scenic

#!/usr/bin/env python

# -*- coding: utf-8 -*-

# 

# Scenic

# Copyright (C) 2008 Société des arts technologiques (SAT)

# http://www.sat.qc.ca

# All rights reserved.

#

# This file 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 of the License, or

# (at your option) any later version.

#

# Scenic 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 Scenic. If not, see <http://www.gnu.org/licenses/>.

"""

Main application 

"""

import os

import gtk # for dialog responses. TODO: remove

from twisted.internet import defer

from twisted.internet import error

from twisted.internet import reactor

from scenic import communication

from scenic import saving

from scenic import process # just for constants

from scenic.streamer import StreamerManager

from scenic import dialogs

from scenic import ports

from scenic import gui

from scenic.gui import _ # gettext

class Config(saving.ConfigStateSaving):

    """

    Class attributes are default.

    """

    # Default values

    negotiation_port = 17446 # receiving TCP (SIC) messages on it.

    smtpserver = "smtp.sat.qc.ca"

    email_info = "scenic@sat.qc.ca"

    audio_source = "jackaudiosrc"

    audio_sink = "jackaudiosink"

    audio_codec = "raw"

    audio_channels = 8

    video_source = "v4l2src"

    video_device = "/dev/video0"

    video_sink = "xvimagesink"

    video_codec = "mpeg4"

    video_display = ":0.0"

    video_bitrate = "3000000"

    video_width = 640

    video_height = 480

    confirm_quit = False

    theme = "Darklooks"

    def __init__(self):

        config_file = 'scenic.cfg'

        if os.path.isfile('/etc/' + config_file):

            config_dir = '/etc'

        else:

            config_dir = os.environ['HOME'] + '/.scenic'

        config_file_path = os.path.join(config_dir, config_file)

        saving.ConfigStateSaving.__init__(self, config_file_path)

class Application(object):

    def __init__(self, kiosk_mode=False, fullscreen=False):

        self.config = Config()

        self.send_video_port = None

        self.recv_video_port = None

        self.send_audio_port = None

        self.recv_audio_port = None

        self.ports_allocator = ports.PortsAllocator()

        self.address_book = saving.AddressBook()

        self.streamer_manager = StreamerManager(self)

        self._has_session = False

        self.streamer_manager.state_changed_signal.connect(self.on_streamer_state_changed) # XXX

        print("Starting SIC server on port %s" % (self.config.negotiation_port)) 

        self.server = communication.Server(self, self.config.negotiation_port) # XXX

        self.client = None 

        self.got_bye = False 

        # starting the GUI:

        self.gui = gui.Gui(self, kiosk_mode=kiosk_mode, fullscreen=fullscreen)

        reactor.addSystemEventTrigger("before", "shutdown", self.before_shutdown)

        try:

            self.server.start_listening()

        except error.CannotListenError, e:

            print("Cannot start SIC server.")

            print(str(e))

            raise

    def before_shutdown(self):

        """

        Last things done before quitting.

        """

        print("The application is shutting down.")

        # TODO: stop streamers

        if self.client is not None:

            if not self.got_bye:

                self.send_bye()

                self.stop_streamers()

            self.disconnect_client()

        print('stopping server')

        self.server.close()

    # ------------------------- session occuring -------------

    def has_session(self):

        """

        @rettype: bool

        """

        return self._has_session

    # -------------------- streamer ports -----------------

    def allocate_ports(self):

        # TODO: start_session

        self.recv_video_port = self.ports_allocator.allocate()

        self.recv_audio_port = self.ports_allocator.allocate()

    def free_ports(self):

        # TODO: stop_session

        for port in [self.recv_video_port, self.recv_audio_port]:

            try:

                self.ports_allocator.free(port)

            except ports.PortsAllocatorError, e:

                print(e)

    def save_configuration(self):

        """

        Saves the configuration to a file.

        Reads the widget value prior to do it.

