{-# LANGUAGE OverloadedStrings #-} {- Copyright (C) 2006-2010 John MacFarlane 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.Writers.RST Copyright : Copyright (C) 2006-2010 John MacFarlane License : GNU GPL, version 2 or above Maintainer : John MacFarlane Stability : alpha Portability : portable Conversion of 'Pandoc' documents to reStructuredText. reStructuredText: -} module Text.Pandoc.Writers.RST ( writeRST) where import Text.Pandoc.Definition import Text.Pandoc.Shared import Text.Pandoc.Templates (renderTemplate) import Data.List ( isPrefixOf, intersperse, transpose ) import Text.Pandoc.Pretty import Control.Monad.State import Control.Applicative ( (<$>) ) type Refs = [([Inline], Target)] data WriterState = WriterState { stNotes :: [[Block]] , stLinks :: Refs , stImages :: Refs , stHasMath :: Bool , stOptions :: WriterOptions } -- | Convert Pandoc to RST. writeRST :: WriterOptions -> Pandoc -> String writeRST opts document = let st = WriterState { stNotes = [], stLinks = [], stImages = [], stHasMath = False, stOptions = opts } in evalState (pandocToRST document) st -- | Return RST representation of document. pandocToRST :: Pandoc -> State WriterState String pandocToRST (Pandoc (Meta tit auth dat) blocks) = do opts <- liftM stOptions get title <- titleToRST tit authors <- mapM inlineListToRST auth date <- inlineListToRST dat body <- blockListToRST blocks notes <- liftM (reverse . stNotes) get >>= notesToRST -- note that the notes may contain refs, so we do them first refs <- liftM (reverse . stLinks) get >>= refsToRST pics <- liftM (reverse . stImages) get >>= pictRefsToRST hasMath <- liftM stHasMath get let colwidth = if writerWrapText opts then Just $ writerColumns opts else Nothing let main = render colwidth $ foldl ($+$) empty $ [body, notes, refs, pics] let context = writerVariables opts ++ [ ("body", main) , ("title", render Nothing title) , ("date", render colwidth date) ] ++ [ ("math", "yes") | hasMath ] ++ [ ("author", render colwidth a) | a <- authors ] if writerStandalone opts then return $ renderTemplate context $ writerTemplate opts else return main -- | Return RST representation of reference key table. refsToRST :: Refs -> State WriterState Doc refsToRST refs = mapM keyToRST refs >>= return . vcat -- | Return RST representation of a reference key. keyToRST :: ([Inline], (String, String)) -> State WriterState Doc keyToRST (label, (src, _)) = do label' <- inlineListToRST label let label'' = if ':' `elem` (render Nothing label') then char '`' <> label' <> char '`' else label' return $ ".. _" <> label'' <> ": " <> text src -- | Return RST representation of notes. notesToRST :: [[Block]] -> State WriterState Doc notesToRST notes = mapM (\(num, note) -> noteToRST num note) (zip [1..] notes) >>= return . vsep -- | Return RST representation of a note. noteToRST :: Int -> [Block] -> State WriterState Doc noteToRST num note = do contents <- blockListToRST note let marker = ".. [" <> text (show num) <> "]" return $ marker $$ nest 3 contents -- | Return RST representation of picture reference table. pictRefsToRST :: Refs -> State WriterState Doc pictRefsToRST refs = mapM pictToRST refs >>= return . vcat -- | Return RST representation of a picture substitution reference. pictToRST :: ([Inline], (String, String)) -> State WriterState Doc pictToRST (label, (src, _)) = do label' <- inlineListToRST label return $ ".. |" <> label' <> "| image:: " <> text src -- | Escape special characters for RST. escapeString :: String -> String escapeString = escapeStringUsing (backslashEscapes "`\\|*_") titleToRST :: [Inline] -> State WriterState Doc titleToRST [] = return empty titleToRST lst = do contents <- inlineListToRST lst let titleLength = length $ (render Nothing contents :: String) let border = text (replicate titleLength '=') return $ border $$ contents $$ border -- | Convert Pandoc block element to RST. blockToRST :: Block -- ^ Block element -> State WriterState Doc blockToRST Null = return empty blockToRST (Plain inlines) = inlineListToRST inlines blockToRST (Para [Image txt (src,tit)]) = do capt <- inlineListToRST txt let fig = "figure:: " <> text src let align = ":align: center" let alt = ":alt: " <> if null tit then capt else text tit return $ hang 3 ".. " $ fig $$ align $$ alt $+$ capt $$ blankline blockToRST (Para inlines) = do contents <- inlineListToRST inlines return $ contents <> blankline blockToRST (RawBlock f str) = return $ blankline <> ".. raw:: " <> text f $+$ (nest 3 $ text str) $$ blankline blockToRST HorizontalRule = return $ blankline $$ "--------------" $$ blankline blockToRST (Header level inlines) = do contents <- inlineListToRST inlines let headerChar = if level > 5 then ' ' else "=-~^'" !! (level - 1) let border = text $ replicate (offset contents) headerChar return $ contents $$ border $$ blankline blockToRST (CodeBlock (_,classes,_) str) = do opts <- stOptions <$> get let tabstop = writerTabStop opts if "haskell" `elem` classes && "literate" `elem` classes && writerLiterateHaskell opts then return $ prefixed "> " (text str) $$ blankline else return $ "::" $+$ nest tabstop (text str) $$ blankline blockToRST (BlockQuote blocks) = do tabstop <- get >>= (return . writerTabStop . stOptions) contents <- blockListToRST blocks return $ (nest tabstop contents) <> blankline blockToRST (Table caption _ widths headers rows) = do caption' <- inlineListToRST caption let caption'' = if null caption then empty else blankline <> text "Table: " <> caption' headers' <- mapM blockListToRST headers rawRows <- mapM (mapM blockListToRST) rows let isSimple = all (==0) widths && all (all (\bs -> length bs == 1)) rows let numChars = maximum . map offset opts <- get >>= return . stOptions let widthsInChars = if isSimple then map ((+2) . numChars) $ transpose (headers' : rawRows) else map (floor . (fromIntegral (writerColumns opts) *)) widths let hpipeBlocks blocks = hcat [beg, middle, end] where h = maximum (map height blocks) sep' = lblock 3 $ vcat (map text $ replicate h " | ") beg = lblock 2 $ vcat (map text $ replicate h "| ") end = lblock 2 $ vcat (map text $ replicate h " |") middle = hcat $ intersperse sep' blocks let makeRow = hpipeBlocks . zipWith lblock widthsInChars let head' = makeRow headers' rows' <- mapM (\row -> do cols <- mapM blockListToRST row return $ makeRow cols) rows let border ch = char '+' <> char ch <> (hcat $ intersperse (char ch <> char '+' <> char ch) $ map (\l -> text $ replicate l ch) widthsInChars) <> char ch <> char '+' let body = vcat $ intersperse (border '-') rows' let head'' = if all null headers then empty else head' $$ border '=' return $ border '-' $$ head'' $$ body $$ border '-' $$ caption'' $$ blankline blockToRST (BulletList items) = do contents <- mapM bulletListItemToRST items -- ensure that sublists have preceding blank line return $ blankline $$ vcat contents $$ blankline blockToRST (OrderedList (start, style', delim) items) = do let markers = if start == 1 && style' == DefaultStyle && delim == DefaultDelim then take (length items) $ repeat "#." else take (length items) $ orderedListMarkers (start, style', delim) let maxMarkerLength = maximum $ map length markers let markers' = map (\m -> let s = maxMarkerLength - length m in m ++ replicate s ' ') markers contents <- mapM (\(item, num) -> orderedListItemToRST item num) $ zip markers' items -- ensure that sublists have preceding blank line return $ blankline $$ vcat contents $$ blankline blockToRST (DefinitionList items) = do contents <- mapM definitionListItemToRST items -- ensure that sublists have preceding blank line return $ blankline $$ vcat contents $$ blankline -- | Convert bullet list item (list of blocks) to RST. bulletListItemToRST :: [Block] -> State WriterState Doc bulletListItemToRST items = do contents <- blockListToRST items return $ hang 3 "- " $ contents <> cr -- | Convert ordered