void ConfigShadow::reconfigureWithConfigShadow()

in source/shadow/ConfigShadow.cpp [396:473]
69 lines of code
10 McCabe index (conditional complexity)

void ConfigShadow::reconfigureWithConfigShadow(
    std::shared_ptr<SharedCrtResourceManager> resourceManager,
    PlainConfig &config)
{
    IotShadowClient iotShadowClient(resourceManager.get()->getConnection());
    thingName = *config.thingName;
    if (!subscribeGetAndUpdateNamedShadowTopics(iotShadowClient))
    {
        LOGM_ERROR(
            TAG, "Encounter error while subscribing pertinent %s shadow topic from cloud", DEFAULT_CONFIG_SHADOW_NAME);
        return;
    }

    if (!fetchRemoteConfigShadow(iotShadowClient))
    {
        LOGM_ERROR(
            TAG, "Encounter error while fetching device client config shadow from cloud", DEFAULT_CONFIG_SHADOW_NAME);
        return;
    }

    auto futureConfigShadowExistsPromise = configShadowExistsPromise.get_future();
    if (futureConfigShadowExistsPromise.wait_for(std::chrono::seconds(DEFAULT_WAIT_TIME_SECONDS)) ==
        future_status::timeout)
    {
        LOGM_ERROR(
            TAG,
            "Waiting for %s getNamedShadow response time out or get unexpected error from service",
            DEFAULT_CONFIG_SHADOW_NAME);
        return;
    }

    if (futureConfigShadowExistsPromise.get() && configDelta.has_value())
    {
        // config shadow and delta exists, resetting the local config first and then updating config shaodw
        if (configDelta)
        {
            LOG_INFO(
                TAG, "Detect the delta of configuration in the config shadow, reconfiguring the device client now.");

            if (!desiredConfig.has_value())
            {
                LOG_ERROR(
                    TAG, "Fail to fetch the desired value in config shaodw, aborting the configuration update now");
                return;
            }

            JsonObject configDesiredObject = configDelta.value();
            if (!configDesiredObject.WasParseSuccessful())
            {
                LOGM_ERROR(
                    TAG,
                    "Couldn't parse JSON config desired. GetErrorMessage returns: %s",
                    configDesiredObject.GetErrorMessage().c_str());
                return;
            }

            JsonObject configDeltaObject = configDelta.value();
            if (!configDeltaObject.WasParseSuccessful())
            {
                LOGM_ERROR(
                    TAG,
                    "Couldn't parse JSON config delta. GetErrorMessage returns: %s",
                    configDeltaObject.GetErrorMessage().c_str());
                return;
            }

            JsonView desiredJsonView = desiredConfig->View();
            JsonView deltaJsonView = configDelta->View();
            resetClientConfigWithJSON(config, deltaJsonView, desiredJsonView);
        }
        updateShadowWithLocalConfig(iotShadowClient, config);
    }
    else
    {
        // config shadow doesn't exists, store the device client configuration into config shadow
        updateShadowWithLocalConfig(iotShadowClient, config);
    }
}