BNF: Library import forms. DDFHER-166

Allowing the editor to input either a UUID or URL to a content.
We will then display a preview, where they can see the title.
If they wish to continue, they can import, and the node will
be created, and they will be redirected to the edit form.

web/modules/custom/bnf/bnf.module

@@ -3,6 +3,7 @@
 use Drupal\bnf\BnfStateEnum;
 use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\node\NodeInterface;
 
 /**
  * Implements hook_entity_base_field_info().
@@ -41,3 +42,28 @@ function bnf_get_bnf_state_allowed_values(): array {
   }
   return $values;
 }
+
+/**
+ * Implements theme_preprocess_html().
+ *
+ * Adding the node UUID as a metatag, that we can use when the user submits
+ * a URL to the BNF import form.
+ */
+function bnf_preprocess_html(array &$variables): void {
+  $route = \Drupal::routeMatch();
+  $node = $route->getParameter('node');
+
+  if ($route->getRouteName() !== 'entity.node.canonical' || !($node instanceof NodeInterface)) {
+    return;
+  }
+
+  $uuid_metatag = [
+    '#tag' => 'meta',
+    '#attributes' => [
+      'name' => 'uuid',
+      'content' => $node->uuid(),
+    ],
+  ];
+
+  $variables['page']['#attached']['html_head'][] = [$uuid_metatag, 'node-uuid'];
+}

web/modules/custom/bnf/bnf_client/bnf_client.links.menu.yml

@@ -0,0 +1,6 @@
+---
+bnf_client.import_content:
+  title: 'Import BNF content'
+  parent: system.admin_content
+  route_name: bnf_client.import_form
+  weight: 10

web/modules/custom/bnf/bnf_client/bnf_client.permissions.yml

@@ -1,2 +1,4 @@
 bnf client export nodes:
   title: 'Can export nodes to BNF'
+bnf client import nodes:
+  title: 'Can import nodes from BNF'

web/modules/custom/bnf/bnf_client/bnf_client.routing.yml

@@ -0,0 +1,16 @@
+---
+bnf_client.import_form:
+  path: '/admin/bnf/import'
+  defaults:
+    _form: '\Drupal\bnf_client\Form\BnfImportForm'
+    _title: 'Import'
+  requirements:
+    _permission: 'bnf client import nodes'
+
+bnf_client.import_confirm_form:
+  path: '/admin/bnf/import/{uuid}'
+  defaults:
+    _form: '\Drupal\bnf_client\Form\BnfImportConfirmForm'
+    _title: 'Confirm import'
+  requirements:
+    _permission: 'bnf client import nodes'

web/modules/custom/bnf/bnf_client/src/Form/BnfImportConfirmForm.php

@@ -0,0 +1,100 @@
+<?php
+
+namespace Drupal\bnf_client\Form;
+
+use Drupal\bnf\Services\BnfImporter;
+use Drupal\Core\DependencyInjection\AutowireTrait;
+use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
+use Drupal\Core\Form\FormInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Displaying an import preview, and allowing editor to import.
+ */
+class BnfImportConfirmForm implements FormInterface, ContainerInjectionInterface {
+  use StringTranslationTrait;
+
+  use AutowireTrait;
+
+  /**
+   * {@inheritDoc}
+   */
+  public function __construct(
+    protected RouteMatchInterface $routeMatch,
+    protected BnfImporter $bnfImporter,
+  ) {}
+
+  /**
+   * {@inheritDoc}
+   */
+  public static function create(ContainerInterface $container): static {
+    return new static(
+      $container->get('current_route_match'),
+      $container->get('bnf.importer')
+    );
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function getFormId(): string {
+    return 'bnf_import_form_form';
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state): array {
+    $form['#title'] = $this->t('Confirm import of BNF content', [], ['context' => 'BNF']);
+
+    $uuid = $this->routeMatch->getParameter('uuid');
+    $bnfServer = (string) getenv('BNF_SERVER_GRAPHQL_ENDPOINT');
+
+    $form_state->set('uuid', $uuid);
+    $form_state->set('bnfServer', $bnfServer);
+
+    $nodeData = $this->bnfImporter->loadNodeData($uuid, $bnfServer);
+
+    $form['uuid'] = [
+      '#title' => 'UUID',
+      '#type' => 'textfield',
+      '#default_value' => $uuid,
+      '#disabled' => TRUE,
+    ];
+
+    $form['label'] = [
+      '#title' => $this->t('Content label', [], ['context' => 'BNF']),
+      '#type' => 'textfield',
+      '#default_value' => $nodeData['title'] ?? NULL,
+      '#disabled' => TRUE,
+    ];
+
+    $form['actions']['submit'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Import content'),
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state): void {
+
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state): void {
+    $uuid = $form_state->get('uuid');
+    $bnfServer = $form_state->get('bnfServer');
+    $node = $this->bnfImporter->importNode($uuid, $bnfServer);
+    $form_state->setRedirect('entity.node.edit_form', ['node' => $node->id()]);
+  }
+
+}

web/modules/custom/bnf/bnf_client/src/Form/BnfImportForm.php

@@ -0,0 +1,94 @@
+<?php
+
+namespace Drupal\bnf_client\Form;
+
+use Drupal\Component\Uuid\Uuid;
+use Drupal\Core\DependencyInjection\AutowireTrait;
+use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
+use Drupal\Core\Form\FormInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+use function Safe\get_meta_tags;
+
+/**
+ * An import form, letting editors input URL or UUID from BNF.
+ */
+class BnfImportForm implements FormInterface, ContainerInjectionInterface {
+  use StringTranslationTrait;
+
+  use AutowireTrait;
+
+  /**
+   * {@inheritDoc}
+   */
+  public function getFormId(): string {
+    return 'bnf_initial_form';
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state): array {
+    $form['#title'] = $this->t('Import nodes from BNF', [], ['context' => 'BNF']);
+    $form['reference'] = [
+      '#type' => 'textfield',
+      '#title' => $this->t('URL or UUID of content'),
+    ];
+
+    $form['actions'] = [
+      '#type' => 'actions',
+    ];
+
+    $form['actions']['submit'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Preview content'),
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state): void {
+    $reference = $form_state->getValue('reference');
+    $uuid = $this->parseAndValidateUuid($reference);
+
+    if (empty($uuid)) {
+      $form_state->setErrorByName(
+        'reference',
+        $this->t('Invalid URL or UUID.', [], ['context' => 'BNF'])
+      );
+    }
+
+    $form_state->set('uuid', $uuid);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state): void {
+    $uuid = $form_state->get('uuid');
+    $form_state->setRedirect('bnf_client.import_confirm_form', ['uuid' => $uuid]);
+  }
+
+  /**
+   * Getting and validate a UUID from string or URL.
+   */
+  protected function parseAndValidateUuid(string $reference): string|false {
+    try {
+      // Detect if reference is a URL.
+      if (filter_var($reference, FILTER_VALIDATE_URL)) {
+        // Finding the metatag that contains the UUID.
+        $meta_tags = get_meta_tags($reference);
+        $reference = $meta_tags['uuid'] ?? NULL;
+      }
+
+      return Uuid::isValid((string) $reference) ? $reference : FALSE;
+    }
+    catch (\Exception) {
+      return FALSE;
+    }
+  }
+
+}