registerCall method

void registerCall(Call call)

Registers a call so that its hold-status is observed.

When the call transitions to held it is added to heldCalls; when it transitions away from held it is removed. This mirrors the registerCall / hold-status-observer pattern in the Android SDK.

Idempotent: calling this multiple times for the same callId will only wire up the state-change listener once. This is important because the same Call object flows through both the invite handler (registered on receive) and acceptCall (re-registered on accept); without this guard, onCallStateChanged would be wrapped multiple times and _onCallStateChanged would fire N times per state transition.

Implementation

void registerCall(Call call) {
  final callId = call.callId;
  if (_registeredCallIds.contains(callId)) {
    GlobalLogger().d(
      'CallManager.registerCall: callId=$callId already registered, skipping',
    );
    return;
  }
  _registeredCallIds.add(callId);

  // Listen for state changes. When the call transitions to/from held we
  // update the held-calls list.
  // We attach a listener via the existing CallHandler callback chain by
  // wrapping the existing callback.
  final originalCallback = call.callHandler.onCallStateChanged;
  call.callHandler.onCallStateChanged = (CallState state) {
    originalCallback(state);
    _onCallStateChanged(call, state);
  };
}