Is it possible to hide or show certain pages according to certain conditions?

You can effectively show and hide pages in a PDF by creating a Template for each page that you want to show or hide. To function properly in both Acrobat and Reader, hidden pages can be spawned to the end or to a specific page number in the file. Spawned pages can then be "deleted" which only deletes the spawned duplicate of the template page which will still exist to be spawned again when needed.

To "show"a page use...

this.getTemplate("myTemplate").spawn();