user and admin notifications

Hello. Please could you tell me if it is possible to create a predefinied message on backend with tag system so to replace tag with some data as for example name of user.
In this way the component will send these notification messages in the following cases:
1) message to admin if user upload a file;
2) message to user creator of file or document if other user download it.
3) message to user recipient if user creator share file or document with him

Obviously admin can enable or disable every single notifications
You should integrate the notificiations feature by adding message to recipient user if document creator assign it to him.
Thanks
Best regards

Please could you reply me. This is a very important addon.
Thanks.

Best regards