OnvifServer C++ lib. Implementation of the ONVIF server with Profile S and M support

class OnvifServer
{
public:
    /// Type definition for the ONVIF message handler callback function.
    using onvif_handler_t = ONVIF_RET (*)(ONVIF_DEVICE *, ONVIF_MSG_TYPE, ...);

    /// Get string of current library version.
    static std::string getVersion();

    /// Initialize the ONVIF server with the JSON configuration string
    /// and a global handler callback.
    bool init(const std::string& jsonConfig, onvif_handler_t callback);

    /// Initialize the ONVIF server with the function pointers to initialize
    /// the supported analytics rules and modules. This method is OPTIONAL.
    void initAnalytics(void (*rulesInit)(onvif_SupportedRules *),
                       void (*modulesInit)(onvif_SupportedAnalyticsModules *));

    /// Start the ONVIF server.
    bool start();

    /// Stop the ONVIF server.
    bool stop();

    /// Set the streaming capabilities of server device that onvif server will use.
    void setStreamingCapabilities(bool rtpMulticast, bool rtpRtspTcp);
};

#include <iostream>
#include <string>
#include <thread>
#include <chrono>
#include "OnvifImage.h"
#include "OnvifServer.h"
#include "OnvifGlobalHandler.h"
#include "DefaultConfigContent.h"

/// ONVIF callback function. This function handles ONVIF messages.
ONVIF_RET onvifCallback(ONVIF_DEVICE *p_device, ONVIF_MSG_TYPE msg_type, ...)
{
    va_list args;
    va_start(args, msg_type);

    // Unless request is rejected explicitly, better to return ONVIF_OK
    // for many requests for test tool compatibility.
    ONVIF_RET ret = ONVIF_OK;

    // Check the message type and handle it accordingly.
    switch (msg_type)
    {
        // Handle SetImagingSettings request.
        case SetImagingSettings:
        {
            auto vsl = va_arg(args, VideoSourceList *);
            auto req = va_arg(args, img_SetImagingSettings_REQ *);

            // Get token. Camera token is defined in config file.
            std::string cameraName(vsl->VideoSource.token);

            // Some logic depends on camera name if we have multiple cameras.

            // Apply these settings to your camera. 
            req->ImagingSettings.Brightness;
            req->ImagingSettings.Contrast;
            req->ImagingSettings.ColorSaturation;
            break;
        }
        // Handle GetImagingSettings request.
        case GetImagingSettings:
        {
            auto vsl = va_arg(args, VideoSourceList *);
            auto req = va_arg(args, img_GetImagingSettings_REQ *);

            // Get token. Camera token is defined in config file.
            std::string cameraName(vsl->VideoSource.token);

            // Some logic depends on camera name if we have multiple cameras.

            // Fill image settings.
            auto imageSettings = &vsl->ImagingSettings;
            imageSettings->Brightness = 25.0f;      // Example value.
            imageSettings->Contrast = 50.0f;        // Example value.
            imageSettings->ColorSaturation = 75.0f; // Example value.
            break;
        }

        // ... Other cases for handling different ONVIF messages ...
    }

    va_end(args);

    // Return the result of the operation.
    return ret;
}

/// Entry point.
int main(int argc, char **argv)
{
    // Create ONVIF server object.
    cr::onvif::OnvifServer onvifServer;

    // Init ONVIF server with the JSON configuration and callback function.
    if (!onvifServer.init(g_defaultConfigContent, onvifCallback))
        return -1;

    // Start ONVIF server.
    if (!onvifServer.start())
        return -1;

    // Wait key press to stop the server.
    std::cout << "ONVIF server started. Press Enter to stop..." << std::endl;
    std::cin.get();

    onvifServer.stop();

    return 0;
}