Simple Enum class

Enum.class.php

<?php

class Enum
{

	private $enumsList = array();
	private $reverseList = array();

	public function __construct(array $enums)
	{

		$this->addEnums($enums);

	}

	public function reverse($value)
	{

		unset($this->reverseList);
		$this->reverseList = array();

		if($value != 0){

			while($value > 0)
			{

				$lastNearestLowerEntry = $this->nearestLowerEntry($value);
				$this->reverseList[] = $lastNearestLowerEntry['name'];
				$value -= $lastNearestLowerEntry['value'];

			}


			return $this->reverseList;

		}
		else
		{

			return null;

		}

	}

	private function nearestLowerEntry($value)
	{

		$lastEntry = $this->enumsList[0];

		foreach($this->enumsList as $key=>$data)
		{

			if($data['value'] > $value && $lastEntry['value'] < $value)
			{

				return $lastEntry;

			}
			else if($value > $data['value'] && !isset($this->enumsList[$key + 1]) OR $data['value'] == $value)
			{

				return $data;

			}

			$lastEntry = $data;

		}

	}

	private function addEnums(array $enums)
	{

		$biggestPowOf2Value = -1;

		foreach($enums as $data)
		{

			$this->enumsList[] = array(
				'name' => $data,
				'value' => pow(2, $biggestPowOf2Value + 1),
			);

			$biggestPowOf2Value ++;

		}
	}

	private function getPowOf2($entry)
	{
		if(is_int($entry)){

			$number = 0;
			$powOf2 = -1;

			while($number < $entry)
			{

				$powOf2 ++;
				$number = pow(2, $powOf2);

			}

			return $powOf2;
		}

	}

}

Example.php

<?php
require_once('Enum.class.php');

// example with a colors of object

$characteristics = new Enum(array('blue', 'red', 'green'));

// Value of blue = 2^0 = 1
// Value of red = 2^1 = 2
// Value of green = 2^2 = 4

// If my object is blue and red his value is 3

$characteristicsOfMyObject = $characteristics->reverse(3); // return array

echo 'Colors of a object with a value equal to 3 : ';

foreach($characteristicsOfMyObject as $data) // writte red, blue
{

	echo '<br/>- '.$data;

}

// If my object is blue and red his value is 7

$characteristicsOfMyObject = $characteristics->reverse(7); // return array

echo '<br/> <br/>Colors of a object with a value equal to 7 : ';

foreach($characteristicsOfMyObject as $data) // writte green, red, blue
{

	echo '<br/>- '.$data;

}