Chris@0: <?php
Chris@0: /**
Chris@0:  * Zend Framework (http://framework.zend.com/)
Chris@0:  *
Chris@0:  * @link      http://github.com/zendframework/zf2 for the canonical source repository
Chris@0:  * @copyright Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
Chris@0:  * @license   http://framework.zend.com/license/new-bsd New BSD License
Chris@0:  */
Chris@0: 
Chris@0: namespace Zend\Stdlib;
Chris@0: 
Chris@0: use Serializable;
Chris@0: 
Chris@0: /**
Chris@0:  * Serializable version of SplPriorityQueue
Chris@0:  *
Chris@0:  * Also, provides predictable heap order for datums added with the same priority
Chris@0:  * (i.e., they will be emitted in the same order they are enqueued).
Chris@0:  */
Chris@0: class SplPriorityQueue extends \SplPriorityQueue implements Serializable
Chris@0: {
Chris@0:     /**
Chris@0:      * @var int Seed used to ensure queue order for items of the same priority
Chris@0:      */
Chris@0:     protected $serial = PHP_INT_MAX;
Chris@0: 
Chris@0:     /**
Chris@0:      * Insert a value with a given priority
Chris@0:      *
Chris@0:      * Utilizes {@var $serial} to ensure that values of equal priority are
Chris@0:      * emitted in the same order in which they are inserted.
Chris@0:      *
Chris@0:      * @param  mixed $datum
Chris@0:      * @param  mixed $priority
Chris@0:      * @return void
Chris@0:      */
Chris@0:     public function insert($datum, $priority)
Chris@0:     {
Chris@12:         if (! is_array($priority)) {
Chris@0:             $priority = [$priority, $this->serial--];
Chris@0:         }
Chris@0:         parent::insert($datum, $priority);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Serialize to an array
Chris@0:      *
Chris@0:      * Array will be priority => data pairs
Chris@0:      *
Chris@0:      * @return array
Chris@0:      */
Chris@0:     public function toArray()
Chris@0:     {
Chris@0:         $array = [];
Chris@0:         foreach (clone $this as $item) {
Chris@0:             $array[] = $item;
Chris@0:         }
Chris@0:         return $array;
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Serialize
Chris@0:      *
Chris@0:      * @return string
Chris@0:      */
Chris@0:     public function serialize()
Chris@0:     {
Chris@0:         $clone = clone $this;
Chris@0:         $clone->setExtractFlags(self::EXTR_BOTH);
Chris@0: 
Chris@0:         $data = [];
Chris@0:         foreach ($clone as $item) {
Chris@0:             $data[] = $item;
Chris@0:         }
Chris@0: 
Chris@0:         return serialize($data);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Deserialize
Chris@0:      *
Chris@0:      * @param  string $data
Chris@0:      * @return void
Chris@0:      */
Chris@0:     public function unserialize($data)
Chris@0:     {
Chris@17:         $this->serial = PHP_INT_MAX;
Chris@0:         foreach (unserialize($data) as $item) {
Chris@17:             $this->serial--;
Chris@0:             $this->insert($item['data'], $item['priority']);
Chris@0:         }
Chris@0:     }
Chris@0: }