Merge pull request #11 from P4BGroup/feat/fixes

hotfix/rebuild-tree

Author: Flaviu Chelaru

src/Behavior.php

@@ -222,8 +222,10 @@ public function processUpdate(ModelInterface $model): void
 
         $right = $parentModel->readAttribute(self::$rightKey);
         $depth = $parentModel->readAttribute(self::$depthKey);
-        if (
-            $parentModel->readAttribute(self::$rightKey) > $currentModel->readAttribute(self::$rightKey)
+        if ($currentModel->readAttribute(self::$rightKey) == 0) {
+            $right = $parentModel->readAttribute(self::$rightKey);
+            $depth = $parentModel->readAttribute(self::$depthKey) + 1;
+        } elseif ($parentModel->readAttribute(self::$rightKey) > $currentModel->readAttribute(self::$rightKey)
             && $parentModel->readAttribute(self::$rightKey) > $currentModel->readAttribute(self::$leftKey)
         ) {
             $right = $parentModel->readAttribute(self::$rightKey) - 2;