user.module

<?php
/**
 * @file
 * Enables the user registration and login system.
 */

/**
 * Maximum length of username text field.
 */
define('USERNAME_MAX_LENGTH', 60);

/**
 * Users can login with username only.
 */
define('USER_LOGIN_USERNAME_ONLY', 'username_only');

/**
 * Users can login with email address only.
 */
define('USER_LOGIN_EMAIL_ONLY', 'email_only');

/**
 * Users can login using either username or email address.
 */
define('USER_LOGIN_USERNAME_OR_EMAIL', 'username_or_email');

/**
 * Only administrators can create user accounts.
 */
define('USER_REGISTER_ADMINISTRATORS_ONLY', 'admin_only');

/**
 * Visitors can create their own accounts.
 */
define('USER_REGISTER_VISITORS', 'visitors');

/**
 * Visitors can create accounts, but they don't become active without
 * administrative approval.
 */
define('USER_REGISTER_VISITORS_ADMINISTRATIVE_APPROVAL', 'visitors_admin_approval');

/**
 * Password strength modifier to encourage longer passwords.
 */
define('USER_PASSWORD_STRENGTH_MODIFIER', 0.7);

/**
 * Password strength levels: weak, fair, good and strong.
 */
define('USER_PASSWORD_STRENGTH_WEAK', 0);
define('USER_PASSWORD_STRENGTH_FAIR', 50);
define('USER_PASSWORD_STRENGTH_GOOD', 70);
define('USER_PASSWORD_STRENGTH_STRONG', 90);

/**
 * Invokes a user hook in every module.
 *
 * We cannot use module_invoke() for this, because the arguments need to
 * be passed by reference.
 *
 * @param $type
 *   A text string that controls which user hook to invoke. Valid choices are:
 *   - login: Invokes hook_user_login().
 * @param $edit
 *   An associative array variable containing form values to be passed
 *   as the first parameter of the hook function.
 * @param $account
 *   The user account object to be passed as the second parameter of the hook
 *   function.
 */
function user_module_invoke($type, &$edit, $account) {
  foreach (module_implements('user_' . $type) as $module) {
    $function = $module . '_user_' . $type;
    $function($edit, $account);
  }
}

/**
 * Implements hook_theme().
 */
function user_theme() {
  $base = array(
    'file' => 'user.theme.inc',
  );

  return array(
    'user_picture' => array(
      'variables' => array('account' => NULL),
      'template' => 'templates/user-picture',
    ) + $base,
    'user_profile' => array(
      'render element' => 'elements',
      'template' => 'templates/user-profile',
    ) + $base,
    'user_list' => array(
      'variables' => array('users' => NULL, 'title' => NULL),
    ) + $base,
    'user_admin_permissions' => array(
      'render element' => 'form',
    ) + $base,
    'user_admin_roles' => array(
      'render element' => 'form',
    ) + $base,
    'user_permission_description' => array(
      'variables' => array('permission_item' => NULL),
    ) + $base,
    'user_signature' => array(
      'variables' => array('signature' => NULL),
    ) + $base,
    'username' => array(
      'variables' => array('account' => NULL),
    ) + $base,
  );
}

/**
 * Implements hook_entity_info().
 */
function user_entity_info() {
  $entity_info = array(
    'user' => array(
      'label' => t('User account'),
      'bundle label' => t('Type'),
      'controller class' => 'UserStorageController',
      'base table' => 'users',
      'fieldable' => TRUE,
      'redirect support' => TRUE,
      'entity class' => 'User',
      'entity keys' => array(
        'id' => 'uid',
      ),
      'bundles' => array(
        'user' => array(
          'label' => t('User account'),
          'admin' => array(
            'path' => 'admin/config/people/manage',
            'access arguments' => array('administer account settings'),
          ),
        ),
      ),
      'view modes' => array(
        'full' => array(
          'label' => t('User account'),
          'custom settings' => FALSE,
        ),
        'token' => array(
          'label' => t('Tokens'),
          'custom settings' => FALSE,
        ),
      ),
    ),
  );

  // If the cache table has been created, then enable entity caching on nodes.
  if (db_table_exists('cache_entity_user')) {
    $entity_info['user']['entity cache'] = TRUE;
    $entity_info['user']['field cache'] = FALSE;
  }

  return $entity_info;
}

/**
 * Implements hook_layout_context_info().
 */
function user_layout_context_info() {
  $info['user'] = array(
    'title' => t('User account'),
    // Define the class which is used to handle this context.
    'class' => 'EntityLayoutContext',
    // Define menu paths where the user ID is a "known" context.
    'menu paths' => array(
      'user/%user',
      'user/%user/view',
      'user/%user/edit',
    ),
    // Given the menu paths defined above, identify the part of the path that
    // is needed to generate this context.
    'path placeholder' => '%user',
    // Given an argument, define the callback that will be responsible for
    // loading the main context data.
    'load callback' => 'user_load',
  );
  return $info;
}

/**
 * Implements hook_field_info_alter().
 */
function user_field_info_alter(&$info) {
  // Add the 'user_register_form' instance setting to all field types.
  foreach ($info as $field_type => &$field_type_info) {
    $field_type_info += array('instance_settings' => array());
    $field_type_info['instance_settings'] += array(
      'user_register_form' => FALSE,
    );
  }
}

/**
 * Implements hook_field_extra_fields().
 */
function user_field_extra_fields() {
  $return['user']['user'] = array(
    'form' => array(
      'account' => array(
        'label' => t('User name and password'),
        'description' => t('User module account form elements.'),
        'weight' => -10,
      ),
      'account_settings' => array(
        'label' => t('Account status and user roles'),
        'description' => t('User module account settings form elements.'),
        'weight' => 1,
      ),
      'timezone' => array(
        'label' => t('Timezone'),
        'description' => t('User module timezone form element.'),
        'weight' => 6,
      ),
    ),
    'display' => array(
      'member_for' => array(
        'label' => t('Member for'),
        'description' => t('User module \'member for\' view element.'),
        'weight' => 5,
      ),
    ),
  );

  return $return;
}

/**
 * Load multiple users based on certain conditions.
 *
 * This function should be used whenever you need to load more than one user
 * from the database. Users are loaded into memory and will not require
 * database access if loaded again during the same page request.
 *
 * @param $uids
 *   An array of user IDs.
 * @param $conditions
 *   (deprecated) An associative array of conditions on the {users}
 *   table, where the keys are the database fields and the values are the
 *   values those fields must have. Instead, it is preferable to use
 *   EntityFieldQuery to retrieve a list of entity IDs loadable by
 *   this function.
 * @param $reset
 *   A boolean indicating that the internal cache should be reset. Use this if
 *   loading a user object which has been altered during the page request.
 *
 * @return
 *   An array of user objects, indexed by uid.
 *
 * @see entity_load()
 * @see user_load()
 * @see user_load_by_mail()
 * @see user_load_by_name()
 * @see EntityFieldQuery
 *
 * @todo Remove $conditions for consistency with other loaders.
 */
function user_load_multiple($uids = array(), $conditions = array(), $reset = FALSE) {
  return entity_load('user', $uids, $conditions, $reset);
}

/**
 * Loads a user object.
 *
 * Backdrop has a global $user object, which represents the currently-logged-in
 * user. So to avoid confusion and to avoid clobbering the global $user object,
 * it is a good idea to assign the result of this function to a different local
 * variable, generally $account. If you actually do want to act as the user you
 * are loading, it is essential to call backdrop_save_session(FALSE); first.
 * See
 * @link http://drupal.org/node/218104 Safely impersonating another user @endlink
 * for more information.
 *
 * @param $uid
 *   Integer specifying the user ID to load.
 * @param $reset
 *   TRUE to reset the internal cache and load from the database; FALSE
 *   (default) to load from the internal cache, if set.
 *
 * @return
 *   A fully-loaded user object upon successful user load, or FALSE if the user
 *   cannot be loaded.
 *
 * @see user_load_multiple()
 */
function user_load($uid, $reset = FALSE) {
  $users = user_load_multiple(array($uid), array(), $reset);
  return reset($users);
}

/**
 * Fetch a user object by email address.
 *
 * @param $mail
 *   String with the account's email address.
 * @return
 *   A fully-loaded $user object upon successful user load or FALSE if user
 *   cannot be loaded.
 *
 * @see user_load_multiple()
 */
function user_load_by_mail($mail) {
  $users = user_load_multiple(array(), array('mail' => $mail));
  return reset($users);
}

/**
 * Fetch a user object by account name.
 *
 * @param $name
 *   String with the account's user name.
 * @return
 *   A fully-loaded $user object upon successful user load or FALSE if user
 *   cannot be loaded.
 *
 * @see user_load_multiple()
 */
function user_load_by_name($name) {
  $users = user_load_multiple(array(), array('name' => $name));
  return reset($users);
}

/**
 * Save a new or updated user.
 *
 * @param User $account
 *   The user entity object to add or modify.
 * @return int
 *   Either SAVED_NEW or SAVED_UPDATED depending on the operation performed.
 *
 * @see entity_create()
 * @see user_load()
 */
function user_save($account) {
  return $account->save();
}

/**
 * Element validate handler for the password field.
 *
 * Set a default value if one-time login link goes out,
 * set a form error if not and password value is empty.
 */
function user_pass_required_validate($element, &$form_state, $form) {
  $values = $form_state['values'];
  if ($values['notify'] == 1) {
    $form_state['values']['pass'] = user_password(22);
  }
  else {
    if (empty($values['pass']) && $values['pass'] !== '0') {
      $message = t('!name field is required.', array('!name' => $element['#title']));
      form_set_error('pass', $message);
    }
  }
}

/**
 * Verify the syntax of the given name.
 */
function user_validate_name($name) {
  if (!$name) {
    return t('You must enter a username.');
  }
  if (substr($name, 0, 1) == ' ') {
    return t('The username cannot begin with a space.');
  }
  if (substr($name, -1) == ' ') {
    return t('The username cannot end with a space.');
  }
  if (strpos($name, '  ') !== FALSE) {
    return t('The username cannot contain multiple spaces in a row.');
  }
  if (preg_match('/[^\x{80}-\x{F7} a-z0-9@+_.\'-]/i', $name)) {
    return t('The username contains an illegal character.');
  }
  // cspell:disable
  if (preg_match('/[\x{80}-\x{A0}' .        // Non-printable ISO-8859-1 + NBSP.
                  '\x{AD}' .                // Soft-hyphen.
                  '\x{2000}-\x{200F}' .     // Various space characters.
                  '\x{2028}-\x{202F}' .     // Bidirectional text overrides.
                  '\x{205F}-\x{206F}' .     // Various text hinting characters.
                  '\x{FEFF}' .              // Byte order mark.
                  '\x{FF01}-\x{FF60}' .     // Full-width latin.
                  '\x{FFF9}-\x{FFFD}' .     // Replacement characters.
                  '\x{0}-\x{1F}]/u',        // NULL byte and control characters.
                  // cspell:enable
                  $name)) {
    return t('The username contains an illegal character.');
  }
  if (backdrop_strlen($name) > USERNAME_MAX_LENGTH) {
    return t('The username %name is too long: it must be %max characters or less.', array('%name' => $name, '%max' => USERNAME_MAX_LENGTH));
  }
}

/**
 * Validates an image uploaded by a user.
 *
 * @see user_account_form()
 */
function user_validate_picture(&$form, &$form_state) {
  $site_config = config('system.core');
  // If required, validate the uploaded picture.
  $validators = array(
    'file_validate_is_image' => array(),
    'file_validate_image_orientation' => array(TRUE),
    'file_validate_image_resolution' => array($site_config->get('user_picture_dimensions')),
    'file_validate_size' => array((int) $site_config->get('user_picture_file_size') * 1024),
  );

  // Save the file as a temporary file.
  $file = file_save_upload('picture_upload', $validators);
  if ($file === FALSE) {
    form_set_error('picture_upload', t("Failed to upload the picture image; the %directory directory doesn't exist or is not writable.", array('%directory' => $site_config->get('user_picture_path'))));
  }
  elseif ($file !== NULL) {
    $form_state['values']['picture_upload'] = $file;
  }
}

/**
 * Generate a random alphanumeric password.
 */
function user_password($length = 10) {
  // This variable contains the list of allowable characters for the
  // password. Note that the number 0 and the letter 'O' have been
  // removed to avoid confusion between the two. The same is true
  // of 'I', 1, and 'l'.
  // cspell:disable-next-line
  $allowable_characters = 'abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789';

  // Zero-based count of characters in the allowable list:
  $len = strlen($allowable_characters) - 1;

  // Declare the password as a blank string.
  $pass = '';

  // Loop the number of times specified by $length.
  for ($i = 0; $i < $length; $i++) {
    do {
      // Find a secure random number within the range needed.
      $index = ord(backdrop_random_bytes(1));
    } while ($index > $len);

    // Each iteration, pick a random character from the
    // allowable string and append it to the password:
    $pass .= $allowable_characters[$index];
  }

  return $pass;
}

/**
 * Checks if a user role has a permission.
 *
 * @param string $role_name
 *   The role machine name.
 * @param string $permission_name
 *   The permission to check.
 *
 * @return bool
 *   TRUE if the role has the permission, FALSE if it does not have the
 *   permission.
 *
 * @since 1.26.0 Function added
 */
function user_role_has_permission($role_name, $permission_name) {
  $role = user_role_load($role_name);
  return $role ? in_array($permission_name, $role->permissions) : FALSE;
}

