{-# LANGUAGE StandaloneDeriving, LambdaCase #-}
module Main where

import Control.Concurrent (killThread, forkIO)
import Control.Monad (Monad(..), mapM)
import Data.Aeson
import qualified Data.ByteString.Lazy.Char8 as BS (unpack)
import qualified Data.List as List ((++), map)
import Data.Maybe (Maybe(..))
import Network.WebSockets
import System.IO (IO(..))
import Test.Tasty
import Test.Tasty.HUnit (assertEqual, assertBool, testCase)

import Language.Haskell.Tools.Demo (ResponseMsg(..), ClientMessage(..), runDemo)

main :: IO ()
main = do -- create one daemon process for the whole testing session
          -- with separate processes it is not a problem
          threadId <- forkIO $ runDemo []
          defaultMain allTests
          killThread threadId

allTests :: TestTree
allTests
  = localOption (mkTimeout ({- 10s -} 1000 * 1000 * 10))
      $ testGroup "daemon-tests"
          [ testGroup "simple-tests" $ map makeDemoTest simpleTests
          , testGroup "loading-tests" $ map makeDemoTest loadingTests
          , testGroup "refactor-tests" $ map makeDemoTest refactorTests
          , astViewTest
          ]

simpleTests :: [(String, [ClientMessage], [ResponseMsg])]
simpleTests =
  [ ( "empty-test", [], [] )
  , ( "keep-alive", [KeepAlive], [] )
  ]

loadingTests :: [(String, [ClientMessage], [ResponseMsg])]
loadingTests =
  [ ( "one-module"
    , [InitialProject [("A", "module A where\n\na = ()")]]
    , [] )
  , ( "multi-modules"
    , [InitialProject [("A", "module A where\n\na = ()"), ("B", "module B where\n\nimport A\n\nb = a")]]
    , [] )
  , ( "multi-modules-wrong-order"
    , [InitialProject [("B", "module B where\n\nimport A\n\nb = a"), ("A", "module A where\n\na = ()")]]
    , [] )
  , ( "multi-modules-added-later"
    , [ InitialProject [("A", "module A where\n\na = ()")]
      , ModuleChanged "B" "module B where\n\nimport A\n\nb = a" ]
    , [] )
  , ( "comp-problem"
    , [InitialProject [("A", "module A where\n\na = noSuchVar")]]
    , [CompilationProblem "A.hs 3:5\nVariable not in scope: noSuchVar\n\n"] )
  ]

refactorTests :: [(String, [ClientMessage], [ResponseMsg])]
refactorTests =
  [ ( "simple-refactor"
    , [ InitialProject [("A", "module A where\n\na = ()")]
      , PerformRefactoring "RenameDefinition" "A" "3:1-3:2" ["x"] ]
    , [ RefactorChanges [("A", Just "module A where\n\nx = ()")] ] )
  , ( "multi-module-refactor"
    , [ InitialProject [("A", "module A where\n\na = ()"), ("B", "module B where\n\nimport A\n\nb = a")]
      , PerformRefactoring "RenameDefinition" "A" "3:1-3:2" ["x"] ]
    , [ RefactorChanges [("A", Just "module A where\n\nx = ()"), ("B", Just "module B where\n\nimport A\n\nb = x")] ] )
  , ( "multi-module-refactor-user-added-later"
    , [ InitialProject [("A", "module A where\n\na = ()")]
      , ModuleChanged "B" "module B where\n\nimport A\n\nb = a"
      , PerformRefactoring "RenameDefinition" "A" "3:1-3:2" ["x"] ]
    , [ RefactorChanges [("A", Just "module A where\n\nx = ()"), ("B", Just "module B where\n\nimport A\n\nb = x")] ] )
  , ( "multi-module-refactor-both-added-later"
    , [ InitialProject [("B", "module B where")]
      , ModuleChanged "A" "module A where\n\na = ()"
      , ModuleChanged "B" "module B where\n\nimport A\n\nb = a"
      , PerformRefactoring "RenameDefinition" "A" "3:1-3:2" ["x"] ]
    , [ RefactorChanges [("A", Just "module A where\n\nx = ()"), ("B", Just "module B where\n\nimport A\n\nb = x")] ] )
  , ( "rename-module"
    , [ InitialProject [("A", "module A where\n\na = ()")]
      , PerformRefactoring "RenameDefinition" "A" "1:8-1:9" ["AA"] ]
    , [ RefactorChanges [("AA", Just "module AA where\n\na = ()"), ("A", Nothing)] ] )
  , ( "change-module"
    , [ InitialProject [("A", "module A where\n\na = ()")]
      , ModuleChanged "A" "module A where\n\n\na = ()"
      , PerformRefactoring "RenameDefinition" "A" "4:1-4:2" ["x"] ]
    , [ RefactorChanges [("A", Just "module A where\n\n\nx = ()")] ] )
  , ( "removed-module"
    , [ InitialProject [("A", "module A where\n\na = ()"), ("B", "module B where\n\nimport A\n\nb = a")]
      , ModuleDeleted "B"
      , PerformRefactoring "RenameDefinition" "A" "3:1-3:2" ["x"] ]
    , [ RefactorChanges [("A", Just "module A where\n\nx = ()")] ] )
  ]

makeDemoTest :: (String, [ClientMessage], [ResponseMsg]) -> TestTree
makeDemoTest (label, input, expected) = testCase label $ do
    actual <- communicateWithDemo input
    assertEqual "" expected actual

astViewTest :: TestTree
astViewTest = testCase "ast-view-test" $ do
    actual <- communicateWithDemo [ InitialProject [("A", "module A where\n\na = ()")]
                                  , PerformRefactoring "UpdateAST" "A" "1:1" [] ]
    assertBool "The response must be a simple ASTViewContent message"
      $ case actual of [ ASTViewContent _ ] -> True
                       _                    -> False

communicateWithDemo :: [ClientMessage] -> IO [ResponseMsg]
communicateWithDemo msgs = runClient "127.0.0.1" 8206 "/" $ \conn -> do
  mapM (sendTextData conn . encode) (msgs ++ [Disconnect])
  receiveAllResponses conn

receiveAllResponses :: Connection -> IO [ResponseMsg]
receiveAllResponses conn = do
  Text mess <- receiveDataMessage conn
  let decoded = decode mess
  case decoded of Just Disconnected -> return []
                  Just other -> (other :) <$> receiveAllResponses conn
                  _ -> error ("Unrecognized response: " ++ BS.unpack mess)

deriving instance Eq ResponseMsg
instance FromJSON ResponseMsg
instance ToJSON ClientMessage