Big rewrite for WebRTC processing

pkg/webrtc/client.go

@@ -0,0 +1,34 @@
+package webrtc
+
+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)
+
+	desc, err := c.pc.CreateOffer(nil)
+	if err != nil {
+		return "", err
+	}
+
+	if err = c.pc.SetLocalDescription(desc); err != nil {
+		return "", err
+	}
+
+	return desc.SDP, nil
+}
+
+func (c *Conn) CreateCompleteOffer() (string, error) {
+	if _, err := c.CreateOffer(); err != nil {
+		return "", err
+	}
+
+	<-webrtc.GatheringCompletePromise(c.pc)
+	return c.pc.LocalDescription().SDP, nil
+}
+
+func (c *Conn) SetAnswer(answer string) (err error) {
+	desc := webrtc.SessionDescription{SDP: answer, Type: webrtc.SDPTypeAnswer}
+	return c.pc.SetRemoteDescription(desc)
+}