Options.WriterOptions: Change type of writerVariables to Context Text.

This will allow structured values.

[API change]

10 files changed, 126 insertions, 49 deletions

diff --git a/src/Text/Pandoc/App/OutputSettings.hs b/src/Text/Pandoc/App/OutputSettings.hs
index 04ea89eda..264eb4a65 100644
--- a/src/Text/Pandoc/App/OutputSettings.hs
+++ b/src/Text/Pandoc/App/OutputSettings.hs
@@ -20,6 +20,9 @@ module Text.Pandoc.App.OutputSettings
   ) where
 import Prelude
 import qualified Control.Exception as E
+import qualified Data.Text as T
+import qualified Data.Map as M
+import Text.DocTemplates (Context(..), ToContext(toVal))
 import Control.Monad
 import Control.Monad.Except (catchError, throwError)
 import Control.Monad.Trans
@@ -159,6 +162,8 @@ optToOutputSettings opts = do
                                  $ lines dztempl
                       return $ ("dzslides-core", dzcore) : vars
                   else return vars)
+    >>= fmap (Context . M.fromList) .
+          traverse (\(x,y) -> return (T.pack x, toVal (T.pack y)))
 
   templStr <- case optTemplate opts of
                   _ | not standalone -> return Nothing
diff --git a/src/Text/Pandoc/BCP47.hs b/src/Text/Pandoc/BCP47.hs
index f783c0320..ce8aa99ca 100644
--- a/src/Text/Pandoc/BCP47.hs
+++ b/src/Text/Pandoc/BCP47.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 {- |
    Module      : Text.Pandoc.BCP47
@@ -24,6 +25,8 @@ import Data.Char (isAlphaNum, isAscii, isLetter, isLower, isUpper, toLower,
 import Data.List (intercalate)
 import Text.Pandoc.Definition
 import Text.Pandoc.Options
+import Text.DocTemplates (FromContext(..))
+import qualified Data.Text as T
 import qualified Text.Parsec as P
 
