Convert WorkflowStepValidator to node-visitor-based rules

[MAILPOET-4659]

mailpoet/lib/Automation/Engine/Validation/WorkflowRules/ValidStepArgsRule.php

@@ -0,0 +1,44 @@
+<?php declare(strict_types = 1);
+
+namespace MailPoet\Automation\Engine\Validation\WorkflowRules;
+
+use MailPoet\Automation\Engine\Data\Workflow;
+use MailPoet\Automation\Engine\Registry;
+use MailPoet\Automation\Engine\Validation\WorkflowGraph\WorkflowNode;
+use MailPoet\Automation\Engine\Validation\WorkflowGraph\WorkflowNodeVisitor;
+use MailPoet\Validator\Validator;
+
+class ValidStepArgsRule implements WorkflowNodeVisitor {
+  /** @var Registry */
+  private $registry;
+
+  /** @var Validator */
+  private $validator;
+
+  public function __construct(
+    Registry $registry,
+    Validator $validator
+  ) {
+    $this->registry = $registry;
+    $this->validator = $validator;
+  }
+
+  public function initialize(Workflow $workflow): void {
+  }
+
+  public function visitNode(Workflow $workflow, WorkflowNode $node): void {
+    $step = $node->getStep();
+    $registryStep = $this->registry->getStep($step->getKey());
+    if (!$registryStep) {
+      return;
+    }
+
+    // validate args schema only for active workflows
+    if ($workflow->getStatus() !== Workflow::STATUS_ACTIVE) {
+      $this->validator->validate($registryStep->getArgsSchema(), $step->getArgs());
+    }
+  }
+
+  public function complete(Workflow $workflow): void {
+  }
+}