feat: implement polymorphic relationships for group items to support bundles and product variants

app/Domains/Catalog/Models/GroupItem.php

@@ -4,6 +4,7 @@ namespace App\Domains\Catalog\Models;
 
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\MorphTo;
 
 class GroupItem extends Model
 {
@@ -11,7 +12,8 @@ class GroupItem extends Model
 
     protected $fillable = [
         'featured_group_id',
-        'product_variant_id',
+        'groupable_type',
+        'groupable_id',
         'order',
     ];
 
@@ -20,8 +22,8 @@ class GroupItem extends Model
         return $this->belongsTo(FeaturedGroup::class);
     }
 
-    public function variant(): BelongsTo
+    public function groupable(): MorphTo
     {
-        return $this->belongsTo(ProductVariant::class, 'product_variant_id');
+        return $this->morphTo();
     }
 }

app/Domains/Catalog/Models/ProductVariant.php

@@ -12,6 +12,7 @@ use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\Relations\BelongsToMany;
 use Illuminate\Database\Eloquent\Relations\HasMany;
+use Illuminate\Database\Eloquent\Relations\MorphMany;
 
 #[Fillable([
     'producto_id',
@@ -217,4 +218,12 @@ class ProductVariant extends Model implements Buyable
             'attachment_id'
         )->withTimestamps();
     }
+
+    /**
+     * @return MorphMany<GroupItem, $this>
+     */
+    public function groupItems(): MorphMany
+    {
+        return $this->morphMany(GroupItem::class, 'groupable');
+    }
 }