פיתוח מימוש המקשר עמוד אינטרנט לרכיב Plugin

We'd like to get a sample providing the following functionality:
- Webpage icon to execute plugin method
- Clicking the icon detects if plugin is available
- If plugin is not available, direct user execute an installation for the plugin, automatically detect when the plugin has been installed and continue to next step
- If plugin is installed, call a single method in the plugin which merely pops a message box saying "Hi!"

* Must support latest versions of IE, Firefox and Chrome; Safari is an advantage.
* Implementation can use a browser-compatibility framework or open-source.
* Plugin must be based on native C++ and Win32 API, not JavaScript or .NET.