-- feed.
--
module TSN.Picklers (
- xp_date )
+ xp_date,
+ xp_gamedate,
+ xp_time )
where
+-- System imports.
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.
--
from_date :: UTCTime -> String
from_date = formatTime defaultTimeLocale format
+
+
+-- | (Un)pickle a UTCTime from a weather forecast's gamedate. Example
+-- input looks like,
+--
+-- \<forecast gamedate=\"Monday, December 30th\"\>
+--
+-- When unpickling we get rid of the suffixes \"st\", \"nd\", \"rd\", and
+-- \"th\". During pickling, we add them back based on the last digit
+-- of the date.
+--
+xp_gamedate :: PU UTCTime
+xp_gamedate =
+ (to_gamedate, from_gamedate) `xpWrapMaybe` xpText
+ where
+ format = "%A, %B %-d"
+
+ to_gamedate :: String -> Maybe UTCTime
+ to_gamedate s =
+ parseTime defaultTimeLocale format s'
+ where
+ s' = case (reverse s) of
+ (c2:c1:cs) -> let suffix = [c1,c2]
+ in
+ case suffix of
+ "st" -> reverse cs
+ "nd" -> reverse cs
+ "rd" -> reverse cs
+ "th" -> reverse cs
+ _ -> s -- Unknown suffix, leave it alone.
+ _ -> s -- The String is less than two characters long,
+ -- leave it alone.
+
+
+ from_gamedate :: UTCTime -> String
+ from_gamedate d = s ++ (suffix s)
+ where
+ s = formatTime defaultTimeLocale format d
+
+ suffix :: String -> String
+ suffix cs =
+ case (reverse cs) of
+ [] -> []
+ ('1':_) -> "st"
+ ('2':_) -> "nd"
+ ('3':_) -> "rd"
+ _ -> "th"
+
+
+-- | (Un)pickle a UTCTime without the date portion.
+--
+xp_time :: PU UTCTime
+xp_time =
+ (to_time, from_time) `xpWrapMaybe` xpText
+ where
+ format = "%I:%M %p"
+
+ to_time :: String -> Maybe UTCTime
+ to_time = parseTime defaultTimeLocale format
+
+ from_time :: UTCTime -> String
+ from_time = formatTime defaultTimeLocale format
+