Tweak sound

src/Sound.hs

@@ -15,6 +15,7 @@ import Control.Lens
 playSoundQueue :: SoundData a -> [Int] -> IO ()
 playSoundQueue sd ns = forM_ ns $ \n -> playIfFree (_loadedChunks sd IM.! n) Mix.Once
 
+-- this can be cleaned up
 playIfFree :: Mix.Chunk -> Mix.Times -> IO (Maybe Mix.Channel)
 playIfFree c times = do
     mayChan <- Mix.getAvailable Mix.DefaultGroup
@@ -22,18 +23,33 @@ playIfFree c times = do
         Nothing -> return Nothing
         Just i  -> Just <$> Mix.playOn i times c
 
+playSoundIfFree :: Mix.Chunk -> Sound -> IO (Maybe Sound)
+playSoundIfFree c s = case _soundTime s of
+    Just _  -> (playIfFree c Mix.Forever) >>= return . f
+    Nothing -> playIfFree c Mix.Once    >>= return . f
+  where 
+    f :: Maybe Mix.Channel -> Maybe Sound
+    f = fmap (\chan -> (s & soundChannel .~ Just chan))
+
 haltMaybe :: Maybe Mix.Channel -> IO (Maybe Sound)
 haltMaybe (Just x) = Mix.halt x >> return Nothing
 haltMaybe Nothing = return Nothing
 
+-- logic: check if sound is playing:
+--   if so, decrement timers, and/or stop playing and remove
+--   if not, check if there is free channel:
+--     if so, start playing
+--     if not, remove sound
 playSound :: SoundData a -> Sound -> IO (Maybe Sound)
-playSound sd s
-    | _soundTime s <= 0 = haltMaybe (_soundChannel s)
-    | otherwise = case _soundChannel s of
-        Just i -> return $ Just $ over soundTime (\t -> t - 1) s
-        Nothing -> do maychan <- playIfFree (_loadedChunks sd IM.! _soundType s) Mix.Forever
-                      return $ Just $ s & soundTime -~ 1
-                                        & soundChannel .~ maychan
+playSound sd s = case _soundChannel s of
+    Just i  -> case _soundTime s of
+        Just t | t > 0     -> return $ Just $ set soundTime (Just $ t - 1) s
+               | otherwise -> haltMaybe (_soundChannel s)
+        Nothing -> Mix.playing i >>= (\b -> if b 
+                                            then return (Just s)
+                                            else return Nothing
+                                    )
+    Nothing -> playSoundIfFree (_loadedChunks sd IM.! _soundType s) s
 
 playSounds :: SoundData a -> IO (SoundData a)
 playSounds sd = do