Added Text.Pandoc.Readers.OPML, exporting readOPML.

The _note attribute is supported.  This is unofficial, but
used e.g. in OmniOutliner and supported by multimarkdown.
We treat the contents as markdown blocks under a section
header.

Added to documentation and tests.

8 files changed, 268 insertions, 4 deletions

diff --git a/README b/README
index 39c69d08f..a6602718a 100644
--- a/README
+++ b/README
@@ -13,8 +13,8 @@ Description
 Pandoc is a [Haskell] library for converting from one markup format to
 another, and a command-line tool that uses this library. It can read
 [markdown] and (subsets of) [Textile], [reStructuredText], [HTML],
-[LaTeX], [MediaWiki markup], and [DocBook XML]; and it can write plain
-text, [markdown], [reStructuredText], [XHTML], [HTML 5], [LaTeX]
+[LaTeX], [MediaWiki markup], [OPML], and [DocBook XML]; and it can write
+plain text, [markdown], [reStructuredText], [XHTML], [HTML 5], [LaTeX]
 (including [beamer] slide shows), [ConTeXt], [RTF], [DocBook XML],
 [OpenDocument XML], [ODT], [Word docx], [GNU Texinfo], [MediaWiki
 markup], [EPUB] (v2 or v3), [FictionBook2], [Textile], [groff man] pages, [Emacs
@@ -143,7 +143,7 @@ General options
     `markdown_phpextra` (PHP Markdown Extra extended markdown),
     `markdown_github` (github extended markdown),
     `textile` (Textile), `rst` (reStructuredText), `html` (HTML),
-    `docbook` (DocBook XML), `mediawiki` (MediaWiki markup),
+    `docbook` (DocBook XML), `opml` (OPML), `mediawiki` (MediaWiki markup),
     or `latex` (LaTeX). If `+lhs` is appended to `markdown`, `rst`,
     `latex`, the input will be treated as literate Haskell source:
     see [Literate Haskell support](#literate-haskell-support), below.
@@ -2624,6 +2624,7 @@ Sergey Astanin, Arlo O'Keeffe, Denis Laxalde, Brent Yorgey.
 [ConTeXt]: http://www.pragma-ade.nl/
 [RTF]:  http://en.wikipedia.org/wiki/Rich_Text_Format
 [DocBook XML]:  http://www.docbook.org/
+[OPML]: http://dev.opml.org/spec2.html
 [OpenDocument XML]: http://opendocument.xml.org/
 [ODT]: http://en.wikipedia.org/wiki/OpenDocument
 [Textile]: http://redcloth.org/textile
diff --git a/pandoc.cabal b/pandoc.cabal
index 7f82d11a1..c53e29838 100644
--- a/pandoc.cabal
+++ b/pandoc.cabal
@@ -16,7 +16,7 @@ Synopsis:        Conversion between markup formats
 Description:     Pandoc is a Haskell library for converting from one markup
                  format to another, and a command-line tool that uses
                  this library. It can read markdown and (subsets of) HTML,
-                 reStructuredText, LaTeX, DocBook, MediaWiki markup,
+                 reStructuredText, LaTeX, DocBook, MediaWiki markup, OPML,
                  and Textile, and it can write markdown, reStructuredText,
                  HTML, LaTeX, ConTeXt, Docbook, OpenDocument, ODT,
                  Word docx, RTF, MediaWiki, Textile, groff man pages,
@@ -105,6 +105,8 @@ Extra-Source-Files:
                  tests/docbook-reader.native
                  tests/html-reader.html,
                  tests/html-reader.native,
+                 tests/opml-reader.html,
+                 tests/opml-reader.native,
                  tests/insert,
                  tests/lalune.jpg,
                  tests/movie.jpg,
@@ -278,6 +280,7 @@ Library
                    Text.Pandoc.Readers.MediaWiki,
                    Text.Pandoc.Readers.RST,
                    Text.Pandoc.Readers.DocBook,
+                   Text.Pandoc.Readers.OPML,
                    Text.Pandoc.Readers.TeXMath,
                    Text.Pandoc.Readers.Textile,
                    Text.Pandoc.Readers.Native,
diff --git a/pandoc.hs b/pandoc.hs
index de132b0c8..8433460b3 100644
--- a/pandoc.hs
+++ b/pandoc.hs
@@ -758,6 +758,7 @@ defaultReaderName fallback (x:xs) =
     ".rst"      -> "rst"
     ".lhs"      -> "markdown+lhs"
     ".db"       -> "docbook"
+    ".opml"     -> "opml"
     ".wiki"     -> "mediawiki"
     ".textile"  -> "textile"
     ".native"   -> "native"
diff --git a/src/Text/Pandoc.hs b/src/Text/Pandoc.hs
index 8201bc881..80ddb72d7 100644
--- a/src/Text/Pandoc.hs
+++ b/src/Text/Pandoc.hs
@@ -72,6 +72,7 @@ module Text.Pandoc
                , readHtml
                , readTextile
                , readDocBook
+               , readOPML
                , readNative
                -- * Writers: converting /from/ Pandoc format
                , Writer (..)
