Data files changes.

* Added `embed_data_files` flag.  (not yet used)
* Shared no longer exports `findDataFile`.
* `readDataFile` now returns a strict bytestring.
* Shared now exports `readDataFileUTF8` which returns a string like
  the old `readDataFile`.
* Rewrote modules to use new data file functions and to avoid
  using functions from Paths_pandoc directly.

6 files changed, 41 insertions, 55 deletions

diff --git a/src/Text/Pandoc/SelfContained.hs b/src/Text/Pandoc/SelfContained.hs
index e468d504d..4b52a6f13 100644
--- a/src/Text/Pandoc/SelfContained.hs
+++ b/src/Text/Pandoc/SelfContained.hs
@@ -41,7 +41,7 @@ import System.FilePath (takeExtension, dropExtension, takeDirectory, (</>))
 import Data.Char (toLower, isAscii, isAlphaNum)
 import Codec.Compression.GZip as Gzip
 import qualified Data.ByteString.Lazy as L
-import Text.Pandoc.Shared (findDataFile, renderTags')
+import Text.Pandoc.Shared (readDataFile, renderTags')
 import Text.Pandoc.MIME (getMimeType)
 import System.Directory (doesFileExist)
 import Text.Pandoc.UTF8 (toString,  fromString)
@@ -55,18 +55,8 @@ getItem userdata f =
                       ".gz" -> getMimeType $ dropExtension f
                       x     -> getMimeType x
        exists <- doesFileExist f
-       if exists
-          then do
-            cont <- B.readFile f
-            return (cont, mime)
-          else do
-            res <- findDataFile userdata f
-            exists' <- doesFileExist res
-            if exists'
-               then do
-                 cont <- B.readFile res
-                 return (cont, mime)
-               else error $ "Could not find `" ++ f ++ "'"
+       cont <- if exists then B.readFile f else readDataFile userdata f
+       return (cont, mime)
 
 -- TODO - have this return mime type too - then it can work for google
 -- chart API, e.g.
diff --git a/src/Text/Pandoc/Shared.hs b/src/Text/Pandoc/Shared.hs
index dee10cf9b..71bdca9dd 100644
--- a/src/Text/Pandoc/Shared.hs
+++ b/src/Text/Pandoc/Shared.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE DeriveDataTypeable, CPP #-}
 {-
 Copyright (C) 2006-2010 John MacFarlane <jgm@berkeley.edu>
 
@@ -64,8 +64,8 @@ module Text.Pandoc.Shared (
                      renderTags',
                      -- * File handling
                      inDirectory,
-                     findDataFile,
                      readDataFile,
+                     readDataFileUTF8,
                      -- * Error handling
                      err,
                      warn,
@@ -89,13 +89,18 @@ import System.FilePath ( (</>) )
 import Data.Generics (Typeable, Data)
 import qualified Control.Monad.State as S
 import Control.Monad (msum)
-import Paths_pandoc (getDataFileName)
 import Text.Pandoc.Pretty (charWidth)
 import System.Locale (defaultTimeLocale)
 import Data.Time
 import System.IO (stderr)
 import Text.HTML.TagSoup (renderTagsOptions, RenderOptions(..), Tag(..),
          renderOptions)
+import qualified Data.ByteString as B
+#ifdef EMBED_DATA_FILES
+import Data.FileEmbed
+#else
+import Paths_pandoc (getDataFileName)
+#endif
 
 --
 -- List processing
@@ -499,20 +504,28 @@ inDirectory path action = do
   setCurrentDirectory oldDir
   return result
 
--- | Get file path for data file, either from specified user data directory,
--- or, if not found there, from Cabal data directory.
-findDataFile :: Maybe FilePath -> FilePath -> IO FilePath
-findDataFile Nothing f = getDataFileName f
-findDataFile (Just u) f = do
-  ex <- doesFileExist (u </> f)
-  if ex
-     then return (u </> f)
-     else getDataFileName f
+readDefaultDataFile :: FilePath -> IO B.ByteString
+readDefaultDataFile fname =
+#ifdef EMBED_DATA_FILES
+  TODO
+#else
+  getDataFileName fname >>= B.readFile
+#endif
 
