#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
#Copyright (C) 2015: Edouard TISSERANT
#
#See COPYING file for copyrights details.
#
#This library is free software; you can redistribute it and/or
#modify it under the terms of the GNU General Public
#License as published by the Free Software Foundation; either
#version 2.1 of the License, or (at your option) any later version.
#
#This library is distributed in the hope that it will be useful,
#but WITHOUT ANY WARRANTY; without even the implied warranty of
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
#General Public License for more details.
#
#You should have received a copy of the GNU General Public
#License along with this library; if not, write to the Free Software
#Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

import sys, traceback
#from twisted.python import log
from twisted.internet import reactor, threads
from autobahn.twisted import wamp
from autobahn.twisted.websocket import WampWebSocketClientFactory, connectWS
from autobahn.wamp import types
from autobahn.wamp.exception import TransportLost
from autobahn.wamp.serializer import MsgPackSerializer
from threading import Thread, Event

_WampSession = None
_ReactorThread = None
_WampSessionEvent = Event()

class WampSession(wamp.ApplicationSession):
    def onJoin(self, details):
        global _WampSession
        _WampSession = self
        _WampSessionEvent.set()
        print 'WAMP session joined for :', self.config.extra["ID"]

    def onLeave(self, details):
        global _WampSession
        _WampSessionEvent.clear()
        _WampSession = None
        print 'WAMP session left'

PLCObjDefaults = { "StartPLC": False,
                   "GetTraceVariables" : ("Broken",None),
                   "GetPLCstatus" : ("Broken",None),
                   "RemoteExec" : (-1, "RemoteExec script failed!")}

def WAMP_connector_factory(uri, confnodesroot):
    """
    WAMP://127.0.0.1:12345/path#realm#ID
    WAMPS://127.0.0.1:12345/path#realm#ID
    """
    global _WampSession, _ReactorThread, _WampSessionEvent

    servicetype, location = uri.split("://")
    urlpath, realm, ID = location.split('#')
    urlprefix = {"WAMP":"ws",
                 "WAMPS":"wss"}[servicetype]
    url = urlprefix+"://"+urlpath

    def RegisterWampClient():

        ## start logging to console
        # log.startLogging(sys.stdout)

        # create a WAMP application session factory
        component_config = types.ComponentConfig(
            realm = realm,
            extra = {"ID":ID})
        session_factory = wamp.ApplicationSessionFactory(
            config = component_config)
        session_factory.session = WampSession

        # create a WAMP-over-WebSocket transport client factory
        transport_factory = WampWebSocketClientFactory(
            session_factory,
            url = url,
            serializers = [MsgPackSerializer()],
            debug = False,
            debug_wamp = False)

        # start the client from a Twisted endpoint
        conn = connectWS(transport_factory)
        confnodesroot.logger.write(_("WAMP connecting to URL : %s\n")%url)
        return conn

    def WampSessionProcMapper(funcname):
        def catcher_func(*args,**kwargs):
            if _WampSession is not None :
                try:
                    return threads.blockingCallFromThread(
                        reactor, _WampSession.call, funcname,
                        *args,**kwargs)
                except TransportLost, e:
                    confnodesroot.logger.write_error("Connection lost!\n")
                    confnodesroot._SetConnector(None)
                except Exception,e:
                    errmess = traceback.format_exc()
                    confnodesroot.logger.write_error(errmess+"\n")
                    print errmess
                    #confnodesroot._SetConnector(None)
            return PLCObjDefaults.get(funcname)
        return catcher_func

    class WampPLCObjectProxy(object):
        def __init__(self):
            if not reactor.running:
                def ThreadProc():
                    self.connection = RegisterWampClient()
                    reactor.run(installSignalHandlers=False)
                Thread(target=ThreadProc).start()
            else:
                self.connection = threads.blockingCallFromThread(
                    reactor, RegisterWampClient)
            if not _WampSessionEvent.wait(5):
                self.connection.stopConnecting()
                raise Exception, _("WAMP connection timeout")

        def __del__(self):
            self.connection.disconnect()
            #reactor.Stop()

        def __getattr__(self, attrName):
            member = self.__dict__.get(attrName, None)
            if member is None:
                member = WampSessionProcMapper(attrName)
                self.__dict__[attrName] = member
            return member

    # Try to get the proxy object
    try :
        return WampPLCObjectProxy()
    except Exception, msg:
        confnodesroot.logger.write_error(_("WAMP connection to '%s' failed.\n")%location)
        confnodesroot.logger.write_error(traceback.format_exc())
        return None