@@ -113,6 +114,7 @@ import Text.Pandoc.Readers.Markdown
 import Text.Pandoc.Readers.MediaWiki
 import Text.Pandoc.Readers.RST
 import Text.Pandoc.Readers.DocBook
+import Text.Pandoc.Readers.OPML
 import Text.Pandoc.Readers.LaTeX
 import Text.Pandoc.Readers.HTML
 import Text.Pandoc.Readers.Textile
@@ -192,6 +194,7 @@ readers = [("native"       , \_ s -> return $ readNative s)
           ,("rst"          , \o s -> return $ readRST o s)
           ,("mediawiki"    , \o s -> return $ readMediaWiki o s)
           ,("docbook"      , \o s -> return $ readDocBook o s)
+          ,("opml"         , \o s -> return $ readOPML o s)
           ,("textile"      , \o s -> return $ readTextile o s) -- TODO : textile+lhs
           ,("html"         , \o s -> return $ readHtml o s)
           ,("latex"        , \o s -> return $ readLaTeX o s)
diff --git a/src/Text/Pandoc/Readers/OPML.hs b/src/Text/Pandoc/Readers/OPML.hs
new file mode 100644
index 000000000..53b599349
--- /dev/null
+++ b/src/Text/Pandoc/Readers/OPML.hs
@@ -0,0 +1,95 @@
+module Text.Pandoc.Readers.OPML ( readOPML ) where
+import Data.Char (toUpper)
+import Text.Pandoc.Options
+import Text.Pandoc.Definition
+import Text.Pandoc.Builder
+import Text.Pandoc.Readers.HTML (readHtml)
+import Text.Pandoc.Readers.Markdown (readMarkdown)
+import Text.XML.Light
+import Text.HTML.TagSoup.Entity (lookupEntity)
+import Data.Generics
+import Data.Monoid
+import Control.Monad.State
+import Control.Applicative ((<$>), (<$))
+
+type OPML = State OPMLState
+
+data OPMLState = OPMLState{
+                        opmlSectionLevel :: Int
+                      , opmlDocTitle     :: Inlines
+                      , opmlDocAuthors   :: [Inlines]
+                      , opmlDocDate      :: Inlines
+                      } deriving Show
+
+readOPML :: ReaderOptions -> String -> Pandoc
+readOPML _ inp  = setTitle (opmlDocTitle st')
+                   $ setAuthors (opmlDocAuthors st')
+                   $ setDate (opmlDocDate st')
+                   $ doc $ mconcat bs
+  where (bs, st') = runState (mapM parseBlock $ normalizeTree $ parseXML inp)
+                             OPMLState{ opmlSectionLevel = 0
+                                    , opmlDocTitle = mempty
+                                    , opmlDocAuthors = []
+                                    , opmlDocDate = mempty
+                                    }
+
+-- normalize input, consolidating adjacent Text and CRef elements
+normalizeTree :: [Content] -> [Content]
+normalizeTree = everywhere (mkT go)
+  where go :: [Content] -> [Content]
+        go (Text (CData CDataRaw _ _):xs) = xs
+        go (Text (CData CDataText s1 z):Text (CData CDataText s2 _):xs) =
+           Text (CData CDataText (s1 ++ s2) z):xs
+        go (Text (CData CDataText s1 z):CRef r:xs) =
+           Text (CData CDataText (s1 ++ convertEntity r) z):xs
+        go (CRef r:Text (CData CDataText s1 z):xs) =
+             Text (CData CDataText (convertEntity r ++ s1) z):xs
+        go (CRef r1:CRef r2:xs) =
+             Text (CData CDataText (convertEntity r1 ++ convertEntity r2) Nothing):xs
+        go xs = xs
+
+convertEntity :: String -> String
+convertEntity e = maybe (map toUpper e) (:[]) (lookupEntity e)
+
