I tried many combinations but none works. I trying to write rewrite rule which:

1. Assume URL of <http://example.com/project/big_bunny>
2. When user visit site rewrite first try to read file /cache/project/big\_bunny.html but only if there is no any get or post data
3. If there is no cache rewrite process standard router rule: index.php?\_rt=$1 [L,QSA]

Any suggestions?