--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/plugins/plugin_xep_0293.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,312 @@
+#!/usr/bin/env python3
+
+# Libervia plugin
+# Copyright (C) 2009-2023 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 typing import List
+
+from twisted.words.protocols.jabber.xmlstream import XMPPHandler
+from twisted.words.xish import domish
+from wokkel import disco, iwokkel
+from zope.interface import implementer
+
+from libervia.backend.core.constants import Const as C
+from libervia.backend.core.i18n import _
+from libervia.backend.core.log import getLogger
+
+log = getLogger(__name__)
+
+NS_JINGLE_RTP_RTCP_FB = "urn:xmpp:jingle:apps:rtp:rtcp-fb:0"
+
+PLUGIN_INFO = {
+    C.PI_NAME: "Jingle RTP Feedback Negotiation",
+    C.PI_IMPORT_NAME: "XEP-0293",
+    C.PI_TYPE: "XEP",
+    C.PI_MODES: C.PLUG_MODE_BOTH,
+    C.PI_PROTOCOLS: ["XEP-0293"],
+    C.PI_DEPENDENCIES: ["XEP-0092", "XEP-0166", "XEP-0167"],
+    C.PI_RECOMMENDATIONS: [],
+    C.PI_MAIN: "XEP_0293",
+    C.PI_HANDLER: "yes",
+    C.PI_DESCRIPTION: _("""Jingle RTP Feedback Negotiation"""),
+}
+
+RTCP_FB_KEY = "rtcp-fb"
+
+
+class XEP_0293:
+    def __init__(self, host):
+        log.info(f"plugin {PLUGIN_INFO[C.PI_NAME]!r} initialization")
+        host.trigger.add("XEP-0167_parse_sdp_a", self._parse_sdp_a_trigger)
+        host.trigger.add(
+            "XEP-0167_generate_sdp_content", self._generate_sdp_content_trigger
+        )
+        host.trigger.add("XEP-0167_parse_description", self._parse_description_trigger)
+        host.trigger.add(
+            "XEP-0167_parse_description_payload_type",
+            self._parse_description_payload_type_trigger,
+        )
+        host.trigger.add("XEP-0167_build_description", self._build_description_trigger)
+        host.trigger.add(
+            "XEP-0167_build_description_payload_type",
+            self._build_description_payload_type_trigger,
+        )
+
+    def get_handler(self, client):
+        return XEP_0293_handler()
+
+    ## SDP
+
+    def _parse_sdp_a_trigger(
+        self,
+        attribute: str,
+        parts: List[str],
+        call_data: dict,
+        metadata: dict,
+        media_type: str,
+        application_data: dict,
+        transport_data: dict,
+    ) -> None:
+        """Parse "rtcp-fb" and "rtcp-fb-trr-int" attributes
+
+        @param attribute: The attribute being parsed.
+        @param parts: The list of parts in the attribute.
+        @param call_data: The call data dict.
+        @param metadata: The metadata dict.
+        @param media_type: The media type (e.g., audio, video).
+        @param application_data: The application data dict.
+        @param transport_data: The transport data dict.
+        @param payload_map: The payload map dict.