+-- convenience function to get an attribute value, defaulting to ""
+attrValue :: String -> Element -> String
+attrValue attr elt =
+  case lookupAttrBy (\x -> qName x == attr) (elAttribs elt) of
+    Just z  -> z
+    Nothing -> ""
+
+asHtml :: String -> Inlines
+asHtml s = case readHtml def s of
+                Pandoc _ [Plain ils] -> fromList ils
+                _ -> mempty
+
+asMarkdown :: String -> Blocks
+asMarkdown s = fromList bs
+  where Pandoc _ bs = readMarkdown def s
+
+getBlocks :: Element -> OPML Blocks
+getBlocks e =  mconcat <$> (mapM parseBlock $ elContent e)
+
+parseBlock :: Content -> OPML Blocks
+parseBlock (Elem e) =
+  case qName (elName e) of
+        "ownerName"    -> mempty <$ modify (\st ->
+                              st{opmlDocAuthors = [text $ strContent e]})
+        "dateModified" -> mempty <$ modify (\st ->
+                              st{opmlDocDate = text $ strContent e})
+        "title"        -> mempty <$ modify (\st ->
+                              st{opmlDocTitle = text $ strContent e})
+        "outline" -> gets opmlSectionLevel >>= sect . (+1)
+        "?xml"  -> return mempty
+        _       -> getBlocks e
+   where sect n = do let headerText = asHtml $ attrValue "text" e
+                     let noteBlocks = asMarkdown $ attrValue "_note" e
+                     modify $ \st -> st{ opmlSectionLevel = n }
+                     bs <- getBlocks e
+                     modify $ \st -> st{ opmlSectionLevel = n - 1 }
+                     let headerText' = case attrValue "type" e of
+                                             "link"  -> link
+                                               (attrValue "url" e) "" headerText
+                                             _ -> headerText
+                     return $ header n headerText' <> noteBlocks <> bs
+parseBlock _ = return mempty
diff --git a/tests/Tests/Old.hs b/tests/Tests/Old.hs
index 9e7493504..c22fa9830 100644
--- a/tests/Tests/Old.hs
+++ b/tests/Tests/Old.hs
@@ -124,6 +124,10 @@ tests = [ testGroup "markdown"
           , test "reader" ["-r", "mediawiki", "-w", "native", "-s"]
             "mediawiki-reader.wiki" "mediawiki-reader.native"
           ]
+        , testGroup "opml"
+          [ test "reader" ["-r", "opml", "-w", "native", "-s"]
+            "opml-reader.opml" "opml-reader.native"
+          ]
         , testGroup "other writers" $ map (\f -> testGroup f $ writerTests f)
           [ "opendocument" , "context" , "texinfo"
           , "man" , "plain" , "rtf", "org", "asciidoc"
diff --git a/tests/opml-reader.native b/tests/opml-reader.native
new file mode 100644
index 000000000..8a627c025
--- /dev/null
+++ b/tests/opml-reader.native
@@ -0,0 +1,66 @@
+Pandoc (Meta {docTitle = [Str "states.opml"], docAuthors = [[Str "Dave",Space,Str "Winer"]], docDate = [Str "Thu,",Space,Str "14",Space,Str "Jul",Space,Str "2005",Space,Str "23:41:05",Space,Str "GMT"]})
+[Header 1 ("",[],[]) [Str "United",Space,Str "States"]
+,Header 2 ("",[],[]) [Str "Far",Space,Str "West"]
+,Header 3 ("",[],[]) [Str "Alaska"]
+,Header 3 ("",[],[]) [Str "California"]
+,Header 3 ("",[],[]) [Str "Hawaii"]
+,Header 3 ("",[],[]) [Strong [Str "Nevada"]]
+,Para [Str "I",Space,Str "lived",Space,Str "here",Space,Emph [Str "once"],Str "."]
