Allow to create nested entitiy structures directly from the part edit page.

However there is still a bug, that the newly created entites are not shown as selected (even though they are). Fixes issue #203

src/Form/Type/Helper/StructuralEntityChoiceLoader.php

@@ -22,6 +22,7 @@ namespace App\Form\Type\Helper;
 
 use App\Entity\Base\AbstractDBElement;
 use App\Entity\Base\AbstractStructuralDBElement;
+use App\Repository\StructuralDBElementRepository;
 use App\Services\Trees\NodesListBuilder;
 use Doctrine\ORM\EntityManagerInterface;
 use Symfony\Component\Form\ChoiceList\Loader\AbstractChoiceLoader;
@@ -33,6 +34,8 @@ class StructuralEntityChoiceLoader extends AbstractChoiceLoader
     private NodesListBuilder $builder;
     private EntityManagerInterface $entityManager;
 
+    private ?string $additional_element = null;
+
     public function __construct(Options $options, NodesListBuilder $builder, EntityManagerInterface $entityManager)
     {
         $this->options = $options;
@@ -42,10 +45,16 @@ class StructuralEntityChoiceLoader extends AbstractChoiceLoader
 
     protected function loadChoices(): iterable
     {
-        return $this->builder->typeToNodesList($this->options['class'], null);
+        $tmp = [];
+        if ($this->additional_element) {
+            $tmp = $this->createNewEntitiesFromValue($this->additional_element);
+            $this->additional_element = null;
         }
 
-    public function loadChoicesForValues(array $values, callable $value = null)
+        return array_merge($tmp, $this->builder->typeToNodesList($this->options['class'], null));
+    }
+
+    /*public function loadChoicesForValues(array $values, callable $value = null)
     {
         $tmp = parent::loadChoicesForValues($values, $value);
 
@@ -59,29 +68,13 @@ class StructuralEntityChoiceLoader extends AbstractChoiceLoader
                 return $tmp;
             }
 
-            return [$this->createNewEntityFromValue((string)$values[0])];
+            return [$this->createNewEntitiesFromValue($values[0])[0]];
-        }
-
-        return $tmp;
-    }
-
-    /*public function loadValuesForChoices(array $choices, callable $value = null)
-    {
-        $tmp = parent::loadValuesForChoices($choices, $value);
-
-        if ($this->options['allow_add'] && count($tmp) === 1) {
-            if ($tmp[0] instanceof AbstractDBElement && $tmp[0]->getID() === null) {
-                return [$tmp[0]->getName()];
-            }
-
-            return [(string)$choices[0]->getID()];
         }
 
         return $tmp;
     }*/
 
-
+    public function createNewEntitiesFromValue(string $value): array
-    public function createNewEntityFromValue(string $value): AbstractStructuralDBElement
     {
         if (!$this->options['allow_add']) {
             throw new \RuntimeException('Cannot create new entity, because allow_add is not enabled!');
@@ -92,13 +85,32 @@ class StructuralEntityChoiceLoader extends AbstractChoiceLoader
         }
 
         $class = $this->options['class'];
-        /** @var AbstractStructuralDBElement $entity */
+        /** @var StructuralDBElementRepository $repo */
-        $entity = new $class();
+        $repo = $this->entityManager->getRepository($class);
-        $entity->setName($value);
 
-        //Persist element to database
+        $entities = $repo->getNewEntityFromPath($value, '->');
+
+        $results = [];
+
+        foreach($entities as $entity) {
+            //If the entity is newly created (ID null), add it as result and persist it.
+            if ($entity->getID() === null) {
                 $this->entityManager->persist($entity);
+                $results[] = $entity;
+            }
+        }
 
-        return $entity;
+        return $results;
     }
+
+    public function setAdditionalElement(?string $element): void
+    {
+        $this->additional_element = $element;
+    }
+
+    public function getAdditionalElement(): ?string
+    {
+        return $this->additional_element;
+    }
+
 }

src/Form/Type/StructuralEntityType.php

@@ -31,9 +31,12 @@ use Doctrine\ORM\EntityManagerInterface;
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\CallbackTransformer;
 use Symfony\Component\Form\ChoiceList\Loader\CallbackChoiceLoader;
+use Symfony\Component\Form\Event\PostSubmitEvent;
+use Symfony\Component\Form\Event\PreSubmitEvent;
 use Symfony\Component\Form\Exception\TransformationFailedException;
 use Symfony\Component\Form\Extension\Core\Type\ChoiceType;
 use Symfony\Component\Form\FormBuilderInterface;
+use Symfony\Component\Form\FormEvents;
 use Symfony\Component\Form\FormInterface;
 use Symfony\Component\Form\FormView;
 use Symfony\Component\OptionsResolver\Options;
@@ -65,6 +68,38 @@ class StructuralEntityType extends AbstractType
 
