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{-# LANGUAGE NoImplicitPrelude #-}
{-
Copyright (C) 2007-2018 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.Writers.Ms
Copyright : Copyright (C) 2007-2018 John MacFarlane
License : GNU GPL, version 2 or above
Maintainer : John MacFarlane <jgm@berkeley.edu>
Stability : alpha
Portability : portable
Conversion of 'Pandoc' documents to roff ms format.
TODO:
[ ] use base URL to construct absolute URLs from relative ones for external
links
[ ] is there a better way to do strikeout?
[ ] tight/loose list distinction
-}
module Text.Pandoc.Writers.Ms ( writeMs ) where
import Prelude
import Control.Monad.State.Strict
import Data.Char (isLower, isUpper, toUpper, ord)
import Data.List (intercalate, intersperse)
import qualified Data.Map as Map
import Data.Maybe (catMaybes, fromMaybe)
import Data.Text (Text)
import qualified Data.Text as T
import Network.URI (escapeURIString, isAllowedInURI)
import Skylighting
import System.FilePath (takeExtension)
import Text.Pandoc.Asciify (toAsciiChar)
import Text.Pandoc.Class (PandocMonad, report)
import Text.Pandoc.Definition
import Text.Pandoc.Highlighting
import Text.Pandoc.ImageSize
import Text.Pandoc.Logging
import Text.Pandoc.Options
import Text.Pandoc.Pretty
import Text.Pandoc.Shared
import Text.Pandoc.Templates
import Text.Pandoc.Writers.Math
import Text.Pandoc.Writers.Shared
import Text.Pandoc.Writers.Roff
import Text.Printf (printf)
import Text.TeXMath (writeEqn)
-- | Convert Pandoc to Ms.
writeMs :: PandocMonad m => WriterOptions -> Pandoc -> m Text
writeMs opts document =
evalStateT (pandocToMs opts document) defaultWriterState
-- | Return roff ms representation of document.
pandocToMs :: PandocMonad m => WriterOptions -> Pandoc -> MS m Text
pandocToMs opts (Pandoc meta blocks) = do
let colwidth = if writerWrapText opts == WrapAuto
then Just $ writerColumns opts
else Nothing
let render' :: Doc -> Text
render' = render colwidth
metadata <- metaToJSON opts
(fmap render' . blockListToMs opts)
(fmap render' . inlineListToMs' opts)
meta
body <- blockListToMs opts blocks
let main = render' body
hasInlineMath <- gets stHasInlineMath
let titleMeta = (escapeStr opts . stringify) $ docTitle meta
let authorsMeta = map (escapeStr opts . stringify) $ docAuthors meta
hasHighlighting <- gets stHighlighting
let highlightingMacros = if hasHighlighting
then case writerHighlightStyle opts of
Nothing -> mempty
Just sty -> render' $ styleToMs sty
else mempty
let context = defField "body" main
$ defField "has-inline-math" hasInlineMath
$ defField "hyphenate" True
$ defField "pandoc-version" pandocVersion
$ defField "toc" (writerTableOfContents opts)
$ defField "title-meta" titleMeta
$ defField "author-meta" (intercalate "; " authorsMeta)
$ defField "highlighting-macros" highlightingMacros metadata
case writerTemplate opts of
Nothing -> return main
Just tpl -> renderTemplate' tpl context
escapeStr :: WriterOptions -> String -> String
escapeStr opts =
escapeString (if writerPreferAscii opts then AsciiOnly else AllowUTF8)
escapeUri :: String -> String
escapeUri = escapeURIString (\c -> c /= '@' && isAllowedInURI c)
toSmallCaps :: WriterOptions -> String -> String
toSmallCaps _ [] = []
toSmallCaps opts (c:cs)
| isLower c = let (lowers,rest) = span isLower (c:cs)
in "\\s-2" ++ escapeStr opts (map toUpper lowers) ++
"\\s0" ++ toSmallCaps opts rest
| isUpper c = let (uppers,rest) = span isUpper (c:cs)
in escapeStr opts uppers ++ toSmallCaps opts rest
| otherwise = escapeStr opts [c] ++ toSmallCaps opts cs
-- We split inline lists into sentences, and print one sentence per
-- line. roff treats the line-ending period differently.