 -- | Read file from specified user data directory or, if not found there, from
 -- Cabal data directory.
-readDataFile :: Maybe FilePath -> FilePath -> IO String
-readDataFile userDir fname = findDataFile userDir fname >>= UTF8.readFile
+readDataFile :: Maybe FilePath -> FilePath -> IO B.ByteString
+readDataFile Nothing fname = readDefaultDataFile fname
+readDataFile (Just userDir) fname = do
+  exists <- doesFileExist (userDir </> fname)
+  if exists
+     then B.readFile (userDir </> fname)
+     else readDefaultDataFile fname
+
+-- | Same as 'readDataFile' but returns a String instead of a ByteString.
+readDataFileUTF8 :: Maybe FilePath -> FilePath -> IO String
+readDataFileUTF8 userDir fname =
+  UTF8.toString `fmap` readDataFile userDir fname
 
 --
 -- Error reporting
diff --git a/src/Text/Pandoc/Templates.hs b/src/Text/Pandoc/Templates.hs
index 75c133101..bbdb4adc4 100644
--- a/src/Text/Pandoc/Templates.hs
+++ b/src/Text/Pandoc/Templates.hs
@@ -80,7 +80,7 @@ import Text.Blaze (preEscapedString, Html)
 #endif
 import Text.Pandoc.UTF8 (fromStringLazy)
 import Data.ByteString.Lazy (ByteString)
-import Text.Pandoc.Shared (readDataFile)
+import Text.Pandoc.Shared (readDataFileUTF8)
 import qualified Control.Exception.Extensible as E (try, IOException)
 
 -- | Get default template for the specified writer.
@@ -98,7 +98,7 @@ getDefaultTemplate user writer = do
        "multimarkdown"   -> getDefaultTemplate user "markdown"
        "markdown_github" -> getDefaultTemplate user "markdown"
        _        -> let fname = "templates" </> "default" <.> format
-                   in  E.try $ readDataFile user fname
+                   in  E.try $ readDataFileUTF8 user fname
 
 data TemplateState = TemplateState Int [(String,String)]
 
diff --git a/src/Text/Pandoc/Writers/Docx.hs b/src/Text/Pandoc/Writers/Docx.hs
index b0f31ac45..706ced967 100644
--- a/src/Text/Pandoc/Writers/Docx.hs
+++ b/src/Text/Pandoc/Writers/Docx.hs
@@ -29,14 +29,12 @@ Conversion of 'Pandoc' documents to docx.
 -}
 module Text.Pandoc.Writers.Docx ( writeDocx ) where
 import Data.List ( intercalate )
-import System.FilePath ( (</>) )
 import qualified Data.ByteString.Lazy as B
 import qualified Data.Map as M
 import qualified Text.Pandoc.UTF8 as UTF8
 import System.IO ( stderr )
 import Codec.Archive.Zip
 import Data.Time.Clock.POSIX
-import Paths_pandoc ( getDataFileName )
 import Text.Pandoc.Definition
 import Text.Pandoc.Generic
 import System.Directory
@@ -104,15 +102,8 @@ writeDocx opts doc@(Pandoc (Meta tit auths date) _) = do
   refArchive <- liftM toArchive $
        case writerReferenceDocx opts of
              Just f -> B.readFile f
-             Nothing -> do
-               let defaultDocx = getDataFileName "reference.docx" >>= B.readFile
-               case datadir of
-                     Nothing  -> defaultDocx
-                     Just d   -> do
-                        exists <- doesFileExist (d </> "reference.docx")
-                        if exists
-                           then B.readFile (d </> "reference.docx")
-                           else defaultDocx
+             Nothing -> (B.fromChunks . (:[])) `fmap`
+                          readDataFile datadir "reference.docx"
 