/**
 * Determine the permissions for one or more roles.
 *
 * @param $role_names
 *   An unindexed array of role names, such as those in $user->roles.
 *
 * @return
 *   An array of permission strings for all the given role names.
 */
function user_role_permissions($role_names = array()) {
  $all_roles = user_roles(FALSE, NULL, TRUE);
  $role_permissions = array();
  foreach ($role_names as $role_name) {
    if (isset($all_roles[$role_name])) {
      foreach ($all_roles[$role_name]->permissions as $permission) {
        if (!in_array($permission, $role_permissions)) {
          $role_permissions[] = $permission;
        }
      }
    }
  }

  return $role_permissions;
}

/**
 * Determine whether the user has a given privilege.
 *
 * @param $string
 *   The permission, such as "administer nodes", being checked for.
 * @param $account
 *   (optional) The account to check, if not given use currently logged in user.
 *
 * @return
 *   Boolean TRUE if the user has the requested permission.
 *
 * All permission checks in Backdrop should go through this function. This
 * way, we guarantee consistent behavior, and ensure that the superuser
 * can perform all actions.
 */
function user_access($permission_name, $account = NULL) {
  global $user;

  if (!isset($account)) {
    $account = $user;
  }

  // User #1 has all privileges:
  if ($account->uid == 1) {
    return TRUE;
  }

  // To reduce the number of SQL queries, we cache the user's permissions
  // in a static variable.
  // Use the advanced backdrop_static() pattern, since this is called very often.
  static $backdrop_static_fast;
  if (!isset($backdrop_static_fast)) {
    $backdrop_static_fast['perm'] = &backdrop_static(__FUNCTION__);
  }
  $perm = &$backdrop_static_fast['perm'];
  if (!isset($perm[$account->uid])) {
    $perm[$account->uid] = user_role_permissions($account->roles);
  }

  return in_array($permission_name, $perm[$account->uid]);
}

/**
 * Checks for usernames blocked by user administration.
 *
 * @param $name
 *   A string containing a name of the user.
 *
 * @return
 *   Object with property 'name' (the user name), if the user is blocked;
 *   FALSE if the user is not blocked.
 */
function user_is_blocked($name) {
  return db_select('users')
    ->fields('users', array('name'))
    ->condition('name', db_like($name), 'LIKE')
    ->condition('status', 0)
    ->execute()->fetchObject();
}

/**
 * Checks if a user has a role.
 *
 * @param string $role_name
 *   A string representing the role name.
 * @param User $account
 *   (optional) A user account. Defaults to the current user.
 *
 * @return bool
 *   TRUE or FALSE.
 *
 * @since 1.14.0 First parameter changed from $rid to $role_name.
 */
function user_has_role($role_name, User $account = NULL) {
  if (!$account) {
    $account = $GLOBALS['user'];
  }

  return in_array($role_name, $account->roles);
}

/**
 * Implements hook_permission().
 */
function user_permission() {
  return array(
    'administer permissions' =>  array(
      'title' => t('Administer permissions'),
      'restrict access' => TRUE,
      'warning' => t('Grant any permission to any user role.'),
    ),
    'administer users' => array(
      'title' => t('Administer user accounts'),
      'restrict access' => TRUE,
      'warning' => t('Create, edit and delete user accounts.'),
    ),
    'assign roles' => array(
      'title' => t('Assign user roles'),
      'restrict access' => TRUE,
      'warning' => t('Assign any user role to any user account.'),
    ),
    'administer account settings' => array(
      'title' => t('Administer user account settings'),
      'description' => t('Manage settings that apply to all user accounts.'),
      'restrict access' => TRUE,
      'warning' => t('Change the way user account registrations work, potentially avoiding administrator approval.'),
    ),
    'access user profiles' => array(
      'title' => t('View user profiles'),
    ),
    'change own username' => array(
      'title' => t('Change own username'),
    ),
    'cancel account' => array(
      'title' => t('Cancel own user account'),
      'description' => t('Note: content may be kept, unpublished, deleted or transferred to the %anonymous-name user depending on the configured <a href="@user-settings-url">user settings</a>.', array('%anonymous-name' => config_get_translated('system.core', 'anonymous'), '@user-settings-url' => url('admin/config/people/settings'))),
    ),
    'select account cancellation method' => array(
      'title' => t('Select method for cancelling own account'),
      'restrict access' => TRUE,
      'warning' => t('Allows people to choose to permanently delete their user account and all content created by them (potential for irreversible data loss).'),
    ),
  );
}

/**
 * Implements hook_config_info().
 */
function user_config_info() {
  $prefixes['user.flood'] = array(
    'label' => t('User flood'),
    'group' => t('Configuration'),
  );
  $prefixes['user.mail'] = array(
    'label' => t('User email templates'),
    'group' => t('Configuration'),
  );
  $prefixes['user.role'] = array(
    'name_key' => 'name',
    'label_key' => 'label',
    'group' => t('User roles'),
  );
  return $prefixes;
}

/**
 * Implements hook_views_api().
 */
function user_views_api() {
  return array(
    'api' => '3.0',
    'path' => backdrop_get_path('module', 'user') . '/views',
  );
}

/**
 * Implements hook_file_download().
 *
 * Ensure that user pictures (avatars) are always downloadable.
 */
function user_file_download($uri) {
  if (strpos(file_uri_target($uri), config_get('system.core', 'user_picture_path') . '/picture-') === 0) {
    $info = image_get_info($uri);
    return array('Content-Type' => $info['mime_type']);
  }
}

/**
 * Implements hook_file_move().
 */
function user_file_move(File $file, File $source) {
  // If a user's picture is replaced with a new one, update the record in
  // the users table.
  if (isset($file->fid) && isset($source->fid) && $file->fid != $source->fid) {
    db_update('users')
      ->fields(array(
        'picture' => $file->fid,
      ))
      ->condition('picture', $source->fid)
      ->execute();
  }
}

/**
 * Implements hook_file_predelete().
 */
function user_file_predelete(File $file) {
  // Remove any references to the file.
  db_update('users')
    ->fields(array('picture' => 0))
    ->condition('picture', $file->fid)
    ->execute();
}

/**
 * Implements hook_search_info().
 */
function user_search_info() {
  return array(
    'title' => 'User accounts',
  );
}

/**
 * Implements hook_search_access().
 */
function user_search_access() {
  return user_access('access user profiles');
}

/**
 * Implements hook_search_execute().
 */
function user_search_execute($keys = NULL, $conditions = NULL) {
  $find = array();
  // Escape for LIKE matching.
  $keys = db_like($keys);
  // Replace wildcards with MySQL wildcards.
  $keys = preg_replace('!\*+!', '%', $keys);
  $query = db_select('users')->extend('PagerDefault');
  $query->fields('users', array('uid'));
  if (user_access('administer users')) {
    // Administrators can also search in the otherwise private email field,
    // and they don't need to be restricted to only active users.
    $query->fields('users', array('mail'));
    $query->condition(db_or()->
      condition('name', '%' . $keys . '%', 'LIKE')->
      condition('mail', '%' . $keys . '%', 'LIKE'));
  }
  else {
    // Regular users can only search via usernames, and we do not show them
    // blocked accounts.
    $query->condition('name', '%' . $keys . '%', 'LIKE')
      ->condition('status', 1);
  }
  $uids = $query
    ->limit(15)
    ->execute()
    ->fetchCol();
  $accounts = user_load_multiple($uids);

  $results = array();
  foreach ($accounts as $account) {
    $result = array(
      'title' => user_format_name($account),
      'link' => url('user/' . $account->uid, array('absolute' => TRUE)),
    );
    if (user_access('administer users')) {
      $result['title'] .= ' (' . $account->mail . ')';
    }
    $results[] = $result;
  }

  return $results;
}

/**
 * Implements hook_user_view().
 */
function user_user_view($account) {
  $account->content['user_picture'] = array(
    '#markup' => theme('user_picture', array('account' => $account)),
    '#weight' => -10,
  );
  $account->content['member_for'] = array(
    '#type' => 'item',
    '#title' => t('Member for'),
    '#markup' => format_interval(REQUEST_TIME - $account->created),
    '#weight' => 5,
  );
}

/**
 * Helper function to add default user account fields to user registration and edit form.
 *
 * @see user_account_form_validate()
 * @see user_validate_current_pass()
 * @see user_validate_picture()
 * @see user_validate_mail()
 * @see user_password_policy_validate()
 */
function user_account_form(&$form, &$form_state) {
  global $user;
  $site_config = config('system.core');

  $account = $form['#user'];
  $register = ($form['#user']->uid > 0 ? FALSE : TRUE);

  $admin_users = user_access('administer users');
  $admin_roles = user_access('assign roles');

  $form['#validate'][] = 'user_account_form_validate';
  module_load_include('password.inc', 'user', 'user');
  $reject_weak = user_password_reject_weak($user->name);

  if ($reject_weak) {
    $form['#validate'][] = 'user_password_policy_validate';
  }

  // Account information.
  $form['account'] = array(
    '#type'   => 'container',
    '#weight' => -10,
  );
  // Only show name field on registration form or user can change own username.
  $form['account']['name'] = array(
    '#type' => 'textfield',
    '#title' => t('Username'),
    '#maxlength' => USERNAME_MAX_LENGTH,
    '#description' => t('Spaces are allowed; punctuation is not allowed except for periods, hyphens, apostrophes, and underscores.'),
    '#required' => TRUE,
    '#attributes' => array(
      'class' => array('username'),
      // Add attributes to field to prevent spell-jacking and unwanted
      // automatic changes caused by the browser.
      'autocapitalize' => 'none',
      'autocorrect' => 'off',
      'spellcheck' => 'false',
    ),
    '#default_value' => (!$register ? $account->name : ''),
    '#access' => ($register || ($user->uid == $account->uid && user_access('change own username')) || $admin_users),
    '#weight' => -10,
  );
  // Autofocus the username field (on the registration form only).
  if ($register) {
    $form['account']['name']['#attributes']['autofocus'] = 'autofocus';
  }

  $form['account']['mail'] = array(
    '#type' => 'email',
    '#title' => t('Email address'),
    '#description' => t('A valid email address. All emails from the system will be sent to this address. The email address is not made public and will only be used if you wish to receive a new password or wish to receive certain news or notifications by email.'),
    '#required' => TRUE,
    '#default_value' => (!$register ? $account->mail : ''),
    '#attributes' => array(
      // Add attributes to field to prevent spell-jacking and unwanted
      // automatic changes caused by the browser.
      'autocapitalize' => 'none',
      'autocorrect' => 'off',
      'spellcheck' => 'false',
    ),
  );

  // Display password field only for existing users or when user is allowed to
  // assign a password during registration.
  if (!$register) {
    $form['account']['pass'] = array(
      '#title' => t('New password'),
      '#type' => 'password',
      '#password_toggle' => TRUE,
      '#password_strength' => TRUE,
    );
    // To skip the current password field, the user must have logged in via a
    // one-time link and have the token in the URL. Store this in $form_state
    // so it persists even on subsequent Ajax requests.
    if (!isset($form_state['user_pass_reset'])) {
      $form_state['user_pass_reset'] = isset($_SESSION['pass_reset_' . $account->uid]) && isset($_GET['pass-reset-token']) && ($_GET['pass-reset-token'] == $_SESSION['pass_reset_' . $account->uid]);
    }
    $protected_values = array();
    $current_pass_description = '';
    // The user may only change their own password without their current
    // password if they logged in via a one-time login link.
    if (!$form_state['user_pass_reset']) {
      $protected_values['mail'] = $form['account']['mail']['#title'];
      $protected_values['pass'] = t('Password');
      $request_new = l(t('Reset password'), 'user/password', array('attributes' => array('title' => t('Reset password via one-time login link.'))));
      $current_pass_description = t('Required if you want to change the %mail or %pass below. !request_new.', array('%mail' => $protected_values['mail'], '%pass' => $protected_values['pass'], '!request_new' => $request_new));
    }
    // The user must enter their current password to change to a new one.
    if ($user->uid == $account->uid) {
      $form['account']['current_pass_required_values'] = array(
        '#type' => 'value',
        '#value' => $protected_values,
      );
      $form['account']['current_pass'] = array(
        '#type' => 'password',
        '#title' => t('Current password'),
        '#access' => !empty($protected_values),
        '#description' => $current_pass_description,
        '#weight' => -5,
        '#password_toggle' => TRUE,
        // Do not let web browsers remember this password, since we are
        // trying to confirm that the person submitting the form actually
        // knows the current one.
        '#attributes' => array('autocomplete' => 'off'),
      );
      $form['#validate'][] = 'user_validate_current_pass';
    }
  }
  else {
    if (!$site_config->get('user_email_verification') && !$admin_users) {
      // Someone registers a new account and may set a password directly.
      $form['account']['pass'] = array(
        '#type' => 'password',
        '#title' => t('Password'),
        '#password_toggle' => TRUE,
        '#password_strength' => TRUE,
        '#required' => TRUE,
      );
    }
    if ($admin_users) {
      // An admin creates an account.
      $form['account']['notify'] = array(
        '#type' => 'checkbox',
        '#title' => t('Notify user of new account'),
        '#default_value' => 1,
        '#description' => t('The user will receive an email with a one-time login link which leads to a page where they can set their password.'),
      );
      $form['account']['pass'] = array(
        '#type' => 'password',
        '#title' => t('Password'),
        '#password_toggle' => TRUE,
        '#password_strength' => TRUE,
        '#required' => FALSE,
        '#element_validate' => array('user_pass_required_validate'),
        '#states' => array(
          'visible' => array(
            ':input[name="notify"]' => array('checked' => FALSE),
          ),
          'required' => array(
            ':input[name="notify"]' => array('checked' => FALSE),
          ),
        ),
      );
    }
  }

  $description = !$register && $user->uid == $account->uid ? t('The current password must be entered to set a new password.') : '';
  // If weak passwords are being rejected, append the list of password strength
  // criteria to the help text of the password field.
  if ($reject_weak) {
    $description .= !empty($description) ? '<br /><br />' : '';
    $description .= _user_password_policy_help();
  }
  $form['account']['pass']['#description'] = $description;

  $form['additional_settings'] = array(
    '#type' => 'vertical_tabs',
    '#weight' => 99,
    '#attached' => array(
      'js' => array(backdrop_get_path('module', 'user') . '/js/user.admin.js'),
    ),
  );

