<?php
class RecursiveArrayObject extends ArrayObject {

	public function getIterator () {
		return new RecursiveArrayIterator ($this);
	}
}

class myFilter extends FilterIterator  {

	private $oIt = null;
	private $mFilter = null;

    public function __construct ($oIt, $mFilter = null) {
        parent::__construct ($oIt);
        $this -> oIt = $oIt;
        $this -> mFilter = $mFilter;
    }

    public function accept () {
        if (is_string ($this -> mFilter) && ($this -> oIt -> current () !== $this -> mFilter)) {
        	return false;
        }
        return true;
    }

}

abstract class oCore implements IteratorAggregate {

	private static $aRef = array ();
	private $mFilter = null;
	private $aCanBeSet = array (
	'FILTER'
	);

	public function __construct () {
		if (array_key_exists ($this -> iOpId, self::$aRef)) {
			throw new Exception ('OP '.$this -> iOpId.' has already been instanciated');
		}
		self::$aRef[$this -> iOpId] = $this -> aMods;
	}


	public function getIterator () {
		if (!is_null ($this -> mFilter)) {
			if (is_string ($this -> mFilter)) {
				return new myFilter (new RecursiveIteratorIterator (new RecursiveArrayObject(self::$aRef), RecursiveIteratorIterator::SELF_FIRST), $this -> mFilter);
			}
			if (is_int ($this -> mFilter)) {
				if (!isset (self::$aRef[$this -> mFilter])) {
					throw new Exception ($this -> mFilter.' is not a valid OP');
				}
				return new RecursiveIteratorIterator (new RecursiveArrayObject(self::$aRef[$this -> mFilter]), RecursiveIteratorIterator::SELF_FIRST);
			}
		}
		return new RecursiveIteratorIterator (new RecursiveArrayObject(self::$aRef), RecursiveIteratorIterator::SELF_FIRST);
	}

	public function __destruct() {
		self::$aRef[$this -> iOpId] = null;
	}

	public function __set ($sProp, $mVal) {
		if (!in_array ($sProp, $this -> aCanBeSet)) {
			throw new Exception ($sProp.' is not a settable property');
		}
		switch ($sProp) {
			case 'FILTER' :
				$this -> mFilter = $mVal;
				break;
		}
	}

}

class oSystem extends oCore {

	private static $oInstance = null;

	public function __construct () {

	}

	public static function getInstance () {
		if (!isset(self::$oInstance)) {
			self::$oInstance = new self;
		}
		return self::$oInstance;
	}

	public function __destruct () {
		self::$oInstance = null;
	}

}

class oOp extends oCore {

	protected $aMods = array ();
	protected $iOpId;

	public function __construct ($iOpId, array $aMods) {
		$this -> iOpId = $iOpId;
		$this -> aMods = $aMods;
		parent::__construct ();
	}
}
/**
 * EXEMPLES
 */
$a = new oOp (5489, array ('mod1','mod2','mod3'));
$b = new oOp (5580, array ('mod2','mod5','mod6'));

$oSys = new oSystem;

echo 'Traverse les OP à la recherche de tous les mods<br />';
foreach ($oSys as $sK => $mV) {
	echo $sK, ' => ', $mV, '<br />';
}

echo '<br />Traverse les OP à la recherche d\'un mod<br />';
$oSys -> FILTER = 'mod2';
foreach ($oSys as $sK => $mV) {
	echo $sK, ' => ', $mV, '<br />';
}

echo '<br />Cherche les mods d\'1 OP<br />';
$oSys -> FILTER = 5580;
foreach ($oSys as $sK => $mV) {
	echo $sK, ' => ', $mV, '<br />';
}
?>