From df0ab77791658977a6e244655a8c1bd60d1be014 Mon Sep 17 00:00:00 2001
From: Alexey Khit <alexey.khit@gmail.com>
Date: Wed, 1 Mar 2023 17:20:33 +0300
Subject: [PATCH] Update receiving remote candidate info for webrtc

---
 pkg/webrtc/conn.go     | 48 +++++++++++-------------------------------
 pkg/webrtc/consumer.go |  2 +-
 2 files changed, 13 insertions(+), 37 deletions(-)

diff --git a/pkg/webrtc/conn.go b/pkg/webrtc/conn.go
index db4ee888..78e6a082 100644
--- a/pkg/webrtc/conn.go
+++ b/pkg/webrtc/conn.go
@@ -20,6 +20,7 @@ type Conn struct {
 	send    int
 
 	offer  string
+	remote string
 	closed core.Waiter
 }
 
@@ -34,6 +35,17 @@ func NewConn(pc *webrtc.PeerConnection) *Conn {
 		c.Fire(channel)
 	})
 
+	pc.OnICEConnectionStateChange(func(state webrtc.ICEConnectionState) {
+		if state != webrtc.ICEConnectionStateChecking {
+			return
+		}
+		pc.SCTP().Transport().ICETransport().OnSelectedCandidatePairChange(
+			func(pair *webrtc.ICECandidatePair) {
+				c.remote = pair.Remote.String()
+			},
+		)
+	})
+
 	pc.OnTrack(func(remote *webrtc.TrackRemote, _ *webrtc.RTPReceiver) {
 		track := c.getTrack(remote)
 		if track == nil {
@@ -110,39 +122,3 @@ func (c *Conn) getTrack(remote *webrtc.TrackRemote) *streamer.Track {
 
 	return nil
 }
-
-func (c *Conn) remote() string {
-	if c.pc == nil {
-		return ""
-	}
-
-	for _, trans := range c.pc.GetTransceivers() {
-		if trans == nil {
-			continue
-		}
-
-		receiver := trans.Receiver()
-		if receiver == nil {
-			continue
-		}
-
-		transport := receiver.Transport()
-		if transport == nil {
-			continue
-		}
-
-		iceTransport := transport.ICETransport()
-		if iceTransport == nil {
-			continue
-		}
-
-		pair, _ := iceTransport.GetSelectedCandidatePair()
-		if pair == nil || pair.Remote == nil {
-			continue
-		}
-
-		return pair.Remote.String()
-	}
-
-	return ""
-}
diff --git a/pkg/webrtc/consumer.go b/pkg/webrtc/consumer.go
index 828a03f1..9e73bf50 100644
--- a/pkg/webrtc/consumer.go
+++ b/pkg/webrtc/consumer.go
@@ -114,7 +114,7 @@ func (c *Conn) AddTrack(media *streamer.Media, track *streamer.Track) *streamer.
 func (c *Conn) MarshalJSON() ([]byte, error) {
 	info := &streamer.Info{
 		Type:       "WebRTC",
-		RemoteAddr: c.remote(),
+		RemoteAddr: c.remote,
 		UserAgent:  c.UserAgent,
 		Medias:     c.medias,
 		Tracks:     c.tracks,