CRM/Contact/BAO/GroupNestingCache.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 4.3                                                |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2013                                |
   7  +--------------------------------------------------------------------+
   8  | This file is a part of CiviCRM.                                    |
   9  |                                                                    |
  10  | CiviCRM is free software; you can copy, modify, and distribute it  |
  11  | under the terms of the GNU Affero General Public License           |
  12  | Version 3, 19 November 2007 and the CiviCRM Licensing Exception.   |
  13  |                                                                    |
  14  | CiviCRM is distributed in the hope that it will be useful, but     |
  15  | WITHOUT ANY WARRANTY; without even the implied warranty of         |
  16  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               |
  17  | See the GNU Affero General Public License for more details.        |
  18  |                                                                    |
  19  | You should have received a copy of the GNU Affero General Public   |
  20  | License and the CiviCRM Licensing Exception along                  |
  21  | with this program; if not, contact CiviCRM LLC                     |
  22  | at info[AT]civicrm[DOT]org. If you have questions about the        |
  23  | GNU Affero General Public License or the licensing of CiviCRM,     |
  24  | see the CiviCRM license FAQ at http://civicrm.org/licensing        |
  25  +--------------------------------------------------------------------+
  26 */
  27
  28 /**
  29  *
  30  * @package CRM
  31  * @copyright CiviCRM LLC (c) 2004-2013
  32  * $Id$
  33  *
  34  */
  35 class CRM_Contact_BAO_GroupNestingCache {
  36   static public function update() {
  37     // lets build the tree in memory first
  38
  39     $sql = "
  40 SELECT n.child_group_id  as child ,
  41        n.parent_group_id as parent
  42 FROM   civicrm_group_nesting n,
  43        civicrm_group gc,
  44        civicrm_group gp
  45 WHERE  n.child_group_id  = gc.id
  46   AND  n.parent_group_id = gp.id
  47 ";
  48
  49     $dao = CRM_Core_DAO::executeQuery($sql);
  50
  51     $tree = array();
  52     while ($dao->fetch()) {
  53       if (!array_key_exists($dao->child, $tree)) {
  54         $tree[$dao->child] = array('children' => array(),
  55           'parents' => array(),
  56         );
  57       }
  58
  59       if (!array_key_exists($dao->parent, $tree)) {
  60         $tree[$dao->parent] = array('children' => array(),
  61           'parents' => array(),
  62         );
  63       }
  64
  65       $tree[$dao->child]['parents'][] = $dao->parent;
  66       $tree[$dao->parent]['children'][] = $dao->child;
  67     }
  68
  69     if (self::checkCyclicGraph($tree)) {
  70       CRM_Core_Error::fatal(ts('We detected a cycle which we cant handle. aborting'));
  71     }
  72
  73     // first reset the current cache entries
  74     $sql = "
  75 UPDATE civicrm_group
  76 SET    parents  = null,
  77        children = null
  78 ";
  79     CRM_Core_DAO::executeQuery($sql);
  80
  81     $values = array();
  82     foreach (array_keys($tree) as $id) {
  83       $parents  = implode(',', $tree[$id]['parents']);
  84       $children = implode(',', $tree[$id]['children']);
  85       $parents  = $parents == NULL ? 'null' : "'$parents'";
  86       $children = $children == NULL ? 'null' : "'$children'";
  87       $sql      = "
  88 UPDATE civicrm_group
  89 SET    parents  = $parents ,
  90        children = $children
  91 WHERE  id = $id
  92 ";
  93       CRM_Core_DAO::executeQuery($sql);
  94     }
  95
  96     // this tree stuff is quite useful, so lets store it in the cache
  97     CRM_Core_BAO_Cache::setItem($tree, 'contact groups', 'nestable tree hierarchy');
  98   }
  99
