feat(salutejazz): send track:add before publisher offer

internal/engine/salutejazz/salutejazz.go

@@ -199,6 +199,8 @@ func (s *Session) createPeerConnections(api *webrtc.API, config webrtc.Configura
 		if track.Kind() != webrtc.RTPCodecTypeVideo {
 			return
 		}
+		logger.Infof("[salutejazz] remote video track: codec=%s stream=%s track=%s",
+			track.Codec().MimeType, track.StreamID(), track.ID())
 		if cb := s.videoTrackHandler(); cb != nil {
 			cb(track, receiver)
 		}
@@ -560,6 +562,11 @@ func (s *Session) handleSubscriberOffer(payload map[string]any) {
 }
 
 func (s *Session) sendPublisherOffer() {
+	if err := s.sendPublisherTrackAdds(); err != nil {
+		logger.Debugf("send publisher track add error: %v", err)
+		return
+	}
+
 	offer, err := s.pcPub.CreateOffer(nil)
 	if err != nil {
 		logger.Debugf("create pub offer error: %v", err)
@@ -588,6 +595,46 @@ func (s *Session) sendPublisherOffer() {
 	s.wsMu.Unlock()
 }
 
+func (s *Session) sendPublisherTrackAdds() error {
+	s.videoTrackMu.RLock()
+	tracks := append([]webrtc.TrackLocal(nil), s.videoTracks...)
+	s.videoTrackMu.RUnlock()
+
+	for _, track := range tracks {
+		if track == nil || track.Kind() != webrtc.RTPCodecTypeVideo {
+			continue
+		}
+		if err := s.sendPublisherTrackAdd("VIDEO", "CAMERA", false); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *Session) sendPublisherTrackAdd(trackType, source string, muted bool) error {
+	s.wsMu.Lock()
+	defer s.wsMu.Unlock()
+
+	if err := s.ws.WriteJSON(map[string]any{
+		keyRoomID:    s.roomID,
+		keyEvent:     "media-in",
+		"groupId":    s.groupID,
+		keyRequestID: uuid.New().String(),
+		keyPayload: map[string]any{
+			"method": "rtc:track:add",
+			"cid":    uuid.New().String(),
+			"track": map[string]any{
+				"type":   trackType,
+				"source": source,
+				"muted":  muted,
+			},
+		},
+	}); err != nil {
+		return fmt.Errorf("write track add json: %w", err)
+	}
+	return nil
+}
+
 func (s *Session) handlePublisherAnswer(payload map[string]any) {
 	desc, _ := payload["description"].(map[string]any)
 	sdp, _ := desc["sdp"].(string)

internal/engine/salutejazz/session_helpers_test.go

@@ -3,8 +3,11 @@ package salutejazz
 import (
 	"context"
 	"errors"
+	"net/http"
+	"net/http/httptest"
 	"testing"
 
+	"github.com/gorilla/websocket"
 	"github.com/pion/webrtc/v4"
 )
 
@@ -110,3 +113,59 @@ func TestSessionCanSendVideoOnlyModes(t *testing.T) {
 		t.Fatal("CanSend() = true for closed session")
 	}
 }
+
+func TestSendPublisherTrackAddWritesJazzPayload(t *testing.T) {
+	msgCh := make(chan map[string]any, 1)
+	upgrader := websocket.Upgrader{}
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		conn, err := upgrader.Upgrade(w, r, nil)
+		if err != nil {
+			t.Errorf("upgrade websocket: %v", err)
+			return
+		}
+		defer func() { _ = conn.Close() }()
+
+		var msg map[string]any
+		if err := conn.ReadJSON(&msg); err != nil {
+			t.Errorf("read json: %v", err)
+			return
+		}
+		msgCh <- msg
+	}))
+	defer server.Close()
+
+	wsURL := "ws" + server.URL[len("http"):]
+	conn, _, err := websocket.DefaultDialer.Dial(wsURL, nil)
+	if err != nil {
+		t.Fatalf("dial websocket: %v", err)
+	}
+	defer func() { _ = conn.Close() }()
+
+	s := &Session{
+		roomID:  "room-1",
+		groupID: "group-1",
+		ws:      conn,
+	}
+	if err := s.sendPublisherTrackAdd("VIDEO", "CAMERA", false); err != nil {
+		t.Fatalf("sendPublisherTrackAdd() error = %v", err)
+	}
+
+	msg := <-msgCh
+	if msg[keyRoomID] != "room-1" || msg[keyEvent] != "media-in" || msg["groupId"] != "group-1" {
+		t.Fatalf("unexpected envelope: %+v", msg)
+	}
+	payload, ok := msg[keyPayload].(map[string]any)
+	if !ok {
+		t.Fatalf("payload missing or wrong type: %+v", msg[keyPayload])
+	}
+	if payload["method"] != "rtc:track:add" {
+		t.Fatalf("method = %v, want rtc:track:add", payload["method"])
+	}
+	track, ok := payload["track"].(map[string]any)
+	if !ok {
+		t.Fatalf("track missing or wrong type: %+v", payload["track"])
+	}
+	if track["type"] != "VIDEO" || track["source"] != "CAMERA" || track["muted"] != false {
+		t.Fatalf("track = %+v, want video camera unmuted", track)
+	}
+}