#!/usr/bin/env runhaskell
-- filter.hs
import Text.Pandoc.JSON
    ( Block(CodeBlock), ToJSONFilter(toJSONFilter) )
import qualified Data.Text.IO as TIO
import qualified Data.Text as T

doInclude :: Block -> IO Block
doInclude cb@(CodeBlock (id, classes, namevals) contents) =
  case lookup (T.pack "include") namevals of
       Just f     -> CodeBlock (id, classes, namevals) <$>
                      TIO.readFile (T.unpack f)
       Nothing    -> return cb
doInclude x = return x

main :: IO ()
main = toJSONFilter doInclude