{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE NamedFieldPuns #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE StandaloneDeriving #-}
{-# OPTIONS_GHC -Wno-orphans #-}
{-# OPTIONS_GHC -fno-warn-ambiguous-fields #-}

module RandomServers where

import Control.Monad (replicateM)
import Data.Foldable (foldMap')
import Data.List (sortOn)
import Data.List.NonEmpty (NonEmpty)
import qualified Data.List.NonEmpty as L
import Data.Monoid (Sum (..))
import Simplex.Chat (defaultChatConfig, randomPresetServers)
import Simplex.Chat.Controller (ChatConfig (..), PresetServers (..))
import Simplex.Chat.Operators (DBEntityId' (..), NewUserServer, UserServer' (..), operatorServers, operatorServersToUse)
import Simplex.Messaging.Agent.Env.SQLite (ServerRoles (..))
import Simplex.Messaging.Protocol (ProtoServerWithAuth (..), SProtocolType (..), UserProtocol)
import Test.Hspec

randomServersTests :: Spec
randomServersTests = describe "choosig random servers" $ do
  it "should choose 4 + 3 random SMP servers and keep the rest disabled" testRandomSMPServers
  it "should choose 3 + 3 random XFTP servers and keep the rest disabled" testRandomXFTPServers

deriving instance Eq ServerRoles

deriving instance Eq (DBEntityId' s)

deriving instance Eq (UserServer' s p)

testRandomSMPServers :: IO ()
testRandomSMPServers = do
  [srvs1, srvs2, srvs3] <-
    replicateM 3 $
      checkEnabled SPSMP 7 False =<< randomPresetServers SPSMP (presetServers defaultChatConfig)
  (srvs1 == srvs2 && srvs2 == srvs3) `shouldBe` False -- && to avoid rare failures

testRandomXFTPServers :: IO ()
testRandomXFTPServers = do
  [srvs1, srvs2, srvs3] <-
    replicateM 3 $
      checkEnabled SPXFTP 6 False =<< randomPresetServers SPXFTP (presetServers defaultChatConfig)
  (srvs1 == srvs2 && srvs2 == srvs3) `shouldBe` False -- && to avoid rare failures

checkEnabled :: UserProtocol p => SProtocolType p -> Int -> Bool -> NonEmpty (NewUserServer p) -> IO [NewUserServer p]
checkEnabled p n allUsed srvs = do
  let srvs' = sortOn server' $ L.toList srvs
      PresetServers {operators = presetOps} = presetServers defaultChatConfig
      presetSrvs = sortOn server' $ concatMap (operatorServers p) presetOps
      Sum toUse = foldMap' (Sum . operatorServersToUse p) presetOps
  srvs' == presetSrvs `shouldBe` allUsed
  map enable srvs' `shouldBe` map enable presetSrvs
  let enbldSrvs = filter (\UserServer {enabled} -> enabled) srvs'
  toUse `shouldBe` n
  length enbldSrvs `shouldBe` n
  pure enbldSrvs
  where
    server' UserServer {server = ProtoServerWithAuth srv _} = srv
    enable :: forall p. NewUserServer p -> NewUserServer p
    enable srv = (srv :: NewUserServer p) {enabled = False}