-- See http://code.google.com/p/pandoc/issues/detail?id=148.
blockToMs :: PandocMonad m
=> WriterOptions -- ^ Options
-> Block -- ^ Block element
-> MS m Doc
blockToMs _ Null = return empty
blockToMs opts (Div (ident,_,_) bs) = do
let anchor = if null ident
then empty
else nowrap $
text ".pdfhref M "
<> doubleQuotes (text (toAscii ident))
setFirstPara
res <- blockListToMs opts bs
setFirstPara
return $ anchor $$ res
blockToMs opts (Plain inlines) =
liftM vcat $ mapM (inlineListToMs' opts) $ splitSentences inlines
blockToMs opts (Para [Image attr alt (src,_tit)])
| let ext = takeExtension src in (ext == ".ps" || ext == ".eps") = do
let (mbW,mbH) = (inPoints opts <$> dimension Width attr,
inPoints opts <$> dimension Height attr)
let sizeAttrs = case (mbW, mbH) of
(Just wp, Nothing) -> space <> doubleQuotes
(text (show (floor wp :: Int) ++ "p"))
(Just wp, Just hp) -> space <> doubleQuotes
(text (show (floor wp :: Int) ++ "p")) <>
space <>
doubleQuotes (text (show (floor hp :: Int)))
_ -> empty
capt <- inlineListToMs' opts alt
return $ nowrap (text ".PSPIC -C " <>
doubleQuotes (text (escapeStr opts src)) <>
sizeAttrs) $$
text ".ce 1000" $$
capt $$
text ".ce 0"
blockToMs opts (Para inlines) = do
firstPara <- gets stFirstPara
resetFirstPara
contents <- liftM vcat $ mapM (inlineListToMs' opts) $
splitSentences inlines
return $ text (if firstPara then ".LP" else ".PP") $$ contents
blockToMs _ b@(RawBlock f str)
| f == Format "ms" = return $ text str
| otherwise = do
report $ BlockNotRendered b
return empty
blockToMs _ HorizontalRule = do
resetFirstPara
return $ text ".HLINE"
blockToMs opts (Header level (ident,classes,_) inlines) = do
setFirstPara
modify $ \st -> st{ stInHeader = True }
contents <- inlineListToMs' opts $ map breakToSpace inlines
modify $ \st -> st{ stInHeader = False }
let (heading, secnum) = if writerNumberSections opts &&
"unnumbered" `notElem` classes
then (".NH", "\\*[SN]")
else (".SH", "")
let anchor = if null ident
then empty
else nowrap $
text ".pdfhref M "
<> doubleQuotes (text (toAscii ident))
let bookmark = text ".pdfhref O " <> text (show level ++ " ") <>
doubleQuotes (text $ secnum ++
(if null secnum
then ""
else " ") ++
escapeStr opts (stringify inlines))
let backlink = nowrap (text ".pdfhref L -D " <>
doubleQuotes (text (toAscii ident)) <> space <> text "\\") <> cr <>
text " -- "
let tocEntry = if writerTableOfContents opts &&
level <= writerTOCDepth opts
then text ".XS"
$$ backlink <> doubleQuotes (
nowrap (text (replicate level '\t') <>
(if null secnum
then empty
else text secnum <> text "\\~\\~")
<> contents))
$$ text ".XE"
else empty
modify $ \st -> st{ stFirstPara = True }
return $ (text heading <> space <> text (show level)) $$
contents $$
bookmark $$
anchor $$
tocEntry
blockToMs opts (CodeBlock attr str) = do
hlCode <- highlightCode opts attr str
setFirstPara
return $
text ".IP" $$
text ".nf" $$
text "\\f[C]" $$
hlCode $$
text "\\f[]" $$
text ".fi"
blockToMs opts (LineBlock ls) = do
resetFirstPara
blockToMs opts $ Para $ intercalate [LineBreak] ls
blockToMs opts (BlockQuote blocks) = do
setFirstPara
contents <- blockListToMs opts blocks
setFirstPara
return $ text ".RS" $$ contents $$ text ".RE"
blockToMs opts (Table caption alignments widths headers rows) =
let aligncode AlignLeft = "l"
aligncode AlignRight = "r"
aligncode AlignCenter = "c"
aligncode AlignDefault = "l"
in do
caption' <- inlineListToMs' opts caption
let iwidths = if all (== 0) widths
then repeat ""
else map (printf "w(%0.1fn)" . (70 *)) widths
-- 78n default width - 8n indent = 70n
let coldescriptions = text $ unwords
(zipWith (\align width -> aligncode align ++ width)
alignments iwidths) ++ "."