+        """
+        if attribute == "rtcp-fb":
+            pt_id = parts[0]
+            feedback_type = parts[1]
+
+            feedback_subtype = None
+            parameters = {}
+
+            # Check if there are extra parameters
+            if len(parts) > 2:
+                feedback_subtype = parts[2]
+
+            if len(parts) > 3:
+                for parameter in parts[3:]:
+                    name, _, value = parameter.partition("=")
+                    parameters[name] = value or None
+
+            # Check if this feedback is linked to a payload type
+            if pt_id == "*":
+                # Not linked to a payload type, add to application data
+                application_data.setdefault(RTCP_FB_KEY, []).append(
+                    (feedback_type, feedback_subtype, parameters)
+                )
+            else:
+                payload_types = application_data.get("payload_types", {})
+                try:
+                    payload_type = payload_types[int(pt_id)]
+                except KeyError:
+                    log.warning(
+                        f"Got reference to unknown payload type {pt_id}: "
+                        f"{' '.join(parts)}"
+                    )
+                else:
+                    # Linked to a payload type, add to payload data
+                    payload_type.setdefault(RTCP_FB_KEY, []).append(
+                        (feedback_type, feedback_subtype, parameters)
+                    )
+
+        elif attribute == "rtcp-fb-trr-int":
+            pt_id = parts[0]  # Payload type ID
+            interval = int(parts[1])
+
+            # Check if this interval is linked to a payload type
+            if pt_id == "*":
+                # Not linked to a payload type, add to application data
+                application_data["rtcp-fb-trr-int"] = interval
+            else:
+                payload_types = application_data.get("payload_types", {})
+                try:
+                    payload_type = payload_types[int(pt_id)]
+                except KeyError:
+                    log.warning(
+                        f"Got reference to unknown payload type {pt_id}: "
+                        f"{' '.join(parts)}"
+                    )
+                else:
+                    # Linked to a payload type, add to payload data
+                    payload_type["rtcp-fb-trr-int"] = interval
+
+    def _generate_rtcp_fb_lines(
+        self, data: dict, pt_id: str, sdp_lines: List[str]
+    ) -> None:
+        for type_, subtype, parameters in data.get(RTCP_FB_KEY, []):
+            parameters_strs = [
+                f"{k}={v}" if v is not None else k for k, v in parameters.items()
+            ]
+            parameters_str = " ".join(parameters_strs)
+
+            sdp_line = f"a=rtcp-fb:{pt_id} {type_}"
+            if subtype:
+                sdp_line += f" {subtype}"
+            if parameters_str:
+                sdp_line += f" {parameters_str}"
+            sdp_lines.append(sdp_line)
+
+    def _generate_rtcp_fb_trr_int_lines(
+        self, data: dict, pt_id: str, sdp_lines: List[str]
+    ) -> None:
+        if "rtcp-fb-trr-int" not in data:
+            return
+        sdp_lines.append(f"a=rtcp-fb:{pt_id} trr-int {data['rtcp-fb-trr-int']}")
+
+    def _generate_sdp_content_trigger(
+        self,
+        session: dict,
+        local: bool,
+        content_name: str,
+        content_data: dict,
+        sdp_lines: List[str],
+        application_data: dict,
+        app_data_key: str,
+        media_data: dict,
+        media: str,
+    ) -> None:
+        """Generate SDP attributes "rtcp-fb" and "rtcp-fb-trr-int" from application data.
+
+        @param session: The session data.
+        @param local: Whether this is local or remote content.
+        @param content_name: The name of the content.
+        @param content_data: The data of the content.
+        @param sdp_lines: The list of SDP lines to append to.
+        @param application_data: The application data dict.
+        @param app_data_key: The key for the application data.
+        @param media_data: The media data dict.
+        @param media: The media type (e.g., audio, video).
+        """
+        # Generate lines for application data
+        self._generate_rtcp_fb_lines(application_data, "*", sdp_lines)
+        self._generate_rtcp_fb_trr_int_lines(application_data, "*", sdp_lines)
+
+        # Generate lines for each payload type
+        for pt_id, payload_data in media_data.get("payload_types", {}).items():
+            self._generate_rtcp_fb_lines(payload_data, pt_id, sdp_lines)
+            self._generate_rtcp_fb_trr_int_lines(payload_data, pt_id, sdp_lines)
+
+    ## XML
+
+    def _parse_rtcp_fb_elements(self, parent_elt: domish.Element, data: dict) -> None:
+        """Parse the <rtcp-fb> and <rtcp-fb-trr-int> elements.
+
+        @param parent_elt: The parent domish.Element.
+        @param data: The data dict to populate.
