feat: implement idempotency key for critical API endpoints

lib/application/order/order_form/order_form_bloc.dart

@@ -3,6 +3,7 @@ import 'package:dartz/dartz.dart' hide Order;
 import 'package:flutter/foundation.dart';
 import 'package:freezed_annotation/freezed_annotation.dart';
 import 'package:injectable/injectable.dart' hide Order;
+import 'package:uuid/uuid.dart';
 
 import '../../../common/types/order_type.dart';
 import '../../../domain/customer/customer.dart';
@@ -123,10 +124,15 @@ class OrderFormBloc extends Bloc<OrderFormEvent, OrderFormState> {
       addItemOrder: (e) async {
         Either<OrderFailure, Order> failureOrAddItemOrder;
 
+        // Generate new idempotency key saat user intent (tap Add Items)
+        // Kalau sedang retry, pakai key yang sama
+        final idempotencyKey = state.addItemIdempotencyKey ?? const Uuid().v4();
+
         emit(
           state.copyWith(
             isAddingItemOrder: true,
             failureOrAddItemOrder: none(),
+            addItemIdempotencyKey: idempotencyKey,
           ),
         );
 
@@ -145,12 +151,16 @@ class OrderFormBloc extends Bloc<OrderFormEvent, OrderFormState> {
         failureOrAddItemOrder = await _repository.addItemOrder(
           id: e.orderId,
           request: request,
+          idempotencyKey: idempotencyKey,
         );
 
         emit(
           state.copyWith(
             isAddingItemOrder: false,
             failureOrAddItemOrder: optionOf(failureOrAddItemOrder),
+            // Clear key on success, keep on failure for retry
+            addItemIdempotencyKey:
+                failureOrAddItemOrder.isRight() ? null : idempotencyKey,
           ),
         );
       },

lib/application/order/order_form/order_form_bloc.freezed.dart

@@ -1584,6 +1584,11 @@ mixin _$OrderFormState {
   bool get isCreatingWithPayment => throw _privateConstructorUsedError;
   bool get isAddingItemOrder => throw _privateConstructorUsedError;
 
+  /// Idempotency key untuk add item order.
+  /// Di-generate saat user tap "Add Items", dipakai ulang saat retry,
+  /// di-clear setelah sukses.
+  String? get addItemIdempotencyKey => throw _privateConstructorUsedError;
+
   /// Create a copy of OrderFormState
   /// with the given fields replaced by the non-null parameter values.
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -1608,6 +1613,7 @@ abstract class $OrderFormStateCopyWith<$Res> {
     bool isCreating,
     bool isCreatingWithPayment,
     bool isAddingItemOrder,
+    String? addItemIdempotencyKey,
   });
 
   $PaymentMethodCopyWith<$Res>? get paymentMethod;
@@ -1638,6 +1644,7 @@ class _$OrderFormStateCopyWithImpl<$Res, $Val extends OrderFormState>
     Object? isCreating = null,
     Object? isCreatingWithPayment = null,
     Object? isAddingItemOrder = null,
+    Object? addItemIdempotencyKey = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -1678,6 +1685,10 @@ class _$OrderFormStateCopyWithImpl<$Res, $Val extends OrderFormState>
                 ? _value.isAddingItemOrder
                 : isAddingItemOrder // ignore: cast_nullable_to_non_nullable
                       as bool,
+            addItemIdempotencyKey: freezed == addItemIdempotencyKey
+                ? _value.addItemIdempotencyKey
+                : addItemIdempotencyKey // ignore: cast_nullable_to_non_nullable
+                      as String?,
           )
           as $Val,
     );
@@ -1731,6 +1742,7 @@ abstract class _$$OrderFormStateImplCopyWith<$Res>
     bool isCreating,
     bool isCreatingWithPayment,
     bool isAddingItemOrder,
+    String? addItemIdempotencyKey,
   });
 
   @override
@@ -1762,6 +1774,7 @@ class __$$OrderFormStateImplCopyWithImpl<$Res>
     Object? isCreating = null,
     Object? isCreatingWithPayment = null,
     Object? isAddingItemOrder = null,
+    Object? addItemIdempotencyKey = freezed,
   }) {
     return _then(
       _$OrderFormStateImpl(
@@ -1801,6 +1814,10 @@ class __$$OrderFormStateImplCopyWithImpl<$Res>
             ? _value.isAddingItemOrder
             : isAddingItemOrder // ignore: cast_nullable_to_non_nullable
                   as bool,
+        addItemIdempotencyKey: freezed == addItemIdempotencyKey
+            ? _value.addItemIdempotencyKey
+            : addItemIdempotencyKey // ignore: cast_nullable_to_non_nullable
+                  as String?,
       ),
     );
   }
@@ -1821,6 +1838,7 @@ class _$OrderFormStateImpl
     this.isCreating = false,
     this.isCreatingWithPayment = false,
     this.isAddingItemOrder = false,
+    this.addItemIdempotencyKey,
   });
 
