Update BnfImporter to import text and accordion paragraphs.

Making some assumptions on how graphql_compose builds the links
(as there is no way of doing it reverse, as far as I can see..),
we build a query that looks up available fields, on paragraphs
we support.

This feels a bit dirty, but for now, until we've cleared how to
deal with GraphQL schemas/codegen, it'll do.
Only text_body and accordion paragraphs are imported.

web/modules/custom/bnf/src/Services/BnfImporter.php

@@ -4,12 +4,17 @@
 
 use Drupal\bnf\BnfStateEnum;
 use Drupal\bnf\Exception\AlreadyExistsException;
+use Drupal\Core\Entity\EntityFieldManagerInterface;
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\StringTranslation\TranslationInterface;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\paragraphs\ParagraphInterface;
 use GuzzleHttp\ClientInterface;
 use Psr\Log\LoggerInterface;
 use function Safe\json_decode;
 use function Safe\parse_url;
+use function Safe\preg_replace;
 
 /**
  * Service related to importing content from an external source.
@@ -20,20 +25,224 @@
  */
 class BnfImporter {
 
+  const ALLOWED_PARAGRAPHS = [
+    'ParagraphTextBody' => 'text_body',
+    'ParagraphAccordion' => 'accordion',
+  ];
+
+  /**
+   * The BNF UUID of the content that we import.
+   */
+  protected string $uuid;
+
   /**
    * Constructor.
    */
   public function __construct(
     protected ClientInterface $httpClient,
+    protected EntityFieldManagerInterface $entityFieldManager,
     protected EntityTypeManagerInterface $entityTypeManager,
     protected TranslationInterface $translation,
     protected LoggerInterface $logger,
   ) {}
 
+  /**
+   * Loading the columns of a field, that we use to ask GraphQL for data.
+   *
+   * E.g. a WYSIWYG field will have both a "value" and a "format" that we want
+   * to pull out.
+   *
+   * @return mixed[]
+   *   Return an array of fields, along with their column keys.
+   */
+  protected function getFieldColumns(string $entityType, string $bundle): array {
+    $values = [];
+    $fields = [];
+    $fieldDefinitions = $this->entityFieldManager->getFieldDefinitions($entityType, $bundle);
+
+    foreach ($fieldDefinitions as $fieldKey => $fieldDefinition) {
+      if ($fieldDefinition instanceof FieldConfig) {
+        $fields[] = $fieldKey;
+      }
+    }
+
+    foreach ($fields as $fieldKey) {
+      $field = $this->entityTypeManager->getStorage('field_storage_config')->load("$entityType.$fieldKey");
+
+      if ($field instanceof FieldStorageConfig) {
+        $values[$fieldKey] = array_keys($field->getColumns());
+      }
+    }
+
+    return $values;
+  }
+
+  /**
+   * Builds the query used to get data from the source.
+   */
+  public function getQuery(string $queryName): string {
+    // Start building the GraphQL query.
+    $query = <<<GRAPHQL
+    query {
+      $queryName(id: "$this->uuid") {
+        title
+        paragraphs {
+
+    GRAPHQL;
+
+    // Loop through allowed paragraphs and add their structures.
+    foreach (self::ALLOWED_PARAGRAPHS as $graphBundle => $drupalBundle) {
+      $query .= <<<GRAPHQL
+          ... on $graphBundle {
+            __typename
+
+        GRAPHQL;
+
+      // Add field columns for the current paragraph type.
+      $fieldColumns = $this->getFieldColumns('paragraph', $drupalBundle);
+      foreach ($fieldColumns as $fieldKey => $columns) {
+        $fieldKey = $this->drupalFieldToGraphField($fieldKey);
+
+        $columnsString = implode("\r\n ", $columns);
+        $query .= <<<GRAPHQL
+            $fieldKey {
+              $columnsString
+            }
+
+            GRAPHQL;
+      }
+
+      // Close the paragraph type block.
+      $query .= <<<GRAPHQL
+          }
+
+        GRAPHQL;
+    }
+
+    // Close the paragraphs and main query block.
+    $query .= <<<GRAPHQL
+        }
+      }
+    }
+    GRAPHQL;
+
+    return $query;
+  }
+
+  /**
+   * Turn GraphQL field format (camelCase) to Drupal format (snake_case).
+   */
+  protected function graphFieldToDrupalField(string $fieldKey): string {
+    // Prefix all capitalized letters with an underscore.
+    $fieldKey = preg_replace('/(?<!^)[A-Z]/', '_$0', $fieldKey);
+
+    // Lowercase everything.
+    $fieldKey = strtolower($fieldKey);
+
+    // Prefix with "field_".
+    return "field_$fieldKey";
+  }
+
+  /**
+   * Turn Drupal format (snake_case) to GraphQL field format (camelCase).
+   */
+  protected function drupalFieldToGraphField(string $fieldKey): string {
+    // Remove 'field_' prefix, if it exists.
+    if (str_starts_with($fieldKey, 'field_')) {
+      $fieldKey = substr($fieldKey, strlen('field_'));
+    }
+
+    // Replace underscores with spaces.
+    $fieldKey = str_replace('_', ' ', $fieldKey);
+
+    // Convert the first character of each word to uppercase.
+    $fieldKey = ucwords($fieldKey);
+
+    // Remove all spaces.
+    $fieldKey = str_replace(' ', '', $fieldKey);
+
+    // Make first letter lowercase, to match camelCase.
+    return lcfirst($fieldKey);
+  }
+
+  /**
+   * Parses paragraphs from GraphQL node data into Drupal-compatible structures.
+   *
+   * @param mixed[] $nodeData
+   *   The GraphQL node data containing paragraphs.
+   *
+   * @return mixed[]
+   *   Array of paragraph values, that we can use to create paragraph entities.
+   */
+  protected function parseGraphParagraphs(array $nodeData) {
+    $parsedParagraphs = [];
+
+    // Ensure paragraphs exist in the GraphQL response.
+    if (empty($nodeData['paragraphs'])) {
+      return $parsedParagraphs;
+    }
+
+    foreach ($nodeData['paragraphs'] as $paragraphData) {
+      $type = $paragraphData['__typename'] ?? '';
+
+      // Convert typename to Drupal paragraph bundle name.
+      $bundleName = self::ALLOWED_PARAGRAPHS[$type] ?? NULL;
+
+      if (empty($bundleName)) {
+        continue;
+      }
+
+      $paragraph = ['type' => $bundleName];
+
+      // Map fields dynamically.
+      foreach ($paragraphData as $key => $value) {
+        if ($key === '__typename') {
+          continue;
+        }
+
+        // Assume Drupal uses field names like "field_{key}".
+        $drupalFieldName = $this->graphFieldToDrupalField($key);
+        $paragraph[$drupalFieldName] = $value;
+      }
+
+      $parsedParagraphs[] = $paragraph;
+    }
+
+    return $parsedParagraphs;
+  }
+
+  /**
+   * Creating the paragraphs, that we will add to the nodes.
+   *
+   * @param mixed[] $nodeData
+   *   The GraphQL node data containing paragraphs.
+   *
+   * @return \Drupal\paragraphs\ParagraphInterface[]
+   *   The paragraph entities.
+   */
+  protected function getParagraphs(array $nodeData): array {
+    $parsedParagraphs = $this->parseGraphParagraphs($nodeData);
+    $storage = $this->entityTypeManager->getStorage('paragraph');
+    $paragraphs = [];
+    foreach ($parsedParagraphs as $paragraphData) {
+      $paragraph = $storage->create($paragraphData);
+
+      if ($paragraph instanceof ParagraphInterface) {
+        $paragraph->save();
+        $paragraphs[] = $paragraph;
+      }
+    }
+
+    return $paragraphs;
+  }
+
   /**
    * Importing a node from a GraphQL source endpoint.
    */
   public function importNode(string $uuid, string $endpointUrl, string $nodeType = 'article'): void {
+    $this->uuid = $uuid;
+    $queryName = 'node' . ucfirst($nodeType);
+
     $nodeStorage = $this->entityTypeManager->getStorage('node');
 