 -- | Represents BCP 47 language/country code.
@@ -41,8 +44,8 @@ renderLang lang = intercalate "-" (langLanguage lang : filter (not . null)
 -- | Get the contents of the `lang` metadata field or variable.
 getLang :: WriterOptions -> Meta -> Maybe String
 getLang opts meta =
-  case lookup "lang" (writerVariables opts) of
-        Just s -> Just s
+  case lookupContext "lang" (writerVariables opts) of
+        Just s -> Just $ T.unpack s
         _      ->
           case lookupMeta "lang" meta of
                Just (MetaInlines [Str s]) -> Just s
diff --git a/src/Text/Pandoc/Lua/Marshaling.hs b/src/Text/Pandoc/Lua/Marshaling.hs
index 8a1270ab7..c37f22b8d 100644
--- a/src/Text/Pandoc/Lua/Marshaling.hs
+++ b/src/Text/Pandoc/Lua/Marshaling.hs
@@ -14,4 +14,5 @@ module Text.Pandoc.Lua.Marshaling () where
 import Text.Pandoc.Lua.Marshaling.AST ()
 import Text.Pandoc.Lua.Marshaling.CommonState ()
 import Text.Pandoc.Lua.Marshaling.ReaderOptions ()
+import Text.Pandoc.Lua.Marshaling.Context ()
 import Text.Pandoc.Lua.Marshaling.Version ()
diff --git a/src/Text/Pandoc/Lua/Marshaling/Context.hs b/src/Text/Pandoc/Lua/Marshaling/Context.hs
new file mode 100644
index 000000000..a9cc7f38e
--- /dev/null
+++ b/src/Text/Pandoc/Lua/Marshaling/Context.hs
@@ -0,0 +1,31 @@
+{-# LANGUAGE NoImplicitPrelude    #-}
+{-# LANGUAGE FlexibleInstances    #-}
+{-# LANGUAGE ScopedTypeVariables  #-}
+{-# LANGUAGE LambdaCase           #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+{- |
+   Module      : Text.Pandoc.Lua.Marshaling.Context
+   Copyright   : © 2012-2019 John MacFarlane
+                 © 2017-2019 Albert Krewinkel
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+   Stability   : alpha
+
+Marshaling instance for doctemplates Context and its components.
+-}
+module Text.Pandoc.Lua.Marshaling.Context () where
+
+import qualified Foreign.Lua as Lua
+import Foreign.Lua (Pushable)
+import Text.DocTemplates (Context(..), Val(..))
+
+instance Pushable a => Pushable (Context a) where
+  push (Context m) = Lua.push m
+
+instance Pushable a => Pushable (Val a) where
+  push NullVal = Lua.push ()
+  push (MapVal ctx) = Lua.push ctx
+  push (ListVal xs) = Lua.push xs
+  push (SimpleVal x) = Lua.push x
+
diff --git a/src/Text/Pandoc/Options.hs b/src/Text/Pandoc/Options.hs
index 59546cd1b..5dc94b2ad 100644
--- a/src/Text/Pandoc/Options.hs
+++ b/src/Text/Pandoc/Options.hs
@@ -34,6 +34,8 @@ import Prelude
 import Data.Char (toLower)
 import Data.Data (Data)
 import Data.Default
+import Data.Text (Text)
+import Text.DocTemplates (Context(..))
 import qualified Data.Set as Set
 import Data.Typeable (Typeable)
 import GHC.Generics (Generic)
@@ -148,7 +150,7 @@ data ReferenceLocation = EndOfBlock    -- ^ End of block
 -- | Options for writers
 data WriterOptions = WriterOptions
   { writerTemplate          :: Maybe Template -- ^ Template to use
-  , writerVariables         :: [(String, String)] -- ^ Variables to set in template
+  , writerVariables         :: Context Text -- ^ Variables to set in template
   , writerTabStop           :: Int    -- ^ Tabstop for conversion btw spaces and tabs
   , writerTableOfContents   :: Bool   -- ^ Include table of contents
   , writerIncremental       :: Bool   -- ^ True if lists should be incremental
@@ -185,7 +187,7 @@ data WriterOptions = WriterOptions
 
 instance Default WriterOptions where
   def = WriterOptions { writerTemplate         = Nothing
-                      , writerVariables        = []
+                      , writerVariables        = mempty
                       , writerTabStop          = 4
                       , writerTableOfContents  = False
                       , writerIncremental      = False
diff --git a/src/Text/Pandoc/Writers/EPUB.hs b/src/Text/Pandoc/Writers/EPUB.hs
index dfcb8e215..ef7ce659b 100644
--- a/src/Text/Pandoc/Writers/EPUB.hs
+++ b/src/Text/Pandoc/Writers/EPUB.hs
@@ -2,6 +2,7 @@
 {-# LANGUAGE CPP                 #-}
 {-# LANGUAGE FlexibleContexts    #-}
 {-# LANGUAGE PatternGuards       #-}
+{-# LANGUAGE OverloadedStrings   #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {- |
    Module      : Text.Pandoc.Writers.EPUB
@@ -58,6 +59,8 @@ import Text.XML.Light (Attr (..), Element (..), Node (..), QName (..),
                        add_attrs, lookupAttr, node, onlyElems, parseXML,
                        ppElement, showElement, strContent, unode, unqual)
 import Text.Pandoc.XML (escapeStringForXML)
+import Text.DocTemplates (FromContext(lookupContext), Context(..),
+                          ToContext(toVal), Val(..))
 
