{-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE OverloadedStrings #-} {- | Module : Text.Pandoc.Writers.Shared Copyright : Copyright (C) 2013-2019 John MacFarlane License : GNU GPL, version 2 or above Maintainer : John MacFarlane Stability : alpha Portability : portable Shared utility functions for pandoc writers. -} module Text.Pandoc.Writers.Shared ( metaToJSON , metaToJSON' , addVariablesToJSON , getField , setField , resetField , defField , tagWithAttrs , isDisplayMath , fixDisplayMath , unsmartify , gridTable , lookupMetaBool , lookupMetaBlocks , lookupMetaInlines , lookupMetaString , stripLeadingTrailingSpace , toSubscript , toSuperscript , toTableOfContents ) where import Prelude import Control.Monad (zipWithM) import qualified Data.Aeson as Aeson import Data.Aeson (FromJSON (..), Result (..), ToJSON (..), Value (Object), encode, fromJSON) import Data.Char (chr, ord, isSpace, isDigit) import qualified Data.HashMap.Strict as H import Data.List (groupBy, intersperse, transpose) import qualified Data.Map as M import Data.Maybe (isJust) import qualified Data.Text as T import qualified Data.Traversable as Traversable import qualified Text.Pandoc.Builder as Builder import Text.Pandoc.Definition import Text.Pandoc.Options import Text.Pandoc.Pretty import Text.Pandoc.Shared (stringify, hierarchicalize, Element(..), deNote, safeRead) import Text.Pandoc.Walk (walk) import Text.Pandoc.UTF8 (toStringLazy) import Text.Pandoc.XML (escapeStringForXML) -- | Create JSON value for template from a 'Meta' and an association list -- of variables, specified at the command line or in the writer. -- Variables overwrite metadata fields with the same names. -- If multiple variables are set with the same name, a list is -- assigned. Does nothing if 'writerTemplate' is Nothing. metaToJSON :: (Functor m, Monad m, ToJSON a) => WriterOptions -> ([Block] -> m a) -> ([Inline] -> m a) -> Meta -> m Value metaToJSON opts blockWriter inlineWriter meta | isJust (writerTemplate opts) = addVariablesToJSON opts <$> metaToJSON' blockWriter inlineWriter meta | otherwise = return (Object H.empty) -- | Like 'metaToJSON', but does not include variables and is -- not sensitive to 'writerTemplate'. metaToJSON' :: (Functor m, Monad m, ToJSON a) => ([Block] -> m a) -> ([Inline] -> m a) -> Meta -> m Value metaToJSON' blockWriter inlineWriter (Meta metamap) = do renderedMap <- Traversable.mapM (metaValueToJSON blockWriter inlineWriter) metamap return $ M.foldrWithKey defField (Object H.empty) renderedMap -- | Add variables to JSON object, replacing any existing values. -- Also include @meta-json@, a field containing a string representation -- of the original JSON object itself, prior to addition of variables. addVariablesToJSON :: WriterOptions -> Value -> Value addVariablesToJSON opts metadata = foldl (\acc (x,y) -> setField x y acc) (defField "meta-json" (toStringLazy $ encode metadata) (Object mempty)) (writerVariables opts) `combineMetadata` metadata where combineMetadata (Object o1) (Object o2) = Object $ H.union o1 o2 combineMetadata x _ = x metaValueToJSON :: (Functor m, Monad m, ToJSON a) => ([Block] -> m a) -> ([Inline] -> m a) -> MetaValue -> m Value metaValueToJSON blockWriter inlineWriter (MetaMap metamap) = toJSON <$> Traversable.mapM (metaValueToJSON blockWriter inlineWriter) metamap metaValueToJSON blockWriter inlineWriter (MetaList xs) = toJSON <$> Traversable.mapM (metaValueToJSON blockWriter inlineWriter) xs metaValueToJSON _ _ (MetaBool b) = return $ toJSON b metaValueToJSON _ inlineWriter (MetaString s) = if all isDigit s then return $ maybe (Aeson.String . T.pack $ s) Aeson.Number $ safeRead s else toJSON <$> inlineWriter (Builder.toList (Builder.text s)) metaValueToJSON blockWriter _ (MetaBlocks bs) = toJSON <$> blockWriter bs metaValueToJSON _ inlineWriter (MetaInlines is) = toJSON <$> inlineWriter is -- | Retrieve a field value from a JSON object. getField :: FromJSON a => String -> Value -> Maybe a getField field (Object hashmap) = do result <- H.lookup (T.pack field) hashmap case fromJSON result of Success x -> return x _ -> fail "Could not convert from JSON" getField _ _ = fail "Not a JSON object" setField :: ToJSON a => String -> a -> Value -> Value -- | Set a field of a JSON object. If the field already has a value, -- convert it into a list with the new value appended to the old value(s). -- This is a utility function to be used in preparing template contexts. setField field val (Object hashmap) = Object $ H.insertWith combine (T.pack field) (toJSON val) hashmap where combine newval oldval = case fromJSON oldval of Success xs -> toJSON $ xs ++ [newval] _ -> toJSON [oldval, newval] setField _ _ x = x resetField :: ToJSON a => String -> a -> Value -> Value -- | Reset a field of a JSON object. If the field already has a value, -- the new value replaces it. -- This is a utility function to be used in preparing template contexts. resetField field val (Object hashmap) = Object $ H.insert (T.pack field) (toJSON val) hashmap resetField _ _ x = x defField :: ToJSON a => String -> a -> Value -> Value -- | Set a field of a JSON object if it currently has no value. -- If it has a value, do nothing. -- This is a utility function to be used in preparing template contexts. defField field val (Object hashmap) = Object $ H.insertWith f (T.pack field) (toJSON val) hashmap where f _newval oldval = oldval defField _ _ x = x -- Produce an HTML tag with the given pandoc attributes. tagWithAttrs :: String -> Attr -> Doc tagWithAttrs tag (ident,classes,kvs) = hsep ["<" <> text tag ,if null ident then empty else "id=" <> doubleQuotes (text ident) ,if null classes then empty else "class=" <> doubleQuotes (text (unwords classes)) ,hsep (map (\(k,v) -> text k <> "=" <> doubleQuotes (text (escapeStringForXML v))) kvs) ] <> ">" isDisplayMath :: Inline -> Bool isDisplayMath (Math DisplayMath _) = True isDisplayMath (Span _ [Math DisplayMath _]) = True isDisplayMath _ = False stripLeadingTrailingSpace :: [Inline] -> [Inline] stripLeadingTrailingSpace = go . reverse . go . reverse where go (Space:xs) = xs go (SoftBreak:xs) = xs go xs = xs -- Put display math in its own block (for ODT/DOCX). fixDisplayMath :: Block -> Block fixDisplayMath (Plain lst) | any isDisplayMath lst && not (all isDisplayMath lst) = -- chop into several paragraphs so each displaymath is its own Div ("",["math"],[]) $ map Plain $ filter (not . null) $ map stripLeadingTrailingSpace $ groupBy (\x y -> (isDisplayMath x && isDisplayMath y) || not (isDisplayMath x || isDisplayMath y)) lst fixDisplayMath (Para lst) | any isDisplayMath lst && not (all isDisplayMath lst) = -- chop into several paragraphs so each displaymath is its own Div ("",["math"],[]) $ map Para $ filter (not . null) $ map stripLeadingTrailingSpace $ groupBy (\x y -> (isDisplayMath x && isDisplayMath y) || not (isDisplayMath x || isDisplayMath y)) lst fixDisplayMath x = x unsmartify :: WriterOptions -> String -> String unsmartify