这个js文件怎么转换成php文件，到了for后面我就不会了😓

function login(a)
{
return this.securityEncode(a,
"RDpbLfCPsJZ7fiv",
"yLwVl0zKqws7LgKPRQ84Mdt708T1qQ3Ha7xv3H7NyU84p21BriUWBU43odz3iP4rBL3cD02KZciXTysVXiV8ngg6vL48rPJyAUw0HurW20xqxv9aYb4M9wK1Ae0wlro510qXeU07kV57fQMc8L6aLgMLwygtc0F10a0Dg70TOoouyFhdysuRMO51yY5ZlOZZLEal1h0t9YQW0Ko7oBwmCAHoic4HYbUyVeU3sfQ1xtXcPcf1aT303wAQhv66qzW")
};
this.securityEncode=function(a,c,b)
{
var d="",
f,e,g,h,k=187,
l=187;
e=a.length;
g=c.length;
h=b.length;
f=e > g ? e : g;
    for(var m=0 ; m<f ; m++) l = k = 187,
    m >= e ? l = c.charCodeAt(m):
    m >= g ? k=a.charCodeAt(m):
        (
        k=a.charCodeAt(m)
        ,l=c.charCodeAt(m)
        ),
    d += b.charAt((k ^ l) % h);
    return d
};

let r = login('zh955');
console.log(r);

完全看不懂写的是啥

<?php
class L
{
    private $_aaaaaa = '';
    private $_bbbbbb = '';

    public function __construct($aaaaa,$bbbbb)
    {
        $this->_aaaaaa = $aaaaa;
        $this->_bbbbbb = $bbbbb;
    }

    public function login($a)
    {
        return $this->securityEncode($a,$this->_aaaaaa,$this->_bbbbbb);
    }

    public function securityEncode($a,$b,$c)
    {
        $d='';
        $f=$e=$g=$h=$k=$l=187;

        $e=strlen($a);
        $g=strlen($c);
        $h=strlen($b);
        $f=$e>$g?$e:$g;

        for($m=0; $m<$f; $m++)
        {
            $l=$k=187;
            if($m>$e)
            {
                $l=ord($c[$m]);
            }
            else
            {
                if($m>=$g)
                {
                    $k=ord($a[$m]);
                }
                else
                {
                    $k=ord($a[$m]);
                    $l=ord($c[$m]);
                }
            }
            $d .= $b[($k^$l)%$h];
        }
        return $d;
    }
}

$a = 'RDpbLfCPsJZ7fiv';
$b = 'yLwVl0zKqws7LgKPRQ84Mdt708T1qQ3Ha7xv3H7NyU84p21BriUWBU43odz3iP4rBL3cD02KZciXTysVXiV8ngg6vL48rPJyAUw0HurW20xqxv9aYb4M9wK1Ae0wlro510qXeU07kV57fQMc8L6aLgMLwygtc0F10a0Dg70TOoouyFhdysuRMO51yY5ZlOZZLEal1h0t9YQW0Ko7oBwmCAHoic4HYbUyVeU3sfQ1xtXcPcf1aT303wAQhv66qzW';

$l = new L($a, $b);
$r = $l->login('zh955');
var_dump($r);