 -- A Chapter includes a list of blocks.
 data Chapter = Chapter [Block]
@@ -136,6 +139,9 @@ removeNote :: Inline -> Inline
 removeNote (Note _) = Str ""
 removeNote x        = x
 
+toVal' :: String -> Val TS.Text
+toVal' = toVal . TS.pack
+
 mkEntry :: PandocMonad m => FilePath -> B.ByteString -> E m Entry
 mkEntry path content = do
   epubSubdir <- gets stEpubSubdir
@@ -163,8 +169,8 @@ getEPUBMetadata opts meta = do
           else return m
   let addLanguage m =
        if null (epubLanguage m)
-          then case lookup "lang" (writerVariables opts) of
-                     Just x  -> return m{ epubLanguage = x }
+          then case lookupContext "lang" (writerVariables opts) of
+                     Just x  -> return m{ epubLanguage = TS.unpack x }
                      Nothing -> do
                        mLang <- lift $ P.lookupEnv "LANG"
                        let localeLang =
@@ -345,11 +351,14 @@ metadataFromMeta opts meta = EPUBMetadata{
         relation = metaValueToString <$> lookupMeta "relation" meta
         coverage = metaValueToString <$> lookupMeta "coverage" meta
         rights = metaValueToString <$> lookupMeta "rights" meta
-        coverImage = lookup "epub-cover-image" (writerVariables opts) `mplus`
-             (metaValueToString <$> lookupMeta "cover-image" meta)
+        coverImage =
+            (TS.unpack <$> lookupContext "epub-cover-image"
+                              (writerVariables opts))
+            `mplus` (metaValueToString <$> lookupMeta "cover-image" meta)
         mCss = lookupMeta "css" meta <|> lookupMeta "stylesheet" meta
         stylesheets = fromMaybe [] (metaValueToPaths <$> mCss) ++
-                        [f | ("css",f) <- writerVariables opts]
+                      maybe [] (\t -> [TS.unpack t])
+                        (lookupContext "css" (writerVariables opts))
         pageDirection = case map toLower . metaValueToString <$>
                              lookupMeta "page-progression-direction" meta of
                               Just "ltr" -> Just LTR
@@ -424,10 +433,13 @@ pandocToEPUB version opts doc = do
         (\bs n -> mkEntry ("styles/stylesheet" ++ show n ++ ".css") bs)
         stylesheets [(1 :: Int)..]
 
-  let vars = ("epub3", if epub3 then "true" else "false")
-             : [(x,y) | (x,y) <- writerVariables opts, x /= "css"]
+  let vars = Context $
+             M.delete "css" . M.insert "epub3"
+                 (toVal' $ if epub3 then "true" else "false") $
+             unContext $ writerVariables opts
 
-  let cssvars useprefix = map (\e -> ("css",
+  let cssvars useprefix = Context $ M.fromList $ map
+                       (\e -> ("css", toVal' $
                                (if useprefix
                                    then "../"
                                    else "")
@@ -457,14 +469,16 @@ pandocToEPUB version opts doc = do
                                  (CouldNotDetermineImageSize img err')
                        cpContent <- lift $ writeHtml
                             opts'{ writerVariables =
-                                    ("coverpage","true"):
-                                    ("pagetitle",
-                                       escapeStringForXML plainTitle):
-                                    ("cover-image", coverImage):
-                                    ("cover-image-width", show coverImageWidth):
-                                    ("cover-image-height",
-                                       show coverImageHeight):
-                                     cssvars True ++ vars }
+                                   Context (M.fromList [
+                                    ("coverpage", toVal' "true"),
+                                    ("pagetitle", toVal' $
+                                      escapeStringForXML plainTitle),
+                                    ("cover-image", toVal' coverImage),
+                                    ("cover-image-width", toVal' $
+                                       show coverImageWidth),
+                                    ("cover-image-height", toVal' $
+                                       show coverImageHeight)]) <>
+                                     cssvars True <> vars }
                             (Pandoc meta [])
                        coverEntry <- mkEntry "text/cover.xhtml" cpContent
                        coverImageEntry <- mkEntry ("media/" ++ coverImage)
@@ -474,10 +488,13 @@ pandocToEPUB version opts doc = do
 
