X-Git-Url: http://git.cielonegro.org/gitweb.cgi?a=blobdiff_plain;f=Network%2FHTTP%2FLucu%2FRFC1123DateTime.hs;h=bc2c5901233bd8679955e7aff0e4c3a38cc7b009;hb=9ac730212cb361eb10e5fe4ad0eec6758e2b200a;hp=9c58e51db91048c196c6a8d54a03c1c9bf272d67;hpb=3c7a58ab749a55a30466a033b170536bcdf18b98;p=Lucu.git

diff --git a/Network/HTTP/Lucu/RFC1123DateTime.hs b/Network/HTTP/Lucu/RFC1123DateTime.hs
index 9c58e51..bc2c590 100644
--- a/Network/HTTP/Lucu/RFC1123DateTime.hs
+++ b/Network/HTTP/Lucu/RFC1123DateTime.hs
@@ -1,75 +1,109 @@
+-- |This module parses and prints RFC 1123 Date and Time string.
+-- 
+-- In general you don't have to use this module directly.
 module Network.HTTP.Lucu.RFC1123DateTime
-    ( formatRFC1123DateTime -- CalendarTime -> String
-    , formatHTTPDateTime    -- ClockTime -> String
-    , parseHTTPDateTime     -- String -> Maybe ClockTime
+    ( formatRFC1123DateTime
+    , formatHTTPDateTime
+    , parseHTTPDateTime
     )
     where
 
-import Control.Monad
-import System.Time
-import System.Locale
-import Text.ParserCombinators.Parsec
-import Text.Printf
+import           Control.Monad
+import           Data.Time
+import           Data.Time.Calendar.WeekDate
+import qualified Data.ByteString.Lazy as Lazy (ByteString)
+import           Network.HTTP.Lucu.Format
+import           Network.HTTP.Lucu.Parser
+import           Prelude hiding (min)
 
-month = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
-week  = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"]
 
-formatRFC1123DateTime :: CalendarTime -> String
-formatRFC1123DateTime time
-    = printf "%s, %02d %s %04d %02d:%02d:%02d %s"
-      (week     !! fromEnum (ctWDay  time))
-      (ctDay    time)
-      (month    !! fromEnum (ctMonth time))
-      (ctYear   time)
-      (ctHour   time)
-      (ctMin    time)
-      (ctSec    time)
-      (ctTZName time)
+monthStr :: [String]
+monthStr =  ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
 
+weekStr :: [String]
+weekStr =  ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"]
 
-formatHTTPDateTime :: ClockTime -> String
-formatHTTPDateTime = formatRFC1123DateTime . (\cal -> cal { ctTZName = "GMT" }) . toUTCTime
+-- |Format a 'System.Time.CalendarTime' to RFC 1123 Date and Time
+-- string.
+formatRFC1123DateTime :: ZonedTime -> String
+formatRFC1123DateTime zonedTime
+    = let localTime          = zonedTimeToLocalTime zonedTime
+          timeZone           = zonedTimeZone zonedTime
+          (year, month, day) = toGregorian (localDay localTime)
+          (_, _, week)       = toWeekDate (localDay localTime)
+          timeOfDay          = localTimeOfDay localTime
+      in
+        id       (weekStr !! (week - 1))
+        ++ ", " ++
+        fmtDec 2 day
+        ++ " "  ++
+        id       (monthStr !! (month - 1))
+        ++ " " ++
+        fmtDec 4 (fromInteger year)
+        ++ " " ++
+        fmtDec 2 (todHour timeOfDay)
+        ++ ":" ++
+        fmtDec 2 (todMin timeOfDay)
+        ++ ":" ++
+        fmtDec 2 (floor (todSec timeOfDay))
+        ++ " " ++
+        id       (timeZoneName timeZone)
+      
 
+-- |Format a 'System.Time.ClockTime' to HTTP Date and Time. Time zone
+-- will be always UTC but prints as GMT.
+formatHTTPDateTime :: UTCTime -> String
+formatHTTPDateTime utcTime
+    = let timeZone  = TimeZone 0 False "GMT"
+          zonedTime = utcToZonedTime timeZone utcTime
+      in
+        formatRFC1123DateTime zonedTime
 
-parseHTTPDateTime :: String -> Maybe ClockTime
+
+-- |Parse an HTTP Date and Time.
+--
+-- Limitation: RFC 2616 (HTTP\/1.1) says we must accept these three
+-- formats:
+--
+-- * @Sun, 06 Nov 1994 08:49:37 GMT  ; RFC 822, updated by RFC 1123@
+--
+-- * @Sunday, 06-Nov-94 08:49:37 GMT ; RFC 850, obsoleted by RFC 1036@
+--
+-- * @Sun Nov  6 08:49:37 1994       ; ANSI C's asctime() format@
+--
+-- ...but currently this function only supports the RFC 1123
+-- format. This is a violation of RFC 2616 so this should be fixed
+-- later. What a bother!
+parseHTTPDateTime :: Lazy.ByteString -> Maybe UTCTime
 parseHTTPDateTime src
-    = case parse httpDateTime "" src of
-        Right ct  -> Just ct
-        Left  err -> Nothing
+    = case parse httpDateTime src of
+        (# Success ct, _ #) -> Just ct
+        (# _         , _ #) -> Nothing
+
 
-httpDateTime :: Parser ClockTime
-httpDateTime = do foldl (<|>) (unexpected "") (map (try . string) week)
-                  char ','
-                  char ' '
+httpDateTime :: Parser UTCTime
+httpDateTime = do _    <- foldl (<|>) failP (map string weekStr)
+                  _    <- char ','
+                  _    <- char ' '
                   day  <- liftM read (count 2 digit)
-                  char ' '
-                  mon  <- foldl (<|>) (unexpected "") (map tryEqToFst (zip month [1..]))
-                  char ' '
+                  _    <- char ' '
+                  mon  <- foldl (<|>) failP (map tryEqToFst (zip monthStr [1..]))
+                  _    <- char ' '
                   year <- liftM read (count 4 digit)
-                  char ' '
+                  _    <- char ' '
                   hour <- liftM read (count 2 digit)
-                  char ':'
+                  _    <- char ':'
                   min  <- liftM read (count 2 digit)
-                  char ':'
-                  sec  <- liftM read (count 2 digit)
-                  char ' '
-                  string "GMT"
+                  _    <- char ':'
+                  sec  <- liftM read (count 2 digit) :: Parser Int
+                  _    <- char ' '
+                  _    <- string "GMT"
                   eof
-                  return $ toClockTime $ CalendarTime {
-                               ctYear    = year
-                             , ctMonth   = toEnum (mon - 1)
-                             , ctDay     = day
-                             , ctHour    = hour
-                             , ctMin     = min
-                             , ctSec     = sec
-                             , ctPicosec = 0
-                             , ctTZ      = 0
-                             , ctWDay    = undefined
-                             , ctYDay    = undefined
-                             , ctTZName  = undefined
-                             , ctIsDST   = undefined
-                             }
+                  let julianDay = fromGregorian year mon day
+                      timeOfDay = TimeOfDay hour min (fromIntegral sec)
+                      utcTime   = UTCTime julianDay (timeOfDayToTime timeOfDay)
+                  return utcTime
     where
       tryEqToFst :: (String, a) -> Parser a
-      tryEqToFst (str, a) = try $ string str >> return a
+      tryEqToFst (str, a) = string str >> return a
       
\ No newline at end of file