Move cmd module to internal

internal/webrtc/candidates.go

@@ -0,0 +1,122 @@
+package webrtc
+
+import (
+	"github.com/AlexxIT/go2rtc/internal/api"
+	"github.com/AlexxIT/go2rtc/pkg/webrtc"
+	"github.com/pion/sdp/v3"
+	"strconv"
+	"strings"
+)
+
+type Address struct {
+	Host string
+	Port int
+}
+
+var addresses []Address
+
+func AddCandidate(address string) {
+	var port int
+
+	// try to get port from address string
+	if i := strings.LastIndexByte(address, ':'); i > 0 {
+		if v, _ := strconv.Atoi(address[i+1:]); v != 0 {
+			address = address[:i]
+			port = v
+		}
+	}
+
+	// use default WebRTC port
+	if port == 0 {
+		port, _ = strconv.Atoi(Port)
+	}
+
+	addresses = append(addresses, Address{Host: address, Port: port})
+}
+
+func GetCandidates() (candidates []string) {
+	for _, address := range addresses {
+		// using stun server for receive public IP-address
+		if address.Host == "stun" {
+			ip, err := webrtc.GetCachedPublicIP()
+			if err != nil {
+				continue
+			}
+			// this is a copy, original host unchanged
+			address.Host = ip.String()
+		}
+
+		candidates = append(
+			candidates,
+			webrtc.CandidateManualHostUDP(address.Host, address.Port),
+			webrtc.CandidateManualHostTCPPassive(address.Host, address.Port),
+		)
+	}
+
+	return
+}
+
+func asyncCandidates(tr *api.Transport, cons *webrtc.Conn) {
+	tr.WithContext(func(ctx map[any]any) {
+		if candidates, ok := ctx["candidate"].([]string); ok {
+			// process candidates that receive before this moment
+			for _, candidate := range candidates {
+				_ = cons.AddCandidate(candidate)
+			}
+
+			// remove already processed candidates
+			delete(ctx, "candidate")
+		}
+
+		// set variable for process candidates after this moment
+		ctx["webrtc"] = cons
+	})
+
+	for _, candidate := range GetCandidates() {
+		log.Trace().Str("candidate", candidate).Msg("[webrtc] config")
+		tr.Write(&api.Message{Type: "webrtc/candidate", Value: candidate})
+	}
+}
+
+func syncCanditates(answer string) (string, error) {
+	if len(addresses) == 0 {
+		return answer, nil
+	}
+
+	sd := &sdp.SessionDescription{}
+	if err := sd.Unmarshal([]byte(answer)); err != nil {
+		return "", err
+	}
+
+	md := sd.MediaDescriptions[0]
+
+	for _, candidate := range GetCandidates() {
+		md.WithPropertyAttribute(candidate)
+	}
+
+	data, err := sd.Marshal()
+	if err != nil {
+		return "", err
+	}
+
+	return string(data), nil
+}
+
+func candidateHandler(tr *api.Transport, msg *api.Message) error {
+	// process incoming candidate in sync function
+	tr.WithContext(func(ctx map[any]any) {
+		candidate := msg.String()
+		log.Trace().Str("candidate", candidate).Msg("[webrtc] remote")
+
+		if cons, ok := ctx["webrtc"].(*webrtc.Conn); ok {
+			// if webrtc.Server already initialized - process candidate
+			_ = cons.AddCandidate(candidate)
+		} else {
+			// or collect candidate and process it later
+			list, _ := ctx["candidate"].([]string)
+			ctx["candidate"] = append(list, candidate)
+		}
+	})
+
+	return nil
+}