + +attributes :: TWParser (String, [(String, String)]) +attributes = char '{' *> spnl *> many (attribute <* spnl) <* char '}' >>= + return . foldr (either mkContent mkKvs) ([], []) + where + spnl = skipMany (spaceChar <|> newline) + mkContent c ([], kvs) = (c, kvs) + mkContent c (rest, kvs) = (c ++ " " ++ rest, kvs) + mkKvs kv (cont, rest) = (cont, (kv : rest)) + +attribute :: TWParser (Either String (String, String)) +attribute = withKey <|> withoutKey + where + withKey = try $ do + key <- macroName + char '=' + parseValue False >>= return . (curry Right key) + withoutKey = try $ parseValue True >>= return . Left + parseValue allowSpaces = (withQuotes <|> withoutQuotes allowSpaces) >>= return . fromEntities + withQuotes = between (char '"') (char '"') (\_ -> count 1 $ noneOf ['"']) + withoutQuotes allowSpaces + | allowSpaces == True = many1 $ noneOf "}" + | otherwise = many1 $ noneOf " }" + +nestedInlines :: Show a => TWParser a -> TWParser B.Inlines +nestedInlines end = innerSpace <|> nestedInline + where + innerSpace = try $ whitespace <* (notFollowedBy end) + nestedInline = notFollowedBy whitespace >> nested inline + +strong :: TWParser B.Inlines +strong = try $ enclosed (char '*') nestedInlines >>= return . B.strong + +strongHtml :: TWParser B.Inlines +strongHtml = (parseHtmlContent "strong" inline <|> parseHtmlContent "b" inline) + >>= return . B.strong . mconcat + +strongAndEmph :: TWParser B.Inlines +strongAndEmph = try $ enclosed (string "__") nestedInlines >>= return . B.emph . B.strong + +emph :: TWParser B.Inlines +emph = try $ enclosed (char '_') nestedInlines >>= return . B.emph + +emphHtml :: TWParser B.Inlines +emphHtml = (parseHtmlContent "em" inline <|> parseHtmlContent "i" inline) + >>= return . B.emph . mconcat + +nestedString :: Show a => TWParser a -> TWParser String +nestedString end = innerSpace <|> (count 1 nonspaceChar) + where + innerSpace = try $ many1 spaceChar <* notFollowedBy end + +boldCode :: TWParser B.Inlines +boldCode = try $ enclosed (string "==") nestedString >>= return . B.strong . B.code . fromEntities + +htmlComment :: TWParser B.Inlines +htmlComment = htmlTag isCommentTag >> return mempty + +code :: TWParser B.Inlines +code = try $ enclosed (char '=') nestedString >>= return . B.code . fromEntities + +codeHtml :: TWParser B.Inlines +codeHtml = do + (attrs, content) <- parseHtmlContentWithAttrs "code" anyChar + return $ B.codeWith attrs $ fromEntities content + +autoLink :: TWParser B.Inlines +autoLink = try $ do + state <- getState + guard $ stateAllowLinks state + (text, url) <- parseLink + guard $ checkLink (head $ reverse url) + return $ makeLink (text, url) + where + parseLink = notFollowedBy nop >> (uri <|> emailAddress) + makeLink (text, url) = B.link url "" $ B.str text + checkLink c + | c == '/' = True + | otherwise = isAlphaNum c + +str :: TWParser B.Inlines +str = (many1 alphaNum <|> count 1 characterReference) >>= return . B.str + +nop :: TWParser B.Inlines +nop = try $ (skip exclamation <|> skip nopTag) >> followContent + where + exclamation = char '!' + nopTag = stringAnyCase "" + followContent = many1 nonspaceChar >>= return . B.str . fromEntities + +symbol :: TWParser B.Inlines +symbol = count 1 nonspaceChar >>= return . B.str + +smart :: TWParser B.Inlines +smart = do + getOption readerSmart >>= guard + doubleQuoted <|> singleQuoted <|> + choice [ apostrophe + , dash + , ellipses + ] + +singleQuoted :: TWParser B.Inlines +singleQuoted = try $ do + singleQuoteStart + withQuoteContext InSingleQuote $ + many1Till inline singleQuoteEnd >>= + (return . B.singleQuoted . B.trimInlines . mconcat) + +doubleQuoted :: TWParser B.Inlines +doubleQuoted = try $ do + doubleQuoteStart + contents <- mconcat <$> many (try $ notFollowedBy doubleQuoteEnd >> inline) + (withQuoteContext InDoubleQuote $ doubleQuoteEnd >> + return (B.doubleQuoted $ B.trimInlines contents)) + <|> (return $ (B.str "\8220") B.<> contents) + +link :: TWParser B.Inlines +link = try $ do + st <- getState + guard $ stateAllowLinks st + setState $ st{ stateAllowLinks = False } + (url, title, content) <- linkText + setState $ st{ stateAllowLinks = True } + return $ B.link url title content + +linkText :: TWParser (String, String, B.Inlines) +linkText = do + string "[[" + url <- many1Till anyChar (char ']') + content <- option [B.str url] linkContent + char ']' + return (url, "", mconcat content) + where + linkContent = (char '[') >> many1Till anyChar (char ']') >>= parseLinkContent + parseLinkContent = parseFromString $ many1 inline -- cgit v1.2.3