.htaccess mod_rewrite help!

Question

Just want to say if anyone can help me it would be most appreciated, I have been looking for hours trying all different things with no luck.

I basically want to hide the .php extension and add a trailing slash which I've managed to do.

But if someone goes to file.php it still loads and does not redirect to /file/ also /file// still loads and also 404 errors stopped working and go into a loop. like .php.php.phphphp

RewriteEngine On

RewriteRule ^(.*)/$ /$1.php [L]


RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_URI} !(.*)/$
RewriteRule ^(.*)$ http://www.parkat.co.uk/$1/ [R=301,L]