Nginx dynamic domain with redirect to root

gistfile1.bat

server {
        server_name ~^(:?(?<second>.+)\.)?(?<domain>[^.]+\.[^.]+)$;

	set $test "";
	if ($second !~ "^$") {
		set $test "${test}S";
	}
	if (-d /srv/virtual_hosts/$second.$domain) {
		set $test "${test}E";
	}
	if (-d /srv/virtual_hosts/$domain) {
                set $test "${test}D";
        }
	
	if ($test ~ "^SE") { # second set and exists
                set $sn $second.$domain;
       	}
	if ($test ~ "^SD") { # second set but folder does not exist, redirect to root
		rewrite ^(.*)$ http://$domain$1;
		return 303;
	}
	if ($test ~ "^D$") { # second not set, domain folder exists
		set $sn $domain;
	}
 
        root /srv/virtual_hosts/$sn/www;
        try_files $uri $uri/ /index.php;
	index index.php index.html;

	## Images and static content is treated different
	location ~* ^.+\.(jpg|jpeg|gif|css|png|js|ico|xml)$ {
		access_log        off;
		expires           30d;
		log_not_found     off;
	}

	location / {
		if (!-e $request_filename) {
			rewrite ^(.*)$ index.php last;
			break;
		}
	}

        # pass the PHP scripts to FastCGI (PHP-FPM) server listening on 127.0.0.1:9000
        location ~ \.php$ {
		include fastcgi_params;
		fastcgi_param PATH_INFO $fastcgi_script_name;
		fastcgi_param SCRIPT_FILENAME $document_root/$fastcgi_script_name;
		fastcgi_param SERVER_NAME $sn;
		fastcgi_pass 127.0.0.1:9000;		
        }
}

Request	Invoked Target
domain.tld	/domain.tld/www
sub.domain.tld	loads /sub.domain.tld/www if exists, otherwise redirects to domain.tld and invokes /domain.tld/www