From f112e26d251fb80657c9af43f300b04bc8e612f8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Calvi=C3=B1o=20S=C3=A1nchez?= <danxuliu@gmail.com>
Date: Mon, 23 Dec 2024 18:40:06 +0100
Subject: [PATCH] Fix SDP constraints used by PeerConnectionWrapper
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The SDP constraints for publisher connections when the MCU is used were
set for all connections. Those constraints set "OfferToReceiveAudio" and
"OfferToReceiveVideo" to false, which disables receiving audio and video
when the local participant is the one sending the offer. Therefore,
audio and video was not received when the MCU was not used and the local
participant was the one initiating the connection.

The "OfferToReceiveXXX" configurations have no effect when set on an
answer (and thus are not even set, an empty MediaConstraints is used in
that case). However, when "OfferToReceiveVideo = false" is set the video
transceiver is explicitly stopped (which is used to avoid receiving
video when joining a call with audio only). Therefore, as
"OfferToReceiveVideo = false" was always set, video was never received
in subscriber connections when the MCU is used, or connections initiated
by the other peer when the MCU is not used.

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>
---
 .../main/java/com/nextcloud/talk/activities/CallActivity.kt | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt b/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt
index ac5259bdd..84a746225 100644
--- a/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt
+++ b/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt
@@ -2350,18 +2350,22 @@ class CallActivity : CallBaseActivity() {
         sessionId: String?,
         type: String
     ): PeerConnectionWrapper {
+        val tempSdpConstraints: MediaConstraints?
         val tempIsMCUPublisher: Boolean
         val tempHasMCU: Boolean
         val tempLocalStream: MediaStream?
         if (hasMCU && publisher) {
+            tempSdpConstraints = sdpConstraintsForMCUPublisher
             tempIsMCUPublisher = true
             tempHasMCU = true
             tempLocalStream = localStream
         } else if (hasMCU) {
+            tempSdpConstraints = sdpConstraints
             tempIsMCUPublisher = false
             tempHasMCU = true
             tempLocalStream = null
         } else {
+            tempSdpConstraints = sdpConstraints
             tempIsMCUPublisher = false
             tempHasMCU = false
             tempLocalStream = if ("screen" != type) {
@@ -2374,7 +2378,7 @@ class CallActivity : CallBaseActivity() {
         return PeerConnectionWrapper(
             peerConnectionFactory,
             iceServers,
-            sdpConstraintsForMCUPublisher,
+            tempSdpConstraints,
             sessionId,
             callSession,
             tempLocalStream,