  $form['account_settings'] = array(
    '#type' => 'fieldset',
    '#title' => t('Account settings'),
    '#weight' => 1,
    '#access' => $admin_users || $admin_roles,
    '#group' => 'additional_settings',
  );

  if ($admin_users) {
    $status = isset($account->status) ? $account->status : 1;
  }
  else {
    $status = $register ? $site_config->get('user_register') == USER_REGISTER_VISITORS : $account->status;
  }
  $form['account_settings']['status'] = array(
    '#type' => 'radios',
    '#title' => t('Status'),
    '#default_value' => $status,
    '#options' => array(t('Blocked'), t('Active')),
    '#access' => $admin_users,
  );

  $roles = user_roles(TRUE, NULL, TRUE);
  $form['account_settings']['roles'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Roles'),
    '#default_value' => (!$register && isset($account->roles) ? $account->roles : array()),
    '#options' => array(),
    '#access' => count($roles) && $admin_roles,
  );
  // Lock the authenticated role, which cannot be removed.
  $form['account_settings']['roles'][BACKDROP_AUTHENTICATED_ROLE] = array(
    '#disabled' => TRUE,
    '#value' => 'authenticated',
  );
  // Add each role as a checkbox option with a description.
  foreach ($roles as $role_name => $role) {
    $form['account_settings']['roles']['#options'][$role_name] = $role->label;
    if (strlen($role->description)) {
      $form['account_settings']['roles'][$role_name]['#description'] = filter_xss_admin($role->description);
    }
  }

  $form['personalization'] = array(
    '#type' => 'fieldset',
    '#title' => t('Personalization'),
    '#weight' => 2,
    '#access' => (!$register && ($site_config->get('user_signatures') || $site_config->get('user_pictures'))),
    '#group' => 'additional_settings',
  );
  // Signature.
  if ($site_config->get('user_signatures')) {
    $form['personalization']['signature'] = array(
      '#type' => 'text_format',
      '#title' => t('Signature'),
      '#default_value' => isset($account->signature) ? $account->signature : '',
      '#description' => t('Your signature will be publicly displayed at the end of your comments.'),
      '#format' => isset($account->signature_format) ? $account->signature_format : NULL,
    );
  }
  // Picture/avatar.
  if ($site_config->get('user_pictures')) {
    $form['personalization']['picture'] = array(
      '#type' => 'value',
      '#value' => isset($account->picture) ? $account->picture : NULL,
    );
    $form['personalization']['picture_current'] = array(
      '#markup' => theme('user_picture', array('account' => $account)),
    );
    $form['personalization']['picture_delete'] = array(
      '#type' => 'checkbox',
      '#title' => t('Delete picture'),
      '#access' => !empty($account->picture->fid),
      '#description' => t('Check this box to delete your current picture.'),
    );
    $form['personalization']['picture_upload'] = array(
      '#type' => 'file',
      '#title' => t('Upload picture'),
      '#size' => 48,
      '#description' => t('Your virtual face or picture. Pictures larger than @dimensions pixels will be scaled down.', array('@dimensions' => $site_config->get('user_picture_dimensions'))) . ' ' . filter_xss_admin($site_config->get('user_picture_guidelines')),
    );
    $form['#validate'][] = 'user_validate_picture';
  }

  $form['region_language'] = array(
    '#type' => 'fieldset',
    '#title' => t('Region and language'),
    '#weight' => 6,
    '#access' => (!$register && config_get('system.date', 'user_configurable_timezones')) || (module_exists('locale') && language_multilingual()),
    '#group' => 'additional_settings',
  );
  // See system_user_timezone() and locale_language_selector_form() for the form
  // items displayed here.
}

/**
 * Form validation handler for the current password on the user_account_form().
 *
 * @see user_account_form()
 */
function user_validate_current_pass(&$form, &$form_state) {
  $account = $form['#user'];
  foreach ($form_state['values']['current_pass_required_values'] as $key => $name) {
    // This validation only works for required textfields (like mail) or
    // form values like password_confirm that have their own validation
    // that prevent them from being empty if they are changed.
    if ((strlen(trim($form_state['values'][$key])) > 0) && ($form_state['values'][$key] != $account->$key)) {
      require_once BACKDROP_ROOT . '/' . settings_get('password_inc', 'core/includes/password.inc');
      $current_pass_failed = strlen(trim($form_state['values']['current_pass'])) === 0 || !user_check_password($form_state['values']['current_pass'], $account);
      if ($current_pass_failed) {
        form_set_error('current_pass', t("Your current password is missing or incorrect; it's required to change the %name.", array('%name' => $name)));
        form_set_error($key);
      }
      // We only need to check the password once.
      break;
    }
  }
}

/**
 * Form validation handler for user_account_form().
 *
 * @see user_account_form()
 */
function user_account_form_validate($form, &$form_state) {
  $account = $form['#user'];
  $mail = $form_state['values']['mail'];

  // Validate new or changing username.
  if (isset($form_state['values']['name'])) {
    $name = $form_state['values']['name'];
    if ($error = user_validate_name($name)) {
      form_set_error('name', $error);
    }
    // Cast the user ID as an integer. It might have been set to NULL, which
    // could lead to unexpected results.
    else {
      $name_taken = (bool) db_select('users')
        ->fields('users', array('uid'))
        ->condition('uid', (int) $account->uid, '<>')
        ->condition('name', db_like($name), 'LIKE')
        ->range(0, 1)
        ->execute()
        ->fetchField();

      if ($name_taken) {
        form_set_error('name', t('The name %name is already taken.', array('%name' => $name)));
      }
      // Check whether the user name provided is an email address. If so, make
      // sure it matches the mail value.
      if (config('system.core')->get('user_email_match') && (valid_email_address($name))) {
        if ($name !== $mail) {
          form_set_error('name', t('An email address was provided as a username, but does not match the account email address.'));
        }
      }
    }
  }

  if (!empty($mail)) {
    $mail_taken = (bool) db_select('users')
      ->fields('users', array('uid'))
      ->condition('uid', (int) $account->uid, '<>')
      ->condition('mail', db_like($mail), 'LIKE')
      ->range(0, 1)
      ->execute()
      ->fetchField();

    if ($mail_taken) {
      // Format error message dependent on whether the user is logged in or not.
      if ($GLOBALS['user']->uid) {
        form_set_error('mail', t('The email address %email is already taken.', array('%email' => $mail)));
      }
      else {
        form_set_error('mail', t('The email address %email is already registered. <a href="@password">Have you forgotten your password?</a>', array('%email' => $mail, '@password' => url('user/password'))));
      }
    }
  }

  // Make sure the signature isn't longer than the size of the database field.
  // Signatures are disabled by default, so make sure it exists first.
  if (isset($form_state['values']['signature'])) {
    // Move text format for user signature into 'signature_format'.
    $form_state['values']['signature_format'] = $form_state['values']['signature']['format'];
    // Move text value for user signature into 'signature'.
    $form_state['values']['signature'] = $form_state['values']['signature']['value'];

    $user_schema = backdrop_get_schema('users');
    if (backdrop_strlen($form_state['values']['signature']) > $user_schema['fields']['signature']['length']) {
      form_set_error('signature', t('The signature is too long: it must be %max characters or less.', array('%max' => $user_schema['fields']['signature']['length'])));
    }
  }
}

/**
 * Validation callback for password constraints.
 *
 * @see user_account_form()
 * @see user_pass_reset_form()
 */
function user_password_policy_validate($form, &$form_state) {
  $strength = 0;
  if (!array_key_exists('pass', $form_state['values'])) {
    // If mail verification is required, user registration forms don't have a
    // password field.
    return;
  }
  $password = trim($form_state['values']['pass']);

  if ($form['#form_id'] == 'user_profile_form' && strlen($password) == 0) {
    // On profile form and no new password has been set.
    return;
  }
  $config = config('system.core');
  $messages = array();
  if ($form['#form_id'] == 'user_pass_reset_form') {
    $account = $form['#account'];
    $username = $account->name;
    $email = $account->mail;
  }
  else {
    $username = $form_state['values']['name'];
    $email = $form_state['values']['mail'];
  }
  module_load_include('password.inc', 'user', 'user');
  // @todo add a hook so modules can override the strength.
  $strength = _user_password_evaluate_strength($password, $username, $email);

  if ($strength < $config->get('user_password_strength_threshold')) {
    form_set_error('complex_pass', t('The password is too weak. Please consider making your password longer or more complex: that it contains a number of lower- and uppercase letters, digits and punctuation.'));
  }

  if (backdrop_strtolower($password) == backdrop_strtolower($username)) {
    form_set_error('username_pass', t('The password cannot be the same as the username.'));
  }
  if (backdrop_strtolower($password) == backdrop_strtolower($email)) {
    form_set_error('email_pass', t('The password cannot be the same as the email.'));
  }
}

function user_login_block($form) {
  $site_config = config('system.core');
  $credentials = $site_config->get('user_login_method');

  $form['#action'] = url(current_path(), array('query' => backdrop_get_destination(), 'external' => FALSE));
  $form['#id'] = 'user-login-form';
  $form['#validate'] = user_login_default_validators();
  $form['#submit'][] = 'user_login_submit';
  $form['name'] = array(
    '#type' => 'textfield',
    '#title' => $credentials === USER_LOGIN_EMAIL_ONLY ? t('Email address') : ($credentials === USER_LOGIN_USERNAME_OR_EMAIL ? t('Username or email address') : t('Username')),
    '#maxlength' => $credentials === USER_LOGIN_USERNAME_ONLY ? USERNAME_MAX_LENGTH : EMAIL_MAX_LENGTH,
    '#size' => 15,
    '#required' => TRUE,
    '#weight' => 1,
    '#attributes' => array(
      // Add attributes to field to prevent spell-jacking and unwanted
      // automatic changes caused by the browser.
      'autocapitalize' => 'none',
      'autocorrect' => 'off',
      'spellcheck' => 'false',
    ),
  );

  $form['pass'] = array(
    '#type' => 'password',
    '#title' => t('Password'),
    '#size' => 15,
    '#required' => TRUE,
    '#weight' => 2,
    '#password_toggle' => TRUE,
  );
  $form['actions'] = array(
    '#type' => 'actions',
    '#weight' => 3,
  );
  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Log in'),
  );
  $items = array();
  if ($site_config->get('user_register') != USER_REGISTER_ADMINISTRATORS_ONLY) {
    $items[] = l(t('Create new account'), 'user/register', array('attributes' => array('title' => t('Create a new user account.'))));
  }
  $items[] = l(t('Reset password'), 'user/password', array('attributes' => array('title' => t('Reset password via one-time login link.'))));
  $form['links'] = array(
    '#theme' => 'item_list',
    '#items' => $items,
    '#weight' => 4,
  );
  return $form;
}

/**
 * Implements hook_block_info().
 */
function user_block_info() {
  $blocks = array();

  $blocks['login'] = array(
    'info' => t('User login'),
    'description' => t('The user login form if logged out.'),
  );

  return $blocks;
}

/**
 * Implements hook_block_view().
 */
function user_block_view($delta = '', $settings = array()) {
  global $user;
  $block = array();

  switch ($delta) {
    case 'login':
      // For usability's sake, avoid showing two login forms on one page.
      if (!$user->uid && !(arg(0) == 'user' && !is_numeric(arg(1)))) {

        $block['subject'] = t('User login');
        $block['content'] = backdrop_get_form('user_login_block');
      }
      return $block;
  }
}

/**
 * Implements hook_preprocess_block().
 */
function user_preprocess_block(&$variables) {
  if ($variables['block']->module == 'user') {
    switch ($variables['block']->delta) {
      case 'login':
        $variables['attributes']['role'] = 'form';
        break;
      case 'new':
        $variables['attributes']['role'] = 'complementary';
        break;
      case 'online':
        $variables['attributes']['role'] = 'complementary';
        break;
    }
  }
}

/**
 * Format a username.
 *
 * By default, the passed-in object's 'name' property is used if it exists, or
 * else, the site-defined value for the 'anonymous' variable. However, a module
 * may override this by implementing
 * hook_user_format_name_alter(&$name, $account).
 *
 * @see hook_user_format_name_alter()
 *
 * @param $account
 *   The account object for the user whose name is to be formatted.
 *
 * @return
 *   An unsanitized string with the username to display. The code receiving
 *   this result must ensure that check_plain() is called on it before it is
 *   printed to the page.
 */
function user_format_name($account) {
  $name = !empty($account->name) ? $account->name : config_get('system.core', 'anonymous');
  backdrop_alter('user_format_name', $name, $account);
  return $name;
}

/**
 * Determines if the current user is anonymous.
 *
 * @return bool
 *   TRUE if the user is anonymous, FALSE if the user is authenticated.
 */
function user_is_anonymous() {
  // Menu administrators can see items for anonymous when administering.
  return !$GLOBALS['user']->uid || !empty($GLOBALS['menu_admin']);
}

/**
 * Determines if the current user is logged in.
 *
 * @return bool
 *   TRUE if the user is logged in, FALSE if the user is anonymous.
 */
function user_is_logged_in() {
  return (bool) $GLOBALS['user']->uid;
}

/**
 * Determines if the current user has access to the user registration page.
 *
 * @return bool
 *   TRUE if the user is not already logged in and can register for an account.
 */
function user_register_access() {
  return user_is_anonymous() && config_get('system.core', 'user_register') !== USER_REGISTER_ADMINISTRATORS_ONLY;
}

/**
 * User view access callback.
 *
 * @param User|AnonymousUser|object $account
 *   Can either be a full user object or a $uid.
 *
 * @return bool
 *   Whether access is allowed or not.
 */
function user_view_access($account) {
  if ($account instanceof User) {
    return $account && $account->access('view');
  }
  return FALSE;
}

/**
 * Access callback for user account editing.
 */
function user_edit_access($account) {
  // Account for anonymous users, which are of class AnonymousUser.
  if ($account instanceof User) {
    /** @var User $account */
    return $account->access('update');
  }
  return FALSE;
}