   @override
@@ -1845,9 +1863,15 @@ class _$OrderFormStateImpl
   @JsonKey()
   final bool isAddingItemOrder;
 
+  /// Idempotency key untuk add item order.
+  /// Di-generate saat user tap "Add Items", dipakai ulang saat retry,
+  /// di-clear setelah sukses.
+  @override
+  final String? addItemIdempotencyKey;
+
   @override
   String toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) {
-    return 'OrderFormState(paymentMethod: $paymentMethod, customerName: $customerName, customer: $customer, failureOrCreateOrder: $failureOrCreateOrder, failureOrCreateOrderWithPayment: $failureOrCreateOrderWithPayment, failureOrAddItemOrder: $failureOrAddItemOrder, isCreating: $isCreating, isCreatingWithPayment: $isCreatingWithPayment, isAddingItemOrder: $isAddingItemOrder)';
+    return 'OrderFormState(paymentMethod: $paymentMethod, customerName: $customerName, customer: $customer, failureOrCreateOrder: $failureOrCreateOrder, failureOrCreateOrderWithPayment: $failureOrCreateOrderWithPayment, failureOrAddItemOrder: $failureOrAddItemOrder, isCreating: $isCreating, isCreatingWithPayment: $isCreatingWithPayment, isAddingItemOrder: $isAddingItemOrder, addItemIdempotencyKey: $addItemIdempotencyKey)';
   }
 
   @override
@@ -1868,7 +1892,10 @@ class _$OrderFormStateImpl
       ..add(DiagnosticsProperty('failureOrAddItemOrder', failureOrAddItemOrder))
       ..add(DiagnosticsProperty('isCreating', isCreating))
       ..add(DiagnosticsProperty('isCreatingWithPayment', isCreatingWithPayment))
-      ..add(DiagnosticsProperty('isAddingItemOrder', isAddingItemOrder));
+      ..add(DiagnosticsProperty('isAddingItemOrder', isAddingItemOrder))
+      ..add(
+        DiagnosticsProperty('addItemIdempotencyKey', addItemIdempotencyKey),
+      );
   }
 
   @override
@@ -1897,7 +1924,9 @@ class _$OrderFormStateImpl
             (identical(other.isCreatingWithPayment, isCreatingWithPayment) ||
                 other.isCreatingWithPayment == isCreatingWithPayment) &&
             (identical(other.isAddingItemOrder, isAddingItemOrder) ||
-                other.isAddingItemOrder == isAddingItemOrder));
+                other.isAddingItemOrder == isAddingItemOrder) &&
+            (identical(other.addItemIdempotencyKey, addItemIdempotencyKey) ||
+                other.addItemIdempotencyKey == addItemIdempotencyKey));
   }
 
   @override
@@ -1912,6 +1941,7 @@ class _$OrderFormStateImpl
     isCreating,
     isCreatingWithPayment,
     isAddingItemOrder,
+    addItemIdempotencyKey,
   );
 
   /// Create a copy of OrderFormState
@@ -1938,6 +1968,7 @@ abstract class _OrderFormState implements OrderFormState {
     final bool isCreating,
     final bool isCreatingWithPayment,
     final bool isAddingItemOrder,
+    final String? addItemIdempotencyKey,
   }) = _$OrderFormStateImpl;
 
   @override
@@ -1959,6 +1990,12 @@ abstract class _OrderFormState implements OrderFormState {
   @override
   bool get isAddingItemOrder;
 
+  /// Idempotency key untuk add item order.
+  /// Di-generate saat user tap "Add Items", dipakai ulang saat retry,
+  /// di-clear setelah sukses.
+  @override
+  String? get addItemIdempotencyKey;
+
   /// Create a copy of OrderFormState
   /// with the given fields replaced by the non-null parameter values.
   @override

lib/application/order/order_form/order_form_state.dart

@@ -13,6 +13,10 @@ class OrderFormState with _$OrderFormState {
     @Default(false) bool isCreating,
     @Default(false) bool isCreatingWithPayment,
     @Default(false) bool isAddingItemOrder,
+    /// Idempotency key untuk add item order.
+    /// Di-generate saat user tap "Add Items", dipakai ulang saat retry,
+    /// di-clear setelah sukses.
+    String? addItemIdempotencyKey,
   }) = _OrderFormState;
 
   factory OrderFormState.initial() => OrderFormState(