_

_.hs

-- | You can follow the progress here: https://github.com/Palmik/wai-sockjs/

import           Control.Monad.IO.Class
import           Control.Concurrent.MVar.Lifted
import           Data.Conduit
import           Data.Proxy
import qualified Data.HashMap.Strict as HM
import qualified Data.Text as T
import qualified Data.ByteString as B
import qualified Network.Wai as W

------------------------------------------------------------------------------
-- | Application (server application, such as the example echo) related stuff

type Application m =  Source m B.ByteString  -- ^ Source for incoming messages (_ => Application)
                   -> Sink B.ByteString m () -- ^ Sink for outgoing messages (Application => _)
                   -> m ()

------------------------------------------------------------------------------
-- | Session related stuff

type SessionID = T.Text

-- | Session contains all the neccessary timers, buffers (downstream and upstream), status flags, etc.
--   Session should also be tagged by specific transport.
data Session = Session

newtype Environment = Environment { unEnvironment ::  MVar (HM.HashMap SessionID (MVar Session)) }

newSession :: MonadBase IO m
           => SessionID
           -> m Session
newSession = undefined

addSession :: MonadBaseControl IO m
           => SessionID
           -> Session
           -> Environment
           -> m ()
addSession = undefined

modifySession :: MonadBaseControl IO m
              => (Session -> Session)
              -> SessionID
              -> Environment
              -> m ()
modifySession = undefined

-- | Retrieves session with the given ID (if there is no such session, it's created first)
getSession :: MonadBaseControl IO m
           => SessionID
           -> Environmnet
           -> MVar Session
getSession = undefined

------------------------------------------------------------------------------
-- | Frame related stuff

data Frame = Frame -- nothing unusual here

------------------------------------------------------------------------------
-- | Transport related stuff

class Transport tag where
    -- | Used for _ => Application communication.
    -- The request is checked whether it conforms the transport's rules and is then saved to a buffer.
    -- The '_' could stand for e.g. some web app communication with out server Application
    handleIncoming :: MonadBaseControl IO m
                   => Proxy tag
                   -> Evironment -- Or we could use simply Session, if it turns out, that we can handle session creation globally.
                   -> W.Request
                   -> m ()

    -- | Used for Application => _ communication
    -- The frame is checked whether it conforms the transport's rules and is then send (no buffering here).
    -- The '_' could stand for e.g. some web app communication with out server Application
    send :: MonadBaseControl IO m
         => Proxy tag
         -> Frame
         -> m ()

------------------------------------------------------------------------------
-- | Handler related stuff

-- | Internally uses Transport's send (potentially hidden behind some intermediate buffer).
sessionSink :: MonadBaseControl IO m
            => Session
            -> Sink B.ByteString m ()
sessionSink = undefined

-- | Internally uses the Session's buffer (which was written into by Transport's handleIncoming)
sessionSource :: MonadBaseControl IO m
              => Session
              -> Source m B.ByteString
sessionSource = undefined

runApplication :: MonadBaseControl IO m
               => Application m
               -> Session
               -> m ()
runApplication = undefined

--
main = undefined