[TYPO3-english] detect facebook iframe - load different template

[Denis Torgal]

Hi friends,

i have a template for my website, i want to add this website to facebook 
by iframe. If someone opens the facebook page, i want to detect this and 
load a different template.

I could check this by JavaScript, but don't like this solution.

Is there a Condition expression like the browser detection to fulfill this?
If not - is it possible to check this by php?

thanks in advance

Denis