Apply template based upon filename

Hi,
I would like to be able to apply 1 of 2 different AREN templates, based upon whether the filename contains the word " .and. " or " and ".

Filename examples car.and.bike01.jpg, car.and.bike02.jpg, tent.and.bike07.jpg, tent04.jpg

The last example would be for the second AREN template.

I had hoped to use the scripting method, and an If Else statement, but whilst i know a little C++, i am not familiar with JS.

For instance, how to parse filename string and identify "and" ?

So
If (filename contains "and")
{
Apply AREN template 01
}
Else
{
Apply AREN template 02
}

Any help appreciated.

Thanks!