{-# LANGUAGE Safe #-}

-- Note: this file derives from old-locale:System.Locale.hs, which is copyright (c) The University of Glasgow 2001
module Data.Time.Format.Locale
    ( TimeLocale(..)
    , defaultTimeLocale
    , iso8601DateFormat
    , rfc822DateFormat
    ) where

import Data.Time.LocalTime.Internal.TimeZone

data TimeLocale = TimeLocale
    { wDays :: [(String, String)]
        -- ^ full and abbreviated week days, starting with Sunday
    , months :: [(String, String)]
        -- ^ full and abbreviated months
    , amPm :: (String, String)
        -- ^ AM\/PM symbols
    , dateTimeFmt, dateFmt, timeFmt, time12Fmt :: String
        -- ^ formatting strings
    , knownTimeZones :: [TimeZone]
        -- ^ time zones known by name
    } deriving (Eq, Ord, Show)

-- | Locale representing American usage.
--
-- 'knownTimeZones' contains only the ten time-zones mentioned in RFC 802 sec. 5:
-- \"UT\", \"GMT\", \"EST\", \"EDT\", \"CST\", \"CDT\", \"MST\", \"MDT\", \"PST\", \"PDT\".
-- Note that the parsing functions will regardless parse \"UTC\", single-letter military time-zones, and +HHMM format.
defaultTimeLocale :: TimeLocale
defaultTimeLocale =
    TimeLocale
        { wDays =
              [ ("Sunday", "Sun")
              , ("Monday", "Mon")
              , ("Tuesday", "Tue")
              , ("Wednesday", "Wed")
              , ("Thursday", "Thu")
              , ("Friday", "Fri")
              , ("Saturday", "Sat")
              ]
        , months =
              [ ("January", "Jan")
              , ("February", "Feb")
              , ("March", "Mar")
              , ("April", "Apr")
              , ("May", "May")
              , ("June", "Jun")
              , ("July", "Jul")
              , ("August", "Aug")
              , ("September", "Sep")
              , ("October", "Oct")
              , ("November", "Nov")
              , ("December", "Dec")
              ]
        , amPm = ("AM", "PM")
        , dateTimeFmt = "%a %b %e %H:%M:%S %Z %Y"
        , dateFmt = "%m/%d/%y"
        , timeFmt = "%H:%M:%S"
        , time12Fmt = "%I:%M:%S %p"
        , knownTimeZones =
              [ TimeZone 0 False "UT"
              , TimeZone 0 False "GMT"
              , TimeZone (-5 * 60) False "EST"
              , TimeZone (-4 * 60) True "EDT"
              , TimeZone (-6 * 60) False "CST"
              , TimeZone (-5 * 60) True "CDT"
              , TimeZone (-7 * 60) False "MST"
              , TimeZone (-6 * 60) True "MDT"
              , TimeZone (-8 * 60) False "PST"
              , TimeZone (-7 * 60) True "PDT"
              ]
        }

{-# DEPRECATED
iso8601DateFormat "use \"Data.Time.Format.ISO8601\" functions instead"
 #-}

{- | Construct format string according to <http://en.wikipedia.org/wiki/ISO_8601 ISO-8601>.

The @Maybe String@ argument allows to supply an optional time specification. E.g.:

@
'iso8601DateFormat' Nothing            == "%Y-%m-%d"           -- i.e. @/YYYY-MM-DD/@
'iso8601DateFormat' (Just "%H:%M:%S")  == "%Y-%m-%dT%H:%M:%S"  -- i.e. @/YYYY-MM-DD/T/HH:MM:SS/@
@
-}
iso8601DateFormat :: Maybe String -> String
iso8601DateFormat mTimeFmt =
    "%Y-%m-%d" ++
    case mTimeFmt of
        Nothing -> ""
        Just fmt -> 'T' : fmt

-- | Format string according to <http://tools.ietf.org/html/rfc822#section-5 RFC822>.
rfc822DateFormat :: String
rfc822DateFormat = "%a, %_d %b %Y %H:%M:%S %Z"
