<?php
// $Id: tree.php,v 1.12 2003/09/26 10:17:45 okazu Exp $
//  ------------------------------------------------------------------------ //
//                XOOPS - PHP Content Management System                      //
//                    Copyright (c) 2000 XOOPS.org                           //
//                       <http://www.xoops.org/>                             //
//  ------------------------------------------------------------------------ //
//  This program is free software; you can redistribute it and/or modify     //
//  it under the terms of the GNU General Public License as published by     //
//  the Free Software Foundation; either version 2 of the License, or        //
//  (at your option) any later version.                                      //
//                                                                           //
//  You may not change or alter any portion of this comment or credits       //
//  of supporting developers from this source code or any supporting         //
//  source code which is considered copyrighted (c) material of the          //
//  original comment or credit authors.                                      //
//                                                                           //
//  This program is distributed in the hope that it will be useful,          //
//  but WITHOUT ANY WARRANTY; without even the implied warranty of           //
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            //
//  GNU General Public License for more details.                             //
//                                                                           //
//  You should have received a copy of the GNU General Public License        //
//  along with this program; if not, write to the Free Software              //
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA //
//  ------------------------------------------------------------------------ //
// Author: Kazumi Ono (AKA onokazu)                                          //
// URL: http://www.xoops.org/ http://jp.xoops.org/  http://www.myweb.ne.jp/  //
// Project: The XOOPS Project (http://www.xoops.org/)                        //
// ------------------------------------------------------------------------- //

/**
 * A tree structures with {@link XoopsObject}s as nodes
 *
 * @package		kernel
 * @subpackage	core
 *
 * @author		Kazumi Ono 	<onokazu@xoops.org>
 * @copyright	(c) 2000-2003 The Xoops Project - www.xoops.org
 */
class XoopsObjectTree {

	/**#@+
	 * @access	private
	 */
	var $_parentId;
	var $_myId;
	var $_rootId = null;
	var $_tree = array();
	var $_objects;
    /**#@-*/

	/**
	 * Constructor
	 * 
	 * @param   array   $objectArr  Array of {@link XoopsObject}s 
	 * @param   string     $myId       field name of object ID
	 * @param   string     $parentId   field name of parent object ID
	 * @param   string     $rootId     field name of root object ID
	 **/
	function XoopsObjectTree(&$objectArr, $myId, $parentId, $rootId = null)
	{
		$this->_objects =& $objectArr;
		$this->_myId = $myId;
		$this->_parentId = $parentId;
		if (isset($rootId)) {
			$this->_rootId = $rootId;
		}
		$this->_initialize();
	}

	/**
	 * Initialize the object
	 * 
	 * @access	private
	 **/
	function _initialize()
	{
		foreach (array_keys($this->_objects) as $i) {
            $key1 = $this->_objects[$i]->getVar($this->_myId);
            $this->_tree[$key1]['obj'] =& $this->_objects[$i];
            $key2 = $this->_objects[$i]->getVar($this->_parentId);
            $this->_tree[$key1]['parent'] = $key2;
            $this->_tree[$key2]['child'][] = $key1;
			if (isset($this->_rootId)) {
            	$this->_tree[$key1]['root'] = $this->_objects[$i]->getVar($this->_rootId);
			}
        }
	}

	/**
	 * Get the tree
	 * 
	 * @return  array   Associative array comprising the tree 
	 **/
	function &getTree()
	{
		return $this->_tree;
	}

	/**
	 * returns an object from the tree specified by its id
	 * 
	 * @param   string  $key    ID of the object to retrieve
     * @return  object  Object within the tree
	 **/
	function &getByKey($key)
	{
		return $this->_tree[$key]['obj'];
	}

	/**
	 * returns an array of all the first child object of an object specified by its id
	 * 
	 * @param   string  $key    ID of the parent object
	 * @return  array   Array of children of the parent
	 **/
	function &getFirstChild($key)
	{
		$ret = array();
		if (isset($this->_tree[$key]['child'])) {
			foreach ($this->_tree[$key]['child'] as $childkey) {
				$ret[$childkey] =& $this->_tree[$childkey]['obj'];
			}
		}
		return $ret;
	}

