<?php
  
  /**
   * Implement this interface to create your own principal backends.
   *
   * Creating backends for principals is entirely optional. You can also
   * implement Sabre_DAVACL_IPrincipal directly. This interface is used solely by
   * Sabre_DAVACL_AbstractPrincipalCollection.
   *
   * @package Sabre
   * @subpackage DAVACL
   * @copyright Copyright (C) 2007-2013 Rooftop Solutions. All rights reserved.
   * @author Evert Pot (http://www.rooftopsolutions.nl/)
   * @license http://code.google.com/p/sabredav/wiki/License Modified BSD License
   */
  interface Sabre_DAVACL_IPrincipalBackend {
  
      /**
       * Returns a list of principals based on a prefix.
       *
       * This prefix will often contain something like 'principals'. You are only
       * expected to return principals that are in this base path.
       *
       * You are expected to return at least a 'uri' for every user, you can
       * return any additional properties if you wish so. Common properties are:
       *   {DAV:}displayname
       *   {http://sabredav.org/ns}email-address - This is a custom SabreDAV
       *     field that's actually injected in a number of other properties. If
       *     you have an email address, use this property.
       *
       * @param string $prefixPath
       * @return array
       */
      function getPrincipalsByPrefix($prefixPath);
  
      /**
       * Returns a specific principal, specified by it's path.
       * The returned structure should be the exact same as from
       * getPrincipalsByPrefix.
       *
       * @param string $path
       * @return array
       */
      function getPrincipalByPath($path);
  
      /**
       * Updates one ore more webdav properties on a principal.
       *
       * The list of mutations is supplied as an array. Each key in the array is
       * a propertyname, such as {DAV:}displayname.
       *
       * Each value is the actual value to be updated. If a value is null, it
       * must be deleted.
       *
       * This method should be atomic. It must either completely succeed, or
       * completely fail. Success and failure can simply be returned as 'true' or
       * 'false'.
       *
       * It is also possible to return detailed failure information. In that case
       * an array such as this should be returned:
       *
       * array(
       *   200 => array(
       *      '{DAV:}prop1' => null,
       *   ),
       *   201 => array(
       *      '{DAV:}prop2' => null,
       *   ),
       *   403 => array(
       *      '{DAV:}prop3' => null,
       *   ),
       *   424 => array(
       *      '{DAV:}prop4' => null,
       *   ),
       * );
       *
       * In this previous example prop1 was successfully updated or deleted, and
       * prop2 was succesfully created.
       *
       * prop3 failed to update due to '403 Forbidden' and because of this prop4
       * also could not be updated with '424 Failed dependency'.
       *
       * This last example was actually incorrect. While 200 and 201 could appear
       * in 1 response, if there's any error (403) the other properties should
       * always fail with 423 (failed dependency).
       *
       * But anyway, if you don't want to scratch your head over this, just
       * return true or false.
       *
       * @param string $path
       * @param array $mutations
       * @return array|bool
       */
      function updatePrincipal($path, $mutations);
  
      /**
       * This method is used to search for principals matching a set of
       * properties.
       *
       * This search is specifically used by RFC3744's principal-property-search
       * REPORT. You should at least allow searching on
       * http://sabredav.org/ns}email-address.
       *
       * The actual search should be a unicode-non-case-sensitive search. The
       * keys in searchProperties are the WebDAV property names, while the values
       * are the property values to search on.
       *
       * If multiple properties are being searched on, the search should be
       * AND'ed.
       *
       * This method should simply return an array with full principal uri's.
       *
       * If somebody attempted to search on a property the backend does not
       * support, you should simply return 0 results.
       *
       * You can also just return 0 results if you choose to not support
       * searching at all, but keep in mind that this may stop certain features
       * from working.
       *
       * @param string $prefixPath
       * @param array $searchProperties
       * @return array
       */
      function searchPrincipals($prefixPath, array $searchProperties);
  
      /**
       * Returns the list of members for a group-principal
       *
       * @param string $principal
       * @return array
       */
      function getGroupMemberSet($principal);
  
      /**
       * Returns the list of groups a principal is a member of
       *
       * @param string $principal
       * @return array
       */
      function getGroupMembership($principal);
  
      /**
       * Updates the list of group members for a group principal.
       *
       * The principals should be passed as a list of uri's.
       *
       * @param string $principal
       * @param array $members
       * @return void
       */
      function setGroupMemberSet($principal, array $members);
  
  }