<?php
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 3.0.0
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\Collection\Iterator;
use Cake\Collection\CollectionTrait;
use RecursiveIteratorIterator;
/**
* Iterator for flattening elements in a tree structure while adding some
* visual markers for their relative position in the tree
*/
class TreePrinter extends RecursiveIteratorIterator
{
use CollectionTrait;
/**
* A callable to generate the iteration key
*
* @var callable
*/
protected $_key;
/**
* A callable to extract the display value
*
* @var callable
*/
protected $_value;
/**
* Cached value for the current iteration element
*
* @var mixed
*/
protected $_current;
/**
* The string to use for prefixing the values according to their depth in the tree.
*
* @var string
*/
protected $_spacer;
/**
* Constructor
*
* @param \RecursiveIterator $items The iterator to flatten.
* @param string|callable $valuePath The property to extract or a callable to return
* the display value.
* @param string|callable $keyPath The property to use as iteration key or a
* callable returning the key value.
* @param string $spacer The string to use for prefixing the values according to
* their depth in the tree.
* @param int $mode Iterator mode.
*/
public function __construct($items, $valuePath, $keyPath, $spacer, $mode = RecursiveIteratorIterator::SELF_FIRST)
{
parent::__construct($items, $mode);
$this->_value = $this->_propertyExtractor($valuePath);
$this->_key = $this->_propertyExtractor($keyPath);
$this->_spacer = $spacer;
}
/**
* Returns the current iteration key
*
* @return mixed
*/
public function key()
{
$extractor = $this->_key;
return $extractor($this->_fetchCurrent(), parent::key(), $this);
}
/**
* Returns the current iteration value
*
* @return string
*/
public function current()
{
$extractor = $this->_value;
$current = $this->_fetchCurrent();
$spacer = str_repeat($this->_spacer, $this->getDepth());
return $spacer . $extractor($current, parent::key(), $this);
}
/**
* Advances the cursor one position
*
* @return void
*/
public function next()
{
parent::next();
$this->_current = null;
}
/**
* Returns the current iteration element and caches its value
*
* @return mixed
*/
protected function _fetchCurrent()
{
if ($this->_current !== null) {
return $this->_current;
}
return $this->_current = parent::current();
}
}