RSS and Content Generating Script

I need a php script that can gather all the RSS and/or Atom feeds from an unlimited number of websites (the number of sites, and how many feeds/site must come from an exterior file). The script should ask for keywords and find the feeds related to those keywords, then it should create an index of all articles or feeds relating to the keywords. The script has to run a Cron Job each night to gather new content from the sources and update the index and sitemap. It should only grab new material with each pass. However, it should also leave all previously indexed content, adding to it with each new retrieval. The script then must generate a static page for each feed displaying the full contents of the feed, so that when a visitor clicks on a link in the index, they're taken to the on site static page and not the actual feed link. A link back to the feed source should be included at the bottom of each static page. The generated result page and static page must fit into any given template. The concept behind the project is to create an ever increasing content site based on keywords and drawn from RSS sources.