    {-# LANGUAGE ScopedTypeVariables #-}
    {-
    Copyright (C) 2008-2015 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.ODT
       Copyright   : Copyright (C) 2008-2015 John MacFarlane
       License     : GNU GPL, version 2 or above

       Maintainer  : John MacFarlane <jgm@berkeley.edu>
       Stability   : alpha
       Portability : portable

    Conversion of 'Pandoc' documents to ODT.
    -}
    module Text.Pandoc.Writers.ODT ( writeODT ) where
    import Data.IORef
    import Data.List ( isPrefixOf )
    import Data.Maybe ( fromMaybe )
    import Text.XML.Light.Output
    import Text.TeXMath
    import qualified Data.ByteString.Lazy as B
    import Text.Pandoc.UTF8 ( fromStringLazy )
    import Codec.Archive.Zip
    import Text.Pandoc.Options ( WriterOptions(..), WrapOption(..) )
    import Text.Pandoc.Shared ( stringify, fetchItem', warn,
                                getDefaultReferenceODT )
    import Text.Pandoc.ImageSize
    import Text.Pandoc.MIME ( getMimeType, extensionFromMimeType )
    import Text.Pandoc.Definition
    import Text.Pandoc.Walk
    import Text.Pandoc.Writers.Shared ( fixDisplayMath )
    import Text.Pandoc.Writers.OpenDocument ( writeOpenDocument )
    import Control.Monad (liftM)
    import Text.Pandoc.XML
    import Text.Pandoc.Pretty
    import qualified Control.Exception as E
    import Data.Time.Clock.POSIX ( getPOSIXTime )
    import System.FilePath ( takeExtension, takeDirectory, (<.>))

    -- | Produce an ODT file from a Pandoc document.
    writeODT :: WriterOptions  -- ^ Writer options
             -> Pandoc         -- ^ Document to convert
             -> IO B.ByteString
    writeODT opts doc@(Pandoc meta _) = do
      let datadir = writerUserDataDir opts
      let title = docTitle meta
      refArchive <-
           case writerReferenceODT opts of
                 Just f -> liftM toArchive $ B.readFile f
                 Nothing -> getDefaultReferenceODT datadir
      -- handle formulas and pictures
      picEntriesRef <- newIORef ([] :: [Entry])
      doc' <- walkM (transformPicMath opts picEntriesRef) $ walk fixDisplayMath doc
      let newContents = writeOpenDocument opts{writerWrapText = WrapNone} doc'
      epochtime <- floor `fmap` getPOSIXTime
      let contentEntry = toEntry "content.xml" epochtime
                         $ fromStringLazy newContents
      picEntries <- readIORef picEntriesRef
      let archive = foldr addEntryToArchive refArchive
                    $ contentEntry : picEntries
      -- construct META-INF/manifest.xml based on archive
      let toFileEntry fp = case getMimeType fp of
                            Nothing  -> empty
                            Just m   -> selfClosingTag "manifest:file-entry"
                                         [("manifest:media-type", m)
                                         ,("manifest:full-path", fp)
                                         ,("manifest:version", "1.2")
                                         ]
      let files = [ ent | ent <- filesInArchive archive,
                                 not ("META-INF" `isPrefixOf` ent) ]
      let formulas = [ takeDirectory ent ++ "/" | ent <- filesInArchive archive,
                          "Formula-" `isPrefixOf` ent, takeExtension ent == ".xml" ]
      let manifestEntry = toEntry "META-INF/manifest.xml" epochtime
            $ fromStringLazy $ render Nothing
            $ text "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
            $$
             ( inTags True "manifest:manifest"
                [("xmlns:manifest","urn:oasis:names:tc:opendocument:xmlns:manifest:1.0")
                ,("manifest:version","1.2")]
                $ ( selfClosingTag "manifest:file-entry"
                     [("manifest:media-type","application/vnd.oasis.opendocument.text")
                     ,("manifest:full-path","/")]
                    $$ vcat ( map toFileEntry $ files )
                    $$ vcat ( map toFileEntry $ formulas )
                  )
             )
      let archive' = addEntryToArchive manifestEntry archive
      let metaEntry = toEntry "meta.xml" epochtime
           $ fromStringLazy $ render Nothing
           $ text "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
           $$
            ( inTags True "office:document-meta"
               [("xmlns:office","urn:oasis:names:tc:opendocument:xmlns:office:1.0")
               ,("xmlns:xlink","http://www.w3.org/1999/xlink")
               ,("xmlns:dc","http://purl.org/dc/elements/1.1/")
               ,("xmlns:meta","urn:oasis:names:tc:opendocument:xmlns:meta:1.0")
               ,("xmlns:ooo","http://openoffice.org/2004/office")
               ,("xmlns:grddl","http://www.w3.org/2003/g/data-view#")
               ,("office:version","1.2")]
               $ ( inTagsSimple "office:meta"
                    $ ( inTagsSimple "dc:title" (text $ escapeStringForXML (stringify title))
                      )
                 )
            )
      -- make sure mimetype is first
      let mimetypeEntry = toEntry "mimetype" epochtime
                          $ fromStringLazy "application/vnd.oasis.opendocument.text"
      let archive'' = addEntryToArchive mimetypeEntry
                      $ addEntryToArchive metaEntry archive'
      return $ fromArchive archive''

