module Util.Meta where
import Text.Pandoc (readMarkdown,def)
import Text.Pandoc.Shared (stringify)
import Text.Pandoc.Definition
import Data.Maybe (fromMaybe)
import Util.Util (lookupDefault)
getMetaBool :: String -> Meta -> Meta -> Bool
getMetaBool name meta defaults = fromMaybe False $ lookupDefault name meta defaults >>= toBool
getMetaInlines :: String -> Meta -> Meta -> [Inline]
getMetaInlines name meta defaults = fromMaybe [] $ lookupDefault name meta defaults >>= toInlines
getMetaBlock :: String -> Meta -> Meta -> [Block]
getMetaBlock name meta defaults = fromMaybe [] $ lookupDefault name meta defaults >>= toBlocks
getMetaString :: String -> Meta -> Meta -> String
getMetaString name meta defaults = fromMaybe [] $ lookupDefault name meta defaults >>= toString
toInlines :: MetaValue -> Maybe [Inline]
toInlines (MetaString s) = return $ getInlines $ readMarkdown def s
where getInlines (Pandoc _ bs) = concatMap getInline bs
getInline (Plain ils) = ils
getInline (Para ils) = ils
getInline _ = []
toInlines (MetaInlines s) = return s
toInlines _ = Nothing
toBool :: MetaValue -> Maybe Bool
toBool (MetaBool b) = return b
toBool _ = Nothing
toBlocks :: MetaValue -> Maybe [Block]
toBlocks (MetaBlocks bs) = return bs
toBlocks (MetaInlines ils) = return [Plain ils]
toBlocks (MetaString s) = return $ getBlocks $ readMarkdown def s
where getBlocks (Pandoc _ bs) = bs
toBlocks _ = Nothing
toString :: MetaValue -> Maybe String
toString (MetaString s) = Just s
toString (MetaBlocks b) = Just $ stringify b
toString (MetaInlines i) = Just $ stringify i
toString _ = Nothing