   -- title page
   tpContent <- lift $ writeHtml opts'{
-                                  writerVariables = ("titlepage","true"):
-                                  ("body-type", "frontmatter"):
-                                  ("pagetitle", escapeStringForXML plainTitle):
-                                  cssvars True ++ vars }
+                                  writerVariables =
+                                      Context (M.fromList [
+                                        ("titlepage", toVal' "true"),
+                                        ("body-type",  toVal' "frontmatter"),
+                                        ("pagetitle", toVal' $
+                                            escapeStringForXML plainTitle)])
+                                      <> cssvars True <> vars }
                                (Pandoc meta [])
   tpEntry <- mkEntry "text/title_page.xhtml" tpContent
 
@@ -564,9 +581,12 @@ pandocToEPUB version opts doc = do
 
   let chapToEntry num (Chapter bs) =
         mkEntry ("text/" ++ showChapter num) =<<
-        writeHtml opts'{ writerVariables = ("body-type", bodyType) :
-                                            ("pagetitle", showChapter num) :
-                                             cssvars True ++ vars } pdoc
+        writeHtml opts'{ writerVariables =
+                            Context (M.fromList
+                                     [("body-type", toVal' bodyType),
+                                      ("pagetitle", toVal' $
+                                           showChapter num)])
+                            <> cssvars True <> vars } pdoc
          where (pdoc, bodyType) =
                  case bs of
                      (Header _ (_,_,kvs) xs : _) ->
@@ -776,9 +796,10 @@ pandocToEPUB version opts doc = do
                                (writeHtmlStringForEPUB version
                                  opts{ writerTemplate = Nothing
                                      , writerVariables =
-                                       ("pagetitle",
-                                         escapeStringForXML plainTitle):
-                                       writerVariables opts}
+                                         Context (M.fromList
+                                           [("pagetitle", toVal' $
+                                             escapeStringForXML plainTitle)])
+                                       <> writerVariables opts}
                                  (Pandoc nullMeta
                                    [Plain $ walk clean tit])) of
                                 Left _  -> TS.pack $ stringify tit
@@ -801,13 +822,13 @@ pandocToEPUB version opts doc = do
                          then [ unode "li"
                                 [ unode "a" ! [("href", "text/cover.xhtml")
                                               ,("epub:type", "cover")] $
-                                  "Cover"] |
+                                  ("Cover" :: String)] |
                                   isJust (epubCoverImage metadata)
                               ] ++
                               [ unode "li"
                                 [ unode "a" ! [("href", "#toc")
                                               ,("epub:type", "toc")] $
-                                    "Table of contents"
+                                    ("Table of contents" :: String)
                                 ] | writerTableOfContents opts
                               ]
                          else []
@@ -819,8 +840,9 @@ pandocToEPUB version opts doc = do
                                           ,("hidden","hidden")] $
                             [ unode "ol" landmarkItems ]
                           ]
-  navData <- lift $ writeHtml opts'{ writerVariables = ("navpage","true"):
-                     cssvars False ++ vars }
+  navData <- lift $ writeHtml opts'{ writerVariables =
+                     Context (M.fromList [("navpage", toVal' "true")])
+                     <> cssvars False <> vars }
             (Pandoc (setMeta "title"
                      (walk removeNote $ fromList $ docTitle' meta) nullMeta)
                (navBlocks ++ landmarks))
@@ -846,7 +868,7 @@ pandocToEPUB version opts doc = do
   let apple = UTF8.fromStringLazy $ ppTopElement $
         unode "display_options" $
           unode "platform" ! [("name","*")] $
-            unode "option" ! [("name","specified-fonts")] $ "true"
+            unode "option" ! [("name","specified-fonts")] $ ("true" :: String)
   appleEntry <- mkEntry "META-INF/com.apple.ibooks.display-options.xml" apple
 
