content: -- This file is part of the Wire Server implementation.
  --
  -- Copyright (C) 2022 Wire Swiss GmbH <opensource@wire.com>
  --
  -- This program is free software: you can redistribute it and/or modify it under
  -- the terms of the GNU Affero General Public License as published by the Free
  -- Software Foundation, either version 3 of the License, or (at your option) any
  -- later version.
  --
  -- This program is distributed in the hope that it will be useful, but WITHOUT
  -- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  -- FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
  -- details.
  --
  -- You should have received a copy of the GNU Affero General Public License along
  -- with this program. If not, see <https://www.gnu.org/licenses/>.
  
  module Test.Wire.API.Call.Config where
  
  import Data.Aeson
  import Data.Aeson.KeyMap qualified as KeyMap
  import Imports
  import Test.Tasty
  import Test.Tasty.QuickCheck hiding (total)
  import Wire.API.Call.Config (RTCConfiguration, TurnURI, isTcp, isTls, isUdp, limitServers)
  import Wire.Arbitrary ()
  
  tests :: TestTree
  tests =
    testGroup
      "TURN"
      [ testProperty "TurnURI: decode . encode = id" turnURIid,
        testProperty "limitServers/lengthMax" lengthMaxProp,
        testProperty "limitServers/fairness udp" (fairnessProp isUdp),
        testProperty "limitServers/fairness tls" (fairnessProp isTls),
        testProperty "limitServers/fairness tcp" (fairnessProp isTcp),
        testProperty "limitServers/udpPriority" udpPriority,
        testProperty "RTCConfiguration/toJson: sftServersAreNeverNull" sftServersAreNeverNull
      ]
  
  turnURIid :: TurnURI -> Property
  turnURIid t = Just t === (decode . encode) t
  
  lengthMaxProp :: (ZeroToTen, [TurnURI]) -> Property
  lengthMaxProp (ZeroToTen len, uris) = length (limitServers uris len) === min len (length uris)
  
  -- example input:
  --  predicate = isTls
  --  limit = 4
  --  uris  = [udp/tcp/tcp/tcp/tls]
  -- => ensure at least one TLS in output
  fairnessProp :: (TurnURI -> Bool) -> (ZeroToTen, [TurnURI]) -> Bool
  fairnessProp predicate (ZeroToTen len, uris) = do
    let total = length (filter predicate uris)
        returned = length (filter predicate (limitServers uris len))
        expected_min = len `div` 3 -- 3 possible predicates
    total < expected_min || returned >= expected_min
  
  udpPriority :: [TurnURI] -> Bool
  udpPriority uris = do
    let totalUdp = length (filter isUdp uris)
        returnedUdp = length (filter isUdp (limitServers uris 4))
    totalUdp < 2 || returnedUdp >= 2
  
  sftServersAreNeverNull :: RTCConfiguration -> Bool
  sftServersAreNeverNull cfg = case toJSON cfg of
    Object o -> KeyMap.lookup "sft_servers" o /= Just Null
    v -> error . show $ "type mismatch, expected RTCConfiguration to be Object, but got: " <> encode v
  
  newtype ZeroToTen = ZeroToTen Int
    deriving (Eq, Show)
  
  instance Arbitrary ZeroToTen where
    arbitrary = ZeroToTen <$> chooseInt (0, 10)
  