module Utils.Print where

import Import.NoModel
import qualified Data.Foldable as Fold
-- hiding (foldr) import Data.Foldable (foldr)

import Control.Monad.Except
import Import hiding (embedFile)
import Data.FileEmbed (embedFile)

import qualified Text.Pandoc          as P
-- import qualified Text.Pandoc.PDF     as P
import qualified Text.Pandoc.Builder  as P

-- import Model.Types.Markup -- TODO-QSV: should this module be moved accordingly?

templateRenewal :: Text
templateRenewal = decodeUtf8 $(Data.FileEmbed.embedFile "templates/letter/fraport_renewal.md")

templateDIN5008 :: Text
templateDIN5008 = decodeUtf8 $(Data.FileEmbed.embedFile "templates/letter/din5008.latex")


-- setMeta :: (HasMeta a, ToMetaValue b) => Text -> b -> a -> a 

-- foldr :: forall b. (Element mono0 -> b -> b) -> b -> mono0 -> b


applyMetas :: (P.HasMeta p, Foldable t, P.ToMetaValue a) => t (Text, a) -> p -> p 
applyMetas metas doc = Fold.foldr (uncurry P.setMeta) doc metas

addMeta :: P.Meta -> P.Pandoc -> P.Pandoc
addMeta m p = meta <> p
  where meta = P.Pandoc m mempty

-- | Apply StoredMarkup as a template to itself and return the resulting Markup
--   This is a hack to allow variable interpolation within a document.
--   Pandoc currently only allows interpolation within templates.
--   An alternative Route would be to use Builders, but this prevents User-edited Markup Templates
reTemplateLetter :: P.PandocMonad m => P.Meta -> StoredMarkup -> m Text
reTemplateLetter meta StoredMarkup{..}  = do
  let strictMarkupInput = toStrict markupInput
      partialPath = "" -- no partials used, see Text.DocTemplates
  mdTemplate <- P.runWithDefaultPartials $ P.compileTemplate partialPath strictMarkupInput
  case mdTemplate of 
    (Left err) -> throwError . P.PandocTemplateError $ pack err 
    (Right templ) -> do
      let readeropts = def { P.readerExtensions = P.pandocExtensions }
          writeropts = def { P.writerTemplate = Just templ }
          -- reader :: (P.PandocMonad m, P.ToSources a)	 => P.ReaderOptions	-> a	-> m P.Pandoc	 
          areader = case markupInputFormat of 
            MarkupHtml      -> P.readHtml
            MarkupMarkdown  -> P.readMarkdown
            MarkupPlaintext -> P.readMarkdown
      doc1 <- areader readeropts strictMarkupInput      
      P.writeMarkdown writeropts $ addMeta meta doc1 -- should we apply metas here?
      

{-

renewalLetter :: (Foldable t, ToMetaValue b, PandocMonad m) => t (Text, b) -> PandocMonad m -> Text 
renewalLetter 

pdfDIN5008 :: MetaPinRenewal -> IO (Either ByteString ByteString)
pdfDIN5008 

-}