/**
 * Menu access callback; limit access to account cancellation pages.
 *
 * Limit access to users with the 'cancel account' permission or administrative
 * users, and prevent the anonymous user from cancelling the account.
 */
function user_cancel_access($account) {
  // Account for anonymous users, which are of class AnonymousUser.
  if ($account instanceof User) {
    /** @var User $account */
    return $account->access('delete');
  }
  return FALSE;
}

/**
 * Implements hook_menu().
 */
function user_menu() {
  $items['user/autocomplete'] = array(
    'title' => 'User autocomplete',
    'page callback' => 'user_autocomplete',
    'delivery callback' => 'backdrop_json_deliver',
    'access callback' => 'user_access',
    'access arguments' => array('access user profiles'),
    'type' => MENU_CALLBACK,
    'file' => 'user.pages.inc',
  );

  // Registration and login pages.
  $items['user'] = array(
    'title' => 'User account',
    'title callback' => 'user_menu_title',
    'page callback' => 'user_page',
    'access callback' => TRUE,
    'file' => 'user.pages.inc',
    'weight' => -10,
    'menu_name' => 'user-menu',
  );

  $items['user/login'] = array(
    'title' => 'Log in',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_login'),
    'access callback' => 'user_is_anonymous',
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );

  $items['user/register'] = array(
    'title' => 'Create new account',
    'page callback' => 'user_register_page',
    'access callback' => 'user_register_access',
    'type' => MENU_LOCAL_TASK,
  );

  $items['user/password'] = array(
    'title' => 'Reset password',
    'page callback' => 'user_pass_page',
    'access callback' => TRUE,
    'type' => MENU_LOCAL_TASK,
    'file' => 'user.pages.inc',
  );

  $items['user/reset/%/%/%'] = array(
    'title' => 'Reset password',
    'page callback' => 'user_pass_reset',
    'page arguments' => array(2, 3, 4),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
    'file' => 'user.pages.inc',
  );

  $items['user/logout'] = array(
    'title' => 'Log out',
    'access callback' => 'user_is_logged_in',
    'page callback' => 'user_logout',
    'weight' => 10,
    'menu_name' => 'user-menu',
    'file' => 'user.pages.inc',
  );

  $items['admin/people/create'] = array(
    'title' => 'Add user account',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_register_form'),
    'access arguments' => array('administer users'),
    'type' => MENU_LOCAL_ACTION,
  );
  $items['admin/people/cancel'] = array(
    'title' => 'Cancel user accounts',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_multiple_cancel_confirm'),
    'access arguments' => array('administer users'),
    'file' => 'user.admin.inc',
    'type' => MENU_CALLBACK,
  );

  // Administration pages.
  $items['admin/config/people'] = array(
    'title' => 'User accounts',
    'icon' => 'users',
    'description' => 'Configure user accounts.',
    'weight' => -20,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
    'file path' => backdrop_get_path('module', 'system'),
  );
  $items['admin/config/people/settings'] = array(
    'title' => 'Account settings',
    'description' => 'Configure settings for user accounts.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_admin_settings'),
    'access arguments' => array('administer account settings'),
    'file' => 'user.admin.inc',
  );

  // Login settings.
  $items['admin/config/people/login'] = array(
    'title' => 'Login settings',
    'description' => 'Configure the way visitors may log in and limit login attempts.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_login_settings'),
    'access arguments' => array('administer account settings'),
    'file' => 'user.admin.inc',
  );

  // Permissions forms.
  $items['admin/config/people/permissions'] = array(
    'title' => 'Permissions',
    'description' => 'Determine access to features by selecting permissions for roles.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_admin_permissions'),
    'access arguments' => array('administer permissions'),
    'file' => 'user.admin.inc',
  );

  // Role forms.
  $items['admin/config/people/roles'] = array(
    'title' => 'Roles',
    'description' => 'List, edit, or add levels of access, or <em>user roles</em>.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_admin_roles'),
    'access arguments' => array('administer permissions'),
    'file' => 'user.admin.inc',
  );
  $items['admin/config/people/roles/add'] = array(
    'title' => 'Add role',
    'description' => 'Add a new user role.',
    'page arguments' => array('user_admin_role'),
    'access arguments' => array('administer permissions'),
    'type' => MENU_LOCAL_ACTION,
    'file' => 'user.admin.inc',
  );
  $items['admin/config/people/roles/configure/%user_role'] = array(
    'title' => 'Configure role',
    'page arguments' => array('user_admin_role', 5),
    'access arguments' => array('administer permissions'),
  );
  // @deprecated: Remove backwards-compatibility redirect in 2.0.
  $items['admin/config/people/roles/edit/%user_role'] = array(
    'page callback' => 'system_redirect_deprecated_page',
    'page arguments' => array('admin/config/people/roles/configure/%user_role'),
    'access arguments' => array('administer permissions'),
    'type' => MENU_CALLBACK,
  );
  $items['admin/config/people/roles/delete/%user_role'] = array(
    'title' => 'Delete role',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_admin_role_delete_confirm', 5),
    'access callback' => 'user_role_delete_access',
    'access arguments' => array(5),
    'file' => 'user.admin.inc',
  );

  // Emails.
  $items['admin/config/people/emails'] = array(
    'title' => 'Account emails',
    'description' => 'Configure email templates used for account registration and management.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_settings_email'),
    'access arguments' => array('administer account settings'),
    'file' => 'user.admin.inc',
    'weight' => 10,
  );

  $items['user/%user'] = array(
    'title' => 'My account',
    'title callback' => 'user_page_title',
    'title arguments' => array(1),
    'page callback' => 'user_view_page',
    'page arguments' => array(1),
    'access callback' => 'user_view_access',
    'access arguments' => array(1),
    // By assigning a different menu name, this item (and all registered child
    // paths) are no longer considered as children of 'user'. When accessing the
    // user account pages, the preferred menu link that is used to build the
    // active trail (breadcrumb) will be found in this menu (unless there is
    // more specific link), so the link to 'user' will not be in the breadcrumb.
    'menu_name' => 'management',
  );

  $items['user/%user/view'] = array(
    'title' => 'View',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );

  $items['user/%user/cancel'] = array(
    'title' => 'Cancel account',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_cancel_confirm_form', 1),
    'access callback' => 'user_cancel_access',
    'access arguments' => array(1),
    'file' => 'user.pages.inc',
  );

  $items['user/%user/cancel/confirm/%/%'] = array(
    'title' => 'Confirm account cancellation',
    'page callback' => 'user_cancel_confirm',
    'page arguments' => array(1, 4, 5),
    'access callback' => 'user_cancel_access',
    'access arguments' => array(1),
    'file' => 'user.pages.inc',
  );

  $items['user/%user/edit'] = array(
    'title' => 'Edit',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('user_profile_form', 1),
    'access callback' => 'user_edit_access',
    'access arguments' => array(1),
    'type' => MENU_LOCAL_TASK,
    'file' => 'user.pages.inc',
  );
  return $items;
}

/**
 * Implements hook_menu_alter().
 */
function user_menu_alter(&$items) {
  // Add an icon to the Views-provided menu item.
  if (isset($items['admin/people'])) {
    $items['admin/people']['icon'] = 'users-fill';
  }

  if (module_exists('field_ui')) {
    // Provide a parent menu item for managing fields.
    $items['admin/config/people/manage'] = $items['admin/config/people/manage/fields'];
    $items['admin/config/people/manage']['type'] = MENU_NORMAL_ITEM;
    $items['admin/config/people/manage']['weight'] = 1;
    $items['admin/config/people/manage']['description'] = 'Configure fields and display of fields on user accounts.';

    // Set "Manage fields" tab as the default tab.
    $items['admin/config/people/manage/fields']['type'] = MENU_DEFAULT_LOCAL_TASK;
  }
}

/**
 * Implements hook_admin_bar_output_alter().
 */
function user_admin_bar_output_alter(&$content) {
  // Admin menu shows both the parent menu item and its children.
  // Remove the duplicate child element so "Manage fields" doesn't show up
  // twice.
  unset($content['menu']['menu']['admin/config']['admin/config/people']['admin/config/people/manage']['admin/config/people/manage/fields']);
}

/**
 * Implements hook_menu_site_status_alter().
 */
function user_menu_site_status_alter(&$menu_site_status, $path) {
  if ($menu_site_status == MENU_SITE_OFFLINE) {
    // If the site is offline, log out unprivileged users.
    if (user_is_logged_in() && !user_access('access site in maintenance mode')) {
      module_load_include('pages.inc', 'user', 'user');
      user_logout();
    }

    if (user_is_anonymous()) {
      switch ($path) {
        case 'user':
          // Forward anonymous user to login page.
          backdrop_goto('user/login');
        case 'user/login':
        case 'user/password':
          // Disable offline mode.
          $menu_site_status = MENU_SITE_ONLINE;
          break;
        default:
          if (strpos($path, 'user/reset/') === 0) {
            // Disable offline mode.
            $menu_site_status = MENU_SITE_ONLINE;
          }
          break;
      }
    }
  }
  if (user_is_logged_in()) {
    if ($path == 'user/login') {
      // If user is logged in, redirect to 'user' instead of giving 403.
      backdrop_goto('user');
    }
    if ($path == 'user/register') {
      // Authenticated user should be redirected to user edit page.
      backdrop_goto('user/' . $GLOBALS['user']->uid . '/edit');
    }
  }
}

/**
 * Implements hook_menu_link_alter().
 */
function user_menu_link_alter(&$link) {
  // The path 'user' must be accessible for anonymous users, but only visible
  // for authenticated users. Authenticated users should see "My account", but
  // anonymous users should not see it at all. Therefore, invoke
  // user_translated_menu_link_alter() to conditionally hide the link.
  if ($link['link_path'] == 'user' && isset($link['module']) && $link['module'] == 'system') {
    $link['options']['alter'] = TRUE;
  }

  // Force the Logout link to appear on the top-level of 'user-menu' menu by
  // default (i.e., unless it has been customized).
  if ($link['link_path'] == 'user/logout' && isset($link['module']) && $link['module'] == 'system' && empty($link['customized'])) {
    $link['plid'] = 0;
  }
}

/**
 * Implements hook_translated_menu_link_alter().
 */
function user_translated_menu_link_alter(&$link) {
  // Hide the "User account" link for anonymous users.
  if ($link['link_path'] == 'user' && $link['module'] == 'system' && !$GLOBALS['user']->uid) {
    $link['hidden'] = 1;
  }
}

/**
 * Implements hook_admin_paths().
 */
function user_admin_paths() {
  $paths = array(
    'user/*/cancel' => TRUE,
    'user/*/edit' => TRUE,
    'user/*/edit/*' => TRUE,
  );
  return $paths;
}

/**
 * Load either a specified or the current user account.
 *
 * @param $uid
 *   An optional user ID of the user to load. If not provided, the current
 *   user's ID will be used.
 * @return
 *   A fully-loaded $user object upon successful user load, FALSE if user
 *   cannot be loaded.
 *
 * @see user_load()
 * @todo rethink the naming of this.
 */
function user_uid_optional_load($uid = NULL) {
  if (!isset($uid)) {
    $uid = $GLOBALS['user']->uid;
  }
  return user_load($uid);
}

/**
 * Returns $arg or the user ID of the current user if $arg is '%' or empty.
 *
 * @todo rethink the naming of this.
 */
function user_uid_optional_to_arg($arg) {
  // Give back the current user uid when called from eg. tracker, aka.
  // with an empty arg. Also use the current user uid when called from
  // the menu with a % for the current account link.
  return empty($arg) || $arg == '%' ? $GLOBALS['user']->uid : $arg;
}

/**
 * Menu item title callback for the 'user' path.
 *
 * Anonymous users should see "User account", but authenticated users are
 * expected to see "My account".
 */
function user_menu_title() {
  return user_is_logged_in() ? t('My account') : t('User account');
}

/**
 * Menu item title callback - use the user name.
 */
function user_page_title($account) {
  return is_object($account) ? user_format_name($account) : '';
}

/**
 * Form builder; the main user login form.
 *
 * @ingroup forms
 */
function user_login($form, &$form_state) {
  global $user;

  // If we are already logged on, go to the user page instead.
  if ($user->uid) {
    backdrop_goto('user/' . $user->uid);
  }

  backdrop_set_title(t('Log in'));

  // Display login form:
  $credentials = config_get('system.core', 'user_login_method');
  $form['name'] = array('#type' => 'textfield',
    '#title' => $credentials === USER_LOGIN_EMAIL_ONLY ? t('Email address') : ($credentials === USER_LOGIN_USERNAME_OR_EMAIL ? t('Username or email address') : t('Username')),
    '#maxlength' => $credentials === USER_LOGIN_USERNAME_ONLY ? USERNAME_MAX_LENGTH : EMAIL_MAX_LENGTH,
    '#size' => 60,
    '#required' => TRUE,
    '#attributes' => array(
      'autofocus' => 'autofocus',
      // Add attributes to field to prevent spell-jacking and unwanted
      // automatic changes caused by the browser.
      'autocapitalize' => 'none',
      'autocorrect' => 'off',
      'spellcheck' => 'false',
    ),
  );

  $form['pass'] = array(
    '#type' => 'password',
    '#title' => t('Password'),
    '#required' => TRUE,
    '#password_toggle' => TRUE,
  );
  $form['#validate'] = user_login_default_validators();
  $form['actions'] = array('#type' => 'actions');
  $form['actions']['submit'] = array('#type' => 'submit', '#value' => t('Log in'));

  return $form;
}

/**
 * Set up a series for validators which check for blocked users,
 * then authenticate against local database, then return an error if
 * authentication fails. Distributed authentication modules are welcome
 * to use hook_form_alter() to change this series in order to
 * authenticate against their user database instead of the local users
 * table. If a distributed authentication module is successful, it
 * should set $form_state['uid'] to a user ID.
 *
 * We use three validators instead of one since external authentication
 * modules usually only need to alter the second validator.
 *
 * @see user_login_name_validate()
 * @see user_login_authenticate_validate()
 * @see user_login_final_validate()
 * @return array
 *   A simple list of validate functions.
 */
function user_login_default_validators() {
  return array('user_login_name_validate', 'user_login_authenticate_validate', 'user_login_final_validate');
}

