<?php
/*
Plugin Name: Insensitive
Plugin URI: http://n0tablog.wordpress.com/my-wordpress-plug-ins/insensitive/
Description: Wordpress usernames are case sensitive. Many people on the Internet are used to case-insensitive passwords, where "Caroline" and "caroline" refer to the same account. Insencitive plug-in takes care of it. Sensibly.
Version: 1.0
Author: Andrey Abramov
Author URI:  http://n0tablog.wordpress.com/
*/
/*  Copyright 2007  Andrey Abramov

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/*
 This plugin depends (among other things) on get_userdatabylogin being case-insensitive.
 Why is get_userdatabylogin  case-insensitive and how does Wordpress distinguish
 between "John" and "john"? - Beats me!

*/

// This plugin depends on overriding the pluggable function function get_userdatabylogin().
// So, it will conflict with any other plugin that insists on overriding the same function.
// Not that I know any.


function AA_insensitive($username,$raw_username,$strict) {

  $username = strtolower($username);

	return $username;
}

function AA_validate_username($valid,$username) {

	$username = strtolower($username);

// From here on this function mimics the original validate_username.
// This is necessary due to the inconsistencies in applying sanitize_user
// in wp-register.php and admin-functions.php
// For the same reason this filter is set with the top priority in add_filter below.

	$name = sanitize_user($username, true);
	$valid = true;

	if ( $name != $username )
		$valid = false;

	return $valid;
}


add_filter('sanitize_user', 'AA_insensitive',10,3);
add_filter('validate_username', 'AA_validate_username',10,2);

// Since wp_login checks
//    if ( ($already_md5 && md5($login->user_pass) == $password) || ($login->user_login == $username && $login->user_pass == md5($password)) )
// where  $login->user_login comes from  get_userdatabylogin()
// We replace the original pluggable function get_userdatabylogin
// with the following,
// where the only difference is my liberal use of sanitize_user()

if ( !function_exists('get_userdatabylogin') ) :
function get_userdatabylogin($user_login) {
	global $wpdb;
// AA this sanitize_user came from the original source
	$user_login = sanitize_user( $user_login );

	if ( empty( $user_login ) )
		return false;

	$userdata = wp_cache_get($user_login, 'userlogins');

	if ( $userdata ) {
//AA next line is new
    $userdata->user_login = sanitize_user( $userdata->user_login );
		return $userdata; }

	if ( !$user = $wpdb->get_row("SELECT * FROM $wpdb->users WHERE user_login = '$user_login'") )
		return false;
//AA next line is new
$user->user_login = sanitize_user( $user->user_login );
	$wpdb->hide_errors();
	$metavalues = $wpdb->get_results("SELECT meta_key, meta_value FROM $wpdb->usermeta WHERE user_id = '$user->ID'");
	$wpdb->show_errors();

	if ($metavalues) {
		foreach ( $metavalues as $meta ) {
			$value = maybe_unserialize($meta->meta_value);
			$user->{$meta->meta_key} = $value;

			// We need to set user_level from meta, not row
			if ( $wpdb->prefix . 'user_level' == $meta->meta_key )
				$user->user_level = $meta->meta_value;
		}
	}

	// For backwards compat.
	if ( isset($user->first_name) )
		$user->user_firstname = $user->first_name;
	if ( isset($user->last_name) )
		$user->user_lastname = $user->last_name;
	if ( isset($user->description) )
		$user->user_description = $user->description;

	wp_cache_add($user->ID, $user, 'users');
	wp_cache_add($user->user_login, $user, 'userlogins');

	return $user;

}
endif;

?>