<?php

namespace Sabre\DAVACL\PrincipalBackend;

/**
 * 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.
 *
 * @copyright Copyright (C) 2007-2015 fruux GmbH (https://fruux.com/).
 * @author Evert Pot (http://evertpot.com/)
 * @license http://sabre.io/license/ Modified BSD License
 */
interface BackendInterface {

    /**
     * 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);

}
