RewriteEngine on
RewriteCond %{REQUEST_URI} !/$
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^(.*) %{REQUEST_URI}/ [R=301,L]
RewriteCond %{REQUEST_FILENAME} -d [NC]
RewriteCond %{REQUEST_FILENAME} !-f [NC]
RewriteRule ^(.*)$ index.php?%{QUERY_STRING}&directory=$1&modrewrite=1 [QSA]