From f35fdda7a24f31f05435c3c6a325e2d596d1cfb6 Mon Sep 17 00:00:00 2001
From: pavel <pavelflegr@gmail.com>
Date: Tue, 24 Feb 2026 00:55:49 +0100
Subject: [PATCH] m

---
 static/app.js | 56 +++++++++++++++++++++++++++++++++------------------
 1 file changed, 36 insertions(+), 20 deletions(-)

diff --git a/static/app.js b/static/app.js
index fca5265..5d5deb4 100644
--- a/static/app.js
+++ b/static/app.js
@@ -675,9 +675,7 @@ function ensurePeerConnection(peerId) {
 
   pc.onnegotiationneeded = async () => {
     try {
-      if (shouldInitiateOffer(peerId)) {
-        await sendOffer(peerId);
-      }
+      await sendOffer(peerId);
     } catch (err) {
       console.error("negotiation failed", err);
     }
@@ -701,25 +699,43 @@ async function sendOffer(peerId) {
 
 async function handleSignal(fromPeerId, kind, data) {
   const pc = ensurePeerConnection(fromPeerId);
+  const polite = !shouldInitiateOffer(fromPeerId);
 
-  if (kind === "offer") {
-    await pc.setRemoteDescription(new RTCSessionDescription(data));
-    const answer = await pc.createAnswer();
-    await pc.setLocalDescription(answer);
-    state.voice.ws.send(JSON.stringify({
-      type: "signal",
-      to_user_id: fromPeerId,
-      kind: "answer",
-      data: answer,
-    }));
-  } else if (kind === "answer") {
-    await pc.setRemoteDescription(new RTCSessionDescription(data));
-  } else if (kind === "ice") {
-    try {
-      await pc.addIceCandidate(data ? new RTCIceCandidate(data) : null);
-    } catch (err) {
-      console.warn("failed to add ice candidate", err);
+  try {
+    if (kind === "offer") {
+      const offerCollision = (pc.signalingState !== "stable");
+      if (offerCollision) {
+        if (!polite) return;
+        await Promise.all([
+          pc.setLocalDescription({ type: "rollback" }),
+          pc.setRemoteDescription(new RTCSessionDescription(data))
+        ]);
+      } else {
+        await pc.setRemoteDescription(new RTCSessionDescription(data));
+      }
+      const answer = await pc.createAnswer();
+      await pc.setLocalDescription(answer);
+      state.voice.ws.send(JSON.stringify({
+        type: "signal",
+        to_user_id: fromPeerId,
+        kind: "answer",
+        data: answer,
+      }));
+    } else if (kind === "answer") {
+      await pc.setRemoteDescription(new RTCSessionDescription(data));
+    } else if (kind === "ice") {
+      try {
+        await pc.addIceCandidate(data ? new RTCIceCandidate(data) : null);
+      } catch (err) {
+        if (pc.signalingState !== "stable") {
+          // Ignore ICE candidates during negotiation
+        } else {
+          console.warn("failed to add ice candidate", err);
+        }
+      }
     }
+  } catch (err) {
+    console.error("handleSignal failed", err);
   }
 }