        """

        self.gui._gather_configuration() # need to get the value of the configuration widgets.

        self.config.save()

        self.address_book.save() # addressbook values are already stored.

    # --------------------------- network receives ------------

    def handle_invite(self, message, addr):

        self.got_bye = False

        send_to_port = message["please_send_to_port"]

        def _on_contact_request_dialog_response(response):

            """

            User is accetping or declining an offer.

            @param result: Answer to the dialog.

            """

            if response == gtk.RESPONSE_OK:

                if self.client is not None:

                    self.send_accept(message, addr)

                else:

                    print("Error: connection lost, so we could not accept.")# FIXME

            elif response == gtk.RESPONSE_CANCEL or gtk.RESPONSE_DELETE_EVENT:

                self.send_refuse_and_disconnect() 

            else:

                pass

            return True

        if self.streamer_manager.is_busy():

            print("Got invitation, but we are busy.")

            communication.connect_send_and_disconnect(addr, send_to_port, {'msg':'REFUSE', 'sid':0}) #FIXME: where do we get the port number from?

        else:

            self.client = communication.Client(self, send_to_port)

            self.client.connect(addr)

            # TODO: if a contact in the addressbook has this address, displays it!

            text = _("<b><big>%s is inviting you.</big></b>\n\nDo you accept the connection?" % addr)

            self.gui.show_invited_dialog(text, _on_contact_request_dialog_response)

    def handle_cancel(self):

        if self.client is not None:

            self.client.disconnect()

            self.client = None

        self.gui.invited_dialog.hide()

        dialogs.ErrorDialog.create("Remote peer cancelled invitation.", parent=self.gui.main_window)

    def handle_accept(self, message, addr):

        self.gui._unschedule_offerer_invite_timeout()

        # FIXME: this doesn't make sense here

        self.got_bye = False

        # TODO: Use session to contain settings and ports

        if self.client is not None:

            self.gui.hide_calling_dialog("accept")

            self.send_video_port = message["videoport"]

            self.send_audio_port = message["audioport"]

            if self.streamer_manager.is_busy():

                dialogs.ErrorDialog.create("A streaming session is already in progress.", parent=self.gui.main_window)

            else:

                print("Got ACCEPT. Starting streamers as initiator.")

                self.start_streamers(addr)

                self.send_ack()

        else:

            print("Error ! Connection lost.") # FIXME

    def handle_refuse(self):

        self.gui._unschedule_offerer_invite_timeout()

        self.free_ports()

        self.gui.hide_calling_dialog("refuse")

    def handle_ack(self, addr):

        print("Got ACK. Starting streamers as answerer.")

        self.start_streamers(addr)

    def handle_bye(self):

        self.got_bye = True

        self.stop_streamers()

        if self.client is not None:

            print('disconnecting client and sending BYE')

            self.client.send({"msg":"OK", "sid":0})

            self.disconnect_client()

    def handle_ok(self):

        print("received ok. Everything has an end.")

        print('disconnecting client')

        self.disconnect_client()

    def on_server_receive_command(self, message, addr):

        # XXX

        msg = message["msg"]

        print("Got %s from %s" % (msg, addr))

        if msg == "INVITE":

            self.handle_invite(message, addr)

        elif msg == "CANCEL":

            self.handle_cancel()

        elif msg == "ACCEPT":

            self.handle_accept(message, addr)

        elif msg == "REFUSE":

            self.handle_refuse()

        elif msg == "ACK":

            self.handle_ack(addr)

        elif msg == "BYE":

            self.handle_bye()

        elif msg == "OK":

            self.handle_ok()

        else:

            print ('WARNING: Unexpected message %s' % (msg))

    # -------------------------- actions on streamer manager --------

    def start_streamers(self, addr):

        self._has_session = True

        self.streamer_manager.start(addr, self.config)

    def stop_streamers(self):

        self.streamer_manager.stop()

    def on_streamers_stopped(self, addr):

        """

        We call this when all streamers are stopped.

