hangman.hs

module Hangman(
         Hangman,
         createHangman,
         chooseWord,
         playGame) where

   import System.IO(readFile)
   import System.Random
   import Data.Char(isLower)
   import qualified Data.Map as Map
   data Space c = Space c | Unguessed deriving (Show, Eq)

   data Hangman = Hangman { dictwords :: [String], word :: String, rgen :: StdGen, guesses :: Map.Map Char Bool } deriving (Show)
   

   removePossessives :: [String] -> [String]
   removePossessives words = filter (\w -> drop (length w -2) w /= "'s") words
   removeProperNouns :: [String] -> [String]
   removeProperNouns words = filter (isLower . head) words

   getDictionary :: String -> IO [String]
   getDictionary name = do
      c <- readFile $ "/usr/share/dict/" ++ name
      return $ removePossessives $ removeProperNouns $ words c


   createHangman :: IO Hangman
   createHangman = do
      hwords <- getDictionary "american-english"
      gen <- newStdGen
      let word = chooseWord gen hwords
      return Hangman { dictwords = hwords, word = "",  rgen = gen, guesses = Map.fromList _guesses } where
         _guesses = map (\x -> (x, False)) ['a'..'z']

   chooseWord :: StdGen -> [String] -> String
   chooseWord gen words = words !! (rn `mod` (length words)) where 
      rn = head (randoms gen :: [Int])
      

   playGame :: IO () 
   playGame = do
      hng <- createHangman
      gen <- newStdGen
      putStrLn $ chooseWord gen $ dictwords hng
      return ()