-- | (Un)picklers for data types present in The Sports Network XML
--   feed.
--
module TSN.Picklers (
  xp_date )
where

import Data.Time.Clock ( UTCTime )
import Data.Time.Format ( formatTime, parseTime )
import System.Locale ( defaultTimeLocale )
import Text.Read ( readMaybe )
import Text.XML.HXT.Arrow.Pickle (
  XmlPickler(..),
  xpText,
  xpWrapMaybe )
import Text.XML.HXT.Arrow.Pickle.Xml ( PU )

instance XmlPickler Bool where
  xpickle =
    (to_bool, from_bool) `xpWrapMaybe` xpText
    where
      to_bool :: String -> Maybe Bool
      to_bool = readMaybe

      from_bool :: Bool -> String
      from_bool = show


-- | (Un)pickle a UTCTime without the time portion.
--
xp_date :: PU UTCTime
xp_date =
  (to_date, from_date) `xpWrapMaybe` xpText
  where
    format = "%-m/%-d/%Y"

    to_date :: String -> Maybe UTCTime
    to_date = parseTime defaultTimeLocale format

    from_date :: UTCTime -> String
    from_date = formatTime defaultTimeLocale format