colheadings <- mapM (blockListToMs opts) headers
let makeRow cols = text "T{" $$
vcat (intersperse (text "T}\tT{") cols) $$
text "T}"
let colheadings' = if all null headers
then empty
else makeRow colheadings $$ char '_'
body <- mapM (\row -> do
cols <- mapM (blockListToMs opts) row
return $ makeRow cols) rows
setFirstPara
return $ text ".PP" $$ caption' $$
text ".TS" $$ text "delim(@@) tab(\t);" $$ coldescriptions $$
colheadings' $$ vcat body $$ text ".TE"
blockToMs opts (BulletList items) = do
contents <- mapM (bulletListItemToMs opts) items
setFirstPara
return (vcat contents)
blockToMs opts (OrderedList attribs items) = do
let markers = take (length items) $ orderedListMarkers attribs
let indent = 2 +
maximum (map length markers)
contents <- mapM (\(num, item) -> orderedListItemToMs opts num indent item) $
zip markers items
setFirstPara
return (vcat contents)
blockToMs opts (DefinitionList items) = do
contents <- mapM (definitionListItemToMs opts) items
setFirstPara
return (vcat contents)
-- | Convert bullet list item (list of blocks) to ms.
bulletListItemToMs :: PandocMonad m => WriterOptions -> [Block] -> MS m Doc
bulletListItemToMs _ [] = return empty
bulletListItemToMs opts (Para first:rest) =
bulletListItemToMs opts (Plain first:rest)
bulletListItemToMs opts (Plain first:rest) = do
first' <- blockToMs opts (Plain first)
rest' <- blockListToMs opts rest
let first'' = text ".IP \\[bu] 3" $$ first'
let rest'' = if null rest
then empty
else text ".RS 3" $$ rest' $$ text ".RE"
return (first'' $$ rest'')
bulletListItemToMs opts (first:rest) = do
first' <- blockToMs opts first
rest' <- blockListToMs opts rest
return $ text "\\[bu] .RS 3" $$ first' $$ rest' $$ text ".RE"
-- | Convert ordered list item (a list of blocks) to ms.
orderedListItemToMs :: PandocMonad m
=> WriterOptions -- ^ options
-> String -- ^ order marker for list item
-> Int -- ^ number of spaces to indent
-> [Block] -- ^ list item (list of blocks)
-> MS m Doc
orderedListItemToMs _ _ _ [] = return empty
orderedListItemToMs opts num indent (Para first:rest) =
orderedListItemToMs opts num indent (Plain first:rest)
orderedListItemToMs opts num indent (first:rest) = do
first' <- blockToMs opts first
rest' <- blockListToMs opts rest
let num' = printf ("%" ++ show (indent - 1) ++ "s") num
let first'' = text (".IP \"" ++ num' ++ "\" " ++ show indent) $$ first'
let rest'' = if null rest
then empty
else text ".RS " <> text (show indent) $$
rest' $$ text ".RE"
return $ first'' $$ rest''
-- | Convert definition list item (label, list of blocks) to ms.
definitionListItemToMs :: PandocMonad m
=> WriterOptions
-> ([Inline],[[Block]])
-> MS m Doc
definitionListItemToMs opts (label, defs) = do
labelText <- inlineListToMs' opts $ map breakToSpace label
contents <- if null defs
then return empty
else liftM vcat $ forM defs $ \blocks -> do
let (first, rest) = case blocks of
(Para x:y) -> (Plain x,y)
(x:y) -> (x,y)
[] -> (Plain [], [])
-- should not happen
rest' <- liftM vcat $
mapM (\item -> blockToMs opts item) rest
first' <- blockToMs opts first
return $ first' $$ text ".RS" $$ rest' $$ text ".RE"
return $ nowrap (text ".IP " <> doubleQuotes labelText) $$ contents
-- | Convert list of Pandoc block elements to ms.
blockListToMs :: PandocMonad m
=> WriterOptions -- ^ Options
-> [Block] -- ^ List of block elements
-> MS m Doc
blockListToMs opts blocks =
vcat <$> mapM (blockToMs opts) blocks
-- | Convert list of Pandoc inline elements to ms.
inlineListToMs :: PandocMonad m => WriterOptions -> [Inline] -> MS m Doc
-- if list starts with ., insert a zero-width character \& so it
-- won't be interpreted as markup if it falls at the beginning of a line.
inlineListToMs opts lst = hcat <$> mapM (inlineToMs opts) lst
-- This version to be used when there is no further inline content;
-- forces a note at the end.
inlineListToMs' :: PandocMonad m => WriterOptions -> [Inline] -> MS m Doc
inlineListToMs' opts lst = do
x <- hcat <$> mapM (inlineToMs opts) lst
y <- handleNotes opts empty
return $ x <> y
-- | Convert Pandoc inline element to ms.
