public async Task AssertDeviceConnectionClosedAsync()

in DeviceBridge/Services/ConnectionManager.cs [323:388]
57 lines of code
9 McCabe index (conditional complexity)

        public async Task AssertDeviceConnectionClosedAsync(string deviceId, bool temporary = false)
        {
            _logger.Info("Attempting to tear down {connectionType} connection for device {deviceId}", temporary ? "Temporary" : "Permanent", deviceId);

            var mutex = _clientSemaphores.GetOrAdd(deviceId, new SemaphoreSlim(1, 1));
            await mutex.WaitAsync();

            try
            {
                _logger.Info("Acquired connection lock for device {deviceId}", deviceId);

                // Attempt to remove the permanent or temporary connection from the list
                if (temporary)
                {
                    var currentTime = DateTimeOffset.UtcNow.ToUnixTimeSeconds();

                    if (_hasTemporaryConnectionUntil.TryGetValue(deviceId, out long shouldLiveUntil))
                    {
                        if (currentTime > shouldLiveUntil)
                        {
                            _hasTemporaryConnectionUntil.TryRemove(deviceId, out _);
                        }
                        else
                        {
                            _logger.Info("Attempted to tear down temporary connection for device {deviceId}, but connection has not yet expired", deviceId);
                            return;
                        }
                    }
                    else
                    {
                        _logger.Info("Attempted to tear down temporary connection for device {deviceId}, but a temporary connection wasn't found", deviceId);
                        return;
                    }
                }
                else
                {
                    if (!_hasPermanentConnection.TryRemove(deviceId, out _))
                    {
                        _logger.Info("Attempted to tear down permanent connection for device {deviceId}, but a permanent connection wasn't found", deviceId);
                        return;
                    }
                }

                // Do not actually close client if a permanent or temporary connection still exists.
                if (_hasPermanentConnection.TryGetValue(deviceId, out _) || _hasTemporaryConnectionUntil.TryGetValue(deviceId, out _))
                {
                    _logger.Info("Attempted to tear down connection for device {deviceId}, but a permanent or temporary connection for this device still exists.", deviceId);
                    return;
                }

                if (!_clients.TryRemove(deviceId, out DeviceClient client))
                {
                    _logger.Info("Connection for device {deviceId} doesn't exist", deviceId);
                    return;
                }

                await client.CloseAsync();
                client.Dispose();
                client.SetConnectionStatusChangesHandler(null);
                _logger.Info("Closed connection for device {deviceId}", deviceId);
            }
            finally
            {
                mutex.Release();
            }
        }