{-# LANGUAGE OverloadedStrings #-}

module Utils where

import Data.Char

import Data.Word

import qualified Data.Map as Map

import qualified Data.Set as Set

import Numeric

import Network.Socket

import System.IO

import qualified Data.List as List

import Control.Monad

-------------------------------------------------

import qualified Codec.Binary.Base64 as Base64

import qualified Data.ByteString.Char8 as B

import qualified Data.ByteString as BW

import CoreTypes

sockAddr2String :: SockAddr -> IO B.ByteString

sockAddr2String (SockAddrInet _ hostAddr) = liftM B.pack $ inet_ntoa hostAddr

sockAddr2String (SockAddrInet6 _ _ (a, b, c, d) _) =

    return $ B.pack $ (foldr1 (.)

        $ List.intersperse (':':)

        $ concatMap (\n -> (\(a0, a1) -> [showHex a0, showHex a1]) $ divMod n 65536) [a, b, c, d]) []

toEngineMsg :: B.ByteString -> B.ByteString

toEngineMsg msg = B.pack $ Base64.encode (fromIntegral (BW.length msg) : BW.unpack msg)

fromEngineMsg :: B.ByteString -> Maybe B.ByteString

fromEngineMsg msg = liftM BW.pack (Base64.decode (B.unpack msg) >>= removeLength)

    where

        removeLength (x:xs) = if length xs == fromIntegral x then Just xs else Nothing

        removeLength _ = Nothing

checkNetCmd :: B.ByteString -> (Bool, Bool)

checkNetCmd = check . liftM B.unpack . fromEngineMsg

    where

        check Nothing = (False, False)

        check (Just (m:_)) = (m `Set.member` legalMessages, m == '+')

        check _ = (False, False)

        legalMessages = Set.fromList $ "M#+LlRrUuDdZzAaSjJ,sFNpPwtghb12345" ++ slotMessages

        slotMessages = "\128\129\130\131\132\133\134\135\136\137\138"

maybeRead :: Read a => String -> Maybe a

maybeRead s = case reads s of

    [(x, rest)] | all isSpace rest -> Just x

    _         -> Nothing

teamToNet :: TeamInfo -> [B.ByteString]

teamToNet team =

        "ADD_TEAM"

        : teamname team

        : teamgrave team

        : teamfort team

        : teamvoicepack team

        : teamflag team

        : teamowner team

        : (B.pack . show $ difficulty team)

        : hhsInfo

    where

        hhsInfo = concatMap (\(HedgehogInfo n hat) -> [n, hat]) $ hedgehogs team

modifyTeam :: TeamInfo -> RoomInfo -> RoomInfo

modifyTeam team room = room{teams = replaceTeam team $ teams room}

    where

    replaceTeam _ [] = error "modifyTeam: no such team"

    replaceTeam tm (t:ts) =

        if teamname tm == teamname t then

            tm : ts

        else

            t : replaceTeam tm ts

illegalName :: B.ByteString -> Bool

illegalName b = null s || all isSpace s || isSpace (head s) || isSpace (last s)

    where

        s = B.unpack b

protoNumber2ver :: Word16 -> B.ByteString

protoNumber2ver v = Map.findWithDefault "Unknown" v vermap

    where

        vermap = Map.fromList [

askFromConsole :: B.ByteString -> IO B.ByteString

askFromConsole msg = do

    B.putStr msg

    hFlush stdout

    B.getLine

unfoldrE :: (b -> Either b (a, b)) -> b -> ([a], b)

unfoldrE f b  =

    case f b of

        Right (a, new_b) -> let (a', b') = unfoldrE f new_b in (a : a', b')

        Left new_b       -> ([], new_b)

showB :: Show a => a -> B.ByteString

showB = B.pack .show