Issue #3173862: checking for duplicate ids on blocks only, still have to work on sections

layout_builder_ids.services.yml

@@ -9,6 +9,7 @@ services:
       - { name: 'event_subscriber' }
   layout_builder_ids.configure_block_form:
     class: '\Drupal\layout_builder_ids\EventSubscriber\LayoutBuilderIdsConfigureBlock'
+    arguments: ['@entity_type.manager', '@current_route_match']
     tags:
       - { name: 'event_subscriber' }
   layout_builder_ids.route_subscriber:

src/EventSubscriber/LayoutBuilderIdsConfigureBlock.php

@@ -2,7 +2,9 @@
 
 namespace Drupal\layout_builder_ids\EventSubscriber;
 
+use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Routing\RouteMatchInterface;
 use Drupal\core_event_dispatcher\Event\Form\FormAlterEvent;
 use Drupal\hook_event_dispatcher\HookEventDispatcherInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
@@ -13,6 +15,33 @@ use Drupal\Component\Utility\Html;
  */
 class LayoutBuilderIdsConfigureBlock implements EventSubscriberInterface {
 
+  /**
+   * Entity type manager from core.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * The variable for route match.
+   *
+   * @var \Drupal\Core\Routing\RouteMatchInterface
+   */
+  protected $routeMatch;
+
+  /**
+   * Constructor for event subscriber for configure block.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entityTypeManager
+   *   Entity type manager service.
+   * @param \Drupal\Core\Routing\RouteMatchInterface $routeMatch
+   *   Route match service.
+   */
+  public function __construct(EntityTypeManagerInterface $entityTypeManager, RouteMatchInterface $routeMatch) {
+    $this->entityTypeManager = $entityTypeManager;
+    $this->routeMatch = $routeMatch;
+  }
+
   /**
    * Alter form.
    *
@@ -45,11 +74,93 @@ class LayoutBuilderIdsConfigureBlock implements EventSubscriberInterface {
         '#description' => t('Block ID is an optional setting which is used to support an anchor link to this block. For example, entering "feature" lets you link directly to this block by adding "#feature" to the end of the URL.</br>IDs should start with a letter, may only contain letters, numbers, underscores, hyphens, and periods, and should be unique on the page.'),
       ];
 
+      $form['#validate'][] = [$this, 'layoutBuilderIdsFormValidation'];
+
       // Add our custom submit function.
       array_unshift($form['#submit'], [$this, 'layoutBuilderIdsSubmitForm']);
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function layoutBuilderIdsFormValidation(array &$form, FormStateInterface $form_state) {
+
+    // Get the layout builder id from the form state.
+    $layout_builder_id = $form_state->getValue(['settings', 'layout_builder_id']);
+
+    // If there is a block id specified, check that there are
+    // no duplicate ids.
+    if ($layout_builder_id !== '') {
+
+      // Get the current node from the route match, it is in
+      // the form node.<nid>.
+      $nid = $this->routeMatch->getRawParameters()->get('section_storage');
+
+      // If there is an nid, load the node.
+      if (isset($nid)) {
+
+        // Get the nid which is currently in the format node.<nid>.
+        $nid = (integer) str_replace('node.', '', $nid);
+
+        // Load the node.
+        $node = $this->entityTypeManager->getStorage('node')->load($nid);
+      }
+
+      // Get the layout from the node.
+      $layout = $node->layout_builder__layout;
+
+      // A boolean variable to check if we have found a duplicate id.
+      $found_id = FALSE;
+
+      // Step through each section and check for a duplicate.
+      foreach ($layout as $section) {
+
+        // Get the components of each section.
+        $components = $section->section->getComponents();
+
+        // Step through each of the components.
+        foreach ($components as $component) {
+
+          // Get the additional settings from the component.
+          $additional = $component->get('additional');
+
+          // If the additional settings are set, check if
+          // specified id is a duplicate.
+          if (isset($additional['layout_builder_id'])) {
+
+            // If there is already an id with the one specified,
+            // set the flag.
+            if ($additional['layout_builder_id'] == $layout_builder_id) {
+
+              // Set the flag that we have found a duplicate id.
+              $found_id = TRUE;
+
+              // Break from the loop to save computational time.
+              break;
+            }
+          }
+
+          // If we have already found a duplicate id, break from
+          // the outer loop to save computational time.
+          if ($found_id) {
+            break;
+          }
+        }
+      }
+    }
+
+    // @todo Have to look through all the sections and check
+    // for duplicate ids as well.  This only does blocks.
+    // If we have found a duplicate id, set the form error.
+    if ($found_id) {
+
+      // Set the form error on the block ID element.
+      $form_state->setError($form['settings']['layout_builder_id'], 'There is already a block or section with the ID "' . $layout_builder_id . '".');
+    }
+
+  }
+
   /**
    * {@inheritdoc}
    */