Codeigniter .htaccess - force HTTPS

.htaccess

RewriteEngine On

# start force http www (optional)
RewriteCond %{HTTP_HOST} !=localhost
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [R=301,L]
# end force http www (optional)

# start force https
RewriteCond %{HTTP_HOST} !=localhost
RewriteCond %{HTTPS} !on [NC]
RewriteRule ^(.*)$ https://%{HTTP_HOST}/$1 [R=301,L]
# end force https

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php/$1 [L]