<?php

namespace Drupal\Core\Session;

/**
 * Defines an account interface which represents the current user.
 *
 * Defines an object that has a user id, roles and can have session data. The
 * interface is implemented both by the global session and the user entity.
 *
 * @ingroup user_api
 */
interface AccountInterface {

  /**
   * Role ID for anonymous users.
   */
  const ANONYMOUS_ROLE = 'anonymous';

  /**
   * Role ID for authenticated users.
   */
  const AUTHENTICATED_ROLE = 'authenticated';

  /**
   * Returns the user ID or 0 for anonymous.
   *
   * @return int
   *   The user ID.
   */
  public function id();

  /**
   * Returns a list of roles.
   *
   * @param bool $exclude_locked_roles
   *   (optional) If TRUE, locked roles (anonymous/authenticated) are not returned.
   *
   * @return array
   *   List of role IDs.
   */
  public function getRoles($exclude_locked_roles = FALSE);

  /**
   * Checks whether a user has a certain permission.
   *
   * @param string $permission
   *   The permission string to check.
   *
   * @return bool
   *   TRUE if the user has the permission, FALSE otherwise.
   */
  public function hasPermission($permission);

  /**
   * Returns TRUE if the account is authenticated.
   *
   * @return bool
   *   TRUE if the account is authenticated.
   */
  public function isAuthenticated();

  /**
   * Returns TRUE if the account is anonymous.
   *
   * @return bool
   *   TRUE if the account is anonymous.
   */
  public function isAnonymous();

  /**
   * Returns the preferred language code of the account.
   *
   * @param bool $fallback_to_default
   *   (optional) Whether the return value will fall back to the site default
   *   language if the user has no language preference.
   *
   * @return string
   *   Returned language code depends upon following:
   *   - The user preferred language code is returned if set in the account.
   *   - If the user has no preferred language and $fallback_to_default is TRUE
   *     then the site default language code is returned.
   *   - If the user has no preferred language and $fallback_to_default is FALSE
   *     then empty string is returned.
   */
  public function getPreferredLangcode($fallback_to_default = TRUE);

  /**
   * Returns the preferred administrative language code of the account.
   *
   * Defines which language is used on administrative pages.
   *
   * @param bool $fallback_to_default
   *   (optional) Whether the return value will fall back to the site default
   *   language if the user has no administration language preference.
   *
   * @return string
   *   The language code that is preferred by the account for administration
   *   pages. If the preferred language is not set or is a language not
   *   configured anymore on the site, the site default is returned or an empty
   *   string is returned (if $fallback_to_default is FALSE).
   */
  public function getPreferredAdminLangcode($fallback_to_default = TRUE);

  /**
   * Returns the unaltered login name of this account.
   *
   * @return string
   *   An unsanitized plain-text string with the name of this account that is
   *   used to log in. Only display this name to admins and to the user who owns
   *   this account, and only in the context of the name used to login. For
   *   any other display purposes, use
   *   \Drupal\Core\Session\AccountInterface::getDisplayName() instead.
   */
  public function getAccountName();

  /**
   * Returns the display name of this account.
   *
   * 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()
   *
   * @return string|\Drupal\Component\Render\MarkupInterface
   *   Either a string that will be auto-escaped on output or a
   *   MarkupInterface object that is already HTML escaped. Either is safe
   *   to be printed within HTML fragments.
   */
  public function getDisplayName();

  /**
   * Returns the email address of this account.
   *
   * @return string|null
   *   The email address, or NULL if the account is anonymous or the user does
   *   not have an email address.
   */
  public function getEmail();

  /**
   * Returns the timezone of this account.
   *
   * @return string
   *   Name of the timezone.
   */
  public function getTimeZone();

  /**
   * The timestamp when the account last accessed the site.
   *
   * A value of 0 means the user has never accessed the site.
   *
   * @return int
   *   Timestamp of the last access.
   */
  public function getLastAccessedTime();

}
