module Golden where

-- import qualified System.FilePath as Path
-- import qualified Text.Blaze.Utils as Blaze
import Control.Monad (Monad(..))
import Data.Either (Either(..))
import Data.Function (($), (.))
import Data.Functor ((<$>))
import Data.Semigroup (Semigroup(..))
import Data.String (String)
import System.IO (IO)
import Text.Show (Show(..))
import qualified Data.ByteString.Lazy as BS
import qualified Data.List as List
import qualified Data.Text.Lazy as TL
import qualified Data.Text.Lazy.Encoding as TL
import qualified Data.TreeSeq.Strict as TreeSeq
import qualified Text.Blaze.Html.Renderer.Utf8 as Blaze

import Test.Tasty
import Test.Tasty.Golden

import qualified Language.TCT as TCT
import qualified Language.TCT.Debug as TCT
import qualified Language.TCT.Write.HTML5 as TCT.Write.HTML5
import qualified Language.TCT.Write.Plain as TCT.Write.Plain
import qualified Language.TCT.Write.XML as TCT.Write.XML

diff :: String -> String -> [String]
diff ref new = ["diff", "-u", ref, new]

readAST :: String -> IO (Either TCT.ErrorRead TCT.Roots)
readAST inputFile = do
	inp <- BS.readFile inputFile
	return $ TCT.readTrees inputFile $ TL.decodeUtf8 inp

unLeft :: Show err => Either err BS.ByteString -> IO BS.ByteString
unLeft = \case
 Left err -> return $ TL.encodeUtf8 $ TL.pack $ show err
 Right a -> return a

goldensIO :: IO TestTree
goldensIO = do
	inputFiles <- List.sort <$> findByExtension [".tct"] "test/Golden"
	return $
		testGroup "TCT"
		 [ testGroup "AST"
			 [ goldenVsStringDiff inputFile diff (inputFile <> ".ast") $
				(>>= unLeft) $
				readAST inputFile >>= \ast ->
					return $
						TL.encodeUtf8
						 . TL.pack
						 . TCT.runPretty 0
						 <$> ast
			 | inputFile <- inputFiles
			 ]
		 , testGroup "Plain"
			 [ goldenVsStringDiff inputFile diff inputFile $
				(>>= unLeft) $
				readAST inputFile >>= \ast ->
					return $
						TL.encodeUtf8
						 . (<> TL.singleton '\n')
						 . TCT.Write.Plain.document
						 <$> ast
			 | inputFile <- inputFiles
			 ]
		 , testGroup "HTML5"
			 [ goldenVsStringDiff inputFile diff (inputFile <> ".html5") $
				(>>= unLeft) $
				readAST inputFile >>= \ast ->
					return $
						Blaze.renderHtml
						 . TCT.Write.HTML5.document
						 <$> ast
			 | inputFile <- inputFiles
			 ]
		 , testGroup "XML"
			 [ goldenVsStringDiff inputFile diff (inputFile <> ".xml") $
				(>>= unLeft) $
				readAST inputFile >>= \ast ->
					return $
						TL.encodeUtf8
						 . TL.pack
						 . show
						 . TreeSeq.Pretty
						 . TCT.Write.XML.document
						 <$> ast
			 | inputFile <- inputFiles
			 ]
		 ]