Feat: Avoid adding of existing availabilities

src/Entity/Availability.php

@@ -10,9 +10,15 @@ use Doctrine\Common\Collections\ArrayCollection;
 use Doctrine\Common\Collections\Collection;
 use Doctrine\DBAL\Types\Types;
 use Doctrine\ORM\Mapping as ORM;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Validator\Constraints as Assert;
 
 #[ORM\Entity(repositoryClass: AvailabilityRepository::class)]
+#[UniqueEntity(
+    fields: ['dateFrom', 'dateTo'],
+    message: 'Eine Verfügbarkeit für diesen Zeitraum ist bereits vorhanden',
+    repositoryMethod: 'assertUnique'
+)]
 class Availability implements BlameableEntityInterface, TimestampableEntityInterface, SoftDeletableEntityInterface
 {
     use BlameableEntity;

src/Repository/AvailabilityRepository.php

@@ -78,4 +78,20 @@ class AvailabilityRepository extends ServiceEntityRepository
             ->getResult()
         ;
     }
+
+    public function assertUnique(array $fields): array
+    {
+        $qb = $this->createQueryBuilder('availability');
+
+        return $qb
+            ->where($qb->expr()->andX(
+                $qb->expr()->eq('availability.dateFrom', ':dateFrom'),
+                $qb->expr()->eq('availability.dateTo', ':dateTo'),
+                $qb->expr()->isNull('availability.owner')
+            ))
+            ->setParameters($fields)
+            ->getQuery()
+            ->getResult()
+        ;
+    }
 }