   (newContents, st) <- runStateT (writeOpenXML opts{writerWrapText = False} doc)
                        defaultWriterState
diff --git a/src/Text/Pandoc/Writers/EPUB.hs b/src/Text/Pandoc/Writers/EPUB.hs
index e7feace7a..4ffff0054 100644
--- a/src/Text/Pandoc/Writers/EPUB.hs
+++ b/src/Text/Pandoc/Writers/EPUB.hs
@@ -30,13 +30,13 @@ Conversion of 'Pandoc' documents to EPUB.
 module Text.Pandoc.Writers.EPUB ( writeEPUB2, writeEPUB3 ) where
 import Data.IORef
 import Data.Maybe ( fromMaybe, isNothing )
-import Data.List ( isPrefixOf, isInfixOf, intercalate )
+import Data.List ( isInfixOf, intercalate )
 import System.Environment ( getEnv )
 import Text.Printf (printf)
 import System.FilePath ( (</>), takeBaseName, takeExtension, takeFileName )
 import qualified Data.ByteString.Lazy as B
 import qualified Data.ByteString.Lazy.Char8 as B8
-import Text.Pandoc.UTF8 ( fromStringLazy )
+import Text.Pandoc.UTF8 ( fromStringLazy, toString )
 import Codec.Archive.Zip
 import Data.Time.Clock.POSIX
 import Data.Time
@@ -321,7 +321,8 @@ writeEPUB version opts doc@(Pandoc meta _) = do
   -- stylesheet
   stylesheet <- case writerEpubStylesheet opts of
                    Just s  -> return s
-                   Nothing -> readDataFile (writerUserDataDir opts) "epub.css"
+                   Nothing -> toString `fmap`
+                              readDataFile (writerUserDataDir opts) "epub.css"
   let stylesheetEntry = mkEntry "stylesheet.css" $ fromStringLazy stylesheet
 
   -- construct archive
diff --git a/src/Text/Pandoc/Writers/ODT.hs b/src/Text/Pandoc/Writers/ODT.hs
index cbff88be5..5e92cfcec 100644
--- a/src/Text/Pandoc/Writers/ODT.hs
+++ b/src/Text/Pandoc/Writers/ODT.hs
@@ -35,15 +35,13 @@ import qualified Data.ByteString.Lazy as B
 import Text.Pandoc.UTF8 ( fromStringLazy )
 import Codec.Archive.Zip
 import Data.Time.Clock.POSIX
-import Paths_pandoc ( getDataFileName )
 import Text.Pandoc.Options ( WriterOptions(..) )
-import Text.Pandoc.Shared ( stringify )
+import Text.Pandoc.Shared ( stringify, readDataFile )
 import Text.Pandoc.ImageSize ( readImageSize, sizeInPoints )
 import Text.Pandoc.MIME ( getMimeType )
 import Text.Pandoc.Definition
 import Text.Pandoc.Generic
 import Text.Pandoc.Writers.OpenDocument ( writeOpenDocument )
-import System.Directory
 import Control.Monad (liftM)
 import Network.URI ( unEscapeString )
 import Text.Pandoc.XML
@@ -59,15 +57,8 @@ writeODT opts doc@(Pandoc (Meta title _ _) _) = do
   refArchive <- liftM toArchive $
        case writerReferenceODT opts of
              Just f -> B.readFile f
-             Nothing -> do
-               let defaultODT = getDataFileName "reference.odt" >>= B.readFile
-               case datadir of
-                     Nothing  -> defaultODT
-                     Just d   -> do
-                        exists <- doesFileExist (d </> "reference.odt")
-                        if exists
-                           then B.readFile (d </> "reference.odt")
-                           else defaultODT
+             Nothing -> (B.fromChunks . (:[])) `fmap`
+                           readDataFile datadir "reference.odt"
   -- handle pictures
   picEntriesRef <- newIORef ([] :: [Entry])
   let sourceDir = writerSourceDirectory opts