        """

        print("on_streamers_stopped got called")

        self._has_session = False

        self.free_ports()

    # ---------------------- sending messages -----------

    def disconnect_client(self):

        """

        Disconnects the SIC sender.

        @rettype: L{Deferred}

        """

        def _cb(result, d1):

            self.client = None

            d1.callback(True)

        def _cl(d1):

            if self.client is not None:

                d2 = self.client.disconnect()

                d2.addCallback(_cb, d1)

            else:

                d1.callback(True)

        if self.client is not None:

            d = defer.Deferred()

            reactor.callLater(0, _cl, d)

            return d

        else: 

            return defer.succeed(True)

    def send_invite(self):

        self.allocate_ports()

        if self.streamer_manager.is_busy():

            dialogs.ErrorDialog.create("Impossible to invite a contact to start streaming. A streaming session is already in progress.", parent=self.gui.main_window)

        else:

            # UPDATE when initiating session

            self.gui._gather_configuration()

        msg = {

            "msg":"INVITE",

            "sid":0, 

            "videoport": self.recv_video_port,

            "audioport": self.recv_audio_port,

            "please_send_to_port": self.config.negotiation_port

            }

        port = self.config.negotiation_port

        ip = self.address_book.selected_contact["address"]

        def _on_connected(proto):

            self.gui._schedule_offerer_invite_timeout()

            self.client.send(msg)

            return proto

        def _on_error(reason):

            print ("error trying to connect to %s:%s : %s" % (ip, port, reason))

            self.gui.calling_dialog.hide()

            self.client = None

            return None

        print ("sending %s to %s:%s" % (msg, ip, port))

        self.client = communication.Client(self, port)

        deferred = self.client.connect(ip)

        deferred.addCallback(_on_connected).addErrback(_on_error)

        self.gui.calling_dialog.show()

        # window will be hidden when we receive ACCEPT or REFUSE

    def send_accept(self, message, addr):

        # UPDATE config once we accept the invitie

        self.gui._gather_configuration()

        self.allocate_ports()

        self.client.send({"msg":"ACCEPT", "videoport":self.recv_video_port, "audioport":self.recv_audio_port, "sid":0})

        # TODO: Use session to contain settings and ports

        self.send_video_port = message["videoport"]

        self.send_audio_port = message["audioport"]

    def send_ack(self):

        self.client.send({"msg":"ACK", "sid":0})

    def send_bye(self):

        """

        Sends BYE

        BYE stops the streaming on the remote host.

        """

        if self.client is not None:

            self.client.send({"msg":"BYE", "sid":0})

    def send_cancel_and_disconnect(self):

        """

        Sends CANCEL

        CANCEL cancels the invite on the remote host.

        """

        if self.client is not None:

            self.client.send({"msg":"CANCEL", "sid":0})

            self.client.disconnect()

            self.client = None

        else:

            print('Warning: Trying to send CANCEL even though client is None')

    def send_refuse_and_disconnect(self):

        """

        Sends REFUSE 

        REFUSE tells the offerer we can't have a session.

        """

        if self.client is not None:

            self.client.send({"msg":"REFUSE", "sid":0})

            self.client.disconnect()

            self.client = None

        else:

            print('Warning: Trying to send REFUSE even though client is None')

    # ------------------- streaming events handlers ----------------

    def on_streamer_state_changed(self, streamer, new_state):

        """

        Slot for scenic.streamer.StreamerManager.state_changed_signal

        """

        if new_state in [process.STATE_STOPPED]:

            if not self.got_bye:

                """ got_bye means our peer sent us a BYE, so we shouldn't send one back """

                print("Local StreamerManager stopped. Sending BYE")

                self.send_bye()

    def on_client_socket_error(self, client, err, msg):

        # XXX

        self.gui.hide_calling_dialog(msg)

        text = _("%s: %s") % (str(err), str(msg))

        self.gui.show_error_dialog(text)