initial commit — SIP B2BUA + WebRTC bridge with Rust codec engine

Full-featured SIP router with multi-provider trunking, browser softphone
via WebRTC, real-time Opus/G.722/PCM transcoding in Rust, RNNoise ML
noise suppression, Kokoro neural TTS announcements, and a Lit-based
web dashboard with live call monitoring and REST API.

ts/webrtcbridge.ts

@@ -0,0 +1,124 @@
+/**
+ * WebRTC signaling — browser device registration and WebSocket dispatch.
+ *
+ * This module handles ONLY the signaling side:
+ * - Browser device registration/unregistration via WebSocket
+ * - WS → deviceId mapping
+ *
+ * All WebRTC media logic (PeerConnection, RTP, transcoding) lives in
+ * ts/call/webrtc-leg.ts and is managed by the CallManager.
+ */
+
+import { WebSocket } from 'ws';
+import { registerBrowserDevice, unregisterBrowserDevice, shortHash } from './registrar.ts';
+
+// ---------------------------------------------------------------------------
+// Config
+// ---------------------------------------------------------------------------
+
+interface IWebRtcSignalingConfig {
+  log: (msg: string) => void;
+}
+
+let config: IWebRtcSignalingConfig;
+
+// ---------------------------------------------------------------------------
+// State: WS ↔ deviceId mapping
+// ---------------------------------------------------------------------------
+
+const wsToSession = new WeakMap<WebSocket, string>();
+const deviceIdToWs = new Map<string, WebSocket>();
+
+// ---------------------------------------------------------------------------
+// Public API
+// ---------------------------------------------------------------------------
+
+export function initWebRtcSignaling(cfg: IWebRtcSignalingConfig): void {
+  config = cfg;
+}
+
+/**
+ * Handle a WebRTC signaling message from a browser client.
+ * Only handles registration; offer/ice/hangup are routed through CallManager.
+ */
+export function handleWebRtcSignaling(
+  ws: WebSocket,
+  message: { type: string; sessionId?: string; [key: string]: any },
+): void {
+  const { type } = message;
+
+  if (type === 'webrtc-register') {
+    handleRegister(ws, message.sessionId!, message.userAgent, message._remoteIp);
+  }
+  // Other webrtc-* types (offer, ice, hangup, accept) are handled
+  // by the CallManager via frontend.ts WebSocket handler.
+}
+
+/**
+ * Send a message to a specific browser device by its device ID.
+ */
+export function sendToBrowserDevice(deviceId: string, data: unknown): boolean {
+  const ws = deviceIdToWs.get(deviceId);
+  if (!ws) return false;
+  wsSend(ws, data);
+  return true;
+}
+
+/**
+ * Get the WebSocket for a browser device (used by CallManager to create WebRtcLegs).
+ */
+export function getBrowserDeviceWs(deviceId: string): WebSocket | null {
+  return deviceIdToWs.get(deviceId) ?? null;
+}
+
+/**
+ * Get all registered browser device IDs.
+ */
+export function getAllBrowserDeviceIds(): string[] {
+  return [...deviceIdToWs.keys()];
+}
+
+// ---------------------------------------------------------------------------
+// Registration
+// ---------------------------------------------------------------------------
+
+function handleRegister(ws: WebSocket, sessionId: string, userAgent?: string, remoteIp?: string): void {
+  // Clean up any previous browser device from this same WS connection.
+  const prevSession = wsToSession.get(ws);
+  if (prevSession && prevSession !== sessionId) {
+    unregisterBrowserDevice(prevSession);
+  }
+
+  unregisterBrowserDevice(sessionId);
+  registerBrowserDevice(sessionId, userAgent, remoteIp);
+  wsToSession.set(ws, sessionId);
+  config.log(`[webrtc:${sessionId.slice(0, 8)}] browser registered as device`);
+
+  const deviceId = `browser-${shortHash(sessionId)}`;
+  deviceIdToWs.set(deviceId, ws);
+
+  // Echo back the assigned device ID.
+  wsSend(ws, { type: 'webrtc-registered', deviceId });
+
+  // Only add close handler once per WS connection.
+  if (!prevSession) {
+    ws.on('close', () => {
+      const sid = wsToSession.get(ws) || sessionId;
+      config.log(`[webrtc:${sid.slice(0, 8)}] browser disconnected`);
+      deviceIdToWs.delete(`browser-${shortHash(sid)}`);
+      unregisterBrowserDevice(sid);
+    });
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+function wsSend(ws: WebSocket, data: unknown): void {
+  try {
+    if (ws.readyState === WebSocket.OPEN) {
+      ws.send(JSON.stringify(data));
+    }
+  } catch { /* ignore */ }
+}