     public function buildForm(FormBuilderInterface $builder, array $options): void
     {
+        $builder->addEventListener(FormEvents::PRE_SUBMIT, function (PreSubmitEvent $event) {
+            //When the data contains non-digit characters, we assume that the user entered a new element.
+            //In that case we add the new element to our choice_loader
+
+            $data = $event->getData();
+            if (null === $data || !is_string($data) || $data === "" || ctype_digit($data)) {
+                return;
+            }
+
+            $form = $event->getForm();
+            $options = $form->getConfig()->getOptions();
+            $choice_loader = $options['choice_loader'];
+            if ($choice_loader instanceof StructuralEntityChoiceLoader) {
+                $choice_loader->setAdditionalElement($data);
+            }
+        });
+
+       /* $builder->addEventListener(FormEvents::POST_SUBMIT, function (PostSubmitEvent $event) {
+           $name =  $event->getForm()->getConfig()->getName();
+           $data = $event->getForm()->getData();
+
+           if ($event->getForm()->getParent() === null) {
+               return;
+           }
+
+           $event->getForm()->getParent()->add($name, static::class, $event->getForm()->getConfig()->getOptions());
+           $new_form = $event->getForm()->getParent()->get($name);
+           $new_form->setData($data);
+        });*/
+
+
+
         $builder->addModelTransformer(new CallbackTransformer(
             function ($value) use ($options) {
                 return $this->modelTransform($value, $options);
@@ -81,7 +116,18 @@ class StructuralEntityType extends AbstractType
             'show_fullpath_in_subtext' => true, //When this is enabled, the full path will be shown in subtext
             'subentities_of' => null,   //Only show entities with the given parent class
             'disable_not_selectable' => false,  //Disable entries with not selectable property
-            'choice_value' => 'id', //Use the element id as option value and for comparing items
+            'choice_value' => function (?AbstractStructuralDBElement $element) {
+                if ($element === null) {
+                    return null;
+                }
+
+                if ($element->getID() === null) {
+                    //Must be the same as the separator in the choice_loader, otherwise this will not work!
+                    return $element->getFullPath('->');
+                }
+
+                return $element->getID();
+            }, //Use the element id as option value and for comparing items
             'choice_loader' => function (Options $options) {
                 return new StructuralEntityChoiceLoader($options, $this->builder, $this->em);
             },
@@ -95,6 +141,15 @@ class StructuralEntityType extends AbstractType
                     return $this->generateChoiceAttr($choice, $key, $value, $options);
                 };
             },
+            'group_by' => function (AbstractStructuralDBElement $element)
+            {
+                //Show entities that are not added to DB yet separately from other entities
+                if ($element->getID() === null) {
+                    return 'New (not added to DB yet)';
+                }
+
+                return null;
+            },
             'choice_translation_domain' => false, //Don't translate the entity names
         ]);
 

src/Repository/StructuralDBElementRepository.php

@@ -89,4 +89,38 @@ class StructuralDBElementRepository extends NamedDBElementRepository
 
         return $result;
     }
+
+    /**
+     * Creates a structure of AbsstractStructuralDBElements from a path separated by $separator, which splits the various levels.
+     * This function will try to use existing elements, if they are already in the database. If not, they will be created.
+     * An array of the created elements will be returned, with the last element being the deepest element.
+     * @param  string  $path
+     * @param  string  $separator
+     * @return AbstractStructuralDBElement[]
+     */
+    public function getNewEntityFromPath(string $path, string $separator = '->'): array
+    {
+        $parent = null;
+        $result = [];
+        foreach (explode($separator, $path) as $name) {
+            $name = trim($name);
+            if ('' === $name) {
+                continue;
+            }
+
+            //See if we already have an element with this name and parent
+            $entity = $this->findOneBy(['name' => $name, 'parent' => $parent]);
+            if (null === $entity) {
+                /** @var AbstractStructuralDBElement $entity */
+                $entity = new ($this->getClassName());
+                $entity->setName($name);
+                $entity->setParent($parent);
+            }
+
+            $result[] = $entity;
+            $parent = $entity;
+        }
+
+        return $result;
+    }
 }