#!/usr/bin/env python3


# SAT plugin for Jingle (XEP-0261)
# Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from libervia.backend.core.i18n import _
from libervia.backend.core.constants import Const as C
from libervia.backend.core.log import getLogger
from libervia.backend.plugins.plugin_xep_0166.models import BaseTransportHandler

log = getLogger(__name__)
from wokkel import disco, iwokkel
from zope.interface import implementer
from twisted.words.xish import domish
import uuid

try:
    from twisted.words.protocols.xmlstream import XMPPHandler
except ImportError:
    from wokkel.subprotocols import XMPPHandler


NS_JINGLE_IBB = "urn:xmpp:jingle:transports:ibb:1"

PLUGIN_INFO = {
    C.PI_NAME: "Jingle In-Band Bytestreams",
    C.PI_IMPORT_NAME: "XEP-0261",
    C.PI_TYPE: "XEP",
    C.PI_MODES: C.PLUG_MODE_BOTH,
    C.PI_PROTOCOLS: ["XEP-0261"],
    C.PI_DEPENDENCIES: ["XEP-0166", "XEP-0047"],
    C.PI_MAIN: "XEP_0261",
    C.PI_HANDLER: "yes",
    C.PI_DESCRIPTION: _("""Implementation of Jingle In-Band Bytestreams"""),
}


class XEP_0261(BaseTransportHandler):
    NAMESPACE = NS_JINGLE_IBB  # used by XEP-0260 plugin for transport-replace

    def __init__(self, host):
        log.info(_("plugin Jingle In-Band Bytestreams"))
        self.host = host
        self._j = host.plugins["XEP-0166"]  # shortcut to access jingle
        self._ibb = host.plugins["XEP-0047"]  # and in-band bytestream
        self._j.register_transport(
            NS_JINGLE_IBB, self._j.TRANSPORT_STREAMING, self, -10000
        )  # must be the lowest priority

    def get_handler(self, client):
        return XEP_0261_handler()

    def jingle_session_init(self, client, session, content_name):
        transport_elt = domish.Element((NS_JINGLE_IBB, "transport"))
        content_data = session["contents"][content_name]
        transport_data = content_data["transport_data"]
        transport_data["block_size"] = self._ibb.BLOCK_SIZE
        transport_elt["block-size"] = str(transport_data["block_size"])
        transport_elt["sid"] = transport_data["sid"] = str(uuid.uuid4())
        return transport_elt

    def jingle_handler(self, client, action, session, content_name, transport_elt):
        content_data = session["contents"][content_name]
        transport_data = content_data["transport_data"]
        if action in (
            self._j.A_SESSION_ACCEPT,
            self._j.A_ACCEPTED_ACK,
            self._j.A_TRANSPORT_ACCEPT,
        ):
            pass
        elif action in (self._j.A_SESSION_INITIATE, self._j.A_TRANSPORT_REPLACE):
            transport_data["sid"] = transport_elt["sid"]
        elif action in (self._j.A_START, self._j.A_PREPARE_RESPONDER):
            local_jid = session["local_jid"]
            peer_jid = session["peer_jid"]
            sid = transport_data["sid"]
            stream_object = content_data["stream_object"]
            if action == self._j.A_START:
                block_size = transport_data["block_size"]
                d = self._ibb.start_stream(
                    client, stream_object, local_jid, peer_jid, sid, block_size
                )
                d.chainDeferred(content_data["finished_d"])
            else:
                d = self._ibb.create_session(
                    client, stream_object, local_jid, peer_jid, sid)
                d.chainDeferred(content_data["finished_d"])
        else:
            log.warning("FIXME: unmanaged action {}".format(action))
        return transport_elt


@implementer(iwokkel.IDisco)
class XEP_0261_handler(XMPPHandler):

    def getDiscoInfo(self, requestor, target, nodeIdentifier=""):
        return [disco.DiscoFeature(NS_JINGLE_IBB)]

    def getDiscoItems(self, requestor, target, nodeIdentifier=""):
        return []