From c70c3a58f1c5ef13a28ad19cc816706a318fad34 Mon Sep 17 00:00:00 2001
From: Alexey Khit <alexey.khit@gmail.com>
Date: Wed, 1 Mar 2023 18:01:11 +0300
Subject: [PATCH] Add media list option to webrtc create function

---
 cmd/webrtc/client.go | 14 ++++++++++++--
 pkg/webrtc/client.go | 25 ++++++++++++++++---------
 2 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/cmd/webrtc/client.go b/cmd/webrtc/client.go
index c72d827b..2819fb00 100644
--- a/cmd/webrtc/client.go
+++ b/cmd/webrtc/client.go
@@ -60,8 +60,13 @@ func asyncClient(url string) (streamer.Producer, error) {
 		}
 	})
 
+	medias := []*streamer.Media{
+		{Kind: streamer.KindVideo, Direction: streamer.DirectionRecvonly},
+		{Kind: streamer.KindAudio, Direction: streamer.DirectionRecvonly},
+	}
+
 	// 3. Create offer
-	offer, err := prod.CreateOffer()
+	offer, err := prod.CreateOffer(medias)
 	if err != nil {
 		return nil, err
 	}
@@ -123,8 +128,13 @@ func syncClient(url string) (streamer.Producer, error) {
 
 	prod := webrtc.NewConn(pc)
 
+	medias := []*streamer.Media{
+		{Kind: streamer.KindVideo, Direction: streamer.DirectionRecvonly},
+		{Kind: streamer.KindAudio, Direction: streamer.DirectionRecvonly},
+	}
+
 	// 3. Create offer
-	offer, err := prod.CreateCompleteOffer()
+	offer, err := prod.CreateCompleteOffer(medias)
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/webrtc/client.go b/pkg/webrtc/client.go
index 715b8a11..d39a547d 100644
--- a/pkg/webrtc/client.go
+++ b/pkg/webrtc/client.go
@@ -6,10 +6,16 @@ import (
 	"github.com/pion/webrtc/v3"
 )
 
-func (c *Conn) CreateOffer() (string, error) {
-	init := webrtc.RTPTransceiverInit{Direction: webrtc.RTPTransceiverDirectionRecvonly}
-	_, _ = c.pc.AddTransceiverFromKind(webrtc.RTPCodecTypeVideo, init)
-	_, _ = c.pc.AddTransceiverFromKind(webrtc.RTPCodecTypeAudio, init)
+func (c *Conn) CreateOffer(medias []*streamer.Media) (string, error) {
+	for _, media := range medias {
+		if _, err := c.pc.AddTransceiverFromKind(
+			webrtc.NewRTPCodecType(media.Kind), webrtc.RTPTransceiverInit{
+				Direction: webrtc.NewRTPTransceiverDirection(media.Direction),
+			},
+		); err != nil {
+			return "", err
+		}
+	}
 
 	desc, err := c.pc.CreateOffer(nil)
 	if err != nil {
@@ -20,11 +26,11 @@ func (c *Conn) CreateOffer() (string, error) {
 		return "", err
 	}
 
-	return desc.SDP, nil
+	return c.pc.LocalDescription().SDP, nil
 }
 
-func (c *Conn) CreateCompleteOffer() (string, error) {
-	if _, err := c.CreateOffer(); err != nil {
+func (c *Conn) CreateCompleteOffer(medias []*streamer.Media) (string, error) {
+	if _, err := c.CreateOffer(medias); err != nil {
 		return "", err
 	}
 
@@ -47,13 +53,14 @@ func (c *Conn) SetAnswer(answer string) (err error) {
 
 	// sort medias, so video will always be before audio
 	// and ignore application media from Hass default lovelace card
+	// ignore media without direction (inactive media)
 	for _, media := range medias {
-		if media.Kind == streamer.KindVideo {
+		if media.Kind == streamer.KindVideo && media.Direction != "" {
 			c.medias = append(c.medias, media)
 		}
 	}
 	for _, media := range medias {
-		if media.Kind == streamer.KindAudio {
+		if media.Kind == streamer.KindAudio && media.Direction != "" {
 			c.medias = append(c.medias, media)
 		}
 	}