   -- construct archive
@@ -949,6 +971,7 @@ metadataElement version md currentTime =
              (("id",id') :
                 maybe [] (\x -> [("opf:event",x)]) (dateEvent date)) $
                  dateText date]
+        schemeToOnix :: String -> String
         schemeToOnix "ISBN-10"              = "02"
         schemeToOnix "GTIN-13"              = "03"
         schemeToOnix "UPC"                  = "04"
diff --git a/src/Text/Pandoc/Writers/HTML.hs b/src/Text/Pandoc/Writers/HTML.hs
index c74d677e0..d7a7e19ea 100644
--- a/src/Text/Pandoc/Writers/HTML.hs
+++ b/src/Text/Pandoc/Writers/HTML.hs
@@ -39,6 +39,7 @@ import Data.List.Split (splitWhen)
 import Data.Text (Text)
 import qualified Data.Text as T
 import qualified Data.Text.Lazy as TL
+import Text.DocTemplates (FromContext(lookupContext))
 import Network.HTTP (urlEncode)
 import Network.URI (URI (..), parseURIReference)
 import Numeric (showHex)
@@ -220,8 +221,8 @@ writeHtmlString' st opts d = do
             case getField "pagetitle" context of
                  Just (s :: Text) | not (T.null s) -> return context
                  _ -> do
-                   let fallback = maybe "Untitled" takeBaseName $
-                           lookup "sourcefile" (writerVariables opts)
+                   let fallback = maybe "Untitled" (takeBaseName . T.unpack) $
+                           lookupContext "sourcefile" (writerVariables opts)
                    report $ NoTitleElement fallback
                    return $ resetField "pagetitle" (T.pack fallback) context
          return $ renderTemplate tpl
@@ -286,11 +287,13 @@ pandocToHtml opts (Pandoc meta blocks) = do
                          H.link ! A.rel "stylesheet" !
                            A.href (toValue $ url ++ "katex.min.css")
 
-                      _ -> case lookup "mathml-script" (writerVariables opts) of
+                      _ -> case lookupContext "mathml-script"
+                                (writerVariables opts) of
                                  Just s | not (stHtml5 st) ->
                                    H.script ! A.type_ "text/javascript"
                                       $ preEscapedString
-                                       ("/*<![CDATA[*/\n" ++ s ++ "/*]]>*/\n")
+                                       ("/*<![CDATA[*/\n" ++ T.unpack s ++
+                                       "/*]]>*/\n")
                                         | otherwise -> mempty
                                  Nothing -> mempty
   let context =   (if stHighlighting st
diff --git a/src/Text/Pandoc/Writers/LaTeX.hs b/src/Text/Pandoc/Writers/LaTeX.hs
index 2ea26344a..81a3082cb 100644
--- a/src/Text/Pandoc/Writers/LaTeX.hs
+++ b/src/Text/Pandoc/Writers/LaTeX.hs
@@ -30,6 +30,7 @@ import qualified Data.Map as M
 import Data.Text (Text)
 import qualified Data.Text as T
 import Network.URI (unEscapeString)
+import Text.DocTemplates (FromContext(lookupContext))
 import Text.Pandoc.BCP47 (Lang (..), getLang, renderLang)
 import Text.Pandoc.Class (PandocMonad, report, toLang)
 import Text.Pandoc.Definition
@@ -146,8 +147,9 @@ pandocToLaTeX options (Pandoc meta blocks) = do
   -- these have \frontmatter etc.
   beamer <- gets stBeamer
   let documentClass =
-        case lookup "documentclass" (writerVariables options) `mplus`
-              fmap stringify (lookupMeta "documentclass" meta) of
+        case (lookupContext "documentclass"
+                  (writerVariables options)) `mplus`
+              (T.pack . stringify <$> lookupMeta "documentclass" meta) of
                  Just x -> x
                  Nothing | beamer    -> "beamer"
                          | otherwise -> case writerTopLevelDivision options of
@@ -208,7 +210,7 @@ pandocToLaTeX options (Pandoc meta blocks) = do
                   defField "title-meta" (T.pack titleMeta) $
                   defField "author-meta"
                         (T.pack $ intercalate "; " authorsMeta) $
-                  defField "documentclass" (T.pack documentClass) $
+                  defField "documentclass" documentClass $
                   defField "verbatim-in-note" (stVerbInNote st) $
                   defField "tables" (stTable st) $
                   defField "strikeout" (stStrikeout st) $
diff --git a/src/Text/Pandoc/Writers/Powerpoint/Output.hs b/src/Text/Pandoc/Writers/Powerpoint/Output.hs
index 6b43fa34a..58f230a9d 100644
--- a/src/Text/Pandoc/Writers/Powerpoint/Output.hs
+++ b/src/Text/Pandoc/Writers/Powerpoint/Output.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 {-# LANGUAGE PatternGuards #-}
 {- |
@@ -24,6 +25,7 @@ import Codec.Archive.Zip
 import Data.Char (toUpper)
 import Data.List (intercalate, stripPrefix, nub, union, isPrefixOf, intersperse)
 import Data.Default
+import qualified Data.Text as T
 import Data.Time (formatTime, defaultTimeLocale)
 import Data.Time.Clock (UTCTime)
 import Data.Time.Clock.POSIX (utcTimeToPOSIXSeconds, posixSecondsToUTCTime)
@@ -43,6 +45,7 @@ import Data.Maybe (mapMaybe, listToMaybe, fromMaybe, maybeToList, catMaybes, isN
 import Text.Pandoc.ImageSize
 import Control.Applicative ((<|>))
 import System.FilePath.Glob
+import Text.DocTemplates (FromContext(lookupContext))
 import Text.TeXMath
 import Text.Pandoc.Writers.Math (convertMath)
 import Text.Pandoc.Writers.Powerpoint.Presentation
@@ -159,8 +162,8 @@ runP env st p = evalStateT (runReaderT p env) st
 monospaceFont :: Monad m => P m String
 monospaceFont = do
   vars <- writerVariables <$> asks envOpts
-  case lookup "monofont" vars of
-    Just s -> return s
+  case lookupContext "monofont" vars of
+    Just s -> return (T.unpack s)
     Nothing -> return "Courier"
 
