{-# LANGUAGE CPP #-}

module OfficialServer.DBInteraction

(

	startDBConnection

) where

import Prelude hiding (catch);

import System.Process

import System.IO

import Control.Concurrent

import Control.Exception

import Control.Monad

import qualified Data.Map as Map

import Monad

import Maybe

import System.Log.Logger

import Data.Time

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

import CoreTypes

import Utils

localAddressList = ["127.0.0.1", "0:0:0:0:0:0:0:1", "0:0:0:0:0:ffff:7f00:1"]

fakeDbConnection serverInfo = do

	q <- readChan $ dbQueries serverInfo

	case q of

		CheckAccount clUid _ clHost -> do

			writeChan (coreChan serverInfo) $ ClientAccountInfo (clUid,

				if clHost `elem` localAddressList then Admin else Guest)

		ClearCache -> return ()

	fakeDbConnection serverInfo

#if defined(OFFICIAL_SERVER)

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

-- borrowed from base 4.0.0 ---------------------------------------

onException :: IO a -> IO b -> IO a                              --

onException io what = io `catch` \e -> do what                   --

                                          throw (e :: Exception) --

-- to be deleted --------------------------------------------------

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

pipeDbConnectionLoop queries coreChan hIn hOut accountsCache = do

	q <- readChan queries

	updatedCache <- case q of

		CheckAccount clUid clNick _ -> do

			let cacheEntry = clNick `Map.lookup` accountsCache

			currentTime <- getCurrentTime

			if (isNothing cacheEntry) || (currentTime `diffUTCTime` (fst . fromJust) cacheEntry > 2 * 24 * 60 * 60) then

				do

					hPutStrLn hIn $ show q

					hFlush hIn

					(clId, accountInfo) <- hGetLine hOut >>= (maybeException . maybeRead)

					writeChan coreChan $ ClientAccountInfo (clId, accountInfo)

					return $ Map.insert clNick (currentTime, accountInfo) accountsCache

				`onException`

					(unGetChan queries q)

				else

				do

					writeChan coreChan $ ClientAccountInfo (clUid, snd $ fromJust cacheEntry)

					return accountsCache

		ClearCache -> return Map.empty

		SendStats {} -> do

			hPutStrLn hIn $ show q

			hFlush hIn

			return accountsCache

	return updatedCache

	where

		maybeException (Just a) = return a

		maybeException Nothing = ioError (userError "Can't read")

pipeDbConnection accountsCache serverInfo = do

	updatedCache <-

		Control.Exception.handle (\e -> warningM "Database" (show e) >> return accountsCache) $ 

			bracket

				(createProcess (proc "./OfficialServer/extdbinterface" []) {std_in = CreatePipe, std_out = CreatePipe})

				(\(_, _, _, processHandle) -> return accountsCache)

				(\(Just hIn, Just hOut, _, _) -> do

				hSetBuffering hIn LineBuffering

				hSetBuffering hOut LineBuffering

				hPutStrLn hIn $ dbHost serverInfo

				hPutStrLn hIn $ dbLogin serverInfo

				hPutStrLn hIn $ dbPassword serverInfo

				pipeDbConnectionLoop (dbQueries serverInfo) (coreChan serverInfo) hIn hOut accountsCache

				)

	threadDelay (5 * 10^6)

	pipeDbConnection updatedCache serverInfo

dbConnectionLoop serverInfo =

		if (not . null $ dbHost serverInfo) then

			pipeDbConnection Map.empty serverInfo

		else

			fakeDbConnection serverInfo

#else

dbConnectionLoop = fakeDbConnection

#endif

startDBConnection serverInfo =

	forkIO $ dbConnectionLoop serverInfo