/**
 * First phase validation handler for the login form.
 *
 * Check for invalid email addresses and blocked accounts.
 */
function user_login_name_validate($form, &$form_state) {
  // Ensure POST values are strings. Arrays may come from malformed HTML or
  // malicious attacks.
  if (is_array($form_state['values']['name'])) {
    $form_state['values']['name'] = reset($form_state['values']['name']);
  }
  if (is_array($form_state['values']['pass'])) {
    $form_state['values']['pass'] = reset($form_state['values']['pass']);
  }

  $name = trim($form_state['values']['name']);
  if (strlen($name)) {
    $credentials = config_get('system.core', 'user_login_method');
    if ($credentials !== USER_LOGIN_USERNAME_ONLY) {
      if ($account = db_query("SELECT * FROM {users} WHERE mail = :mail", array(':mail' => $name))->fetchObject()) {
        $name = $account->name;
      }
      // If can't find account, check if valid email address.
      elseif ($credentials === USER_LOGIN_EMAIL_ONLY && !valid_email_address($name)) {
        form_set_error('name', t('The email address %email is not valid.', array('%email' => $name)));
      }
    }
    // If can find account, check if user is blocked.
    if ($name && user_is_blocked($name)) {
      form_set_error('name', t('The account for %name has not been activated or is blocked.', array('%name' => $name)));
    }
  }
}

/**
 * Second phase validation handler on the login form.
 *
 * Checks supplied username/password against local users table. If successful,
 * $form_state['uid'] is set to the matching user ID. If an account is found
 * $form_state['account_found'] is set to TRUE, though the password may still
 * fail even if an account is found.
 */
function user_login_authenticate_validate($form, &$form_state) {
  $name = trim($form_state['values']['name']);
  $password = trim($form_state['values']['pass']);
  $flood_config = config('user.flood');
  if (strlen($name) && strlen($password)) {
    // Do not allow any login from the current user's IP if the limit has been
    // reached. Default is 50 failed attempts allowed in one hour. This is
    // independent of the per-user limit to catch attempts from one IP to log
    // in to many different user accounts.  We have a reasonably high limit
    // since there may be only one apparent IP for all users at an institution.
    if (!flood_is_allowed('failed_login_attempt_ip', $flood_config->get('flood_ip_limit'), $flood_config->get('flood_ip_window'))) {
      $form_state['flood_control_triggered'] = 'ip';
      return;
    }
    $account = FALSE;
    $credentials = config_get('system.core', 'user_login_method');
    if (($credentials === USER_LOGIN_USERNAME_OR_EMAIL || $credentials === USER_LOGIN_EMAIL_ONLY) && valid_email_address($name)) {
      $account = db_query("SELECT * FROM {users} WHERE mail = :mail AND status = 1", array(':mail' => $name))->fetchObject();
    }
    if (!$account && $credentials !== USER_LOGIN_EMAIL_ONLY) {
      $account = db_query("SELECT * FROM {users} WHERE name = :name AND status = 1", array(':name' => $name))->fetchObject();
    }

    if ($account) {
      $form_state['account_found'] = TRUE;
      if ($flood_config->get('flood_uid_only')) {
        // Register flood events based on the uid only, so they apply for any
        // IP address. This is the most secure option.
        $identifier = $account->uid;
      }
      else {
        // The default identifier is a combination of uid and IP address. This
        // is less secure but more resistant to denial-of-service attacks that
        // could lock out all users with public user names.
        $identifier = $account->uid . '-' . ip_address();
      }
      $form_state['flood_control_user_identifier'] = $identifier;

      // Don't allow login if the limit for this user has been reached.
      // Default is to allow 5 failed attempts every 6 hours.
      if (!flood_is_allowed('failed_login_attempt_user', $flood_config->get('flood_user_limit'), $flood_config->get('flood_user_window'), $identifier)) {
        $form_state['flood_control_triggered'] = 'user';
        return;
      }
      // We are not limited by flood control, so try to authenticate.
      // Set $form_state['uid'] as a flag for user_login_final_validate().
      $form_state['uid'] = user_authenticate($account->name, $password);
    }
    else {
      $form_state['account_found'] = FALSE;
    }
  }
}

/**
 * The final validation handler on the login form.
 *
 * Sets a form error if user has not been authenticated, or if too many
 * logins have been attempted. This validation function should always
 * be the last one.
 */
function user_login_final_validate($form, &$form_state) {
  $flood_config = config('user.flood');
  if (empty($form_state['uid'])) {
    // Always register an IP-based failed login event.
    flood_register_event('failed_login_attempt_ip', $flood_config->get('flood_ip_window'));
    // Register a per-user failed login event.
    if (isset($form_state['flood_control_user_identifier'])) {
      flood_register_event('failed_login_attempt_user', $flood_config->get('flood_user_window'), $form_state['flood_control_user_identifier']);
    }

    if (isset($form_state['flood_control_triggered'])) {
      if ($form_state['flood_control_triggered'] == 'user') {
        form_set_error('name', format_plural($flood_config->get('flood_user_limit'), 'Sorry, there has been more than one failed login attempt for this account. It is temporarily blocked. Try again later or <a href="@url">request a new password</a>.', 'Sorry, there have been more than @count failed login attempts for this account. It is temporarily blocked. Try again later or <a href="@url">request a new password</a>.', array('@url' => url('user/password'))));
        module_invoke_all('user_flood_control', ip_address(), $form_state['values']['name']);
      }
      else {
        // We did not find a uid, so the limit is IP-based.
        form_set_error('name', t('Sorry, too many failed login attempts from your IP address. This IP address is temporarily blocked. Try again later or <a href="@url">request a new password</a>.', array('@url' => url('user/password'))));
        module_invoke_all('user_flood_control', ip_address());
      }
      // We cannot call backdrop_access_denied() here, as that can result in an
      // infinite loop if the login form is rendered on the 403 page (e.g. in a
      // block). So add the 403 header, and allow form processing to finish.
      backdrop_add_http_header('Status', '403 Forbidden');
    }
    elseif (empty($form_state['account_found'])) {
      $login_method = config_get('system.core', 'user_login_method');
      if ((valid_email_address($form_state['values']['name']) && $login_method === USER_LOGIN_USERNAME_OR_EMAIL) || $login_method === USER_LOGIN_EMAIL_ONLY) {
        form_set_error('name', t('Sorry, no account with that email address found.'));
      }
      else {
        form_set_error('name', t('Sorry, unrecognized username.'));
      }
      watchdog('user', 'The user account or email %name could not be found.', array('%name' => $form_state['values']['name']), WATCHDOG_WARNING);
    }
    else {
      form_set_error('pass', t('Sorry, incorrect password. <a href="@password">Have you forgotten your password?</a>', array('@password' => url('user/password', array('query' => array('name' => $form_state['values']['name']))))));
      watchdog('user', 'Login attempt failed for %user.', array('%user' => $form_state['values']['name']), WATCHDOG_WARNING);
    }
  }
  elseif (isset($form_state['flood_control_user_identifier'])) {
    // Clear past failures for this user so as not to block a user who might
    // log in and out more than once in an hour.
    flood_clear_event('failed_login_attempt_user', $form_state['flood_control_user_identifier']);
  }
}

/**
 * Implements hook_user_flood_control().
 */
function user_user_flood_control($ip, $username = FALSE) {
  if (config_get('user.flood', 'flood_log_failed_attempts')) {
    if (!empty($username)) {
      watchdog('user', 'Flood control blocked login attempt for %user from %ip.', array('%user' => $username, '%ip' => $ip));
    }
    else {
      watchdog('user', 'Flood control blocked login attempt from %ip.', array('%ip' => $ip));
    }
  }
}

/**
 * Try to validate the user's login credentials locally.
 *
 * @param $name
 *   User name to authenticate.
 * @param $password
 *   A plain-text password, such as trimmed text from form values.
 * @return
 *   The user's uid on success, or FALSE on failure to authenticate.
 */
function user_authenticate($name, $password) {
  $uid = FALSE;
  if (!empty($name) && strlen(trim($password)) > 0) {
    $account = user_load_by_name($name);
    if ($account) {
      // Allow alternate password hashing schemes.
      require_once BACKDROP_ROOT . '/' . settings_get('password_inc', 'core/includes/password.inc');
      if (user_check_password($password, $account)) {
        // Successful authentication.
        $uid = $account->uid;

        // Update user to new password scheme if needed.
        if (user_needs_new_hash($account)) {
          $account->pass = $password;
          $account->save();
        }
      }
    }
  }
  return $uid;
}

/**
 * Finalize the login process. Must be called when logging in a user.
 *
 * The function records a watchdog message about the new session, saves the
 * login timestamp, calls hook_user_login(), and generates a new session.
 *
 * @param array $edit
 *   The array of form values submitted by the user.
 *
 * @see hook_user_login()
 */
function user_login_finalize(&$edit = array()) {
  global $user;
  watchdog('user', 'Session opened for %name.', array('%name' => $user->name));
  // Update the user table timestamp noting user has logged in.
  // This is also used to invalidate one-time login links.
  $user->login = REQUEST_TIME;
  db_update('users')
    ->fields(array('login' => $user->login))
    ->condition('uid', $user->uid)
    ->execute();

  // Regenerate the session ID to prevent against session fixation attacks.
  // This is called before hook_user in case one of those functions fails
  // or incorrectly does a redirect which would leave the old session in place.
  backdrop_session_regenerate();

  // If entity caching is enabled, clear the cache entry for the user.
  $entity_info = entity_get_info('user');
  if (isset($entity_info['entity cache']) && $entity_info['entity cache']) {
    cache('entity_user')->delete($user->uid);
  }

  user_module_invoke('login', $edit, $user);
}

/**
 * Submit handler for the login form. Load $user object and perform standard login
 * tasks. The user is then redirected to the My Account page. Setting the
 * destination in the query string overrides the redirect.
 */
function user_login_submit($form, &$form_state) {
  global $user;
  $user = user_load($form_state['uid']);
  $form_state['redirect'] = 'user/' . $user->uid;

  user_login_finalize($form_state);
}

/**
 * Generates a unique URL for a user to login and reset their password.
 *
 * @param object $account
 *   An object containing the user account, which must contain at least the
 *   following properties:
 *   - uid: The user ID number.
 *   - login: The UNIX timestamp of the user's last login.
 *
 * @return
 *   A unique URL that provides a one-time log in for the user, from which
 *   they can change their password.
 */
function user_pass_reset_url($account) {
  $timestamp = REQUEST_TIME;
  return url("user/reset/$account->uid/$timestamp/" . user_pass_rehash($account->pass, $timestamp, $account->login, $account->uid, $account->mail), array('absolute' => TRUE));
}

/**
 * Generates a URL to confirm an account cancellation request.
 *
 * @param object $account
 *   The user account object, which must contain at least the following
 *   properties:
 *   - uid: The user ID number.
 *   - pass: The hashed user password string.
 *   - login: The UNIX timestamp of the user's last login.
 *
 * @return
 *   A unique URL that may be used to confirm the cancellation of the user
 *   account.
 *
 * @see user_mail_tokens()
 * @see user_cancel_confirm()
 */
function user_cancel_url($account) {
  $timestamp = REQUEST_TIME;
  return url("user/$account->uid/cancel/confirm/$timestamp/" . user_pass_rehash($account->pass, $timestamp, $account->login, $account->uid, $account->mail), array('absolute' => TRUE));
}

/**
 * Creates a unique hash value for use in time-dependent per-user URLs.
 *
 * This hash is normally used to build a unique and secure URL that is sent to
 * the user by email for purposes such as resetting the user's password. In
 * order to validate the URL, the same hash can be generated again, from the
 * same information, and compared to the hash value from the URL. The URL
 * normally contains both the time stamp and the numeric user ID. The login
 * timestamp and hashed password are retrieved from the database as necessary.
 * For a usage example, see user_cancel_url() and user_cancel_confirm().
 *
 * @param string $password
 *   The hashed user account password value.
 * @param int $timestamp
 *   A UNIX timestamp, typically REQUEST_TIME.
 * @param int $login
 *   The UNIX timestamp of the user's last login.
 * @param int $uid
 *   The user ID of the user account.
 * @param string $mail
 *   The email address of the user.
 *
 * @return
 *   A string that is safe for use in URLs and SQL statements.
 */
function user_pass_rehash($password, $timestamp, $login, $uid, $mail = '') {
  // Backwards compatibility: Try to determine a $uid if one was not passed.
  // (Since $uid is a required parameter to this function, a PHP warning will
  // be generated if it's not provided, which is an indication that the calling
  // code should be updated. But the code below will try to generate a correct
  // hash in the meantime.)
  if (!isset($uid)) {
    $uids = db_query_range('SELECT uid FROM {users} WHERE pass = :password AND login = :login AND uid > 0', 0, 2, array(':password' => $password, ':login' => $login))->fetchCol();
    // If exactly one user account matches the provided password and login
    // timestamp, proceed with that $uid.
    if (count($uids) == 1) {
      $uid = reset($uids);
    }
    // Otherwise there is no safe hash to return, so return a random string
    // that will never be treated as a valid token.
    else {
      return backdrop_random_key();
    }
  }

  // Backwards compatibility: If the $mail parameter is not provided, load it
  // from the user object.
  if (empty($mail)) {
    $account = user_load($uid);
    $mail = $account->mail;
  }

  return backdrop_hmac_base64($timestamp . ':' . $login . ':' . $uid . ':' . $mail, backdrop_get_hash_salt() . $password);

