When an existing group call participant invites a new peer via
CallController.invitePeer(), the caller connects to the invitee via the
normal offer/answer flow, but the other existing callees were never
establishing their own PeerConnections to the new peer — breaking the
full-mesh invariant.
Root cause: the NIP-AC "callee-to-callee mesh setup" mechanism relies on
each callee observing the others' CallAnswers during its own ringing
window and applying a symmetric "lower pubkey initiates" tiebreaker.
A mid-call invitee's ringing window happens after all existing callees
have already answered, so the invitee's discoveredCalleePeers set is
empty. Worse, if the invitee's pubkey is higher than an existing
callee's, that callee also stays passive (waiting for the invitee to
initiate), and no mesh connection is ever attempted between them.
Fix — break the symmetry on mid-call invites:
- CallManager.onCallAnswered now expands peerPubKeys when an answer
arrives in Connected (or Connecting) state from a peer that is not
yet in the tracked group membership. This keeps the UI and state
consistent with the expanded group and gives CallController a clear
hook via onAnswerReceived.
- CallController.onCallAnswerReceived splits the NO_SESSION case:
* Connected state → mid-call invite. Unconditionally initiate a
mesh CallOffer to the new peer. The invitee stays passive, so
exactly one side initiates per pair and glare is structurally
impossible.
* Connecting state → initial-call mesh observation. Keep the
existing lower-pubkey tiebreaker via onNewPeerInGroupCall to
avoid glare with the symmetric peer.
This fix uses the existing event kinds (CallOffer 25050 and CallAnswer
25051) — no new kinds or tags are required. NIP-AC.md is updated with
a new "Mid-Call Mesh Expansion" subsection under "Inviting New Peers"
documenting the asymmetric rule and a full-flow diagram.
Tests in CallManagerTest cover:
- Mid-call invitee's broadcast answer expands existing callee's
peerPubKeys in Connected state.
- Same expansion works in Connecting state (existing callee still
handshaking with caller when the invitee joins).
- Initial-call answers from already-tracked peers do NOT trigger the
expansion branch (regression guard).
- Full end-to-end 3-way flow exercising Alice, Bob, Carol managers.
https://claude.ai/code/session_01XSPDbahLwHs9sdF5XfRvHB
Claude
d087e1ac13