{-# LANGUAGE CPP, DeriveDataTypeable #-}
import Test.Framework (defaultMain, testGroup, Test)
import Test.Framework.Providers.HUnit
import Test.HUnit hiding (Test, assert)

import Data.Typeable (Typeable)
import Control.Monad
import System.Exit
import qualified Control.Exception as Ex
import qualified Control.Concurrent as Concurrent

import qualified UnexceptionalIO as UIO

data CustomException = CustomException deriving (Show, Typeable)
instance Ex.Exception CustomException

class TestClass a where
	testClassMethod :: a -> ()

data CantTestClass = CantTestClass
instance TestClass CantTestClass

data BadRecord = BadRecord { badfld :: String } | OtherBadRecord { otherfld :: String }

fromIOCatches :: IO () -> Assertion
fromIOCatches io = do
	caught <- UIO.run $ UIO.fromIO io
	either
		(const $ return ())
		(\x -> assertFailure $ "fromIO did not catch: " ++ show x)
		caught

fromIOPasses :: IO () -> Assertion
fromIOPasses io = do
	caught <- Ex.try $ UIO.run $ UIO.fromIO io
	either
		(\(Ex.SomeException _) -> return ())
		(\x -> assertFailure $ "fromIO caught: " ++ show x)
		caught

#if MIN_VERSION_base(4,7,0)
threadReturns :: UIO.UIO () -> (Either Ex.SomeException () -> Assertion) -> Assertion
threadReturns spawn assertion = do
	mvar <- Concurrent.newEmptyMVar
	void $ Concurrent.forkFinally (UIO.run spawn >> Concurrent.yield) (Concurrent.putMVar mvar)
	result <- Concurrent.takeMVar mvar
	assertion result

assertRightUnit :: (Show e) => Either e () -> Assertion
assertRightUnit (Left e) = assertFailure $ "Expected Right () got Left " ++ show e
assertRightUnit (Right ()) = return ()

assertLeft :: (e -> Assertion) -> Either e () -> Assertion
assertLeft _ (Right ()) = assertFailure "Expected Left ... got Right ()"
assertLeft assertion (Left e) = assertion e

assertChildThreadError :: Ex.SomeException -> Assertion
assertChildThreadError e = case Ex.fromException e of
	Just (UIO.ChildThreadError _) -> return ()
	Nothing -> assertFailure $ "Expected ChildThreadError got " ++ show e
#endif

tests :: [Test]
tests =
	[
#if MIN_VERSION_base(4,7,0)
		testGroup "fork" [
			testCase "ignores success" (threadReturns
				(void $ UIO.fork $ return ())
				assertRightUnit
			),
			testCase "ignores threadKilled" (threadReturns
				(UIO.fork (forever $ UIO.unsafeFromIO Concurrent.yield) >>= UIO.unsafeFromIO . Concurrent.killThread)
				assertRightUnit
			),
			testCase "re-throws SomeAsyncException" (threadReturns
				(void $ UIO.fork (UIO.unsafeFromIO $ Ex.throwIO Ex.UserInterrupt))
				(assertLeft ((@?= Just Ex.UserInterrupt) . Ex.fromException))
			),
			testCase "re-throws ExitCode" (threadReturns
				(void $ UIO.fork (UIO.unsafeFromIO exitSuccess))
				(assertLeft ((@?= Just ExitSuccess) . Ex.fromException))
			),
			testCase "wraps sync PseudoException in ChildThreadError" (threadReturns
				(void $ UIO.fork (error "blah"))
				(assertLeft assertChildThreadError)
			)
		],
#endif
		testGroup "fromIO catches runtime errors" [
			testCase "fail" (fromIOCatches $ fail "boo"),
			testCase "userError" (fromIOCatches $ Ex.throwIO $ userError "boo"),
			testCase "CustomException" (fromIOCatches $ Ex.throwIO CustomException)
		],
		testGroup "fromIO passes through programmer errors" [
#if MIN_VERSION_base(4,9,0)
			testCase "TypeError" (fromIOPasses $ Ex.throwIO $ Ex.TypeError "boo"),
#endif
			testCase "error" (fromIOPasses $ error "boo"),
			testCase "undefined" (fromIOPasses undefined),
			testCase "ArithException" (fromIOPasses $ void (return $! (1::Int) `div` 0)),
			testCase "assert" (fromIOPasses $ Ex.assert False (return ())),
			testCase "pattern match fail" (fromIOPasses $ (\(Just _) -> return ()) Nothing),
			testCase "array out of bounds" (fromIOPasses $ Ex.throwIO $ Ex.IndexOutOfBounds "boo"),
			testCase "array uninitialized" (fromIOPasses $ Ex.throwIO $ Ex.UndefinedElement "boo"),
			testCase "no method" (fromIOPasses $ print $ testClassMethod CantTestClass),
			testCase "use uninitialized record field" (fromIOPasses $ print $ badfld BadRecord {}),
			testCase "use not present record field" (fromIOPasses $ print $ otherfld BadRecord {}),
			testCase "update not present record field" (fromIOPasses $ void (return $! (BadRecord {} { otherfld = "hai" })))
		],
		testGroup "fromIO passes through termination" [
#if MIN_VERSION_base(4,8,0)
			testCase "die" (fromIOPasses $ die "exit time"),
#endif
			testCase "exitSuccess" (fromIOPasses exitSuccess),
			testCase "exitFailure" (fromIOPasses exitFailure)
		],
		testGroup "fromIO passes through exceptions from the runtime" [
#if MIN_VERSION_base(4,8,0)
			testCase "AllocationLimitExceeded" (fromIOPasses $ Ex.throwIO Ex.AllocationLimitExceeded),
#endif
#if MIN_VERSION_base(4,7,0)
			testCase "ChildThreadError" (fromIOPasses $ Ex.throwIO $ UIO.ChildThreadError $ UIO.ProgrammerError $ UIO.ArithException Ex.DivideByZero),
#endif
			testCase "NonTermination" (fromIOPasses $ Ex.throwIO Ex.NonTermination),
			testCase "StackOverflow" (fromIOPasses $ Ex.throwIO Ex.StackOverflow),
			testCase "HeapOverflow" (fromIOPasses $ Ex.throwIO Ex.HeapOverflow),
			testCase "ThreadKilled" (fromIOPasses $ Ex.throwIO Ex.ThreadKilled),
			testCase "UserInterrupt" (fromIOPasses $ Ex.throwIO Ex.UserInterrupt),
			testCase "BlockedIndefinitelyOnMVar" (fromIOPasses $ Ex.throwIO Ex.BlockedIndefinitelyOnMVar),
			testCase "BlockedIndefinitelyOnSTM" (fromIOPasses $ Ex.throwIO Ex.BlockedIndefinitelyOnSTM),
			testCase "Deadlock" (fromIOPasses $ Ex.throwIO Ex.Deadlock),
			testCase "NestedAtomically" (fromIOPasses $ Ex.throwIO Ex.NestedAtomically)
		]
	]

main :: IO ()
main = defaultMain tests