 100   static function checkCyclicGraph(&$tree) {
 101     // lets keep this simple, we should probably use a graph algoritm here at some stage
 102
 103     // foreach group that has a parent or a child, ensure that
 104     // the ancestors and descendants dont intersect
 105     foreach ($tree as $id => $dontCare) {
 106       if (self::isCyclic($tree, $id)) {
 107         return TRUE;
 108       }
 109     }
 110
 111     return FALSE;
 112   }
 113
 114   static function isCyclic(&$tree, $id) {
 115     $parents = $children = array();
 116     self::getAll($parent, $tree, $id, 'parents');
 117     self::getAll($child, $tree, $id, 'children');
 118
 119     $one = array_intersect($parents, $children);
 120     $two = array_intersect($children, $parents);
 121     if (!empty($one) ||
 122       !empty($two)
 123     ) {
 124       CRM_Core_Error::debug($id, $tree);
 125       CRM_Core_Error::debug($id, $one);
 126       CRM_Core_Error::debug($id, $two);
 127       return TRUE;
 128     }
 129     return FALSE;
 130   }
 131
 132   static function getPotentialCandidates($id, &$groups) {
 133     $tree = CRM_Core_BAO_Cache::getItem('contact groups', 'nestable tree hierarchy');
 134
 135     if ($tree === NULL) {
 136       self::update();
 137       $tree = CRM_Core_BAO_Cache::getItem('contact groups', 'nestable tree hierarchy');
 138     }
 139
 140     $potential = $groups;
 141
 142     // remove all descendants
 143     self::invalidate($potential, $tree, $id, 'children');
 144
 145     // remove all ancestors
 146     self::invalidate($potential, $tree, $id, 'parents');
 147
 148     return array_keys($potential);
 149   }
 150
 151   static function invalidate(&$potential, &$tree, $id, $token) {
 152     unset($potential[$id]);
 153
 154     if (!isset($tree[$id]) ||
 155       empty($tree[$id][$token])
 156     ) {
 157       return;
 158     }
 159
 160     foreach ($tree[$id][$token] as $tokenID) {
 161       self::invalidate($potential, $tree, $tokenID, $token);
 162     }
 163   }
 164
 165   static function getAll(&$all, &$tree, $id, $token) {
 166     // if seen before, dont do anything
 167     if (isset($all[$id])) {
 168       return;
 169     }
 170
 171     $all[$id] = 1;
 172     if (!isset($tree[$id]) ||
 173       empty($tree[$id][$token])
 174     ) {
 175       return;
 176     }
 177
 178     foreach ($tree[$id][$token] as $tokenID) {
 179       self::getAll($all, $tree, $tokenID, $token);
 180     }
 181   }
 182
 183   static function json() {
 184     $tree = CRM_Core_BAO_Cache::getItem('contact groups', 'nestable tree hierarchy');
 185
 186     if ($tree === NULL) {
 187       self::update();
 188       $tree = CRM_Core_BAO_Cache::getItem('contact groups', 'nestable tree hierarchy');
 189     }
 190
 191     // get all the groups
 192     $groups = CRM_Core_PseudoConstant::group();
 193
 194     foreach ($groups as $id => $name) {
 195       $string = "id:'$id', name:'$name'";
 196       if (isset($tree[$id])) {
 197         $children = array();
 198         if (!empty($tree[$id]['children'])) {
 199           foreach ($tree[$id]['children'] as $child) {
 200             $children[] = "{_reference:'$child'}";
 201           }
 202           $children = implode(',', $children);
 203           $string .= ", children:[$children]";
 204           if (empty($tree[$id]['parents'])) {
 205             $string .= ", type:'rootGroup'";
 206           }
 207           else {
 208             $string .= ", type:'middleGroup'";
 209           }
 210         }
 211         else {
 212           $string .= ", type:'leafGroup'";
 213         }
 214       }
 215       else {
 216         $string .= ", children:[], type:'rootGroup'";
 217       }
 218       $values[] = "{ $string }";
 219     }
 220
 221     $items = implode(",\n", $values);
 222     $json = "{
 223   identifier:'id',
 224   label:'name',
 225   items:[ $items ]
 226 }";
 227     return $json;
 228   }
 229 }
 230