 fontSizeAttributes :: Monad m => RunProps -> P m [(String, String)]
diff --git a/src/Text/Pandoc/Writers/Shared.hs b/src/Text/Pandoc/Writers/Shared.hs
index 7d4a496f2..c294eeebb 100644
--- a/src/Text/Pandoc/Writers/Shared.hs
+++ b/src/Text/Pandoc/Writers/Shared.hs
@@ -39,6 +39,7 @@ module Text.Pandoc.Writers.Shared (
 where
 import Prelude
 import Safe (lastMay)
+import qualified Data.ByteString.Lazy as BL
 import Data.Maybe (fromMaybe)
 import Control.Monad (zipWithM)
 import Data.Aeson (ToJSON (..), encode)
@@ -90,12 +91,15 @@ metaToContext' blockWriter inlineWriter (Meta metamap) = do
 -- | Add variables to a template Context, replacing any existing values.
 addVariablesToContext :: TemplateTarget a
                       => WriterOptions -> Context a -> Context a
-addVariablesToContext opts (Context m1) = Context (m1 `M.union` m2)
+addVariablesToContext opts (Context m1) =
+  Context (m1 `M.union` m2 `M.union` m3)
  where
-   m2 = M.fromList $ map (\(k,v)
-                           -> (T.pack k,SimpleVal (fromText (T.pack v)))) $
-           ("meta-json", jsonrep) : writerVariables opts
-   jsonrep = UTF8.toStringLazy $ encode $ toJSON m1
+   m2 = case traverse go (writerVariables opts) of
+                  Just (Context x) -> x
+                  Nothing -> mempty
+   m3 = M.insert "meta-json" (SimpleVal $ fromText jsonrep) mempty
+   go = Just . fromText
+   jsonrep = UTF8.toText $ BL.toStrict $ encode $ toJSON m1
 
 metaValueToVal :: (Monad m, TemplateTarget a)
                => ([Block] -> m a)