handle slugs in persistent data manager

src/PersistentData/PersistentDataManager.php

@@ -8,6 +8,7 @@ use SokoWeb\Interfaces\Database\IAuditLogger;
 use SokoWeb\Interfaces\Database\IResultSet;
 use SokoWeb\Interfaces\PersistentData\IPersistentDataManager;
 use SokoWeb\PersistentData\Model\Model;
+use SokoWeb\PersistentData\Model\ModelWithSlug;
 
 class PersistentDataManager implements IPersistentDataManager
 {
@@ -58,6 +59,14 @@ class PersistentDataManager implements IPersistentDataManager
         return $this->selectFromDb($select, $type, $useRelations, $withRelations);
     }
 
+    public function selectFromDbBySlug(string $slug, string $type, bool $useRelations = false, array $withRelations = [])
+    {
+        $select = new Select($this->dbConnection);
+        $select->where('slug', '=', $slug);
+
+        return $this->selectFromDb($select, $type, $useRelations, $withRelations);
+    }
+
     public function loadRelationsFromDb(Model $model, bool $recursive = false, array $withRelations = []): void
     {
         $relations = $model::getRelations();
@@ -103,12 +112,20 @@ class PersistentDataManager implements IPersistentDataManager
             }
 
             if (count($modified) > 0) {
+                if ($model instanceof ModelWithSlug && isset($modified['slug'])) {
+                    $modified['slug'] = $this->generateUniqueSlug($model, $modified['slug']);
+                }
+
                 $modify->setId($id);
                 $modify->setDiff($diff);
                 $modify->fill($modified);
                 $modify->save();
             }
         } else {
+            if ($model instanceof ModelWithSlug) {
+                $modified['slug'] = $this->generateUniqueSlug($model, $modified['slug']);
+            }
+
             $modify->fill($modified);
             $modify->save();
 
@@ -129,6 +146,27 @@ class PersistentDataManager implements IPersistentDataManager
         $model->resetSnapshot();
     }
 
+    private function generateUniqueSlug(ModelWithSlug $model, string $notUniqueSlug): string
+    {
+        $slug = $notUniqueSlug;
+        $numbered = 0;
+
+        do {
+            if ($numbered > 0) {
+                $slug = $slug . '_' . ($numbered + 1);
+            }
+
+            $select = new Select($this->dbConnection, $model::getTable());
+            $select->where('slug', '=', $slug);
+
+            $numbered++;
+        } while ($select->count() != 0);
+
+        $model->setSlug($slug);
+
+        return $slug;
+    }
+
     private function createSelect(Select $select, string $type, bool $useRelations = false, array $withRelations = []): Select
     {
         $table = call_user_func([$type, 'getTable']);