system/libraries/ORM_Tree.php

   1 <?php defined('SYSPATH') OR die('No direct access allowed.');
   2 /**
   3  * Object Relational Mapping (ORM) "tree" extension. Allows ORM objects to act
   4  * as trees, with parents and children.
   5  *
   6  * $Id: ORM_Tree.php 3917 2009-01-21 03:06:22Z zombor $
   7  *
   8  * @package    ORM
   9  * @author     Kohana Team
  10  * @copyright  (c) 2007-2008 Kohana Team
  11  * @license    http://kohanaphp.com/license.html
  12  */
  13 class ORM_Tree extends ORM {
  14
  15         // Name of the child
  16         protected $children;
  17
  18         // Parent keyword name
  19         protected $parent_key = 'parent_id';
  20
  21         /**
  22          * Overload ORM::__get to support "parent" and "children" properties.
  23          *
  24          * @param   string  column name
  25          * @return  mixed
  26          */
  27         public function __get($column)
  28         {
  29                 if ($column === 'parent')
  30                 {
  31                         if (empty($this->related[$column]))
  32                         {
  33                                 // Load child model
  34                                 $model = ORM::factory(inflector::singular($this->children));
  35
  36                                 if (array_key_exists($this->parent_key, $this->object))
  37                                 {
  38                                         // Find children of this parent
  39                                         $model->where($model->primary_key, $this->object[$this->parent_key])->find();
  40                                 }
  41
  42                                 $this->related[$column] = $model;
  43                         }
  44
  45                         return $this->related[$column];
  46                 }
  47                 elseif ($column === 'children')
  48                 {
  49                         if (empty($this->related[$column]))
  50                         {
  51                                 $model = ORM::factory(inflector::singular($this->children));
  52
  53                                 if ($this->children === $this->table_name)
  54                                 {
  55                                         // Load children within this table
  56                                         $this->related[$column] = $model
  57                                                 ->where($this->parent_key, $this->object[$this->primary_key])
  58                                                 ->find_all();
  59                                 }
  60                                 else
  61                                 {
  62                                         // Find first selection of children
  63                                         $this->related[$column] = $model
  64                                                 ->where($this->foreign_key(), $this->object[$this->primary_key])
  65                                                 ->where($this->parent_key, NULL)
  66                                                 ->find_all();
  67                                 }
  68                         }
  69
  70                         return $this->related[$column];
  71                 }
  72
  73                 return parent::__get($column);
  74         }
  75
  76 } // End ORM Tree