now I just need to fix shake rules so things are needed/provided correctly

app/Main.hs

@@ -8,25 +8,16 @@
 
 module Main where
 
-import Control.Monad (forM, void)
-import Data.Aeson.Types (Result (..))
-import Data.List (nub, sortOn)
 import Data.Text (Text)
 import Data.Time (UTCTime, defaultTimeLocale, formatTime, parseTimeM)
 import Deriving.Aeson
 import Deriving.Aeson.Stock (PrefixedSnake)
-import Development.Shake (Action, Rules, (%>), (|%>), (~>))
-import Development.Shake.FilePath ((<.>), (</>))
-import Text.Pandoc (Block (Plain), Meta (..), MetaValue (..), Pandoc (..))
-import qualified Data.Aeson.Types as A
+import Development.Shake (Action, Rules, (|%>), (~>))
+import Development.Shake.FilePath ((</>))
 import qualified Data.HashMap.Strict as HM
-import qualified Data.Ord as Ord
 import qualified Data.Text as T
 import qualified Development.Shake as Shake
 import qualified Development.Shake.FilePath as Shake
-import qualified Text.Mustache as Mus
-import qualified Text.Mustache.Compile as Mus
-import qualified Text.Pandoc as Pandoc
 import Config
 import Utilities
 import Templates

app/Templates.hs

@@ -12,7 +12,7 @@ import qualified Data.Aeson as A
 import qualified Data.Text as T
 import Development.Shake.FilePath ((</>))
 
-applyTemplate :: ToJSON a => String -> a ->  Text
+applyTemplate :: ToJSON a => String -> a -> Action Text
 applyTemplate templateName context = do
   tmpl <- readTemplate $ "templates" </> templateName
   case Mus.checkedSubstitute tmpl (A.toJSON context) of

app/Utilities.hs

@@ -9,6 +9,8 @@ import qualified Development.Shake.FilePath as Shake
 import qualified Text.Pandoc as Pandoc
 import Config
 import Development.Shake (Action)
+import Text.Pandoc 
+import Data.Aeson as A
 
 indexHtmlOutputPath :: FilePath -> FilePath
 indexHtmlOutputPath srcPath =
@@ -21,19 +23,34 @@ indexHtmlSourcePath =
     . Shake.dropTrailingPathSeparator
     . Shake.dropFileName
 
-typstToHtml :: FilePath -> Action Text
+typstToHtml :: FromJSON a => FilePath -> Action (a, Text)
 typstToHtml filePath = do
   content <- Shake.readFile' filePath
   Shake.quietly . Shake.traced "Typst to HTML" $ do
-    doc <- runPandoc . Pandoc.readTypst readerOptions . T.pack $ content
-    
-    runPandoc . Pandoc.writeHtml5String writerOptions $ doc
+    doc@(Pandoc meta _) <- runPandoc . Pandoc.readTypst readerOptions . T.pack $ content
+    meta' <- fromMeta meta
+    html <- runPandoc . Pandoc.writeHtml5String writerOptions $ doc
+    return (meta', html)
   where
     readerOptions =
       Pandoc.def {Pandoc.readerExtensions = Pandoc.pandocExtensions}
     writerOptions =
       Pandoc.def {Pandoc.writerExtensions = Pandoc.pandocExtensions}
-
-runPandoc action =
-      Pandoc.runIO (Pandoc.setVerbosity Pandoc.ERROR >> action)
-        >>= either (fail . show) return
+    fromMeta (Meta meta) =
+          A.fromJSON . A.toJSON <$> traverse metaValueToJSON meta >>= \case
+            Success res -> pure res
+            Error err -> fail $ "json conversion error:" <> err
+    metaValueToJSON = \case
+          MetaMap m -> A.toJSON <$> traverse metaValueToJSON m
+          MetaList m -> A.toJSONList <$> traverse metaValueToJSON m
+          MetaBool m -> pure $ A.toJSON m
+          MetaString m -> pure $ A.toJSON $ T.strip m
+          MetaInlines m -> metaValueToJSON $ MetaBlocks [Plain m]
+          MetaBlocks m ->
+            fmap (A.toJSON . T.strip)
+              . runPandoc
+              . Pandoc.writePlain Pandoc.def
+              $ Pandoc mempty m
+    runPandoc action =
+          Pandoc.runIO (Pandoc.setVerbosity Pandoc.ERROR >> action)
+            >>= either (fail . show) return