From c69a8e926d47723a51a0230ab4b6b6541b7c46f0 Mon Sep 17 00:00:00 2001
From: cnderrauber <zengjie9004@gmail.com>
Date: Mon, 13 Mar 2023 10:19:32 +0800
Subject: [PATCH] Send full muxing map

---
 go.mod                              |  2 +-
 go.sum                              |  2 --
 pkg/sfu/audioselection/forwarder.go | 25 +++++++++++++++----------
 3 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/go.mod b/go.mod
index dcf72b28e..cd7997a4c 100644
--- a/go.mod
+++ b/go.mod
@@ -103,4 +103,4 @@ require (
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )
 
-replace github.com/livekit/protocol => ../protocol
\ No newline at end of file
+replace github.com/livekit/protocol => ../protocol
diff --git a/go.sum b/go.sum
index 09d90a4fc..5706d00dd 100644
--- a/go.sum
+++ b/go.sum
@@ -232,8 +232,6 @@ github.com/livekit/mageutil v0.0.0-20230125210925-54e8a70427c1 h1:jm09419p0lqTkD
 github.com/livekit/mageutil v0.0.0-20230125210925-54e8a70427c1/go.mod h1:Rs3MhFwutWhGwmY1VQsygw28z5bWcnEYmS1OG9OxjOQ=
 github.com/livekit/mediatransportutil v0.0.0-20230130133657-96cfb115473a h1:5UkGQpskXp7HcBmyrCwWtO7ygDWbqtjN09Yva4l/nyE=
 github.com/livekit/mediatransportutil v0.0.0-20230130133657-96cfb115473a/go.mod h1:1Dlx20JPoIKGP45eo+yuj0HjeE25zmyeX/EWHiPCjFw=
-github.com/livekit/protocol v1.4.3-0.20230222030027-e946da680c7b h1:2toBhQKTJSqoizjUUOPapRX9prKpNcLxSuvhZ9NKeGI=
-github.com/livekit/protocol v1.4.3-0.20230222030027-e946da680c7b/go.mod h1:mVzmVesPCIgk2gg/jMr6PWtHu8dfRdhaAJ6okFs5nQw=
 github.com/livekit/psrpc v0.2.7 h1:j8ns7+t/7LJxTH/jnD9Ds7qn3VkNOV/qCUbt2nbirfU=
 github.com/livekit/psrpc v0.2.7/go.mod h1:2wtOo1F03vub2qIjx0rAPpVplg873670/LN08o/yopM=
 github.com/livekit/rtcscore-go v0.0.0-20220815072451-20ee10ae1995 h1:vOaY2qvfLihDyeZtnGGN1Law9wRrw8BMGCr1TygTvMw=
diff --git a/pkg/sfu/audioselection/forwarder.go b/pkg/sfu/audioselection/forwarder.go
index d567e94cb..7fb864742 100644
--- a/pkg/sfu/audioselection/forwarder.go
+++ b/pkg/sfu/audioselection/forwarder.go
@@ -59,6 +59,7 @@ type SelectionForwarder struct {
 	idleDowntracks []*sfu.DownTrack
 	downtracks     []*sfu.DownTrack
 	close          chan struct{}
+	sourceChanged  bool
 
 	onForwardMappingChanged func(muxInfo []*livekit.AudioTrackMuxInfo)
 }
@@ -111,6 +112,7 @@ func (f *SelectionForwarder) AddSource(participantID livekit.ParticipantID, trac
 	f.params.Logger.Debugw("adding source", "trackID", trackID)
 	f.lock.Lock()
 	f.sources = append(f.sources, &sourceInfo{participantID: participantID, trackID: trackID, receiver: source})
+	f.sourceChanged = true
 	f.lock.Unlock()
 }
 
@@ -126,6 +128,7 @@ func (f *SelectionForwarder) RemoveSource(trackID livekit.TrackID) {
 			break
 		}
 	}
+	f.sourceChanged = true
 	f.lock.Unlock()
 }
 
@@ -150,7 +153,7 @@ func (f *SelectionForwarder) process() {
 func (f *SelectionForwarder) updateForward() {
 	f.lock.Lock()
 	defer f.lock.Unlock()
-	if len(f.sources) == 0 {
+	if len(f.sources) == 0 && !f.sourceChanged {
 		return
 	}
 
@@ -186,19 +189,21 @@ func (f *SelectionForwarder) updateForward() {
 		}
 	}
 
-	if forwardChanged && f.onForwardMappingChanged != nil {
-		muxInfo := make([]*livekit.AudioTrackMuxInfo, 0, len(f.sources))
+	if (f.sourceChanged || forwardChanged) && f.onForwardMappingChanged != nil {
+		f.sourceChanged = false
+		muxInfos := make([]*livekit.AudioTrackMuxInfo, 0, len(f.sources))
 
 		for _, source := range f.sources {
-			if source.active && source.downtrack != nil {
-				muxInfo = append(muxInfo, &livekit.AudioTrackMuxInfo{
-					SdpTrackId:     source.downtrack.ID(),
-					ParticipantSid: string(source.participantID),
-					TrackSid:       string(source.trackID),
-				})
+			info := &livekit.AudioTrackMuxInfo{
+				ParticipantSid: string(source.participantID),
+				TrackSid:       string(source.trackID),
 			}
+			if source.downtrack != nil {
+				info.SdpTrackId = source.downtrack.ID()
+			}
+			muxInfos = append(muxInfos, info)
 		}
-		f.onForwardMappingChanged(muxInfo)
+		f.onForwardMappingChanged(muxInfos)
 	}
 }