<?php
/**
* Copyright © Magento, Inc. All rights reserved.
* See COPYING.txt for license details.
*/
namespace Magento\Framework\Cache\Frontend\Adapter;

/**
* Adapter for Magento -> Zend cache frontend interfaces
*/
class Zend implements \Magento\Framework\Cache\FrontendInterface
{
/**
* @var \Zend_Cache_Core
*/
protected $_frontend;

/**
* Factory that creates the \Zend_Cache_Cores
*
* @var \Closure
*/
private $frontendFactory;

/**
* The pid that owns the $_frontend object
*
* @var int
*/
private $pid;

/**
* @param \Closure $frontendFactory
*/
public function __construct(\Closure $frontendFactory)
{
$this->frontendFactory = $frontendFactory;
$this->_frontend = $frontendFactory();
$this->pid = getmypid();
}

/**
* {@inheritdoc}
*/
public function test($identifier)
{
return $this->getFrontEnd()->test($this->_unifyId($identifier));
}

/**
* {@inheritdoc}
*/
public function load($identifier)
{
return $this->getFrontEnd()->load($this->_unifyId($identifier));
}

/**
* {@inheritdoc}
*/
public function save($data, $identifier, array $tags = [], $lifeTime = null)
{
return $this->getFrontEnd()->save($data, $this->_unifyId($identifier), $this->_unifyIds($tags), $lifeTime);
}

/**
* {@inheritdoc}
*/
public function remove($identifier)
{
return $this->getFrontEnd()->remove($this->_unifyId($identifier));
}

/**
* {@inheritdoc}
*
* @throws \InvalidArgumentException Exception is thrown when non-supported cleaning mode is specified
* @throws \Zend_Cache_Exception
*/
public function clean($mode = \Zend_Cache::CLEANING_MODE_ALL, array $tags = [])
{
// Cleaning modes 'old' and 'notMatchingTag' are prohibited as a trade off for decoration reliability
if (!in_array(
$mode,
[
\Zend_Cache::CLEANING_MODE_ALL,
\Zend_Cache::CLEANING_MODE_MATCHING_TAG,
\Zend_Cache::CLEANING_MODE_MATCHING_ANY_TAG
]
)
) {
throw new \InvalidArgumentException(
"Magento cache frontend does not support the cleaning mode '{$mode}'."
);
}
return $this->getFrontEnd()->clean($mode, $this->_unifyIds($tags));
}

/**
* {@inheritdoc}
*/
public function getBackend()
{
return $this->getFrontEnd()->getBackend();
}

/**
* {@inheritdoc}
*/
public function getLowLevelFrontend()
{
return $this->getFrontEnd();
}

/**
* Retrieve single unified identifier
*
* @param string $identifier
* @return string
*/
protected function _unifyId($identifier)
{
return strtoupper($identifier);
}

/**
* Retrieve multiple unified identifiers
*
* @param array $ids
* @return array
*/
protected function _unifyIds(array $ids)
{
foreach ($ids as $key => $value) {
$ids[$key] = $this->_unifyId($value);
}
return $ids;
}

/**
* Get frontEnd cache adapter for current pid
*
* @return \Zend_Cache_Core
*/
private function getFrontEnd()
{
if (getmypid() === $this->pid) {
return $this->_frontend;
}
$frontendFactory = $this->frontendFactory;
$this->_frontend = $frontendFactory();
$this->pid = getmypid();
return $this->_frontend;
}
}