Mastermind game in Haskell

Mastermind.hs

module Mastermind
  where
    
import System.Random
import Text.Read
import Data.Maybe
import Data.Char

data Color = Red | Green | Blue | Yellow | Brown | Orange | Black | White deriving (Show, Read, Eq, Ord, Bounded, Enum)

type Combination = [Color]

boolToInt x = if x then 1 else 0

checkWhites:: Combination -> Combination -> Int
checkWhites secret guess =
  sum $ fmap boolToInt $ fmap (\x -> x `elem` secret) guess
 
checkBlacks:: Combination -> Combination -> Int
checkBlacks secret guess =
  let pairs = zip secret guess in
  sum $ fmap boolToInt $ [ x == y | (x,y) <- pairs]

check:: Combination -> Combination -> (Int, Int)
check secret guess = let blacks = checkBlacks secret guess in 
  (checkWhites secret guess -blacks, blacks)
  
parse:: String -> Maybe Combination
parse x = sequence $ fmap (\x -> readMaybe ((toUpper $ head x) : tail x) :: Maybe Color) (words x)

guess:: Combination -> Int -> Combination -> IO ()
guess secret moves guess = do
            let (whites, blacks) = check secret guess
            if blacks == length secret then
                putStrLn "You win! 🎉"
              else do
                 putStrLn ("Result: " ++ show whites ++ " whites " ++ show blacks ++ " blacks. Moves " ++ show (moves-1))
                 turn secret (moves-1)
                 
takeNoRepeats:: (Eq a) => Int -> [a] -> [a] -> [a]
takeNoRepeats n [] [] = []
takeNoRepeats 0 x y = x
takeNoRepeats n x (y:t)
    | y `elem` x = takeNoRepeats n x t
    | otherwise  = let taken = 
                        x ++ [y]
                        in (takeNoRepeats (n-1) taken t)
            
mkguess:: Combination -> Int -> IO ()
mkguess secret moves = do
            putStrLn "\nEnter a guess:"
            string <- getLine
            let userGuess = parse string
            if isJust userGuess then
                  guess secret moves (fromJust userGuess)

            else
                turn secret moves 


randomInList:: StdGen -> [a] -> [a]
randomInList gen allVals = let results = (randomRs (0, (length allVals -1)) gen)
                            in
                              [ allVals !! x | x <- results ]

turn:: Combination -> Int -> IO ()
turn secret moves = if moves == 0 then
              print $ "You lose. 😭" ++ show secret
              else mkguess secret moves
              
        
mastermind:: Int -> Int -> IO()
mastermind len moves = do
              gen <- newStdGen
              let allColors = [ Red .. White]
              putStrLn $ "Available colors: " ++ (show allColors)
              let secret = takeNoRepeats len [] $ randomInList gen allColors
               in do -- print secret
                     turn secret moves