Auto download from subscribed users and search results. Just like uTorrent RSS downloader.
First we need to need the search results be refreshable, every 15mins or 30mins, then we need a function to subsribe to users.

Now we can make auto download rules, in the rule, we can custom:
1. Subsribe source, can be:
     A search result, and the frequence to refresh.
     User names.
2. Filter, with wildcard or regxp support, include filter and exclude filter.
3. (Optional) Start time and end time of this rule.
4. Download times (min value = 1), if a file is downloaded and I've checked it, then deleted it, then the filter meets this file again, the download times settings can decide to download it again or pass it.
5. Download position (current fopnu download position settings is poor).