{-# OPTIONS_GHC -fno-warn-warnings-deprecations #-}

{-# LANGUAGE CPP #-}
{-# LANGUAGE OverloadedStrings #-}

module Snap.Util.CORS.Tests (tests) where

------------------------------------------------------------------------------
import           Data.ByteString.Char8          (ByteString)
import           Data.CaseInsensitive           (CI (..))
#if !MIN_VERSION_base(4,8,0)
import           Data.Functor                   ((<$>))
#endif
import qualified Data.HashSet                   as HashSet
import qualified Data.Set                       as Set
import qualified Data.Text                      as Text
import qualified Data.Text.Encoding             as Text
import           Snap.Core                      (Method (..), getHeader, Response(..))
import           Snap.Test                      (RequestBuilder, runHandler, setHeader, setRequestType, RequestType(..), setRequestPath)
import           Snap.Util.CORS                 (applyCORS,CORSOptions(..),defaultOptions,HashableMethod(..))
import           Test.Framework                 (Test)
import           Test.Framework.Providers.HUnit (testCase)
import           Test.HUnit                     (assertEqual,Assertion)
------------------------------------------------------------------------------


------------------------------------------------------------------------------
tests :: [Test]
tests = [ testCORSSimple
        , testCORSOptions
        ]


                                ---------------
                                -- Constants --
                                ---------------

------------------------------------------------------------------------------
origin :: ByteString
origin = "http://origin.org"



                                  -----------
                                  -- Tests --
                                  -----------

------------------------------------------------------------------------------
testCORSSimple :: Test
testCORSSimple = testCase "CORS/simple" $ do
    let testDefault meth = do
          r <- runHandler (mkMethReq meth) $
               applyCORS defaultOptions $ return ()
          checkAllowOrigin (Just origin) r
          checkAllowCredentials (Just "true") r
          checkExposeHeaders Nothing r
    mapM_ testDefault [GET,POST,PUT,DELETE,HEAD]

------------------------------------------------------------------------------
testCORSOptions :: Test
testCORSOptions = testCase "CORS/options" $ do
  let opts = applyCORS defaultOptions { corsAllowedMethods =
               return $ HashSet.singleton $ HashableMethod GET  }
  r <- runHandler (mkMethReq OPTIONS
                   >> setRequestMethod "GET"
                   >> setRequestHeaders "X-STUFF, Content-Type") $
       opts $ return ()
  checkAllowOrigin (Just origin) r
  checkAllowCredentials (Just "true") r
  checkAllowHeaders (Just "Content-Type, X-STUFF") r
  checkAllowMethods (Just "GET") r
  ---------------------------------------------------------
  s <- runHandler (mkMethReq OPTIONS
                   >> setRequestMethod "POST"
                   >> setRequestHeaders "X-STUFF, Content-Type") $
       opts $ return ()
  checkAllowOrigin Nothing s
  checkAllowCredentials Nothing s
  checkAllowHeaders Nothing s
  checkAllowMethods Nothing s


                                ---------------
                                -- Functions --
                                ---------------

------------------------------------------------------------------------------
mkMethReq :: Method -> RequestBuilder IO ()
mkMethReq meth = do
  setRequestType $ RequestWithRawBody meth ""
  setRequestPath "/"
  setHeader "Origin" origin

checkHeader :: CI ByteString -> Maybe ByteString -> Response -> Assertion
checkHeader h v r = assertEqual ("Header " ++ show h) v (getHeader h r)

checkAllowOrigin :: Maybe ByteString -> Response -> Assertion
checkAllowOrigin = checkHeader "Access-Control-Allow-Origin"

checkAllowCredentials :: Maybe ByteString -> Response -> Assertion
checkAllowCredentials = checkHeader "Access-Control-Allow-Credentials"

checkExposeHeaders :: Maybe ByteString -> Response -> Assertion
checkExposeHeaders = checkHeader "Access-Control-Expose-Headers"

checkAllowHeaders :: Maybe ByteString -> Response -> Assertion
checkAllowHeaders v r =
  assertEqual "Header Access-Control-Allow-Headers"
    (getSet <$> v)
    (getSet <$> getHeader "Access-Control-Allow-Headers" r)
  where
    getSet = Set.fromList . Text.splitOn ", " . Text.decodeUtf8

checkAllowMethods :: Maybe ByteString -> Response -> Assertion
checkAllowMethods = checkHeader "Access-Control-Allow-Methods"

setRequestMethod :: ByteString -> RequestBuilder IO ()
setRequestMethod = setHeader "Access-Control-Request-Method"

setRequestHeaders :: ByteString -> RequestBuilder IO ()
setRequestHeaders = setHeader "Access-Control-Request-Headers"