Go Fish/Haskell

Go Fish/Haskell is part of Go Fish. You may find other members of Go Fish at Category:Go Fish.

If possible, the AI will randomly select a rank known to be in the human's hand (a card in the AI's hand that the human has asked for before and the AI hasn't asked for before). If there are no known ranks, a rank is randomly selected from the AI's hand.

<lang haskell> import Char import IO import Data.Map (Map) import qualified Data.Map as M import Data.Set (Set) import qualified Data.Set as S import Data.List import Monad import Random

data Player = Player String (GameState -> IO Rank)

type PlayerState = (Hand, Set Rank, Set Rank)

data GameState = GS [(Suit, Rank)] PlayerState PlayerState

type Hand = Map Rank (Set Suit)

data Suit = Diamond | Club | Heart | Spade

           deriving (Bounded, Enum, Eq, Ord, Show)

data Rank = Two | Three | Four | Five | Six | Seven | Eight | Nine | Ten |

           Jack | Queen | King | Ace
           deriving (Bounded, Enum, Eq, Ord, Show)

main =

   hSetBuffering stdout NoBuffering >>
   putStrLn "GO FISH\n\nDealing Cards" >>
   initialGameState >>=
   play (cycle [player, computer])

play ((Player name next):ps) state =

   putStrLn ('\n' : name ++ "'S TURN") >>
   runPlayer next state >>= \nextState ->
   (if isDone nextState
    then let (winnerName, ws, ls) = scoreGame name (head ps) nextState
         in putStrLn (winnerName ++ " WINS " ++ show ws ++ " TO " ++ show ls)
    else play ps $ swapPlayers nextState
   )

scoreGame name (Player opp _) (GS _ (_,books,_) (_,oppBooks,_)) =

   if score > oppScore then (name,score,oppScore) else (opp,oppScore,score)
   where (score, oppScore) = (S.size books, S.size oppBooks)

player = Player "PLAYER" playerBrain playerBrain (GS _ (hand,_,_) _) =

   putStr "Your cards: " >>
   putStrLn (intercalate " " . map showCard $ handToCards hand) >>
   untilSuccess (liftM readRank rankPrompt) (putStrLn "Bad rank")
   where rankPrompt = putStr "Ask opponent for what rank? " >> getLine

computer = Player "COMPUTER" computerBrain computerBrain (GS _ (hand,_,history) (_, _, oppHistory)) =

   liftM selectRank newStdGen >>= \rank ->
   putStrLn ("Do you have any " ++ show rank ++ "s?") >>
   return rank
   where knowns = S.difference (S.intersection guesses oppHistory) history
         guesses = M.keysSet hand
         ranks = S.toList $ if S.null knowns then guesses else knowns
         selectRank = (ranks !!) . fst . randomR (0, length ranks - 1)

runPlayer askRank state@(GS deck (hand, b, hi) o) =

   if M.null hand
   then if null deck
        then return $! state
        else putStrLn "Empty hand, forced draw" >>
             let (newHand, newDeck) = draw hand deck
             in normalizeBooks $ GS newDeck (newHand, b, hi) o
   else getValidRank askRank state >>= \rank ->
        exchangeCards state rank >>= \(newState, done) ->
        normalizeBooks newState >>=
        (if done then return else runPlayer askRank)

exchangeCards (GS deck (hand, b, hist) (opponentHand, ob, ohi)) rank =

   putStrLn m >> return (GS nd (nh, b, nhi) (noh, ob, ohi), done)
   where (m, nh, noh, nd, done) = worker $ M.lookup rank opponentHand
         nhi = S.insert rank hist
         worker Nothing = ("Go fish", newHand, opponentHand, newDeck, True)
             where (newHand, newDeck) = draw hand deck
         worker (Just suits) = (message, newHand, newOppHand, deck, False)
             where message = show (S.size suits) ++ " " ++ show rank ++ "(s)"
                   newHand = M.adjust (S.union suits) rank hand
                   newOppHand = M.delete rank opponentHand

getValidRank askRank state@(GS _ (hand,_,_) _) = untilSuccess

   (liftM (check hand) $ askRank state) $ putStrLn "Rank not in hand"
   where check m v = M.lookup v m >>= Just . const v

normalizeBooks (GS d (hand, books, hi) o) =

   mapM_ printRank (M.keys newBookRanks) >>
   (return $! GS d (newHand, newBooks, hi) o)
   where (newBookRanks, newHand) = M.partition ((==4) . S.size) hand
         newBooks = S.union books $ M.keysSet newBookRanks
         printRank r = putStrLn ("Rank " ++ show r ++ " was booked")

swapPlayers (GS d p1 p2) = GS d p2 p1

isDone (GS deck (hand,_,_) (oppHand,_,_)) =

   and [M.null hand, M.null oppHand, null deck]

initialGameState = liftM worker newStdGen

   where worker gen =
             (GS deck (hand1, S.empty, S.empty) (hand2, S.empty, S.empty))
             where (startDeck, _) = shuffle initialDeck gen
                   (hand1, deckMinusPlayerHand) = drawN 9 M.empty startDeck
                   (hand2, deck) = drawN 9 M.empty deckMinusPlayerHand

untilSuccess action onFailure = worker

   where worker = action >>= \result -> case result of
             Nothing -> onFailure >> worker
             Just value -> return $! value

readRank [x] | isDigit x && x > '1' = Just $ toEnum (fromEnum x - 50) readRank x@[_,_] | x == "10" = Just Ten readRank [x] = case toLower x of

   'j' -> Just Jack
   'q' -> Just Queen
   'k' -> Just King
   'a' -> Just Ace
   _   -> Nothing

readRank _ = Nothing

showCard (suit, rank) = r ++ front suit

   where r = if rank > Ten then front rank else show (fromEnum rank + 2)
         front v = [head $ show v]

initialDeck = liftM2 (,) [Diamond .. Spade] [Two .. Ace]

shuffle deck gen = worker gen (length deck) [] deck

   where worker g l xs [] = (xs, g)
         worker g l xs ys = worker newGen (l-1) (card : xs) (delete card ys)
             where (index, newGen) = randomR (0,l-1) g
                   card = ys !! index

draw hand ((s,r):deck) = (M.insertWith S.union r (S.singleton s) hand, deck)

drawN n hand deck = iterate (uncurry draw) (hand, deck) !! (n-1)

handToCards = concatMap (\(r,ss) -> map (flip (,) r) $ S.toList ss) . M.assocs </lang>