module Happstack.Server.Helpers
    ( smartserver, exactdir, smartserver',getData'
    ) where

import Happstack.Server
import Happstack.State
import System.Environment
import Control.Concurrent
import System.Time
import Control.Monad

-- run the happs server on some port
-- include cookie fix, various other enhancements that make things simpler
smartserver' :: (Methods st, Component st, ToMessage b, Monad m, Functor m) => 
                (m (Maybe (Either Response a, FilterFun Response)) ->
                 IO (Maybe (Either Response b, FilterFun Response))) ->
                Conf -> String -> ServerPartT m a -> Proxy st -> IO ()
smartserver' f conf progName handler stateProxy = withProgName progName $ do
      putStrLn . ( "starting happs server" ++ ) =<< time
      control <- startSystemState stateProxy -- start the HAppS state system

      putStrLn . ( "happs state started" ++ ) =<< time
      tid <- forkIO $ simpleHTTP' f conf handler
      putStrLn . ( ( "simpleHttp started on port " ++ (show . port $ conf) ++ "\n" ++
                 "shut down with ctrl-c" ) ++) =<< time
      waitForTermination
      killThread tid
      putStrLn . ( "creating checkpoint: " ++ ) =<< time
      createCheckpoint control

      putStrLn .  ( "shutting down system: " ++ ) =<< time
      shutdownSystem control 
      putStrLn .  ( "exiting: " ++ ) =<< time
         where time = return . ("\ntime: " ++ ) . show  =<< getClockTime

smartserver :: (Methods st, Component st, ToMessage a) =>
               Conf -> String -> ServerPartT IO a -> Proxy st -> IO ()
smartserver = smartserver' id

exactdir :: (Monad m) => String -> ServerPartT m a -> ServerPartT m a
exactdir staticPath = spsIf (\rq -> rqURL rq == staticPath)

spsIf :: (Monad m) => (Request -> Bool) -> ServerPartT m a -> ServerPartT m a
spsIf p sps = do
  rq <- askRq
  if p rq
    then sps
    else mzero

getData' :: (ServerMonad m, FromData a, MonadPlus m) => m a
getData' = getData >>= maybe mzero return