}

/**
 * Cancel a user account.
 *
 * Since the user cancellation process needs to be run in a batch, either
 * Form API will invoke it, or batch_process() needs to be invoked after calling
 * this function and should define the path to redirect to.
 *
 * @param $edit
 *   An array of submitted form values.
 * @param $uid
 *   The user ID of the user account to cancel.
 * @param $method
 *   The account cancellation method to use.
 *
 * @see _user_cancel()
 */
function user_cancel($edit, $uid, $method) {
  global $user;

  $account = user_load($uid);

  if (!$account) {
    backdrop_set_message(t('The user account %id does not exist.', array('%id' => $uid)), 'error');
    watchdog('user', 'Attempted to cancel non-existing user account: %id.', array('%id' => $uid), WATCHDOG_ERROR);
    return;
  }

  // Initialize batch (to set title).
  $batch = array(
    'title' => t('Cancelling account'),
    'operations' => array(),
  );
  batch_set($batch);

  // When the 'user_cancel_delete' method is used, user_delete() is called,
  // which invokes hook_user_predelete() and hook_user_delete(). Modules
  // should use those hooks to respond to the account deletion.
  if ($method != 'user_cancel_delete') {
    // Allow modules to add further sets to this batch.
    module_invoke_all('user_cancel', $edit, $account, $method);
  }

  // Finish the batch and actually cancel the account.
  $batch = array(
    'title' => t('Cancelling user account'),
    'operations' => array(
      array('_user_cancel', array($edit, $account, $method)),
    ),
  );

  // After cancelling account, ensure that user is logged out.
  if ($account->uid == $user->uid) {
    // Batch API stores data in the session, so use the finished operation to
    // manipulate the current user's session id.
    $batch['finished'] = '_user_cancel_session_regenerate';
  }

  batch_set($batch);

  // Batch processing is either handled via Form API or has to be invoked
  // manually.
}

/**
 * Last batch processing step for cancelling a user account.
 *
 * Since batch and session API require a valid user account, the actual
 * cancellation of a user account needs to happen last.
 *
 * @see user_cancel()
 */
function _user_cancel($edit, $account, $method) {
  global $user;

  switch ($method) {
    case 'user_cancel_block':
    case 'user_cancel_block_unpublish':
    default:
      // Send account blocked notification if option was checked.
      if (!empty($edit['user_cancel_notify'])) {
        _user_mail_notify('status_blocked', $account);
      }
      $account->status = 0;
      $account->save();
      backdrop_set_message(t('%name has been disabled.', array('%name' => $account->name)));
      watchdog('user', 'Blocked user: %name %email.', array('%name' => $account->name, '%email' => '<' . $account->mail . '>'), WATCHDOG_NOTICE);
      break;

    case 'user_cancel_reassign':
    case 'user_cancel_delete':
      // Send account canceled notification if option was checked.
      if (!empty($edit['user_cancel_notify'])) {
        _user_mail_notify('status_canceled', $account);
      }
      user_delete($account->uid);
      backdrop_set_message(t('%name has been deleted.', array('%name' => $account->name)));
      watchdog('user', 'Deleted user: %name %email.', array('%name' => $account->name, '%email' => '<' . $account->mail . '>'), WATCHDOG_NOTICE);
      break;
  }

  // After cancelling account, ensure that user is logged out. We can't destroy
  // their session though, as we might have information in it, and we can't
  // regenerate it because batch API uses the session ID, we will regenerate it
  // in _user_cancel_session_regenerate().
  if ($account->uid == $user->uid) {
    $user = backdrop_anonymous_user();
  }
}

/**
 * Finished batch processing callback for cancelling a user account.
 *
 * @see user_cancel()
 */
function _user_cancel_session_regenerate() {
  // Regenerate the users session instead of calling session_destroy() as we
  // want to preserve any messages that might have been set.
  backdrop_session_regenerate();
}

/**
 * Delete a user.
 *
 * @param $uid
 *   A user ID.
 */
function user_delete($uid) {
  user_delete_multiple(array($uid));
}

/**
 * Delete multiple user accounts.
 *
 * @param $uids
 *   An array of user IDs.
 *
 * @see hook_user_predelete()
 * @see hook_user_delete()
 */
function user_delete_multiple(array $uids) {
  if (!empty($uids)) {
    $accounts = user_load_multiple($uids, array());

    $transaction = db_transaction();
    try {
      foreach ($accounts as $uid => $account) {
        // Allow modules to act prior to user deletion.
        module_invoke_all('user_predelete', $account);
        module_invoke_all('entity_predelete', $account, 'user');

        field_attach_delete('user', $account);
        backdrop_session_destroy_uid($account->uid);
      }

      db_delete('users')
        ->condition('uid', $uids, 'IN')
        ->execute();
      db_delete('users_roles')
        ->condition('uid', $uids, 'IN')
        ->execute();

        // Allow modules to respond to user deletion.
        module_invoke_all('user_delete', $account);
        module_invoke_all('entity_delete', $account, 'user');
    }
    catch (Exception $e) {
      $transaction->rollback();
      watchdog_exception('user', $e);
      throw $e;
    }
    entity_get_controller('user')->resetCache();
  }
}

/**
 * Page callback wrapper for user_view().
 */
function user_view_page($account) {
  // An administrator may try to view a non-existent account,
  // so we give them a 404 (versus a 403 for non-admins).
  return is_object($account) ? user_view($account) : MENU_NOT_FOUND;
}

/**
 * Generate an array for rendering the given user.
 *
 * When viewing a user profile, the $page array contains:
 *
 * - $page['content']['user_picture']:
 *   User's rendered picture.
 * - $page['content']['member_for']:
 *   Contains the default "Member for" profile data for a user.
 * - $page['content']['#account']:
 *   The user account of the profile being viewed.
 *
 * To theme user profiles, copy modules/user/user-profile.tpl.php
 * to your theme directory, and edit it as instructed in that file's comments.
 *
 * @param $account
 *   A user object.
 * @param $view_mode
 *   (optional) Display mode, e.g. 'full' or 'teaser'. Defaults to 'full'.
 * @param $langcode
 *   (optional) A language code to use for rendering. Defaults to the global
 *   content language of the current request.
 *
 * @return
 *   An array as expected by backdrop_render().
 */
function user_view($account, $view_mode = 'full', $langcode = NULL) {
  return $account->view($view_mode, $langcode);
}

/**
 * Builds a structured array representing the profile content.
 *
 * @param $account
 *   A user object.
 * @param $view_mode
 *   (optional) Display mode, e.g. 'full' or 'teaser'. Defaults to 'full'.
 * @param $langcode
 *   (optional) A language code to use for rendering. Defaults to the global
 *   content language of the current request.
 */
function user_build_content($account, $view_mode = 'full', $langcode = NULL) {
  $account->buildContent($view_mode, $langcode);
}

/**
 * Implements hook_mail().
 */
function user_mail($key, &$message, $params) {
  $language = $message['language'];
  $variables = array('user' => $params['account']);
  $message['subject'] .= _user_mail_text($key . '_subject', $language, $variables);
  $message['body'][] = _user_mail_text($key . '_body', $language, $variables);
}

/**
 * Returns a mail string for a variable name.
 *
 * @param string $key
 *   The config key that provides the mail text.
 * @param object $language
 *   A language object.
 * @param array $variables
 *   An array of token keys and values.
 *
 * @return
 *   A string value containing the text for the user.mail config key.
 */
function _user_mail_text($key, $language = NULL, $variables = array()) {
  $langcode = isset($language) ? $language->langcode : NULL;

  // We do not sanitize the token replacement, since the output of this
  // replacement is intended for an email message, not a web browser.
  $text = config('user.mail')->getTranslated($key, array(), array(
    'langcode' => $langcode,
  ));
  $options = array(
    'langcode' => $langcode,
    'callback' => 'user_mail_tokens',
    'sanitize' => FALSE,
    'clear' => TRUE,
  );
  return token_replace($text, $variables, $options);
}

/**
 * Token callback to add unsafe tokens for user mails.
 *
 * This function is used by the token_replace() call at the end of
 * _user_mail_text() to set up some additional tokens that can be
 * used in email messages generated by user_mail().
 *
 * @param $replacements
 *   An associative array variable containing mappings from token names to
 *   values (for use with strtr()).
 * @param $data
 *   An associative array of token replacement values. If the 'user' element
 *   exists, it must contain a user account object with the following
 *   properties:
 *   - login: The UNIX timestamp of the user's last login.
 *   - pass: The hashed account login password.
 * @param $options
 *   Unused parameter required by the token_replace() function.
 */
function user_mail_tokens(&$replacements, $data, $options) {
  if (isset($data['user'])) {
    $replacements['[user:one-time-login-url]'] = user_pass_reset_url($data['user']);
    $replacements['[user:cancel-url]'] = user_cancel_url($data['user']);
  }
}

/*** Administrative features ***********************************************/

/**
 * Retrieve an array of roles matching specified conditions.
 *
 * @param $members_only
 *   Set this to TRUE to exclude the 'anonymous' role.
 * @param $permission
 *   A string containing a permission. If set, only roles containing that
 *   permission are returned.
 * @param $full_objects
 *   TRUE to return complete role objects; FALSE to return role labels.
 *
 * @return array
 *   An associative array of role objects (or role labels, depending on
 *   $full_objects) indexed by role names. Labels and descriptions will already
 *   be translated in the returned values.
 */
function user_roles($members_only = FALSE, $permission = NULL, $full_objects = FALSE) {
  $user_roles = &backdrop_static(__FUNCTION__);

  if (!isset($user_roles)) {
    $user_roles = array();

    // @todo: Consider a cache get here instead of reading from disk.
    $names = config_get_names_with_prefix('user.role.');
    foreach ($names as $config_name) {
      $config = config($config_name);
      $role_name = str_replace('user.role.', '', $config_name);
      $role_data = $config->get();
      $role_data += array(
        'weight' => 0,
        'description' => '',
        'permissions' => array(),
      );
      $user_roles[$role_name] = $role_data;
    }
    backdrop_sort($user_roles, array('weight' => SORT_NUMERIC, 'name' => SORT_STRING));

    // Convert user roles into objects.
    // @todo: Consider using classes and a constructor here.
    foreach ($user_roles as $role_name => $role_data) {
      $user_roles[$role_name] = (object) $user_roles[$role_name];
      $user_roles[$role_name]->label = t($role_data['label']);
      $user_roles[$role_name]->description = t($role_data['description']);
    }
  }

  $return_roles = $user_roles;
  if ($members_only) {
    unset($return_roles['anonymous']);
  }

  if ($permission) {
    foreach ($return_roles as $role_name => $role) {
      if (array_search($permission, $role->permissions) === FALSE) {
        unset($return_roles[$role_name]);
      }
    }
  }

  if (!$full_objects) {
    foreach ($return_roles as $role_name => $role) {
      $return_roles[$role_name] = $role->label;
    }
  }

  return $return_roles;
}

/**
 * Load a user role.
 *
 * @param string $role_name
 *   The role name to be loaded.
 *
 * @return stdClass|FALSE
 *   A fully-loaded role object if a role with the given name exists, or FALSE
 *   otherwise.
 */
function user_role_load($role_name) {
  $roles = user_roles(FALSE, NULL, TRUE);
  return isset($roles[$role_name]) ? $roles[$role_name] : FALSE;
}

/**
 * Legacy wrapper function preserved for backwards-compatibility. This function
 * is no longer used by Backdrop core, since all roles are loaded by name now.
 * See https://docs.backdropcms.org/change-records/converted-user-roles-to-cmi
 *
 * Do not call this function; use user_role_load() instead.
 *
 * @param $role_name
 *   A string representing the role name.
 *
 * @return
 *   A fully-loaded role object if a role with the given name exists, or FALSE
 *   otherwise.
 *
 * @see user_role_load()
 *
 * @deprecated since 1.0.0
 */
function user_role_load_by_name($role_name) {
  watchdog_deprecated_function('user', __FUNCTION__, t('Change record:') . ' ' . l(t('Converted User roles to CMI'), 'https://docs.backdropcms.org/change-records/converted-user-roles-to-cmi', array('attributes' => array('target' => '_blank'))));
  user_role_load($role_name);
}

/**
 * Save a user role to the database.
 *
 * @param stdClass $role
 *   A role object to modify or add.
 * @return int
 *   Status constant indicating if role was created or updated. The constant
 *   SAVED_NEW or SAVED_UPDATED will be returned depending on the operation
 *   performed.
 */
function user_role_save($role) {
  // Trim spaces from names.
  $role->name = trim($role->name);
  $role->label = trim($role->label);
  $role->description = isset($role->description) ? trim($role->description) : '';

  if (!isset($role->weight)) {
    // Set a role weight to make this new role last.
    $weight = 0;
    foreach (user_roles(FALSE, NULL, TRUE) as $existing_role) {
      $weight = max($existing_role->weight, $weight);
    }
    $role->weight = $weight + 1;
  }

  // Let modules modify the user role before it is saved to the database.
  module_invoke_all('user_role_presave', $role);

  $config = config('user.role.' . $role->name);
  $config->set('name', $role->name);
  $config->set('label', $role->label);
  $config->set('description', $role->description);
  $config->set('weight', $role->weight);
  if (isset($role->permissions)) {
    $config->set('permissions', $role->permissions);
  }
  $is_new = $config->isNew();
  $config->save();
  if ($is_new) {
    module_invoke_all('user_role_insert', $role);
    $status = SAVED_NEW;
  }
  else {
    module_invoke_all('user_role_update', $role);
    $status = SAVED_UPDATED;
  }

  // Clear the user access cache.
  backdrop_static_reset('user_roles');
  backdrop_static_reset('user_access');

  return $status;
}

/**
 * Delete a user role from database.
 *
 * @param string $role_name
 *   The name of the role to be deleted.
 */
function user_role_delete($role_name) {
  $role = user_role_load($role_name);

