plugin XEP-0167, XEP-0353: handle ringing:

- add a `jingle_preflight_info` method in the Jingle Application model to handle this kind
  of information
- XEP-0353 is calling `jingle_preflight_info` when a `ringing` message is received
- XEP-0167 use this information to send a `ringing` info to frontends

libervia/backend/plugins/plugin_xep_0166/models.py

@@ -43,6 +43,20 @@ class BaseApplicationHandler(abc.ABC):
         """
         pass
 
+    @abc.abstractmethod
+    async def jingle_preflight_info(
+        self,
+        client: SatXMPPEntity,
+        session: dict,
+        info_type: str,
+        info_data: dict|None = None
+    ) -> None:
+        """Called when we have new information during preflight
+
+        Notably used by XEP-0353 to signal ringing
+        """
+        pass
+
     @abc.abstractmethod
     async def jingle_preflight_cancel(
         self,

libervia/backend/plugins/plugin_xep_0167/__init__.py

@@ -387,6 +387,24 @@ class XEP_0167(BaseApplicationHandler):
         if not accepted:
             raise exceptions.CancelError("User declined the incoming call.")
 
+    async def jingle_preflight_info(
+        self,
+        client: SatXMPPEntity,
+        session: dict,
+        info_type: str,
+        info_data: dict|None = None
+    ) -> None:
+        if info_type == "ringing":
+            if not session.get("ringing", False):
+                self.host.bridge.call_info(
+                    session["id"], "ringing", "", client.profile
+                )
+                # we indicate that the ringing has started, to avoid sending several times
+                # the signal
+                session["ringing"] = True
+        else:
+            log.warning(f"Unknown preflight info type: {info_type!r}")
+
     async def jingle_preflight_cancel(
         self,
         client: SatXMPPEntity,

libervia/backend/plugins/plugin_xep_0234.py

@@ -464,6 +464,15 @@ class XEP_0234(BaseApplicationHandler):
             session["file_accepted"] = True
         return accepted
 
+    async def jingle_preflight_info(
+        self,
+        client: SatXMPPEntity,
+        session: dict,
+        info_type: str,
+        info_data: dict|None = None
+    ) -> None:
+        pass
+
     async def jingle_preflight_cancel(
         self,
         client: SatXMPPEntity,

libervia/backend/plugins/plugin_xep_0353.py

@@ -29,7 +29,6 @@ from libervia.backend.core.constants import Const as C
 from libervia.backend.core.core_types import SatXMPPEntity
 from libervia.backend.core.i18n import D_, _
 from libervia.backend.core.log import getLogger
-from libervia.backend.tools import xml_tools
 
 log = getLogger(__name__)
 
@@ -215,6 +214,8 @@ class XEP_0353:
                     return self._handle_accept(client, message_elt, elt)
                 elif elt.name == "reject":
                     return self._handle_reject(client, message_elt, elt)
+                elif elt.name == "ringing":
+                    return await self._handle_ringing(client, message_elt, elt)
                 else:
                     log.warning(f"invalid element: {elt.toXml}")
                     return True
@@ -367,6 +368,20 @@ class XEP_0353:
         response_d.errback(RejectException(reason, text))
         return False
 
+    async def _handle_ringing(self, client, message_elt, ringing_elt):
+        session_id = ringing_elt["id"]
+        try:
+            session = self._j.get_session(client, session_id)
+        except exceptions.NotFound:
+            log.warning(f"Session {session_id!r} unknown, ignoring ringing.")
+            return False
+        for __, content_data in session["contents"].items():
+            await content_data["application"].handler.jingle_preflight_info(
+                client, session, "ringing", None
+            )
+
+        return False
+
 
 @implementer(iwokkel.IDisco)
 class Handler(xmlstream.XMPPHandler):