opts ('\8217':xs) = '\'' : unsmartify opts xs unsmartify opts ('\8230':xs) = "..." ++ unsmartify opts xs unsmartify opts ('\8211':xs) | isEnabled Ext_old_dashes opts = '-' : unsmartify opts xs | otherwise = "--" ++ unsmartify opts xs unsmartify opts ('\8212':xs) | isEnabled Ext_old_dashes opts = "--" ++ unsmartify opts xs | otherwise = "---" ++ unsmartify opts xs unsmartify opts ('\8220':xs) = '"' : unsmartify opts xs unsmartify opts ('\8221':xs) = '"' : unsmartify opts xs unsmartify opts ('\8216':xs) = '\'' : unsmartify opts xs unsmartify opts (x:xs) = x : unsmartify opts xs unsmartify _ [] = [] gridTable :: Monad m => WriterOptions -> (WriterOptions -> [Block] -> m Doc) -> Bool -- ^ headless -> [Alignment] -> [Double] -> [[Block]] -> [[[Block]]] -> m Doc gridTable opts blocksToDoc headless aligns widths headers rows = do -- the number of columns will be used in case of even widths let numcols = maximum (length aligns : length widths : map length (headers:rows)) -- handleGivenWidths wraps the given blocks in order for them to fit -- in cells with given widths. the returned content can be -- concatenated with borders and frames let handleGivenWidths widths' = do let widthsInChars' = map ( (\x -> if x < 1 then 1 else x) . (\x -> x - 3) . floor . (fromIntegral (writerColumns opts) *) ) widths' -- replace page width (in columns) in the options with a -- given width if smaller (adjusting by two) useWidth w = opts{writerColumns = min (w - 2) (writerColumns opts)} -- prepare options to use with header and row cells columnOptions = map useWidth widthsInChars' rawHeaders' <- zipWithM blocksToDoc columnOptions headers rawRows' <- mapM (\cs -> zipWithM blocksToDoc columnOptions cs) rows return (widthsInChars', rawHeaders', rawRows') -- handleFullWidths tries to wrap cells to the page width or even -- more in cases where `--wrap=none`. thus the content here is left -- as wide as possible let handleFullWidths = do rawHeaders' <- mapM (blocksToDoc opts) headers rawRows' <- mapM (mapM (blocksToDoc opts)) rows let numChars [] = 0 numChars xs = maximum . map offset $ xs let widthsInChars' = map numChars $ transpose (rawHeaders' : rawRows') return (widthsInChars', rawHeaders', rawRows') -- handleZeroWidths calls handleFullWidths to check whether a wide -- table would fit in the page. if the produced table is too wide, -- it calculates even widths and passes the content to -- handleGivenWidths let handleZeroWidths = do (widthsInChars', rawHeaders', rawRows') <- handleFullWidths if sum widthsInChars' > writerColumns opts then -- use even widths handleGivenWidths (replicate numcols (1.0 / fromIntegral numcols) :: [Double]) else return (widthsInChars', rawHeaders', rawRows') -- render the contents of header and row cells differently depending -- on command line options, widths given in this specific table, and -- cells' contents let handleWidths | writerWrapText opts == WrapNone = handleFullWidths | all (== 0) widths = handleZeroWidths | otherwise = handleGivenWidths widths (widthsInChars, rawHeaders, rawRows) <- handleWidths let hpipeBlocks blocks = hcat [beg, middle, end] where h = maximum (1 : map height blocks) sep' = lblock 3 $ vcat (replicate h (text " | ")) beg = lblock 2 $ vcat (replicate h (text "| ")) end = lblock 2 $ vcat (replicate h (text " |")) middle = chomp $ hcat $ intersperse sep' blocks let makeRow = hpipeBlocks . zipWith lblock widthsInChars let head' = makeRow rawHeaders let rows' = map (makeRow . map chomp) rawRows