Have a look at this Re^2: splitting data. If you replace parantheses by braces, you get a parser for nested structures. If you add code that stores data in hashes and check for the prior existence of the key, this could be working.

UPDATE:  I spent some time following my own advice but could not make 
+it work.  Apologies, if you wasted time trying it.  Please post the r
+esult should you have succeeded.
[download]