module Data.SMTP.Parser.Host (scanHostName, parseHostName) where

import Data.SMTP.Types.Account

import Data.Attoparsec.ByteString.Char8
import qualified Data.Attoparsec.ByteString.Char8 as A
import Data.ByteString (ByteString)
import qualified Data.Char as C

parseHostName :: Parser HostName
parseHostName = do
  h <- scanHostName
  return . HostName $ h

scanHostName :: Parser ByteString
scanHostName = A.takeWhile isHostChar

isHostChar :: Char -> Bool
isHostChar c
  | c `elem` ("._-" :: String) = True
  | C.isSpace c = False
  | C.isAlphaNum c = True
  | otherwise = False