--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/plugins/plugin_xep_0298.py	Mon Jul 29 03:31:13 2024 +0200
@@ -0,0 +1,143 @@
+#!/usr/bin/env python3
+
+
+# Libervia plugin to handle events
+# Copyright (C) 2009-2022 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 urllib.parse import quote, unquote
+from twisted.words.protocols.jabber import jid
+from twisted.words.xish import domish
+from libervia.backend.core.i18n import _
+from libervia.backend.core.constants import Const as C
+from libervia.backend.core.log import getLogger
+from wokkel import disco, iwokkel
+from zope.interface import implementer
+from twisted.words.protocols.jabber.xmlstream import XMPPHandler
+
+log = getLogger(__name__)
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: "Events",
+    C.PI_IMPORT_NAME: "XEP-0298",
+    C.PI_TYPE: "XEP",
+    C.PI_MODES: C.PLUG_MODE_BOTH,
+    C.PI_PROTOCOLS: [],
+    C.PI_DEPENDENCIES: [],
+    C.PI_MAIN: "XEP_0298",
+    C.PI_HANDLER: "yes",
+    C.PI_DESCRIPTION: _(
+        "Delivering Conference Information to Jingle Participants (Coin). This plugin "
+        "is used to associate metadata about uses an call states in multi-party calls."
+    ),
+}
+
+NS_COIN = "urn:xmpp:coin:1"
+NS_CONFERENCE_INFO = "urn:ietf:params:xml:ns:conference-info"
+
+
+class XEP_0298:
+    namespace = NS_COIN
+
+    def __init__(self, host):
+        log.info(f"plugin {PLUGIN_INFO[C.PI_NAME]!r} initialization")
+        self.host = host
+
+    def get_handler(self, client):
+        return CoinHandler(self)
+
+    def add_conference_info(
+        self, jingle_elt: domish.Element, is_focus: bool = False, **kwargs
+    ) -> domish.Element:
+        """Create and return a <conference_info> element
+
+        @param jingle_elt: parent element
+        @param kwargs: attributes of the element.
+        @return: created <conference-info> element.
+        """
+        conference_info_elt = jingle_elt.addElement(
+            (NS_CONFERENCE_INFO, "conference-info"),
+        )
+        if is_focus:
+            conference_info_elt["isfocus"] = C.BOOL_TRUE
+        conference_info_elt.attributes.update(kwargs)
+        return conference_info_elt
+
+    def add_user(
+        self, conference_info_elt: domish.Element, entity: jid.JID
+    ) -> domish.Element:
+        """Add an user to a cconference info element.
+
+        If the parent <users> doesn't exist, it will be created.
+        @param conference_info_elt: <conference-info> element where the <user> element
+        need to be added
+        @param entity: XMPP JID to use as entity.
+        @return: created <user> element.
+        """
+        try:
+            users_elt = next(conference_info_elt.elements(NS_CONFERENCE_INFO, "users"))
+        except StopIteration:
+            users_elt = conference_info_elt.addElement("users")
+
+        user_elt = users_elt.addElement("user")
+        user_elt["entity"] = f"xmpp:{quote(entity.userhost())}"
+        return user_elt
+
+    def parse(self, jingle_elt: domish.Element) -> dict:
+        """Parse a Jingle element and return a dictionary with conference info if present.
+
+        @param jingle_elt: Jingle element to parse.
+        @return: Dictionary with "info" key if conference info is found.
+        """
+        try:
+            conference_info_elt = next(
+                jingle_elt.elements((NS_CONFERENCE_INFO, "conference-info"))
+            )
+        except StopIteration:
+            return {}
+
+        users = []
+        try:
+            users_elt = next(conference_info_elt.elements(NS_CONFERENCE_INFO, "users"))
+            for user_elt in users_elt.elements(NS_CONFERENCE_INFO, "user"):
+                entity = user_elt.getAttribute("entity")
+                if entity.startswith("xmpp:"):
+                    try:
+                        entity = jid.JID(unquote(entity[5:]))
+                        users.append(entity)
+                    except Exception as e:
+                        log.warning(f"Failed to parse entity {entity!r}: {e}")
+                else:
+                    log.warning(f"Ignoring non-XMPP entity {entity!r}")
+        except StopIteration:
+            pass
+
+        return {"info": {"users": users}}
+
+
+@implementer(iwokkel.IDisco)
+class CoinHandler(XMPPHandler):
+
+    def __init__(self, plugin_parent):
+        self.plugin_parent = plugin_parent
+
+    def getDiscoInfo(self, requestor, target, nodeIdentifier=""):
+        return [
+            disco.DiscoFeature(NS_COIN),
+        ]
+
+    def getDiscoItems(self, requestor, target, nodeIdentifier=""):
+        return []