schedule explicit set levels

backend/app/Set/UseCases/GetSetLayout/GetSetLayout.php

@@ -6,11 +6,13 @@ use App\Element\Element;
 use App\Element\ElementRepository;
 use App\Exceptions\NotFoundException;
 use App\Set\SetRepository;
+use App\Set\SetLevelRepository;
 
 class GetSetLayout
 {
     public function __construct(
         private SetRepository $setRepository,
+        private SetLevelRepository $setLevelRepository,
         private ElementRepository $elementRepository,
     ) {}
 
@@ -24,10 +26,15 @@ class GetSetLayout
             throw new NotFoundException('set not found');
         }
 
+        $elements = $this->elementRepository->findBySet($set);
         $elementsByParentId = [];
-        foreach ($this->elementRepository->findBySet($set) as $element) {
+        $elementCountsByLevelId = [];
+        foreach ($elements as $element) {
             $parentId = $element->getParentElement()?->getId() ?? 0;
             $elementsByParentId[$parentId][] = $element;
+            $levelId = $element->getLevel()->getId();
+            $elementCountsByLevelId[$levelId]
+                = ($elementCountsByLevelId[$levelId] ?? 0) + 1;
         }
 
         foreach ($elementsByParentId as &$siblings) {
@@ -46,8 +53,17 @@ class GetSetLayout
         }
         unset($siblings);
 
+        $layoutLevels = [];
+        foreach ($this->setLevelRepository->findBySet($set) as $level) {
+            $layoutLevels[] = new SetLayoutLevel(
+                level: $level,
+                elementCount: $elementCountsByLevelId[$level->getId()] ?? 0,
+            );
+        }
+
         return new SetLayout(
             set: $set,
+            levels: $layoutLevels,
             elements: $this->buildNodes(0, $elementsByParentId),
         );
     }