/**
 * Deterministic WebRTC role election.
 *
 * Both ids must come from the **same signal server's identity space**. One human has a
 * separate account - and therefore a separate actor id - on every signal server they are
 * provisioned on, so comparing a home id against a foreign actor id is not antisymmetric:
 * each side compares its own home id against the other's foreign id, and both can elect
 * themselves initiator (glare) or neither can (no offer ever sent).
 */
export function shouldInitiatePeerConnection(
  localActorId: string | null | undefined,
  remoteActorId: string | null | undefined
): boolean {
  const local = localActorId?.trim();
  const remote = remoteActorId?.trim();

  if (!local || !remote)
    return false;

  if (local === remote)
    return false;

  return local < remote;
}

/**
 * Perfect-negotiation politeness, derived from the same election so the two can never
 * disagree: the elected initiator is the impolite side and keeps its offer, the other
 * side rolls back. Falls back to polite when the local actor id is unknown, so an
 * unidentified client yields instead of deadlocking the negotiation.
 */
export function isPoliteOnOfferCollision(
  localActorId: string | null | undefined,
  remoteActorId: string | null | undefined
): boolean {
  return !shouldInitiatePeerConnection(localActorId, remoteActorId);
}