Theming Drupal Usernames

I'm working on a new project right now where I had to create a bunch of user accounts on behalf of users. To keep things really easy for (what I think might be) a non-technical crowd I decided to use email addresses for usernames. Great! Except I don't really want to show email addresses all over the Web site where people names ought to be. The function theme_username() fixed up the "submitted by" text, but I wanted more than that. I wanted to change the navigation block and the user profile page as well. Here's how I did it in Drupal 6.

Caveat: usernames in Drupal have to be unique. With this "hack" multiple users can be identified by the same display name. This might not be appropriate for your site. Use this snippet with great caution and understanding that not all Laura Thomases and Christopher Moloneys are created equally.

Configuration

1. Install the profile module that comes with Drupal core.
2. Go to admin/user/profile to configure the user profiles.
3. To the profile, add a "single-line textfield" for "display name." (I actually used Given Names, and Family Name to allow me to sort by first or last name later if I want to.) Remember the machine-readable name. Make this field visible in the registration form, and make the values "required."
4. Add a "list selection" that will allow people to choose if they want to show their "username" or "display name." Remember the machine-readable name.
5. In the permissions section, allow users to change their own usernames.

Theme
Once you have the configuration set up, you can begin altering the displayed name in your theme. There are three functions I had to create and/or modify in my template.php file: THEMENAME_preprocess_page, THEMENAME_preprocess_block, THEMENAME_username. In each of these functions I did a little test to see if the display name toggle was set to show "username" or "display name." I also quickly checked to see if there was an @ character in the username (with the assumption that an @ symbol meant the account holder hadn't logged in and changed their username). Although I did have the name swap in THEMENAME_preprocess_user_profile as well, it doesn't appear to be necessary when each of _page, _block and _username are all themed.

THEMENAME_preprocess_page: Fixes the name that appears on the user's profile page (display title and "head" title which appears at the very top of the browser window).
// Map the First and Last name onto the username if requested,
// or if the username appears to be an email address.

$user = user_load($vars['user']->uid);
if ( ($user->profile_displayname == "Given names" || strpos("@", $vars['user']->name) > 0)
&& $vars['title'] == $user->name):
$name = $user->profile_first . " " . $user->profile_last;
$vars['head_title'] = str_replace($vars['title'], $name, $vars['head_title']);
$vars['title'] = $name;
endif;


THEMENAME_preprocess_block: Fixes the navigation block to show the display name instead of the username
// You don't really need to test all blocks, just those related to the 'user' module
$block = $vars['block'];
    if ($block->module == "user"):
$user = user_load($vars['user']->uid);
if ($block->subject == $user->name) :
$block->subject = $user->profile_first . " " . $user->profile_last;
endif;
endif;

THEMENAME_username: Fixes the name in the "submitted by" text in nodes.
// Copy the exactly the whole function from the API documentation
// paste it exactly into your theme's template.php file
// and add the following to the BEGINNING of the function

$user = user_load($object->uid);
if ($user->profile_displayname == "Given names" || strpos("@", $user->name) > 0 ):
$object->name = $user->profile_first . " " . $user->profile_last;
endif;

(Note: this works in Drupal 6.x, it will not work in previous versions of Drupal.)