Default to first active form if widget form id not present

[MAILPOET-3847]

lib/Form/FormsRepository.php

@@ -27,6 +27,22 @@ class FormsRepository extends Repository {
       ->getResult();
   }
 
+  /**
+   * @return FormEntity[]
+   */
+  public function findAllActive(): array {
+    return $this->entityManager
+      ->createQueryBuilder()
+      ->select('f')
+      ->from(FormEntity::class, 'f')
+      ->where('f.status = (:enabled)')
+      ->andWhere('f.deletedAt IS NULL')
+      ->setParameter('enabled', FormEntity::STATUS_ENABLED)
+      ->orderBy('f.name', 'asc')
+      ->getQuery()
+      ->getResult();
+  }
+
   public function getNamesOfFormsForSegments(): array {
     $allNonDeletedForms = $this->findAllNotDeleted();
 

lib/Form/Widget.php

@@ -197,8 +197,16 @@ class Widget extends \WP_Widget {
     );
 
     // get form
-    if (empty($instance['form'])) return '';
+    if (!empty($instance['form'])) {
       $form = $this->formsRepository->findOneById($instance['form']);
+    } else {
+      // Backwards compatibility for MAILPOET-3847
+      // Get first active form
+      $forms = $this->formsRepository->findAllActive();
+      if (empty($forms)) return '';
+      $form = $forms[0];
+    }
+
     if (!$form) return '';
     if ($form->getDeletedAt()) return '';
     if ($form->getStatus() !== FormEntity::STATUS_ENABLED) return '';