inlineToMs :: PandocMonad m => WriterOptions -> Inline -> MS m Doc
inlineToMs opts (Span _ ils) = inlineListToMs opts ils
inlineToMs opts (Emph lst) =
withFontFeature 'I' (inlineListToMs opts lst)
inlineToMs opts (Strong lst) =
withFontFeature 'B' (inlineListToMs opts lst)
inlineToMs opts (Strikeout lst) = do
contents <- inlineListToMs opts lst
-- we use grey color instead of strikeout, which seems quite
-- hard to do in roff for arbitrary bits of text
return $ text "\\m[strikecolor]" <> contents <> text "\\m[]"
inlineToMs opts (Superscript lst) = do
contents <- inlineListToMs opts lst
return $ text "\\*{" <> contents <> text "\\*}"
inlineToMs opts (Subscript lst) = do
contents <- inlineListToMs opts lst
return $ text "\\*<" <> contents <> text "\\*>"
inlineToMs opts (SmallCaps lst) = do
-- see https://lists.gnu.org/archive/html/groff/2015-01/msg00016.html
modify $ \st -> st{ stSmallCaps = not (stSmallCaps st) }
res <- inlineListToMs opts lst
modify $ \st -> st{ stSmallCaps = not (stSmallCaps st) }
return res
inlineToMs opts (Quoted SingleQuote lst) = do
contents <- inlineListToMs opts lst
return $ char '`' <> contents <> char '\''
inlineToMs opts (Quoted DoubleQuote lst) = do
contents <- inlineListToMs opts lst
return $ text "\\[lq]" <> contents <> text "\\[rq]"
inlineToMs opts (Cite _ lst) =
inlineListToMs opts lst
inlineToMs opts (Code attr str) = do
hlCode <- highlightCode opts attr str
withFontFeature 'C' (return hlCode)
inlineToMs opts (Str str) = do
let shim = case str of
'.':_ -> afterBreak "\\&"
_ -> empty
smallcaps <- gets stSmallCaps
if smallcaps
then return $ shim <> text (toSmallCaps opts str)
else return $ shim <> text (escapeStr opts str)
inlineToMs opts (Math InlineMath str) = do
modify $ \st -> st{ stHasInlineMath = True }
res <- convertMath writeEqn InlineMath str
case res of
Left il -> inlineToMs opts il
Right r -> return $ text "@" <> text r <> text "@"
inlineToMs opts (Math DisplayMath str) = do
res <- convertMath writeEqn InlineMath str
case res of
Left il -> do
contents <- inlineToMs opts il
return $ cr <> text ".RS" $$ contents $$ text ".RE"
Right r -> return $
cr <> text ".EQ" $$ text r $$ text ".EN"
inlineToMs _ il@(RawInline f str)
| f == Format "ms" = return $ text str
| otherwise = do
report $ InlineNotRendered il
return empty
inlineToMs _ LineBreak = return $ cr <> text ".br" <> cr
inlineToMs opts SoftBreak =
handleNotes opts $
case writerWrapText opts of
WrapAuto -> space
WrapNone -> space
WrapPreserve -> cr
inlineToMs opts Space = handleNotes opts space
inlineToMs opts (Link _ txt ('#':ident, _)) = do
-- internal link
contents <- inlineListToMs' opts $ map breakToSpace txt
return $ text "\\c" <> cr <> nowrap (text ".pdfhref L -D " <>
doubleQuotes (text (toAscii ident)) <> text " -A " <>
doubleQuotes (text "\\c") <> space <> text "\\") <> cr <>
text " -- " <> doubleQuotes (nowrap contents) <> cr <> text "\\&"
inlineToMs opts (Link _ txt (src, _)) = do
-- external link
contents <- inlineListToMs' opts $ map breakToSpace txt
return $ text "\\c" <> cr <> nowrap (text ".pdfhref W -D " <>
doubleQuotes (text (escapeUri src)) <> text " -A " <>
doubleQuotes (text "\\c") <> space <> text "\\") <> cr <>
text " -- " <> doubleQuotes (nowrap contents) <> cr <> text "\\&"
inlineToMs opts (Image _ alternate (_, _)) =
return $ char '[' <> text "IMAGE: " <>
text (escapeStr opts (stringify alternate))
<> char ']'
inlineToMs _ (Note contents) = do
modify $ \st -> st{ stNotes = contents : stNotes st }
