34 fromEngineMsg msg = liftM (map w2c) (Base64.decode msg >>= removeLength) |
34 fromEngineMsg msg = liftM (map w2c) (Base64.decode msg >>= removeLength) |
35 where |
35 where |
36 removeLength (x:xs) = if length xs == fromIntegral x then Just xs else Nothing |
36 removeLength (x:xs) = if length xs == fromIntegral x then Just xs else Nothing |
37 removeLength _ = Nothing |
37 removeLength _ = Nothing |
38 |
38 |
39 isLegalNetCommand :: String -> Bool |
39 checkNetCmd :: String -> (Bool, Bool) |
40 isLegalNetCommand msg = test decoded |
40 checkNetCmd msg = check decoded |
41 where |
41 where |
42 decoded = fromEngineMsg msg |
42 decoded = fromEngineMsg msg |
43 test Nothing = False |
43 check Nothing = (False, False) |
44 test (Just (m:ms)) = m `Set.member` legalMessages |
44 check (Just (m:ms)) = (m `Set.member` legalMessages, m == '+') |
45 test _ = False |
45 check _ = (False, False) |
46 legalMessages = Set.fromList $ "M#+LlRrUuDdZzAaSjJ,sFNpPwtghb12345" ++ slotMessages |
46 legalMessages = Set.fromList $ "M#+LlRrUuDdZzAaSjJ,sFNpPwtghb12345" ++ slotMessages |
47 slotMessages = "\128\129\130\131\132\133\134\135\136\137\138" |
47 slotMessages = "\128\129\130\131\132\133\134\135\136\137\138" |
48 |
48 |
49 maybeRead :: Read a => String -> Maybe a |
49 maybeRead :: Read a => String -> Maybe a |
50 maybeRead s = case reads s of |
50 maybeRead s = case reads s of |