<?php

abstract class User
{
    protected $username;
    protected $password;

    abstract function checkLogin($username, $password);

    abstract function setLogin($username);

    abstract function setPassword($password);

    final public function login($username, $password){
        return $this->checkLogin($username,$password);
    }
}

class Client extends User {

    function checkLogin($username, $password)
    {
        if ($password != $this->password) return false;
        if ($username != $this->username) return false;
        return true;
    }

    function setLogin($username)
    {
        $this->username = $username;
    }

    function setPassword($password)
    {
        if ( strlen($password) < 8 ) return false;
        $this->password = $password;
    }
}

class Admin extends User {

    private $ip;

    function checkLogin($username, $password)
    {
        $this->ip = "192.168.33.22";
        if ($password != $this->password) return false;
        if ($username != $this->username) return false;
        return true;
    }

    function setLogin($username)
    {
        $this->username = $username;
    }

    function setPassword($password)
    {
        if ( strlen($password) < 9 ) return false;
        $this->password = $password;
    }
}

$admin = new Admin();
$admin->setLogin("admin");
$admin->setPassword("testowiecsda");
if ($admin->login("admin","testowiecs")){
    echo "brawo";
}