    -- | transform both Image and Math elements
    transformPicMath :: WriterOptions -> IORef [Entry] -> Inline -> IO Inline
    transformPicMath opts entriesRef (Image attr@(id', cls, _) lab (src,t)) = do
      res <- fetchItem' (writerMediaBag opts) (writerSourceURL opts) src
      case res of
         Left (_ :: E.SomeException) -> do
           warn $ "Could not find image `" ++ src ++ "', skipping..."
           return $ Emph lab
         Right (img, mbMimeType) -> do
           (ptX, ptY) <- case imageSize img of
                           Right s  -> return $ sizeInPoints s
                           Left msg -> do
                             warn $ "Could not determine image size in `" ++
                               src ++ "': " ++ msg
                             return (100, 100)
           let dims =
                 case (getDim Width, getDim Height) of
                   (Just w, Just h)              -> [("width", show w), ("height", show h)]
                   (Just w@(Percent _), Nothing) -> [("width", show w), ("style:rel-height", "scale")]
                   (Nothing, Just h@(Percent _)) -> [("style:rel-width", "scale"), ("height", show h)]
                   (Just w@(Inch i), Nothing)    -> [("width", show w), ("height", show (i / ratio) ++ "in")]
                   (Nothing, Just h@(Inch i))    -> [("width", show (i * ratio) ++ "in"), ("height", show h)]
                   _                             -> [("width", show ptX ++ "pt"), ("height", show ptY ++ "pt")]
                 where
                   ratio = ptX / ptY
                   getDim dir = case (dimension dir attr) of
                                  Just (Percent i) -> Just $ Percent i
                                  Just dim         -> Just $ Inch $ inInch opts dim
                                  Nothing          -> Nothing
           let  newattr = (id', cls, dims)
           entries <- readIORef entriesRef
           let extension = fromMaybe (takeExtension $ takeWhile (/='?') src)
                               (mbMimeType >>= extensionFromMimeType)
           let newsrc = "Pictures/" ++ show (length entries) <.> extension
           let toLazy = B.fromChunks . (:[])
           epochtime <- floor `fmap` getPOSIXTime
           let entry = toEntry newsrc epochtime $ toLazy img
           modifyIORef entriesRef (entry:)
           return $ Image newattr lab (newsrc, t)
    transformPicMath _ entriesRef (Math t math) = do
      entries <- readIORef entriesRef
      let dt = if t == InlineMath then DisplayInline else DisplayBlock
      case writeMathML dt <$> readTeX math of
           Left  _ -> return $ Math t math
           Right r -> do
             let conf = useShortEmptyTags (const False) defaultConfigPP
             let mathml = ppcTopElement conf r
             epochtime <- floor `fmap` getPOSIXTime
             let dirname = "Formula-" ++ show (length entries) ++ "/"
             let fname = dirname ++ "content.xml"
             let entry = toEntry fname epochtime (fromStringLazy mathml)
             modifyIORef entriesRef (entry:)
             return $ RawInline (Format "opendocument") $ render Nothing $
               inTags False "draw:frame" [("text:anchor-type",
                                           if t == DisplayMath
                                              then "paragraph"
                                              else "as-char")
                                         ,("style:vertical-pos", "middle")
                                         ,("style:vertical-rel", "text")] $
                 selfClosingTag "draw:object" [("xlink:href", dirname)
                                            , ("xlink:type", "simple")
                                            , ("xlink:show", "embed")
                                            , ("xlink:actuate", "onLoad")]

    transformPicMath _ _ x = return x