I'm ready to use the subdirectory format for my multilingual website.
My first question is: 
For SEO, have I to translate the page name in the url or it is useless?
Example:

```
- Same filename
site.com/fr/login
site.com/en/login

```

OR

```
- Different filename
site.com/fr/connexion
site.com/en/login

```

Then, when user is on site.com: Should I redirect him to `site.com/en` and `site.com/fr` depending user's IP? Or have I to set a default local, and have my url like `site.com/page` and `site.com/fr/page` 

Finally, what is the best way to get the local from user's current URL?
Parsing url to get /fr or /en, or add a GET parameter in url with lang=fr (hidden with htaccess)

Thanks :)