import Paths_utf8_prelude

import Data.Maybe

import qualified Prelude
import UTF8Prelude

----------------------

writeFile_test :: String
writeFile_test = "writeFile_test.txt"

main :: IO ()
main = do
    do
        s <- do
            readFile_test <- getDataFileName "readFile_test.txt"
            s <- readFile readFile_test 
            let errors = catMaybes $ map checkLine $ lines s
            assert (null errors) "readFile" $ head errors
            return s

        do
            writeFile writeFile_test s
            s' <- readFile writeFile_test 
            let diffs = filter (\(a,b) -> a /= b) $ zip s s'
            assert (null diffs) "writeFile" $ "First 10 different charcodes: " ++ show (take 10 diffs)

    do
        putStrLn "Basic putStrLn test:"
        putStrLn_test <- getDataFileName "putStrLn_test.txt"
        s <- readFile putStrLn_test
        mapM_ putStrLn $ map ("  " ++) $ lines s


checkLine :: String -> Maybe String
checkLine s = case reads s of
    [(i, [' ',c])]
        | i == fromEnum c -> Nothing
    [(i, ' ':cs)]
        | otherwise -> Just $ "\"\\" ++ show i ++ "\" /= \"" ++ cs ++ "\""
    _  -> Just $ "Fatal error: Invalid line in testfile: " ++ s

assert :: Bool -> String -> String -> IO ()
assert True t _ = putStrLn $ t ++ " test OK."
assert False t s = error $ t ++ " test failed! " ++ s

make_readFile_test :: IO ()
make_readFile_test = writeFile "readFile_test.txt" $ unlines [show i ++ " " ++ [toEnum i] | i<-[33,132..55000]]
-- it fails with [33,132..65535]!