Moving from hard-coded to SOLID principles in PHP

Question

I am actually reading theory about clean code and SOLID principles. I know understand well that we should program to an interface and not to an implementation.

So, I actually try to apply those principles to a little part of my code. I would like to have your advice or point of view so I can know if I am going in the good direction. I'll show you my previous code and my actual so you can visualize the evolution.

To start, i had a method in my controller to check some requirements for every step of an order process (4 steps that the user have to follow in the right order => 1 then 2 then 3 and then 4)

This is my old code :

    private function isAuthorizedStep($stepNumber)
    {
        $isStepAccessAuthorized = TRUE;

        switch($stepNumber) {
            case self::ORDER_STEP_TWO: // ORDER_STEP_TWO = 2
                if (!($_SESSION['actualOrderStep'] >= ORDER_STEP_ONE)) {
                    $isStepAccessAuthorized = FALSE;
                }
                break;

            case self::ORDER_STEP_THREE:
                if (!($_SESSION['actualOrderStep'] >= ORDER_STEP_TWO)) {
                    $isStepAccessAuthorized = FALSE;
                }
                break;

            ...
        }

        return $isStepAccessAuthorized;
    }

    public function orderStepTwo()
    {
        if ($this->isAuthorizedStep(self::ORDER_STEP_TWO) {
            return;
        }

        ... // do some stuff

        // after all the verifications: 
        $_SESSION['actualOrderStep'] = ORDER_STEP_TWO
    }

Trying to fit to SOLID principles, I splited my code following this logic:

• Extracting hard-coded logic from controllers to put it in classes (reusability)
• Using Dependency Injection and abstraction

    interface RuleInterface {
        public function matches($int);
    }

    class StepAccessControl
    {
       protected $rules;

       public function __construct(array $rules)
       {
           foreach($rules as $key => $rule) {
               $this->addRule($key, $rule);
           }
       }

       public isAccessGranted($actualOrderStep)
       {
           $isAccessGranted = TRUE;

           foreach($this->rules as $rule) {
               if (!$rule->matches($actualOrderStep) {
                   $isAccessGranted = FALSE;
               }
           }

           return $isAccessGranted;
       }

       public function addRule($key, RuleInterface $rule)
       {
           $this->rules[$key] = $rule;
       }
    }

    class OrderStepTwoRule implements RuleInterface
    {
        public function matches($actualStep)
        {
            $matches = TRUE;

            if (!($actualStep >= 1)) {
                $isStepAccessAuthorized = FALSE;
            }

            return $matches;
        }
    }

    class StepAccessControlFactory
    {
        public function build($stepNumber)
        {
            if ($stepNumber == 1) {
                ...
            } elseif ($stepNumber == 2) {
                $orderStepTwoRule = new OrderStepTwoRule();
                return new StepAcessControl($orderStepTwoRule);
            }...
        }
    }

and then in the controller :

    public function stepTwoAction()
    {
        $stepAccessControlFactory = new StepAccessControlFactory();
        $stepTwoAccessControl = $stepAccessControlFactory(2);

        if (!$stepTwoAccessControl->isAccesGranted($_SESSION['actualOrderStep'])) {
            return FALSE;
        }
    }

I would like to know if I get the spirit and if I am on the good way :)