  // If this is the administrator role, explicitly set the "user_admin_role"
  // attribute to "0" (disabled).
  $system_config = config('system.core');
  if ($role_name == $system_config->get('user_admin_role')) {
    $system_config->set('user_admin_role', 0);
    $system_config->save();
  }

  $user_config = config('user.role.' . $role_name);
  $user_config->delete();

  // Update the users who have this role set:
  db_delete('users_roles')
    ->condition('role', $role_name)
    ->execute();

  module_invoke_all('user_role_delete', $role);

  // Clear the user access cache.
  backdrop_static_reset('user_roles');
  backdrop_static_reset('user_access');
}

/**
 * Menu access callback for deleting a user.
 */
function user_role_delete_access($role) {
  // Prevent the system-defined roles from being removed.
  if ($role->name == BACKDROP_ANONYMOUS_ROLE || $role->name == BACKDROP_AUTHENTICATED_ROLE) {
    return FALSE;
  }

  return user_access('administer permissions');
}

/**
 * Determine the modules that permissions belong to.
 *
 * @return
 *   An associative array in the format $permission => $module.
 */
function user_permission_get_modules() {
  $permissions = array();
  foreach (module_implements('permission') as $module) {
    $perms = module_invoke($module, 'permission');
    foreach ($perms as $key => $value) {
      $permissions[$key] = $module;
    }
  }
  return $permissions;
}

/**
 * Change permissions for a user role.
 *
 * This function may be used to grant and revoke multiple permissions at once.
 * For example, when a form exposes checkboxes to configure permissions for a
 * role, the form submit handler may directly pass the submitted values for the
 * checkboxes form element to this function.
 *
 * @param string $role_name
 *   The name of a user role to alter.
 * @param array $permissions
 *   An associative array, where the key holds the permission name and the value
 *   determines whether to grant or revoke that permission. Any value that
 *   evaluates to TRUE will cause the permission to be granted. Any value that
 *   evaluates to FALSE will cause the permission to be revoked.
 *   @code
 *     array(
 *       'administer nodes' => 0,                // Revoke 'administer nodes'
 *       'administer blocks' => FALSE,           // Revoke 'administer blocks'
 *       'access user profiles' => 1,            // Grant 'access user profiles'
 *       'access content' => TRUE,               // Grant 'access content'
 *       'access comments' => 'access comments', // Grant 'access comments'
 *     )
 *   @endcode
 *   Existing permissions are not changed, unless specified in $permissions.
 *
 * @see user_role_grant_permissions()
 * @see user_role_revoke_permissions()
 */
function user_role_change_permissions($role_name, array $permissions = array()) {
  // Grant new permissions for the role.
  $grant = array_filter($permissions);
  if (!empty($grant)) {
    user_role_grant_permissions($role_name, array_keys($grant));
  }
  // Revoke permissions for the role.
  $revoke = array_diff_assoc($permissions, $grant);
  if (!empty($revoke)) {
    user_role_revoke_permissions($role_name, array_keys($revoke));
  }
}

/**
 * Grant permissions to a user role.
 *
 * @param string $role_name
 *   The name of a user role to alter.
 * @param array $permissions
 *   A list of permission names to grant.
 *
 * @see user_role_change_permissions()
 * @see user_role_revoke_permissions()
 */
function user_role_grant_permissions($role_name, array $permissions = array()) {
  $user_role = user_role_load($role_name);
  $user_role->permissions = array_values(array_unique(array_merge($user_role->permissions, $permissions)));
  user_role_save($user_role);
}

/**
 * Revoke permissions from a user role.
 *
 * @param string $role_name
 *   The name of a user role to alter.
 * @param array $permissions
 *   A list of permission names to revoke.
 *
 * @see user_role_change_permissions()
 * @see user_role_grant_permissions()
 */
function user_role_revoke_permissions($role_name, array $permissions = array()) {
  // Revoke permissions for the role.
  $user_role = user_role_load($role_name);
  $user_role->permissions = array_values(array_diff($user_role->permissions, $permissions));
  user_role_save($user_role);
}

/**
 * List user administration filters that can be applied.
 */
function user_filters() {
  $filters = array();
  $roles = user_roles(TRUE);
  // Don't list the authenticated user role.
  unset($roles[BACKDROP_AUTHENTICATED_ROLE]);
  if (count($roles)) {
    $filters['role'] = array(
      'title' => t('role'),
      'field' => 'ur.role',
      'options' => array(
        '[any]' => t('any'),
      ) + $roles,
    );
  }

  $options = array();
  $module_info = system_get_info('module');
  foreach (module_implements('permission') as $module) {
    $function = $module . '_permission';
    $module_group = t('@module module', array('@module' => $module_info[$module]['name']));
    if ($permissions = $function()) {
      asort($permissions);
      foreach ($permissions as $permission => $permission_info) {
        $options[$module_group][$permission] = $permission_info['title'];
      }
    }
  }
  ksort($options);
  $filters['permission'] = array(
    'title' => t('permission'),
    'options' => array(
      '[any]' => t('any'),
    ) + $options,
  );

  $filters['status'] = array(
    'title' => t('status'),
    'field' => 'u.status',
    'options' => array(
      '[any]' => t('any'),
      1 => t('active'),
      0 => t('blocked'),
    ),
  );
  return $filters;
}

/**
 * Extends a query object for user administration filters based on session.
 *
 * @param $query
 *   Query object that should be filtered.
 */
function user_build_filter_query(SelectQuery $query) {
  $filters = user_filters();
  // Extend Query with filter conditions.
  foreach (isset($_SESSION['user_overview_filter']) ? $_SESSION['user_overview_filter'] : array() as $filter) {
    list($key, $value) = $filter;
    // This checks to see if this permission filter is an enabled permission for
    // the authenticated role. If so, then all users would be listed, and we can
    // skip adding it to the filter query.
    if ($key == 'permission') {
      $account = entity_create('user', array());
      $account->uid = 'user_filter';
      $account->roles = array(BACKDROP_AUTHENTICATED_ROLE);
      if (user_access($value, $account)) {
        continue;
      }
      $role_list = array();
      $user_roles = user_roles(FALSE, NULL, TRUE);
      foreach ($user_roles as $user_role) {
        if (in_array($value, $user_role->permissions)) {
          $role_list[] = $user_role->name;
        }
      }
      $users_roles_alias = $query->join('users_roles', 'ur', '%alias.uid = u.uid');
      $query->condition($users_roles_alias . '.role', $role_list);
    }
    elseif ($key == 'role') {
      $users_roles_alias = $query->join('users_roles', 'ur', '%alias.uid = u.uid');
      $query->condition($users_roles_alias . '.role' , $value);
    }
    else {
      $query->condition($filters[$key]['field'], $value);
    }
  }
}

/**
 * Implements hook_comment_view().
 */
function user_comment_view($comment) {
  if (config_get('system.core', 'user_signatures') && !empty($comment->signature)) {
    // @todo This alters and replaces the original object value, so a
    //   hypothetical process of loading, viewing, and saving will hijack the
    //   stored data. Consider renaming to $comment->signature_safe or similar
    //   here and elsewhere in Backdrop.
    $comment->signature = check_markup($comment->signature, $comment->signature_format, '', TRUE);
  }
  else {
    $comment->signature = '';
  }
}

/**
 * Get the language object preferred by the user. This user preference can
 * be set on the user account editing page, and is only available if there
 * are more than one languages enabled on the site. If the user did not
 * choose a preferred language, or is the anonymous user, the $default
 * value, or if it is not set, the site default language will be returned.
 *
 * @param $account
 *   User account to look up language for.
 * @param $default
 *   Optional default language object to return if the account
 *   has no valid language.
 */
function user_preferred_language($account, $default = NULL) {
  $language_list = language_list();
  if (!empty($account->language) && isset($language_list[$account->language])) {
    return $language_list[$account->language];
  }
  else {
    return $default ? $default : language_default();
  }
}

/**
 * Conditionally create and send a notification email when a certain
 * operation happens on the given user account.
 *
 * @see user_mail_tokens()
 * @see backdrop_mail()
 *
 * @param $op
 *   The operation being performed on the account. Possible values:
 *   - 'register_admin_created': Welcome message for user created by the admin.
 *   - 'register_no_approval_required': Welcome message when user
 *     self-registers.
 *   - 'register_pending_approval': Welcome message, user pending admin
 *     approval.
 *   - 'password_reset': Password recovery request.
 *   - 'status_activated': Account activated.
 *   - 'status_blocked': Account blocked.
 *   - 'cancel_confirm': Account cancellation request.
 *   - 'status_canceled': Account canceled.
 *
 * @param $account
 *   The user object of the account being notified. Must contain at
 *   least the fields 'uid', 'name', and 'mail'.
 * @param $language
 *   Optional language to use for the notification, overriding account language.
 *
 * @return
 *   The return value from backdrop_mail_system()->mail(), if ends up being
 *   called.
 */
function _user_mail_notify($op, $account, $language = NULL) {
  // We always notify unless specifically set otherwise. Canceled and blocked
  // are disabled by default, but everything else will notify. Not all options
  // have a checkbox in the UI.
  $default_notify = ($op != 'status_canceled' && $op != 'status_blocked');
  $config = config('system.core');
  $notify = $config->get('user_mail_' . $op . '_notify');
  $notify = isset($notify) ? $notify :  $default_notify;
  if ($notify) {
    $params['account'] = $account;
    $language = $language ? $language : user_preferred_language($account);
    $mail = backdrop_mail('user', $op, $account->mail, $language, $params);
    if ($op == 'register_pending_approval') {
      // If a user registered requiring admin approval, notify the admin, too.
      // We use the site default language for this.
      $site_mail = $config->get('site_mail');
      if (empty($site_mail)) {
        $site_mail = ini_get('sendmail_from');
      }
      backdrop_mail('user', 'register_pending_approval_admin', $site_mail, language_default(), $params);

    }
  }
  return empty($mail) ? NULL : $mail['result'];
}

/**
 * Form element process handler for client-side password hide/show and strength.
 *
 * @param array $element
 *   The form element to process.
 * @param array $form_state
 *   The $form_state array of the form this element belongs to.
 */
function user_form_process_password($element, $form_state = array()) {
  global $user;
  $config = config('system.core');

  if ($element['#password_strength']) {
    if (isset($form_state['user']) && is_a($form_state['user'], 'User')) {
      // Existing account, not the current user if an admin edits an account.
      $username = $form_state['user']->name;
      $email = $form_state['user']->mail;
    }
    else {
      // The AnonymousUser object has no mail property, and name is NULL.
      // The User object has both mail and name set.
      $username = (isset($user->name) ? $user->name : '');
      $email = (isset($user->mail) ? $user->mail : '');
    }
    $strength_settings = array(
      'scores' => array(
        'weak' => USER_PASSWORD_STRENGTH_WEAK,
        'fair' => USER_PASSWORD_STRENGTH_FAIR,
        'good' => USER_PASSWORD_STRENGTH_GOOD,
        'strong' => USER_PASSWORD_STRENGTH_STRONG,
      ),
      'labels' => array(
        'strengthTitle' => t('Password strength: '),
        'weak' => t('weak'),
        'fair' => t('fair'),
        'good' => t('good'),
        'strong' => t('excellent'),
      ),
      'data' => array(
        'username' => $username,
        'email' => $email,
      ),
      'config' => array(
        'strengthModifier' => USER_PASSWORD_STRENGTH_MODIFIER,
      ),
    );

    $element['#attributes']['data-password-strength'] = backdrop_json_encode($strength_settings, FALSE);
  }

  if ($element['#password_toggle']) {
    $toggle_settings = array(
      'toggleShowTitle' => t('Show password'),
      'toggleHideTitle' => t('Hide password'),
      'toggleDefault' => $element['#password_shown'] ? 'show' : 'hide',
    );

    $element['#attributes']['data-password-toggle'] = backdrop_json_encode($toggle_settings, FALSE);
  }

  if ($element['#password_strength'] || $element['#password_toggle']) {
    $element['#attached']['js'][] = backdrop_get_path('module', 'user') . '/js/user.js';
  }
  return $element;
}

/**
 * Form element process handler for client-side password validation.
 *
 * This #process handler is automatically invoked for 'password_confirm' form
 * elements to add the JavaScript and string translations for dynamic password
 * validation.
 *
 * @see system_element_info()
 */
function user_form_process_password_confirm($element) {
  $confirm_settings = array(
    'confirmTitle' => t('Passwords match: '),
    'confirmSuccess' => t('yes'),
    'confirmFailure' => t('no'),
  );

  $element['#attached']['js'][] = backdrop_get_path('module', 'user') . '/js/user.js';
  $element['pass2']['#attributes']['data-password-confirm'] = backdrop_json_encode($confirm_settings, FALSE);

  return $element;
}

/**
 * Implements hook_node_load().
 */
function user_node_load($nodes, $types) {
  // Build an array of all uids for node authors, keyed by nid.
  $uids = array();
  foreach ($nodes as $nid => $node) {
    $uids[$nid] = $node->uid;
  }

  // Fetch name, picture, and data for these users.
  $user_fields = db_query("SELECT uid, name, picture, data FROM {users} WHERE uid IN (:uids)", array(':uids' => $uids))->fetchAllAssoc('uid');

  // Add these values back into the node objects.
  foreach ($uids as $nid => $uid) {
    $nodes[$nid]->name = $user_fields[$uid]->name;
    $nodes[$nid]->picture = $user_fields[$uid]->picture;
    $nodes[$nid]->data = $user_fields[$uid]->data;
  }
}

/**
 * Implements hook_image_style_delete().
 */
function user_image_style_delete($style) {
  // If a style is deleted, update the variables.
  // Administrators choose a replacement style when deleting.
  user_image_style_save($style);
}

/**
 * Implements hook_image_style_save().
 */
function user_image_style_save($style) {
  // If a style is renamed, update the variables that use it.
  if (isset($style['old_name']) && $style['old_name'] == config_get('system.core', 'user_picture_style')) {
    config_set('system.core', 'user_picture_style', $style['name']);
  }
}