let borderpart ch align widthInChars = (if align == AlignLeft || align == AlignCenter then char ':' else char ch) <> text (replicate widthInChars ch) <> (if align == AlignRight || align == AlignCenter then char ':' else char ch) let border ch aligns' widthsInChars' = char '+' <> hcat (intersperse (char '+') (zipWith (borderpart ch) aligns' widthsInChars')) <> char '+' let body = vcat $ intersperse (border '-' (repeat AlignDefault) widthsInChars) rows' let head'' = if headless then empty else head' $$ border '=' aligns widthsInChars if headless then return $ border '-' aligns widthsInChars $$ body $$ border '-' (repeat AlignDefault) widthsInChars else return $ border '-' (repeat AlignDefault) widthsInChars $$ head'' $$ body $$ border '-' (repeat AlignDefault) widthsInChars -- | Retrieve the metadata value for a given @key@ -- and convert to Bool. lookupMetaBool :: String -> Meta -> Bool lookupMetaBool key meta = case lookupMeta key meta of Just (MetaBlocks _) -> True Just (MetaInlines _) -> True Just (MetaString (_:_)) -> True Just (MetaBool True) -> True _ -> False -- | Retrieve the metadata value for a given @key@ -- and extract blocks. lookupMetaBlocks :: String -> Meta -> [Block] lookupMetaBlocks key meta = case lookupMeta key meta of Just (MetaBlocks bs) -> bs Just (MetaInlines ils) -> [Plain ils] Just (MetaString s) -> [Plain [Str s]] _ -> [] -- | Retrieve the metadata value for a given @key@ -- and extract inlines. lookupMetaInlines :: String -> Meta -> [Inline] lookupMetaInlines key meta = case lookupMeta key meta of Just (MetaString s) -> [Str s] Just (MetaInlines ils) -> ils Just (MetaBlocks [Plain ils]) -> ils Just (MetaBlocks [Para ils]) -> ils _ -> [] -- | Retrieve the metadata value for a given @key@ -- and convert to String. lookupMetaString :: String -> Meta -> String lookupMetaString key meta = case lookupMeta key meta of Just (MetaString s) -> s Just (MetaInlines ils) -> stringify ils Just (MetaBlocks bs) -> stringify bs Just (MetaBool b) -> show b _ -> "" toSuperscript :: Char -> Maybe Char toSuperscript '1' = Just '\x00B9' toSuperscript '2' = Just '\x00B2' toSuperscript '3' = Just '\x00B3' toSuperscript '+' = Just '\x207A' toSuperscript '-' = Just '\x207B' toSuperscript '=' = Just '\x207C' toSuperscript '(' = Just '\x207D' toSuperscript ')' = Just '\x207E' toSuperscript c | c >= '0' && c <= '9' = Just $ chr (0x2070 + (ord c - 48)) | isSpace c = Just c | otherwise = Nothing toSubscript :: Char -> Maybe Char toSubscript '+' = Just '\x208A' toSubscript '-' = Just '\x208B' toSubscript '=' = Just '\x208C' toSubscript '(' = Just '\x208D' toSubscript ')' = Just '\x208E' toSubscript c | c >= '0' && c <= '9' = Just $ chr (0x2080 + (ord c - 48)) | isSpace c = Just c | otherwise = Nothing -- | Construct table of contents (as a bullet list) from document body. toTableOfContents :: WriterOptions -> [Block] -> Block toTableOfContents opts bs = BulletList $ map (elementToListItem opts) (hierarchicalize bs) -- | Converts an Element to a list item for a table of contents, elementToListItem :: WriterOptions -> Element -> [Block] elementToListItem opts (Sec lev _nums (ident,_,_) headerText subsecs) = Plain headerLink : [BulletList listContents | not (null subsecs) , lev < writerTOCDepth opts] where headerText' = walk deNote headerText headerLink = if null ident then headerText' else [Link nullAttr headerText' ('#':ident, "")] listContents = map (elementToListItem opts) subsecs elementToListItem _ (Blk _) = []