+,Para [Str "Loved",Space,Str "it."]
+,Header 4 ("",[],[]) [Link [Str "Reno"] ("http://www.reno.gov","")]
+,Header 4 ("",[],[]) [Str "Las",Space,Str "Vegas"]
+,Header 4 ("",[],[]) [Str "Ely"]
+,Header 4 ("",[],[]) [Str "Gerlach"]
+,Header 3 ("",[],[]) [Str "Oregon"]
+,Header 3 ("",[],[]) [Str "Washington"]
+,Header 2 ("",[],[]) [Str "Great",Space,Str "Plains"]
+,Header 3 ("",[],[]) [Str "Kansas"]
+,Header 3 ("",[],[]) [Str "Nebraska"]
+,Header 3 ("",[],[]) [Str "North",Space,Str "Dakota"]
+,Header 3 ("",[],[]) [Str "Oklahoma"]
+,Header 3 ("",[],[]) [Str "South",Space,Str "Dakota"]
+,Header 2 ("",[],[]) [Str "Mid",Str "-",Str "Atlantic"]
+,Header 3 ("",[],[]) [Str "Delaware"]
+,Header 3 ("",[],[]) [Str "Maryland"]
+,Header 3 ("",[],[]) [Str "New",Space,Str "Jersey"]
+,Header 3 ("",[],[]) [Str "New",Space,Str "York"]
+,Header 3 ("",[],[]) [Str "Pennsylvania"]
+,Header 2 ("",[],[]) [Str "Midwest"]
+,Header 3 ("",[],[]) [Str "Illinois"]
+,Header 3 ("",[],[]) [Str "Indiana"]
+,Header 3 ("",[],[]) [Str "Iowa"]
+,Header 3 ("",[],[]) [Str "Kentucky"]
+,Header 3 ("",[],[]) [Str "Michigan"]
+,Header 3 ("",[],[]) [Str "Minnesota"]
+,Header 3 ("",[],[]) [Str "Missouri"]
+,Header 3 ("",[],[]) [Str "Ohio"]
+,Header 3 ("",[],[]) [Str "West",Space,Str "Virginia"]
+,Header 3 ("",[],[]) [Str "Wisconsin"]
+,Header 2 ("",[],[]) [Str "Mountains"]
+,Header 3 ("",[],[]) [Str "Colorado"]
+,Header 3 ("",[],[]) [Str "Idaho"]
+,Header 3 ("",[],[]) [Str "Montana"]
+,Header 3 ("",[],[]) [Str "Utah"]
+,Header 3 ("",[],[]) [Str "Wyoming"]
+,Header 2 ("",[],[]) [Str "New",Space,Str "England"]
+,Header 3 ("",[],[]) [Str "Connecticut"]
+,Header 3 ("",[],[]) [Str "Maine"]
+,Header 3 ("",[],[]) [Str "Massachusetts"]
+,Header 3 ("",[],[]) [Str "New",Space,Str "Hampshire"]
+,Header 3 ("",[],[]) [Str "Rhode",Space,Str "Island"]
+,Header 3 ("",[],[]) [Str "Vermont"]
+,Header 2 ("",[],[]) [Str "South"]
+,Header 3 ("",[],[]) [Str "Alabama"]
+,Header 3 ("",[],[]) [Str "Arkansas"]
+,Header 3 ("",[],[]) [Str "Florida"]
+,Header 3 ("",[],[]) [Str "Georgia"]
+,Header 3 ("",[],[]) [Str "Louisiana"]
+,Header 3 ("",[],[]) [Str "Mississippi"]
+,Header 3 ("",[],[]) [Str "North",Space,Str "Carolina"]
+,Header 3 ("",[],[]) [Str "South",Space,Str "Carolina"]
+,Header 3 ("",[],[]) [Str "Tennessee"]
+,Header 3 ("",[],[]) [Str "Virginia"]
+,Header 2 ("",[],[]) [Str "Southwest"]
+,Header 3 ("",[],[]) [Str "Arizona"]
+,Header 3 ("",[],[]) [Str "New",Space,Str "Mexico"]
+,Header 3 ("",[],[]) [Str "Texas"]]
diff --git a/tests/opml-reader.opml b/tests/opml-reader.opml
new file mode 100644
index 000000000..54dd592ea
--- /dev/null
+++ b/tests/opml-reader.opml
@@ -0,0 +1,91 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<opml version="2.0">
+	<head>
+		<title>states.opml</title>
+		<dateCreated>Tue, 15 Mar 2005 16:35:45 GMT</dateCreated>
+		<dateModified>Thu, 14 Jul 2005 23:41:05 GMT</dateModified>
