mod_rewrite rules in .htaccess - apache

Question

I want to do change my document root using rewrite rules in my .htaccess file, and also redirect all requests to index.php except static resources
In other words:
if a file with the path prepended with www exists (i.e. www/{%request_uri}):
http://domain.com/css/main.css should be rewritten to http://domain.com/www/css/main.css
if that file does not exist, redirect to the app main entry point www/index.php:
e.g.
http://domain.com should be rewritten to http://domain.com/www/index.php
http://domain.com/hello should be rewritten to http://domain.com/www/index.php/hello
http://domain.com/hello?a=1 should be rewritten to http://domain.com/www/index.php/hello?a=1
I tried variations, however either it gives us 500 internal server error, or infinite loop. Here is one that gives 500 internal server error:
# try to find it in www/
RewriteCond {%DOCUMENT_ROOT}/www%{REQUEST_URI} -f
RewriteCond {%DOCUMENT_ROOT}/www%{REQUEST_URI} -d
RewriteRule ^(.+) www/$1 [L]
RewriteRule ^(.*) www/index.php/$1 [L]
This one also:
RewriteCond %{REQUEST_URI} !www/
RewriteRule (.*) /www/$1
RewriteCond {%REQUEST_FILENAME} !-f
RewriteCond {%REQUEST_FILENAME} !-d
RewriteRule www/(.*) /www/index.php/$1 [PT,L]
Can anyone help?

Answer 1

I think that's impossible with a single .htaccess but it's possible with two.
You need one in your root directory, /.htaccess:
RewriteEngine on
RewriteBase /
# We don't want infinite rewriting.
RewriteCond %{REQUEST_URI} !www/.*$
RewriteRule ^(.*)$ www/$1 [L]
And another in your www directory, /www/.htaccess:
RewriteEngine on
RewriteBase /www
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php/$1 [L]

Answer 2

Well actually I made a stupid mistake! The % sign should be outside of the {} bracket!
This can be done in one .htaccess in root dir:
RewriteEngine on
RewriteCond %{REQUEST_URI} !www/
RewriteRule ^(.*)$ www/$1
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^www/(.*)$ www/index.php/$1 [L]