{-# LANGUAGE OverloadedStrings #-} module Network.PublicSuffixList.Lookup (effectiveTLDPlusOne, effectiveTLDPlusOne', isSuffix, isSuffix') where import qualified Data.Map as M import Data.Maybe (isNothing) import qualified Data.Text as T import qualified Network.PublicSuffixList.DataStructure as DS import Network.PublicSuffixList.Types {-| OffEnd's Bool argument represents whether we fell off a leaf or whether we fell off a non-leaf. True means that we fell off a leaf. Its Text argument is the component that pushed us off the end, along with all the components to the right of that one, interspersed with "."s -} data LookupResult = Inside | AtLeaf | OffEnd Bool T.Text deriving (Eq) {-| This function returns whether or not this domain is owned by a registrar or a regular person. 'Nothing' means that this is a registrar domain; 'Just x' means it's owned by a person. This is used to determine if a cookie is allowed to bet set for a particular domain. For example, you shouldn't be able to set a cookie for \"com\". If the value is 'Just x', then the x value is what is known as the effective TLD plus one. This is one segment more than the suffix of the domain. For example, the eTLD+1 for "this.is.a.subdom.com" is Just "subdom.com" Note that this function expects lowercase ASCII strings. These strings should be gotten from the toASCII algorithm as described in RFC 3490. These strings should not start or end with the \'.\' character, and should not have two \'.\' characters next to each other. (The toASCII algorithm is implemented in the \'idna\' hackage package, though that package doesn't always map strings to lowercase) -} effectiveTLDPlusOne' :: DataStructure -> T.Text -> Maybe T.Text effectiveTLDPlusOne' dataStructure s -- Any TLD is a suffix | length ss == 1 = Nothing | otherwise = output rulesResult exceptionResult where ss = T.splitOn "." s ps = reverse ss exceptionResult = recurse ps [] $ snd dataStructure rulesResult = recurse ps [] $ fst dataStructure -- If we fell off, did we do it at a leaf? Otherwise, what's the -- subtree that we're at getNext :: Tree T.Text -> T.Text -> Either Bool (Tree T.Text) getNext t s' = case M.lookup s' $ children t of Nothing -> Left (M.null $ children t) Just t' -> Right t' getNextWithStar t s' = case getNext t s' of Left _ -> getNext t "*" r -> r recurse :: [T.Text] -> [T.Text] -> Tree T.Text -> LookupResult recurse [] _ t | M.null $ children t = AtLeaf | otherwise = Inside recurse (c : cs) prev t = case getNextWithStar t c of Left b -> OffEnd b $ T.intercalate "." (c : prev) Right t' -> recurse cs (c : prev) t' -- Only match against the exception rules if we have a full match output _ AtLeaf = Just s output _ (OffEnd True x) = Just $ T.intercalate "." $ tail $ T.splitOn "." x -- If we have a subdomain on an existing rule, we're not a suffix output (OffEnd _ x) _ -- A single level domain can never be a eTLD+1 | isNothing $ T.find (== '.') x = Just $ T.intercalate "." $ drop (length ss - 2) ss | otherwise = Just x -- Otherwise, we're a suffix of a suffix, which is a suffix output _ _ = Nothing -- | >>> effectiveTLDPlusOne = effectiveTLDPlusOne' Network.PublicSuffixList.DataStructure.dataStructure effectiveTLDPlusOne :: T.Text -> Maybe T.Text effectiveTLDPlusOne = effectiveTLDPlusOne' DS.dataStructure -- | >>> isSuffix' dataStructure = isNothing . effectiveTLDPlusOne' dataStructure isSuffix' :: DataStructure -> T.Text -> Bool isSuffix' dataStructure = isNothing . effectiveTLDPlusOne' dataStructure -- | >>> isSuffix = isSuffix' Network.PublicSuffixList.DataStructure.dataStructure isSuffix :: T.Text -> Bool isSuffix = isNothing . effectiveTLDPlusOne