/**
 * Implements hook_action_info().
 */
function user_action_info() {
  $actions['user_block_user_action'] = array(
    'label' => t('Block user(s)'),
    'type' => 'user',
    'callback' => 'user_block_user_action',
    'file' => 'user.actions.inc',
    'weight' => -2,
  );
  $actions['user_unblock_user_action'] = array(
    'label' => t('Unblock user(s)'),
    'type' => 'user',
    'callback' => 'user_unblock_user_action',
    'file' => 'user.actions.inc',
    'weight' => -1,
  );
  $actions['user_cancel_user_action'] = array(
    'label' => t('Cancel user account(s)'),
    'type' => 'user',
    'callback' => 'user_cancel_user_action',
    'file' => 'user.actions.inc',
    'weight' => 10,
  );

  $roles = user_roles(TRUE, NULL, TRUE);
  $index = 0;
  foreach ($roles as $role_name => $role) {
    if ($role_name === BACKDROP_AUTHENTICATED_ROLE) {
      continue;
    }
    if (!user_access('assign roles') && !user_access('administer permissions')) {
      continue;
    }
    $index++;

    $actions['user_add_role_' . $role_name] = array(
      'label' => t('Add role "@label"', array('@label' => $role->label)),
      'type' => 'user',
      'callback' => 'user_add_role_action',
      'file' => 'user.actions.inc',
      'weight' => 120 + $index,
      'role_name' => $role_name,
    );
    $actions['user_remove_role_' . $role_name] = array(
      'label' => t('Remove role "@label"', array('@label' => $role->label)),
      'type' => 'user',
      'callback' => 'user_remove_role_action',
      'file' => 'user.actions.inc',
      'weight' => 150 + $index,
      'role_name' => $role_name,
    );
  }

  return $actions;
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Add a checkbox for the 'user_register_form' instance settings on the 'Edit
 * field instance' form.
 */
function user_form_field_ui_field_edit_form_alter(&$form, &$form_state, $form_id) {
  $instance = $form['#instance'];

  if ($instance['entity_type'] == 'user' && !$form['#field']['locked']) {
    $form['instance']['settings']['user_register_form'] = array(
      '#type' => 'checkbox',
      '#title' => t('Display on user registration form.'),
      '#description' => t("This is compulsory for 'required' fields."),
      // Field instances created in D7 beta releases before the setting was
      // introduced might be set as 'required' and 'not shown on user_register
      // form'. We make sure the checkbox comes as 'checked' for those.
      '#default_value' => $instance['settings']['user_register_form'] || $instance['required'],
      // Display just below the 'required' checkbox.
      '#weight' => $form['instance']['required']['#weight'] + .1,
      // Disabled when the 'required' checkbox is checked.
      '#states' => array(
        'enabled' => array('input[name="instance[required]"]' => array('checked' => FALSE)),
      ),
      // Checked when the 'required' checkbox is checked. This is done through
      // a custom behavior, since the #states system would also synchronize on
      // uncheck.
      '#attached' => array(
        'js' => array(backdrop_get_path('module', 'user') . '/js/user.js'),
      ),
    );

    array_unshift($form['#submit'], 'user_form_field_ui_field_edit_form_submit');
  }
}

/**
 * Additional submit handler for the 'Edit field instance' form.
 *
 * Make sure the 'user_register_form' setting is set for required fields.
 */
function user_form_field_ui_field_edit_form_submit($form, &$form_state) {
  $instance = $form_state['values']['instance'];

  if (!empty($instance['required'])) {
    form_set_value($form['instance']['settings']['user_register_form'], 1, $form_state);
  }
}

/**
 * Menu callback to create a new account.
 *
 * @since 1.23.1 Replaces user_register_form() as menu callback.
 *
 * @see user_register_form()
 */
function user_register_page() {
  // We need to set the page title because this menu entry is a local task.
  backdrop_set_title(t('Create new account'));
  return backdrop_get_form('user_register_form');
}

/**
 * Form builder; the user registration form.
 *
 * @ingroup forms
 * @see user_account_form()
 * @see user_account_form_validate()
 * @see user_register_submit()
 */
function user_register_form($form, &$form_state) {
  global $user;
  $admin = user_access('administer users');

  // Pass access information to the submit handler. Running an access check
  // inside the submit function interferes with form processing and breaks
  // hook_form_alter().
  $form['administer_users'] = array(
    '#type' => 'value',
    '#value' => $admin,
  );

  // If we aren't admin but already logged on, go to the user page instead.
  if (!$admin && $user->uid) {
    backdrop_goto('user/' . $user->uid);
  }

  $form['#user'] = entity_create('user', array());

  $form['#attached']['library'][] = array('system', 'jquery.cookie');
  $form['#attributes']['class'][] = 'user-info-from-cookie';

  // Start with the default user account fields.
  user_account_form($form, $form_state);

  // Attach field widgets, and hide the ones where the 'user_register_form'
  // setting is not on.
  field_attach_form('user', $form['#user'], $form, $form_state);
  foreach (field_info_instances('user', 'user') as $field_name => $instance) {
    if (empty($instance['settings']['user_register_form'])) {
      $form[$field_name]['#access'] = FALSE;
    }
  }

  if ($admin) {
    // Redirect back to page which initiated the create request;
    // usually admin/people/create.
    $form_state['redirect'] = $_GET['q'];
  }

  // Prepare cancel link.
  if (isset($_GET['destination'])) {
    $path = $_GET['destination'];
  }
  elseif (isset($_SERVER['HTTP_REFERER'])) {
    $path = $_SERVER['HTTP_REFERER'];
  }
  elseif ($admin) {
    $path = 'admin/people';
  }
  else {
    $path = '<front>';
  }
  $options = backdrop_parse_url($path);
  $options['attributes']['class'][] = 'form-cancel';

  $form['actions'] = array('#type' => 'actions');
  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Create new account'),
  );
  $form['actions']['cancel'] = array(
    '#type' => 'link',
    '#title' => t('Cancel'),
    '#href' => $options['path'],
    '#options' => $options,
    '#weight' => 1,
  );

  $form['#validate'][] = 'user_register_validate';
  // Add the final user registration form submit handler.
  $form['#submit'][] = 'user_register_submit';

  return $form;
}

/**
 * Validation function for the user registration form.
 */
function user_register_validate($form, &$form_state) {
  entity_form_field_validate('user', $form, $form_state);
}

/**
 * Submit handler for the user registration form.
 *
 * This function is shared by the installation form and the normal registration form,
 * which is why it can't be in the user.pages.inc file.
 *
 * @see user_register_form()
 */
function user_register_submit($form, &$form_state) {
  $user_email_verification = config_get('system.core', 'user_email_verification');
  $admin = $form_state['values']['administer_users'];

  if (!$user_email_verification || $admin) {
    $pass = $form_state['values']['pass'];
  }
  else {
    $pass = user_password();
  }
  $notify = !empty($form_state['values']['notify']);

  // Remove unneeded values.
  form_state_values_clean($form_state);

  // Convert checkbox values to an unindexed list.
  if (isset($form_state['values']['roles'])) {
    $form_state['values']['roles'] = array_keys(array_filter($form_state['values']['roles']));
  }

  $form_state['values']['pass'] = $pass;
  $form_state['values']['init'] = $form_state['values']['mail'];

  $account = $form['#user'];

  entity_form_submit_build_entity('user', $account, $form, $form_state);
  $status = $account->save();

  // Terminate if an error occurred while saving the account.
  if ($status != SAVED_NEW) {
    backdrop_set_message(t("Error saving user account."), 'error');
    $form_state['redirect'] = '';
    return;
  }
  $form_state['user'] = $account;
  $form_state['values']['uid'] = $account->uid;

  watchdog('user', 'New user: %name (%email).', array('%name' => $form_state['values']['name'], '%email' => $form_state['values']['mail']), WATCHDOG_NOTICE, l(t('edit'), 'user/' . $account->uid . '/edit'));

  // Add plain text password into user account to generate mail tokens.
  $account->password = $pass;

  // New administrative account without notification.
  $uri = $account->uri();
  if ($admin && !$notify) {
    backdrop_set_message(t('Created a new user account for <a href="@url">%name</a>. No email has been sent.', array('@url' => url($uri['path'], $uri['options']), '%name' => $account->name)));
  }
  // No email verification required; log in user immediately.
  elseif (!$admin && !$user_email_verification && $account->status) {
    _user_mail_notify('register_no_approval_required', $account);
    $form_state['uid'] = $account->uid;
    user_login_submit(array(), $form_state);
    backdrop_set_message(t('Registration successful. You are now logged in.'));
    $form_state['redirect'] = '';
  }
  // No administrator approval required.
  elseif ($account->status || $notify) {
    $op = $notify ? 'register_admin_created' : 'register_no_approval_required';
    _user_mail_notify($op, $account);
    if ($notify) {
      backdrop_set_message(t('A welcome message with further instructions has been emailed to the new user <a href="@url">%name</a>.', array('@url' => url($uri['path'], $uri['options']), '%name' => $account->name)));
    }
    else {
      backdrop_set_message(t('A welcome message with further instructions has been sent to your email address.'));
      $form_state['redirect'] = '';
    }
  }
  // Administrator approval required.
  else {
    _user_mail_notify('register_pending_approval', $account);
    backdrop_set_message(t('Thank you for applying for an account. Your account is currently pending approval by the site administrator.<br />In the meantime, a welcome message with further instructions has been sent to your email address.'));
    $form_state['redirect'] = '';
  }
}

/**
 * Implements hook_modules_installed().
 */
function user_modules_installed($modules) {
  // Assign all available permissions to the administrator role.
  $role_name = config_get('system.core', 'user_admin_role');
  $role = user_role_load($role_name);
  if ($role) {
    $permissions = array();
    foreach ($modules as $module) {
      if ($module_permissions = module_invoke($module, 'permission')) {
        $permissions = array_merge($permissions, array_keys($module_permissions));
      }
    }
    if (!empty($permissions)) {
      user_role_grant_permissions($role_name, $permissions);
    }
  }
}

/**
 * Implements hook_modules_uninstalled().
 */
function user_modules_uninstalled($modules) {
  // Remove permissions provided by a module upon uninstall.
  $removed_permissions = array();
  foreach ($modules as $module_name) {
    if ($module_permissions = module_invoke($module_name, 'permission')) {
      $removed_permissions = array_merge($removed_permissions, array_keys($module_permissions));
    }
  }

  $roles = user_roles();
  foreach ($roles as $role_name => $role_label) {
    user_role_revoke_permissions($role_name, $removed_permissions);
  }
}

/**
 * Helper function to rewrite the destination to avoid redirecting to login page after login.
 *
 * Third-party authentication modules may use this function to determine the
 * proper destination after a user has been properly logged in.
 */
function user_login_destination() {
  global $user;
  $destination = backdrop_get_destination();
  if ($destination['destination'] == 'user/login') {
    $destination['destination'] = 'user/' . $user->uid;
  }
  return $destination;
}

/**
 * Saves visitor information as a cookie so it can be reused.
 *
 * @param $values
 *   An array of key/value pairs to be saved into a cookie.
 */
function user_cookie_save(array $values) {
  foreach ($values as $field => $value) {
    // Set cookie for 365 days.
    setrawcookie('Backdrop.visitor.' . $field, rawurlencode($value), REQUEST_TIME + 31536000, '/');
  }
}

/**
 * Delete a visitor information cookie.
 *
 * @param $cookie_name
 *   A cookie name such as 'homepage'.
 */
function user_cookie_delete($cookie_name) {
  setrawcookie('Backdrop.visitor.' . $cookie_name, '', REQUEST_TIME - 3600, '/');
}

/**
 * Implements hook_autoload_info().
 */
function user_autoload_info() {
  return array(
    'User' => 'user.entity.inc',
    'UserStorageController' => 'user.entity.inc',

    // Views handlers.
    'views_handler_argument_user_uid' => 'views/views_handler_argument_user_uid.inc',
    'views_handler_argument_users_roles' => 'views/views_handler_argument_users_roles.inc',
    'views_handler_field_user' => 'views/views_handler_field_user.inc',
    'views_handler_field_user_language' => 'views/views_handler_field_user_language.inc',
    'views_handler_field_user_link' => 'views/views_handler_field_user_link.inc',
    'views_handler_field_user_link_cancel' => 'views/views_handler_field_user_link_cancel.inc',
    'views_handler_field_user_link_edit' => 'views/views_handler_field_user_link_edit.inc',
    'views_handler_field_user_mail' => 'views/views_handler_field_user_mail.inc',
    'views_handler_field_user_name' => 'views/views_handler_field_user_name.inc',
    'views_handler_field_user_permissions' => 'views/views_handler_field_user_permissions.inc',
    'views_handler_field_user_picture' => 'views/views_handler_field_user_picture.inc',
    'views_handler_field_user_roles' => 'views/views_handler_field_user_roles.inc',
    'views_handler_filter_user_current' => 'views/views_handler_filter_user_current.inc',
    'views_handler_filter_user_name' => 'views/views_handler_filter_user_name.inc',
    'views_handler_filter_user_permissions' => 'views/views_handler_filter_user_permissions.inc',
    'views_handler_filter_user_roles' => 'views/views_handler_filter_user_roles.inc',
    'views_plugin_argument_default_current_user' => 'views/views_plugin_argument_default_current_user.inc',
    'views_plugin_argument_default_user' => 'views/views_plugin_argument_default_user.inc',
    'views_plugin_argument_validate_user' => 'views/views_plugin_argument_validate_user.inc',
    'views_plugin_row_user_view' => 'views/views_plugin_row_user_view.inc',
  );
}

/**
 * Implements hook_file_download_access().
 */
function user_file_download_access($field, $entity_type, $entity) {
  if ($entity_type == 'user') {
    return user_view_access($entity);
  }
}