+		<ownerName>Dave Winer</ownerName>
+		<ownerEmail>dave@scripting.com</ownerEmail>
+		<expansionState>1, 6, 13, 16, 18, 20</expansionState>
+		<vertScrollState>1</vertScrollState>
+		<windowTop>106</windowTop>
+		<windowLeft>106</windowLeft>
+		<windowBottom>558</windowBottom>
+		<windowRight>479</windowRight>
+		</head>
+	<body>
+		<outline text="United States">
+			<outline text="Far West">
+				<outline text="Alaska"/>
+				<outline text="California"/>
+				<outline text="Hawaii"/>
+                                <outline text="&lt;strong&gt;Nevada&lt;/strong&gt;" _note="I lived here *once*.&#10;&#10;Loved it.">
+                                  <outline text="Reno" created="Tue, 12 Jul 2005 23:56:35 GMT" type="link" url="http://www.reno.gov"/>
+					<outline text="Las Vegas" created="Tue, 12 Jul 2005 23:56:37 GMT"/>
+					<outline text="Ely" created="Tue, 12 Jul 2005 23:56:39 GMT"/>
+					<outline text="Gerlach" created="Tue, 12 Jul 2005 23:56:47 GMT"/>
+					</outline>
+				<outline text="Oregon"/>
+				<outline text="Washington"/>
+				</outline>
+			<outline text="Great Plains">
+				<outline text="Kansas"/>
+				<outline text="Nebraska"/>
+				<outline text="North Dakota"/>
+				<outline text="Oklahoma"/>
+				<outline text="South Dakota"/>
+				</outline>
+			<outline text="Mid-Atlantic">
+				<outline text="Delaware"/>
+				<outline text="Maryland"/>
+				<outline text="New Jersey"/>
+				<outline text="New York"/>
+				<outline text="Pennsylvania"/>
+				</outline>
+			<outline text="Midwest">
+				<outline text="Illinois"/>
+				<outline text="Indiana"/>
+				<outline text="Iowa"/>
+				<outline text="Kentucky"/>
+				<outline text="Michigan"/>
+				<outline text="Minnesota"/>
+				<outline text="Missouri"/>
+				<outline text="Ohio"/>
+				<outline text="West Virginia"/>
+				<outline text="Wisconsin"/>
+				</outline>
+			<outline text="Mountains">
+				<outline text="Colorado"/>
+				<outline text="Idaho"/>
+				<outline text="Montana"/>
+				<outline text="Utah"/>
+				<outline text="Wyoming"/>
+				</outline>
+			<outline text="New England">
+				<outline text="Connecticut"/>
+				<outline text="Maine"/>
+				<outline text="Massachusetts"/>
+				<outline text="New Hampshire"/>
+				<outline text="Rhode Island"/>
+				<outline text="Vermont"/>
+				</outline>
+			<outline text="South">
+				<outline text="Alabama"/>
+				<outline text="Arkansas"/>
+				<outline text="Florida"/>
+				<outline text="Georgia"/>
+				<outline text="Louisiana"/>
+				<outline text="Mississippi"/>
+				<outline text="North Carolina"/>
+				<outline text="South Carolina"/>
+				<outline text="Tennessee"/>
+				<outline text="Virginia"/>
+				</outline>
+			<outline text="Southwest">
+				<outline text="Arizona"/>
+				<outline text="New Mexico"/>
+				<outline text="Texas"/>
+				</outline>
+			</outline>
+		</body>
+	</opml>