add refresh token

lib/features/products/data/models/product_model.dart

@@ -31,10 +31,10 @@ class ProductModel extends HiveObject {
   final bool isAvailable;
 
   @HiveField(8)
-  final DateTime createdAt;
+  final DateTime? createdAt;
 
   @HiveField(9)
-  final DateTime updatedAt;
+  final DateTime? updatedAt;
 
   ProductModel({
     required this.id,
@@ -45,8 +45,8 @@ class ProductModel extends HiveObject {
     required this.categoryId,
     required this.stockQuantity,
     required this.isAvailable,
-    required this.createdAt,
-    required this.updatedAt,
+    this.createdAt,
+    this.updatedAt,
   });
 
   /// Convert to domain entity
@@ -92,8 +92,12 @@ class ProductModel extends HiveObject {
       categoryId: json['categoryId'] as String,
       stockQuantity: json['stockQuantity'] as int? ?? 0,
       isAvailable: json['isAvailable'] as bool? ?? true,
-      createdAt: DateTime.parse(json['createdAt'] as String),
-      updatedAt: DateTime.parse(json['updatedAt'] as String),
+      createdAt: json['createdAt'] != null
+          ? DateTime.parse(json['createdAt'] as String)
+          : null,
+      updatedAt: json['updatedAt'] != null
+          ? DateTime.parse(json['updatedAt'] as String)
+          : null,
     );
   }
 
@@ -108,8 +112,8 @@ class ProductModel extends HiveObject {
       'categoryId': categoryId,
       'stockQuantity': stockQuantity,
       'isAvailable': isAvailable,
-      'createdAt': createdAt.toIso8601String(),
-      'updatedAt': updatedAt.toIso8601String(),
+      'createdAt': createdAt?.toIso8601String(),
+      'updatedAt': updatedAt?.toIso8601String(),
     };
   }
 }

lib/features/products/data/models/product_model.g.dart

@@ -25,8 +25,8 @@ class ProductModelAdapter extends TypeAdapter<ProductModel> {
       categoryId: fields[5] as String,
       stockQuantity: (fields[6] as num).toInt(),
       isAvailable: fields[7] as bool,
-      createdAt: fields[8] as DateTime,
-      updatedAt: fields[9] as DateTime,
+      createdAt: fields[8] as DateTime?,
+      updatedAt: fields[9] as DateTime?,
     );
   }
 

lib/features/products/domain/entities/product.dart

@@ -10,8 +10,8 @@ class Product extends Equatable {
   final String categoryId;
   final int stockQuantity;
   final bool isAvailable;
-  final DateTime createdAt;
-  final DateTime updatedAt;
+  final DateTime? createdAt;
+  final DateTime? updatedAt;
 
   const Product({
     required this.id,
@@ -22,8 +22,8 @@ class Product extends Equatable {
     required this.categoryId,
     required this.stockQuantity,
     required this.isAvailable,
-    required this.createdAt,
-    required this.updatedAt,
+    this.createdAt,
+    this.updatedAt,
   });
 
   @override

lib/features/products/presentation/pages/product_detail_page.dart

@@ -296,14 +296,18 @@ class ProductDetailPage extends ConsumerWidget {
               context,
               icon: Icons.calendar_today,
               label: 'Created',
-              value: dateFormat.format(product.createdAt),
+              value: product.createdAt != null
+                  ? dateFormat.format(product.createdAt!)
+                  : 'N/A',
             ),
             const Divider(height: 24),
             _buildInfoRow(
               context,
               icon: Icons.update,
               label: 'Last Updated',
-              value: dateFormat.format(product.updatedAt),
+              value: product.updatedAt != null
+                  ? dateFormat.format(product.updatedAt!)
+                  : 'N/A',
             ),
           ],
         ),

lib/features/products/presentation/pages/products_page.dart

@@ -493,10 +493,18 @@ class _ProductsPageState extends ConsumerState<ProductsPage> {
         sorted.sort((a, b) => b.price.compareTo(a.price));
         break;
       case ProductSortOption.newest:
-        sorted.sort((a, b) => b.createdAt.compareTo(a.createdAt));
+        sorted.sort((a, b) {
+          final aDate = a.createdAt ?? DateTime(2000);
+          final bDate = b.createdAt ?? DateTime(2000);
+          return bDate.compareTo(aDate);
+        });
         break;
       case ProductSortOption.oldest:
-        sorted.sort((a, b) => a.createdAt.compareTo(b.createdAt));
+        sorted.sort((a, b) {
+          final aDate = a.createdAt ?? DateTime(2000);
+          final bDate = b.createdAt ?? DateTime(2000);
+          return aDate.compareTo(bDate);
+        });
         break;
     }
 

lib/features/products/presentation/providers/filtered_products_provider.dart

@@ -91,10 +91,18 @@ class SortedProducts extends _$SortedProducts {
         sorted.sort((a, b) => b.price.compareTo(a.price));
         break;
       case ProductSortOption.newest:
-        sorted.sort((a, b) => b.createdAt.compareTo(a.createdAt));
+        sorted.sort((a, b) {
+          final aDate = a.createdAt ?? DateTime(2000);
+          final bDate = b.createdAt ?? DateTime(2000);
+          return bDate.compareTo(aDate);
+        });
         break;
       case ProductSortOption.oldest:
-        sorted.sort((a, b) => a.createdAt.compareTo(b.createdAt));
+        sorted.sort((a, b) {
+          final aDate = a.createdAt ?? DateTime(2000);
+          final bDate = b.createdAt ?? DateTime(2000);
+          return aDate.compareTo(bDate);
+        });
         break;
     }
 

lib/features/products/presentation/providers/filtered_products_provider.g.dart

@@ -131,7 +131,7 @@ final class SortedProductsProvider
   }
 }
 
-String _$sortedProductsHash() => r'653f1e9af8c188631dadbfe9ed7d944c6876d2d3';
+String _$sortedProductsHash() => r'8a526ae12a15ca7decc8880ebbd083df455875a8';
 
 /// Provider for sorted products
 /// Adds sorting capability on top of filtered products