doctrine2/draft/Tree/NestedSet.php

<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.phpdoctrine.com>.
 */
/**
 * Doctrine_Tree_NestedSet
 *
 * @package     Doctrine
 * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @category    Object Relational Mapping
 * @link        www.phpdoctrine.com
 * @since       1.0
 * @version     $Revision$
 * @author      Joe Simms <joe.simms@websites4.com>
 */
class Doctrine_Tree_NestedSet extends Doctrine_Tree implements Doctrine_Tree_Interface
{
	/**
	 * used to define table attributes required for the NestetSet implementation
	 * adds lft and rgt columns for corresponding left and right values
	 *			
	 */ 
  public function setTableDefinition()
  {
    $this->table->setColumn("lft","integer",11);
    $this->table->setColumn("rgt","integer",11);
  }

	/**
	 * creates root node from given record or from a new record
	 *
	 * @param object $record		instance of Doctrine_Record				
	 */ 
  public function createRoot(Doctrine_Record $record = null)
  {
    if(!$record)
    {
      $record = $this->table->create();
    }
    
    $record->set('lft', '1');
    $record->set('rgt', '2');
    $record->save();
    
    return $record;
  }

	/**
	 * returns root node
	 *
	 * @return object $record		instance of Doctrine_Record				
	 */  
  public function findRoot()
  {
    $q = $this->table->createQuery();
    $root = $q->where('lft = ?', 1)
                ->execute()->getFirst();
    
    // if no record is returned, create record
    if(!$root)
    {
      $root = $this->table->create();
    }

    // set level to prevent additional query to determine level
    $root->getNode()->setLevel(0);

    return $root;
  }
	/**
	 * optimised method to returns iterator for traversal of the entire tree from root
	 * 
	 * @param array $options		  options		
	 * @return object $iterator		instance of Doctrine_Node_NestedSet_PreOrderIterator			
	 */  
  public function fetchTree($options = array())
  {
    // fetch tree
    $q = $this->table->createQuery();
    
    $tree = $q->where('lft >= ?', 1)
              ->orderBy('lft asc')
              ->execute();
              
    $root = $tree->getFirst();

    // if no record is returned, create record
    if(!$root)
    {
      $root = $this->table->create();
    }

    if($root->exists())
    {
      // set level to prevent additional query
      $root->getNode()->setLevel(0);

      // default to include root node
      $options = array_merge(array('include_record'=>true), $options);
      
      // remove root node from collection if not required
      if($options['include_record'] == false)
        $tree->remove(0);

      // set collection for iterator        
      $options['collection'] = $tree;

      return $root->getNode()->traverse('Pre', $options);      
    }
  }
	/**
	 * optimised method that returns iterator for traversal of the tree from the given record primary key
	 * 
	 * @param mixed $pk		        primary key as used by table::find() to locate node to traverse tree from
	 * @param array $options		  options		
	 * @return iterator		instance of Doctrine_Node_<Implementation>_PreOrderIterator					
	 */   
  public function fetchBranch($pk, $options = array())
  {
    $record = $this->table->find($pk);
    if($record->exists())
    {
      $options = array_merge(array('include_record'=>true), $options);
      return $record->getNode()->traverse('Pre', $options);      
    }
  }
}