     $existingNodes =
@@ -48,18 +257,6 @@ public function importNode(string $uuid, string $endpointUrl, string $nodeType =
       throw new AlreadyExistsException('Cannot import node - already exists.');
     }
 
-    // Example of GraphQL query: "nodeArticle".
-    $queryName = 'node' . ucfirst($nodeType);
-
-    // For now, we only support the title of the nodes.
-    $query = <<<GRAPHQL
-    query {
-      $queryName(id: "$uuid") {
-        title
-      }
-    }
-    GRAPHQL;
-
     if (!filter_var($endpointUrl, FILTER_VALIDATE_URL)) {
       throw new \InvalidArgumentException('The provided callback URL is not valid.');
     }
@@ -71,6 +268,8 @@ public function importNode(string $uuid, string $endpointUrl, string $nodeType =
       throw new \InvalidArgumentException('The provided callback URL must use HTTPS.');
     }
 
+    $query = $this->getQuery($queryName);
+
     $response = $this->httpClient->request('post', $endpointUrl, [
       'headers' => [
         'Content-Type' => 'application/json',
@@ -87,14 +286,18 @@ public function importNode(string $uuid, string $endpointUrl, string $nodeType =
     $nodeData = $data['data'][$queryName] ?? NULL;
 
     if (empty($nodeData)) {
-      $this->logger->error('Could not find any node data in GraphQL response.');
+      $this->logger->error(
+        'Could not find any node data in GraphQL response. @query',
+        ['@query' => $queryName]
+      );
 
       throw new \Exception('Could not retrieve content values.');
     }
 
     try {
       $nodeData['type'] = $nodeType;
       $nodeData['uuid'] = $uuid;
+      $nodeData['field_paragraphs'] = $this->getParagraphs($nodeData);
 
       $node = $nodeStorage->create($nodeData);
       $node->save();