IPv6Addr-0.2: Text/IPv6Addr.hs

--------------------------------------------------------------------------------
-- | 
-- Module      :  Text.IPv6Addr
-- Copyright   :  (c) Michel Boucey 2011-2012
-- License     :  BSD-style
-- Maintainer  :  michel.boucey@gmail.com
-- Stability   :  provisional
--
-- Dealing with IPv6 address text representation,
-- canonization and manipulations.
--
--------------------------------------------------------------------------------

module Text.IPv6Addr
    (
      IPv6Addr
    , maybeIPv6Addr
    , maybePureIPv6Addr
    , maybeFullIPv6Addr
    , getIPv6AddrOf
    ) where

import Control.Monad (replicateM)
import Data.Char (intToDigit,isDigit,isHexDigit,toLower)
import Data.Function (on)
import Data.List (group,isSuffixOf,elemIndex,elemIndices,intersperse)
import Data.Maybe (fromJust,isJust)
import qualified Data.Text as T
import Data.Text.Read (decimal)
import Numeric (showIntAtBase)

import Text.IPv6Addr.Internal
import Text.IPv6Addr.Types

-- | Returns Just the text representation of a canonized
-- 'IPv6Addr' in conformation with RFC 5952, or Nothing.
--
-- > maybeIPv6Addr "0:0::FFFF:192.0.2.128" == Just "::ffff:192.0.2.128"
--
maybeIPv6Addr :: T.Text -> Maybe IPv6Addr
maybeIPv6Addr t = maybeTokIPv6Addr t >>= ipv6TokensToText

-- | Returns Just a pure 'IPv6Addr', or Nothing.
--
-- > maybePureIPv6Addr "::ffff:192.0.2.128" == Just "::ffff:c000:280"
--
maybePureIPv6Addr :: T.Text -> Maybe IPv6Addr
maybePureIPv6Addr t = maybeTokPureIPv6Addr t >>= ipv6TokensToText

-- | Returns Just a pure and expanded 'IPv6Addr', or Nothing.
--
-- > maybeFullIPv6Addr "::ffff:192.0.2.128" == Just "0000:0000:0000:0000:0000:ffff:c000:0280"
--
maybeFullIPv6Addr :: T.Text -> Maybe IPv6Addr
maybeFullIPv6Addr t = do
    a <- maybeTokPureIPv6Addr t
    ipv6TokensToText $ expandTokens $ fromDoubleColon a

-- | Returns Just the canonized 'IPv6Addr' of the given network interface,
-- or Nothing.
--
-- > getIPv6AddrOf "eth0"
--
getIPv6AddrOf :: String -> IO (Maybe IPv6Addr)
getIPv6AddrOf s = do
     l <- networkInterfacesIPv6AddrList
     case lookup s l of
         Just a -> return $ maybeIPv6Addr $ T.pack $ show a
         Nothing -> return Nothing