module TestHeaders where

import Data.ByteString (ByteString)
import Data.CaseInsensitive (mk)
import Network.HTTP.Client (method)
import Servant
import Servant.API.HeaderList
import Test.QuickCheck.Monadic (PropertyM (..), assert, monadicIO)
import Test.Tasty
import TestLib (returns400, success)

import qualified Network.HTTP.Simple as S
import qualified Network.HTTP.Types.Header as NTH
import qualified Test.Tasty.QuickCheck as QC

myHeaderList :: [NTH.Header]
myHeaderList =
  [
    ( (mk "MerlinWasHere" :: NTH.HeaderName)
    , "TEST_COOKIE=FOOBAR"
    )
  ,
    ( (mk "OtherHeader" :: NTH.HeaderName)
    , "FOOBAR"
    )
  ]

type HeaderAPI =
  "check-headers"
    :> HeaderList
    :> Get '[JSON] NoContent

headerServer :: Server HeaderAPI
headerServer = checkHeader
  where
    checkHeader :: [NTH.Header] -> Handler NoContent
    checkHeader headers = do
      let headerIntersection = all (\a -> elem a headers) myHeaderList
      case headerIntersection of
        True -> do
          pure NoContent
        False -> do
          throwError err400

headerProps :: Int -> TestTree
headerProps port =
  testGroup
    "HeaderList"
    [ QC.testProperty "The endpoint should error with no headers present" $
        monadicIO $ do
          result <- (fetchHeaderEndpoint port Nothing) >>= returns400
          assert $ result == True
    , QC.testProperty "The endpoint should return a 200 if a header is added" $
        monadicIO $ do
          result <- (fetchHeaderEndpoint port (Just $ myHeaderList)) >>= success
          assert $ result == True
    ]
  where
    fetchHeaderEndpoint :: Int -> Maybe [NTH.Header] -> PropertyM IO (S.Response ByteString)
    fetchHeaderEndpoint port' mHeaderList =
      let
        initReq =
          S.parseRequest_ $
            "http://localhost:"
              <> (show port')
              <> "/check-headers"
        headerList = maybe [] id mHeaderList
        reqHeader = S.setRequestHeaders headerList initReq
        req = reqHeader {method = "GET"}
      in
        do
          resp <- S.httpBS req
          pure resp