1<?php
2/**
3 * pfccontainerinterface.class.php
4 *
5 * Copyright © 2006 Stephane Gully <stephane.gully@gmail.com>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, 51 Franklin St, Fifth Floor,
20 * Boston, MA  02110-1301  USA
21 */
22
23/**
24 * pfcContainerInterface is an interface implemented by pfcContainer and each pfcContainer concrete isntances (File,Mysql...)
25 *
26 * @author Stephane Gully <stephane.gully@gmail.com>
27 * @abstract
28 */
29class pfcContainerInterface
30{
31  function pfcContainerInterface() { }
32  function getDefaultConfig()      { return array(); }
33  function init(&$c)               { return array(); }
34
35  /**
36   * Write a meta data value identified by a group / subgroup / leaf [with a value]
37   * As an example in the default file container this  arborescent structure is modelised by simple directories
38   * group1/subgroup1/leaf1
39   *                 /leaf2
40   *       /subgroup2/...
41   * Each leaf can contain or not a value.
42   * However each leaf and each group/subgroup must store the lastmodified time (timestamp).
43   * @param $group root arborescent element
44   * @param $subgroup is the root first child which contains leafs
45   * @param $leaf is the only element which can contain values
46   * @param $leafvalue NULL means the leaf will not contain any values
47   * @return 1 if the old leaf has been overwritten, 0 if a new leaf has been created
48   */
49  function setMeta($group, $subgroup, $leaf, $leafvalue = NULL)
50  { die(_pfc("%s must be implemented", get_class($this)."::".__FUNCTION__)); }
51
52
53  /**
54   * Read meta data identified by a group [/ subgroup [/ leaf]]
55   * @param $group is mandatory, it's the arborescence's root
56   * @param $subgroup if null then the subgroup list names are returned
57   * @param $leaf if null then the leaf names are returned
58   * @param $withleafvalue if set to true the leaf value will be returned
59   * @return array which contains two subarray 'timestamp' and 'value'
60   */
61  function getMeta($group, $subgroup = null, $leaf = null, $withleafvalue = false)
62  { die(_pfc("%s must be implemented", get_class($this)."::".__FUNCTION__)); }
63
64
65  /**
66   * Remove a meta data or a group of metadata
67   * @param $group if null then it will remove all the possible groups (all the created metadata)
68   * @param $subgroup if null then it will remove the $group's childs (all the subgroup contained by $group)
69   * @param $leaf if null then it will remove all the $subgroup's childs (all the leafs contained by $subgroup)
70   * @return true on success, false on error
71   */
72  function rmMeta($group, $subgroup = null, $leaf = null)
73  { die(_pfc("%s must be implemented", get_class($this)."::".__FUNCTION__)); }
74
75
76  /**
77   * In the default File container: used to encode UTF8 strings to ASCII filenames
78   * This method can be overridden by the concrete container
79   */
80  function encode($str)
81  {
82    return $str;
83  }
84
85  /**
86   * In the default File container: used to decode ASCII filenames to UTF8 strings
87   * This method can be overridden by the concrete container
88   */
89  function decode($str)
90  {
91    return $str;
92  }
93}
94
95?>