Allow to wrap embedded video in a div

Set environment variable VIDEO_WRAPPER_CSS_CLASS="your-css-class" and
the iframe will be embeded in a div with the provided class.

src/Lib.hs

@@ -17,16 +17,17 @@ import Text.Pandoc.Walk (query)
 import Data.Maybe (fromMaybe, mapMaybe)
 import System.Environment (lookupEnv)
 import Control.Applicative ((<|>))
+import WrapperElement (WrapperElement(..), wrapWithElement, wrapperElementFromMaybeString)
 
 extractDimensions :: [Inline] -> Maybe Dimensions
 extractDimensions = fmap fst <$> uncons . mapMaybe (parseDimensions . query (\(Str s) -> s))
 
-inlineHtmlVideo :: Maybe Dimensions -> Inline -> Maybe Inline
-inlineHtmlVideo defaultDimensions (Image _ inlines (url, _)) =
-  rawHtml . renderVideoEmbed . (`Video` dimensions) <$> parseVideoId url
+inlineHtmlVideo :: Maybe Dimensions -> WrapperElement -> Inline -> Maybe Inline
+inlineHtmlVideo defaultDimensions wrapperEl (Image _ inlines (url, _)) =
+  rawHtml . wrapWithElement wrapperEl . renderVideoEmbed . (`Video` dimensions) <$> parseVideoId url
   where rawHtml = RawInline (Format "html") . LT.unpack
         dimensions = extractDimensions inlines <|> defaultDimensions
-inlineHtmlVideo _ _ = Nothing
+inlineHtmlVideo _ _ _ = Nothing
 
 onFormat :: Format -> (a -> Maybe a) -> Maybe Format -> a -> a
 onFormat format f maybeFormat x
@@ -36,4 +37,5 @@ onFormat format f maybeFormat x
 process :: IO ()
 process = do
   defaultDimensions <- lookupEnv "VIDEO_DIMENSIONS"
-  toJSONFilter $ onFormat (Format "html") (inlineHtmlVideo (defaultDimensions >>= parseDimensions))
+  wrapperElementStr <- lookupEnv "VIDEO_WRAPPER_CSS_CLASS"
+  toJSONFilter $ onFormat (Format "html") (inlineHtmlVideo (defaultDimensions >>= parseDimensions) (wrapperElementFromMaybeString wrapperElementStr))

src/WrapperElement.hs

@@ -0,0 +1,16 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module WrapperElement where
+
+import qualified Data.Text.Lazy as LT
+
+data WrapperElement = DivWithClass String | NoWrapper
+
+wrapperElementFromMaybeString :: Maybe String -> WrapperElement
+wrapperElementFromMaybeString Nothing = NoWrapper
+wrapperElementFromMaybeString (Just str) = DivWithClass str
+
+wrapWithElement :: WrapperElement -> LT.Text -> LT.Text
+wrapWithElement NoWrapper innerText = innerText
+wrapWithElement (DivWithClass cssClass) innerText =
+  "<div class=\"" <> (LT.pack cssClass) <> "\">" <> innerText <> "</div>"

test/Spec.hs

@@ -1,24 +1,32 @@
 import Test.Hspec
 import Text.Pandoc.Definition (Format(..), Inline(..), Attr(), nullAttr)
+import WrapperElement (WrapperElement(..))
 import Lib (inlineHtmlVideo)
 
 main :: IO ()
 main = hspec $ do
   describe "inlneHTMLVideo" $ do
     it "returns Nothing for non-image tag" $ do
-      inlineHtmlVideo Nothing (Str "hello") `shouldBe` (Nothing)
+      inlineHtmlVideo Nothing NoWrapper (Str "hello") `shouldBe` (Nothing)
     it "returns Vimeo iframe for correctly formatted image tag" $ do
-      inlineHtmlVideo Nothing (Image nullAttr [] ("vimeo:123", ""))
+      inlineHtmlVideo Nothing NoWrapper (Image nullAttr [] ("vimeo:123", ""))
         `shouldBe` (Just $
                      RawInline (Format "html")
                      "<iframe allowfullscreen mozallowfullscreen frameborder=\"0\" src=\"https://player.vimeo.com/video/123?title=0&amp;amp;portrait=0&amp;amp;badge=0\" webkitallowfullscreen></iframe>")
     it "uses provided default dimensions" $ do
-      inlineHtmlVideo (Just (10, 20)) (Image nullAttr [] ("vimeo:123", ""))
+      inlineHtmlVideo (Just (10, 20)) NoWrapper (Image nullAttr [] ("vimeo:123", ""))
         `shouldBe` (Just $
                      RawInline (Format "html")
                      "<iframe height=\"20\" width=\"10\" allowfullscreen mozallowfullscreen frameborder=\"0\" src=\"https://player.vimeo.com/video/123?title=0&amp;amp;portrait=0&amp;amp;badge=0\" webkitallowfullscreen></iframe>")
     it "overrides default dimensions" $ do
-      inlineHtmlVideo Nothing (Image nullAttr [(Str "40x50")] ("vimeo:123", ""))
+      inlineHtmlVideo Nothing NoWrapper (Image nullAttr [(Str "40x50")] ("vimeo:123", ""))
         `shouldBe` (Just $
                      RawInline (Format "html")
                      "<iframe height=\"50\" width=\"40\" allowfullscreen mozallowfullscreen frameborder=\"0\" src=\"https://player.vimeo.com/video/123?title=0&amp;amp;portrait=0&amp;amp;badge=0\" webkitallowfullscreen></iframe>")
+    it "wraps it in a div" $ do
+      inlineHtmlVideo Nothing (DivWithClass "class1 class2") (Image nullAttr [] ("vimeo:123", ""))
+        `shouldBe` (Just $
+                     RawInline (Format "html")
+                     "<div class=\"class1 class2\"><iframe allowfullscreen mozallowfullscreen frameborder=\"0\" src=\"https://player.vimeo.com/video/123?title=0&amp;amp;portrait=0&amp;amp;badge=0\" webkitallowfullscreen></iframe></div>")
+    it "doesn't wrap when no video" $ do
+      inlineHtmlVideo Nothing (DivWithClass "testclass") (Str "hello") `shouldBe` (Nothing)

videofilter.cabal

@@ -19,6 +19,7 @@ library
                      , VideoParser
                      , Definitions
                      , VideoRenderer
+                     , WrapperElement
   build-depends:       base >= 4.7 && < 5
                      , lucid
                      , pandoc