return $ text "\\**"
handleNotes :: PandocMonad m => WriterOptions -> Doc -> MS m Doc
handleNotes opts fallback = do
notes <- gets stNotes
if null notes
then return fallback
else do
modify $ \st -> st{ stNotes = [] }
vcat <$> mapM (handleNote opts) notes
handleNote :: PandocMonad m => WriterOptions -> Note -> MS m Doc
handleNote opts bs = do
-- don't start with Paragraph or we'll get a spurious blank
-- line after the note ref:
let bs' = case bs of
(Para ils : rest) -> Plain ils : rest
_ -> bs
contents <- blockListToMs opts bs'
return $ cr <> text ".FS" $$ contents $$ text ".FE" <> cr
setFirstPara :: PandocMonad m => MS m ()
setFirstPara = modify $ \st -> st{ stFirstPara = True }
resetFirstPara :: PandocMonad m => MS m ()
resetFirstPara = modify $ \st -> st{ stFirstPara = False }
breakToSpace :: Inline -> Inline
breakToSpace SoftBreak = Space
breakToSpace LineBreak = Space
breakToSpace x = x
-- Highlighting
styleToMs :: Style -> Doc
styleToMs sty = vcat $ colordefs ++ map (toMacro sty) alltoktypes
where alltoktypes = enumFromTo KeywordTok NormalTok
colordefs = map toColorDef allcolors
toColorDef c = text (".defcolor " ++
hexColor c ++ " rgb #" ++ hexColor c)
allcolors = catMaybes $ ordNub $
[defaultColor sty, backgroundColor sty,
lineNumberColor sty, lineNumberBackgroundColor sty] ++
concatMap (colorsForToken. snd) (Map.toList (tokenStyles sty))
colorsForToken ts = [tokenColor ts, tokenBackground ts]
hexColor :: Color -> String
hexColor (RGB r g b) = printf "%02x%02x%02x" r g b
toMacro :: Style -> TokenType -> Doc
toMacro sty toktype =
nowrap (text ".ds " <> text (show toktype) <> text " " <>
setbg <> setcolor <> setfont <>
text "\\\\$1" <>
resetfont <> resetcolor <> resetbg)
where setcolor = maybe empty fgcol tokCol
resetcolor = maybe empty (const $ text "\\\\m[]") tokCol
setbg = empty -- maybe empty bgcol tokBg
resetbg = empty -- maybe empty (const $ text "\\\\M[]") tokBg
fgcol c = text $ "\\\\m[" ++ hexColor c ++ "]"
-- bgcol c = text $ "\\\\M[" ++ hexColor c ++ "]"
setfont = if tokBold || tokItalic
then text $ "\\\\f[C" ++ ['B' | tokBold] ++
['I' | tokItalic] ++ "]"
else empty
resetfont = if tokBold || tokItalic
then text "\\\\f[C]"
else empty
tokSty = Map.lookup toktype (tokenStyles sty)
tokCol = (tokSty >>= tokenColor) `mplus` defaultColor sty
-- tokBg = (tokSty >>= tokenBackground) `mplus` backgroundColor sty
tokBold = fromMaybe False (tokenBold <$> tokSty)
tokItalic = fromMaybe False (tokenItalic <$> tokSty)
-- tokUnderline = fromMaybe False (tokSty >>= tokUnderline)
-- lnColor = lineNumberColor sty
-- lnBkgColor = lineNumberBackgroundColor sty
msFormatter :: WriterOptions -> FormatOptions -> [SourceLine] -> Doc
msFormatter opts _fmtopts =
vcat . map fmtLine
where fmtLine = hcat . map fmtToken
fmtToken (toktype, tok) = text "\\*" <>
brackets (text (show toktype) <> text " \""
<> text (escapeStr opts (T.unpack tok)) <> text "\"")
highlightCode :: PandocMonad m => WriterOptions -> Attr -> String -> MS m Doc
highlightCode opts attr str =
case highlight (writerSyntaxMap opts) (msFormatter opts) attr str of
Left msg -> do
unless (null msg) $ report $ CouldNotHighlight msg
return $ text (escapeStr opts str)
Right h -> do
modify (\st -> st{ stHighlighting = True })
return h
-- This is used for PDF anchors.
toAscii :: String -> String
toAscii = concatMap
(\c -> case toAsciiChar c of
Nothing -> '_':'u':show (ord c) ++ "_"
Just '/' -> '_':'u':show (ord c) ++ "_" -- see #4515
Just c' -> [c'])
|