list item (a list of blocks) to RST. orderedListItemToRST :: String -- ^ marker for list item -> [Block] -- ^ list item (list of blocks) -> State WriterState Doc orderedListItemToRST marker items = do contents <- blockListToRST items let marker' = marker ++ " " return $ hang (length marker') (text marker') $ contents <> cr -- | Convert defintion list item (label, list of blocks) to RST. definitionListItemToRST :: ([Inline], [[Block]]) -> State WriterState Doc definitionListItemToRST (label, defs) = do label' <- inlineListToRST label contents <- liftM vcat $ mapM blockListToRST defs tabstop <- get >>= (return . writerTabStop . stOptions) return $ label' $$ nest tabstop (contents <> cr) -- | Convert list of Pandoc block elements to RST. blockListToRST :: [Block] -- ^ List of block elements -> State WriterState Doc blockListToRST blocks = mapM blockToRST blocks >>= return . vcat -- | Convert list of Pandoc inline elements to RST. inlineListToRST :: [Inline] -> State WriterState Doc inlineListToRST lst = mapM inlineToRST lst >>= return . hcat -- | Convert Pandoc inline element to RST. inlineToRST :: Inline -> State WriterState Doc inlineToRST (Emph lst) = do contents <- inlineListToRST lst return $ "*" <> contents <> "*" inlineToRST (Strong lst) = do contents <- inlineListToRST lst return $ "**" <> contents <> "**" inlineToRST (Strikeout lst) = do contents <- inlineListToRST lst return $ "[STRIKEOUT:" <> contents <> "]" inlineToRST (Superscript lst) = do contents <- inlineListToRST lst return $ "\\ :sup:`" <> contents <> "`\\ " inlineToRST (Subscript lst) = do contents <- inlineListToRST lst return $ "\\ :sub:`" <> contents <> "`\\ " inlineToRST (SmallCaps lst) = inlineListToRST lst inlineToRST (Quoted SingleQuote lst) = do contents <- inlineListToRST lst return $ "‘" <> contents <> "’" inlineToRST (Quoted DoubleQuote lst) = do contents <- inlineListToRST lst return $ "“" <> contents <> "”" inlineToRST (Cite _ lst) = inlineListToRST lst inlineToRST EmDash = return $ char '\8212' inlineToRST EnDash = return $ char '\8211' inlineToRST Apostrophe = return $ char '\8217' inlineToRST Ellipses = return $ char '\8230' inlineToRST (Code _ str) = return $ "``" <> text str <> "``" inlineToRST (Str str) = return $ text $ escapeString str inlineToRST (Math t str) = do modify $ \st -> st{ stHasMath = True } return $ if t == InlineMath then ":math:`$" <> text str <> "$`" else ":math:`$$" <> text str <> "$$`" inlineToRST (RawInline _ _) = return empty inlineToRST (LineBreak) = return cr -- there's no line break in RST inlineToRST Space = return space inlineToRST (Link [Code _ str] (src, _)) | src == str || src == "mailto:" ++ str = do let srcSuffix = if isPrefixOf "mailto:" src then drop 7 src else src return $ text $ unescapeURI srcSuffix inlineToRST (Link txt (src', tit)) = do let src = unescapeURI src' useReferenceLinks <- get >>= return . writerReferenceLinks . stOptions linktext <- inlineListToRST $ normalizeSpaces txt if useReferenceLinks then do refs <- get >>= return . stLinks let refs' = if (txt, (src, tit)) `elem` refs then refs else (txt, (src, tit)):refs modify $ \st -> st { stLinks = refs' } return $ "`" <> linktext <> "`_" else return $ "`" <> linktext <> " <" <> text src <> ">`_" inlineToRST (Image alternate (source', tit)) = do let source = unescapeURI source' pics <- get >>= return . stImages let labelsUsed = map fst pics let txt = if null alternate || alternate == [Str ""] || alternate `elem` labelsUsed then [Str $ "image" ++ show (length pics)] else alternate let pics' = if (txt, (source, tit)) `elem` pics then pics else (txt, (source, tit)):pics modify $ \st -> st { stImages = pics' } label <- inlineListToRST txt return $ "|" <> label <> "|" inlineToRST (Note contents) = do -- add to notes in state notes <- get >>= return . stNotes modify $ \st -> st { stNotes = contents:notes } let ref = show $ (length notes) + 1 return $ " [" <> text ref <> "]_"