How to make a slideshow shortcode based on the WordPress gallery shortcode? [closed]

I would do something similar to this:

return '<div class="slideshow">'.do_shortcode( '.'"]' ).'</div>';

In other words, wrap around the existing short code instead of ending up with a frankenstein version of it. You can then use the slideshow div to select against using jquery and whichever javascript gallery you want to use. How you would do that is beyond the scope of this site