+        """
+        for rtcp_fb_elt in parent_elt.elements(NS_JINGLE_RTP_RTCP_FB, "rtcp-fb"):
+            try:
+                type_ = rtcp_fb_elt["type"]
+                subtype = rtcp_fb_elt.getAttribute("subtype")
+
+                parameters = {}
+                for parameter_elt in rtcp_fb_elt.elements(
+                    NS_JINGLE_RTP_RTCP_FB, "parameter"
+                ):
+                    parameters[parameter_elt["name"]] = parameter_elt.getAttribute(
+                        "value"
+                    )
+
+                data.setdefault(RTCP_FB_KEY, []).append((type_, subtype, parameters))
+            except (KeyError, ValueError) as e:
+                log.warning(f"Error while parsing <rtcp-fb>: {e}\n{rtcp_fb_elt.toXml()}")
+
+        for rtcp_fb_trr_int_elt in parent_elt.elements(
+            NS_JINGLE_RTP_RTCP_FB, "rtcp-fb-trr-int"
+        ):
+            try:
+                interval_value = int(rtcp_fb_trr_int_elt["value"])
+                data.setdefault("rtcp_fb_trr_int", []).append(interval_value)
+            except (KeyError, ValueError) as e:
+                log.warning(
+                    f"Error while parsing <rtcp-fb-trr-int>: {e}\n"
+                    f"{rtcp_fb_trr_int_elt.toXml()}"
+                )
+
+    def _parse_description_trigger(
+        self, desc_elt: domish.Element, media_data: dict
+    ) -> None:
+        """Parse the <rtcp-fb> and <rtcp-fb-trr-int> elements from a description.
+
+        @param desc_elt: The <description> domish.Element.
+        @param media_data: The media data dict to populate.
+        """
+        self._parse_rtcp_fb_elements(desc_elt, media_data)
+
+    def _parse_description_payload_type_trigger(
+        self,
+        desc_elt: domish.Element,
+        media_data: dict,
+        payload_type_elt: domish.Element,
+        payload_type_data: dict,
+    ) -> None:
+        """Parse the <rtcp-fb> and <rtcp-fb-trr-int> elements from a payload type.
+
+        @param desc_elt: The <description> domish.Element.
+        @param media_data: The media data dict.
+        @param payload_type_elt: The <payload-type> domish.Element.
+        @param payload_type_data: The payload type data dict to populate.
+        """
+        self._parse_rtcp_fb_elements(payload_type_elt, payload_type_data)
+
+    def build_rtcp_fb_elements(self, parent_elt: domish.Element, data: dict) -> None:
+        """Helper method to build the <rtcp-fb> and <rtcp-fb-trr-int> elements"""
+        for type_, subtype, parameters in data.get(RTCP_FB_KEY, []):
+            rtcp_fb_elt = parent_elt.addElement((NS_JINGLE_RTP_RTCP_FB, "rtcp-fb"))
+            rtcp_fb_elt["type"] = type_
+            if subtype:
+                rtcp_fb_elt["subtype"] = subtype
+            for name, value in parameters.items():
+                param_elt = rtcp_fb_elt.addElement(name)
+                if value is not None:
+                    param_elt.addContent(str(value))
+
+        if "rtcp-fb-trr-int" in data:
+            rtcp_fb_trr_int_elt = parent_elt.addElement(
+                (NS_JINGLE_RTP_RTCP_FB, "rtcp-fb-trr-int")
+            )
+            rtcp_fb_trr_int_elt["value"] = str(data["rtcp-fb-trr-int"])
+
+    def _build_description_payload_type_trigger(
+        self,
+        desc_elt: domish.Element,
+        media_data: dict,
+        payload_type: dict,
+        payload_type_elt: domish.Element,
+    ) -> None:
+        """Build the <rtcp-fb> and <rtcp-fb-trr-int> elements for a payload type"""
+        self.build_rtcp_fb_elements(payload_type_elt, payload_type)
+
+    def _build_description_trigger(
+        self, desc_elt: domish.Element, media_data: dict, session: dict
+    ) -> None:
+        """Build the <rtcp-fb> and <rtcp-fb-trr-int> elements for a media description"""
+        self.build_rtcp_fb_elements(desc_elt, media_data)
+
+
+@implementer(iwokkel.IDisco)
+class XEP_0293_handler(XMPPHandler):
+    def getDiscoInfo(self, requestor, target, nodeIdentifier=""):
+        return [disco.DiscoFeature(NS_JINGLE_RTP_RTCP_FB)]
+
+    def getDiscoItems(self, requestor, target, nodeIdentifier=""):
+        return []