switch theme module similar to IP Login
I design and maintain the company intranet. The intranet is also accessible by our centres based in our outlaying islands. Note the Solomon Islands is made up of sparsely, scattered islands and we are based in almost all main islands. These centers normally do not have decent connectivity so our full featured intranet site & theme is practically impossible to view in our provincial centers.
I have looked at most existing modules (switchtheme, taxonomy_theme etc) but none seem to fit my requirement so I am attempting to hack the IP Login module but with little success (because I am a newbie at module development).
I would like the module to automatically detect the IP range but instead of logging in users like the IP Login module does, it should instead set a lightweight theme for our provincial users based on the IP Range returned. It does not need to log the user in. This is because we use DHCP and IP Login just does not work in that scenario. If IP Login did work with DHCP, it would have been the most ideal solution since all users would have already had their themes set up in User Settings. In the absence of that functionality, I just desperately need a module to automatically turn on a theme based on IP Range.
Any helpful pointers on what possible course of action to take or functions to use will help me a lot.

no help but resolved
sadly, there were no pointers for me through this forum.
but I did manage to resolve my issue by modifying settings.php
However, I am working on making it a module to allow for more flexibility.
Simplicity is an art
could you please share your tricks?
could you please share your tricks?
works but not most ideal solution
i must admit, this is not the most ideal solution since it does disable the ability of individual users to change themes as the code in settings.php overrides that ability. I may be wrong! Plus, it is not as flexible as using a module.
However, my solution is in settings.php, I used: $_SERVER['REMOTE_ADDR'] to get the ip.
Using 'explode'/'implode', I strip the range I need (of course you could use substr()). I then compare the range with our ip ranges which I declared as constants using a simple if/else, setting the theme using $conf['theme_default']='which theme from sites/all/themes' based on which range is determined. It works.
But I am currently trying to convert that same concept into a custom module so that it will be more flexible. The custom module should be based on the above concept & those in IP Login. That way, the ranges can be set in Profile and compared with the ip range returned. I think that is a more elegant way of doing this. Better still is if IP Login worked with DHCP as it will automatically log in the user and use theme already set in each user preference.
Cheers, I am still open for suggestions.
Simplicity is an art