	/**
	 * returns an array of all child objects of an object specified by its id
	 * 
	 * @param   string     $key    ID of the parent
	 * @param   array   $ret    (Empty when called from client) Array of children from previous recursions.
	 * @return  array   Array of child nodes.
	 **/
	function &getAllChild($key, $ret = array())
	{
		if (isset($this->_tree[$key]['child'])) {
			foreach ($this->_tree[$key]['child'] as $childkey) {
				$ret[$childkey] =& $this->_tree[$childkey]['obj'];
				$children =& $this->getAllChild($childkey, $ret);
				foreach (array_keys($children) as $newkey) {
					$ret[$newkey] =& $children[$newkey];
				}
			}
		}
		return $ret;
	}

	/**
     * returns an array of all parent objects.
     * the key of returned array represents how many levels up from the specified object
	 * 
	 * @param   string     $key    ID of the child object
	 * @param   array   $ret    (empty when called from outside) Result from previous recursions
	 * @param   int $uplevel (empty when called from outside) level of recursion
	 * @return  array   Array of parent nodes. 
	 **/
	function &getAllParent($key, $ret = array(), $uplevel = 1)
	{
		if (isset($this->_tree[$key]['parent']) && isset($this->_tree[$this->_tree[$key]['parent']]['obj'])) {
			$ret[$uplevel] =& $this->_tree[$this->_tree[$key]['parent']]['obj'];
			$parents =& $this->getAllParent($this->_tree[$key]['parent'], $ret, $uplevel+1);
			foreach (array_keys($parents) as $newkey) {
				$ret[$newkey] =& $parents[$newkey];
			}
		}
		return $ret;
	}

	/**
	 * Make options for a select box from
	 * 
	 * @param   string  $fieldName   Name of the member variable from the
     *  node objects that should be used as the title for the options.
	 * @param   string  $selected    Value to display as selected
	 * @param   int $key         ID of the object to display as the root of select options
     * @param   string  $ret         (reference to a string when called from outside) Result from previous recursions
	 * @param   string  $prefix_orig  String to indent items at deeper levels
	 * @param   string  $prefix_curr  String to indent the current item
	 * @return
     * 
     * @access	private 
	 **/
	function _makeSelBoxOptions($fieldName, $selected, $key, &$ret, $prefix_orig, $prefix_curr = '')
	{
        if ($key > 0) {
            $value = $this->_tree[$key]['obj']->getVar($this->_myId);
            $ret .= '<option value="'.$value.'"';
			if ($value == $selected) {
				$ret .= ' selected="selected"';
			}
			$ret .= '>'.$prefix_curr.$this->_tree[$key]['obj']->getVar($fieldName).'</option>';
            $prefix_curr .= $prefix_orig;
        }
        if (isset($this->_tree[$key]['child']) && !empty($this->_tree[$key]['child'])) {
            foreach ($this->_tree[$key]['child'] as $childkey) {
                $this->_makeSelBoxOptions($fieldName, $selected, $childkey, $ret, $prefix_orig, $prefix_curr);
            }
        }
	}

	/**
	 * Make a select box with options from the tree
	 * 
	 * @param   string  $name            Name of the select box
	 * @param   string  $fieldName       Name of the member variable from the
     *  node objects that should be used as the title for the options.  
	 * @param   string  $prefix          String to indent deeper levels
	 * @param   string  $selected        Value to display as selected
	 * @param   bool    $addEmptyOption  Set TRUE to add an empty option with value "0" at the top of the hierarchy
	 * @param   integer $key             ID of the object to display as the root of select options
	 * @return  string  HTML select box
	 **/
	function &makeSelBox($name, $fieldName, $prefix='-', $selected='', $addEmptyOption = false, $key=0)
    {
        $ret = '<select name='.$name.'>';
        if (false != $addEmptyOption) {
            $ret .= '<option value="0"></option>';
        }
        $this->_makeSelBoxOptions($fieldName, $selected, $key, $ret, $prefix);
        return $ret.'</select>';
    }


}
?>