feat: dukung penjualan produk per timbangan

Produk kini punya cara jual `unit` (cacah) atau `weight` (timbangan),
mengikuti kontrak backend di docs/integration-weight-based-products.md.

- tipe SellBy, domain/infrastructure unit baru, dan endpoint /api/v1/units
- dialog input berat saat produk timbangan ditambahkan ke keranjang
- tiap penimbangan jadi baris keranjang sendiri; total baris dihitung
  berat x harga satuan, sedangkan produk cacah tetap digabung
- request ke backend mengirim quantity 1 dan membawa berat
- migrasi DB v3: kolom sell_by, unit_id, unit_name, unit_abbreviation
  di tabel products supaya satuan tetap tampil saat offline
- tampilan keranjang, struk, split bill, void, dan refund memakai berat
- test/weight_based_products_test.dart menutup perilaku di atas (9 test)

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/integration-weight-based-products.md

@@ -0,0 +1,279 @@
+# Integrasi Produk Timbangan — POS Mobile & Backoffice
+
+**Migrasi:** `000089` · **Base URL:** `/api/v1` · **Kompatibilitas:** mundur penuh
+
+Panduan untuk menjual produk per timbangan (ikan, daging, buah) dari sisi klien.
+Alasan di balik setiap keputusan desain ada di [`rfc-weight-based-products.md`](./rfc-weight-based-products.md).
+
+---
+
+## 1. Konsep inti
+
+**Satu penimbangan = satu baris order.**
+
+Pelanggan memesan Ikan Tude 4,2 ons, lalu memesan Ikan Tude lagi 5,6 ons. Itu **dua
+baris terpisah**, karena keduanya dua ikan berbeda yang ditimbang sendiri-sendiri.
+
+| Bukan begini | Melainkan begini |
+|---|---|
+| `quantity: 9.8` | `quantity: 1, weight: 4.2`<br>`quantity: 1, weight: 5.6` |
+| Dua ikan hilang jejaknya, dan `quantity` bertipe integer sehingga pecahan ditolak | Tiap penimbangan berdiri sendiri, bisa di-void atau dibayar terpisah |
+
+Empat aturan yang berlaku di seluruh dokumen ini:
+
+1. `quantity` untuk produk timbangan **selalu 1**. Backend memaksanya, dan database
+   menolak nilai lain lewat constraint `chk_order_items_weight_single_line`.
+2. `weight` menyimpan angka timbangan, dalam satuan produk itu sendiri (ons, kg, gram —
+   apa pun yang dipilih saat setup).
+3. Harga baris dihitung `weight × unit_price`, bukan `quantity × unit_price`.
+   `unit_price` tetap berarti harga per satu satuan (per ons).
+4. **Jangan pernah menggabungkan dua baris** produk timbangan menjadi satu, meski
+   produknya sama.
+
+Untuk produk biasa tidak ada yang berubah: `weight` tidak dikirim, `quantity` tetap
+cacah seperti sekarang.
+
+---
+
+## 2. Backoffice — setup produk
+
+### 2.1 Pastikan satuannya ada
+
+Satuan disimpan per organisasi. Buat sekali, pakai ulang untuk semua produk timbangan.
+
+`POST /api/v1/units`
+
+```json
+{
+  "name": "Ons",
+  "abbreviation": "ons",
+  "is_active": true
+}
+```
+
+`abbreviation` yang dipakai POS untuk mencetak `4,2 ons` di struk — isi dengan bentuk
+pendek yang benar-benar ingin ditampilkan. Daftar satuan dibaca lewat `GET /api/v1/units`.
+
+### 2.2 Buat produk sebagai produk timbangan
+
+`POST /api/v1/products`
+
+```json
+{
+  "category_id": "…",
+  "name": "Ikan Tude",
+  "price": 4500,
+  "cost": 3000,
+  "sell_by": "weight",
+  "unit_id": "<id satuan Ons>"
+}
+```
+
+| Field | Tipe | Keterangan |
+|---|---|---|
+| `sell_by` | `"unit"` \| `"weight"` | Opsional, default `"unit"`. Nilai lain **ditolak** dengan pesan jelas. |
+| `unit_id` | UUID | **Wajib** saat `sell_by: "weight"`, ditolak backend bila kosong. Opsional untuk produk satuan. |
+| `price` | number | Harga per satu satuan. Rp 4.500 per ons, bukan harga per ikan. |
+
+Pada `PUT /api/v1/products/:id`, `unit_id` **tidak perlu dikirim ulang** bila produknya
+sudah punya satuan — mengubah `sell_by` menjadi `"weight"` saja sudah cukup. Yang ditolak
+adalah kondisi akhirnya: produk yang dijual per timbangan tanpa satuan.
+
+Keduanya juga bisa diubah lewat `PUT /api/v1/products/:id` dengan bentuk yang sama, dan
+ikut terbaca di setiap response produk (`GET /api/v1/products`, `/products/all`,
+`/products/:id`).
+
+### 2.3 Catatan UI
+
+- Kunci `sell_by` **setelah produk punya transaksi**. Mengubah produk lama dari `unit`
+  ke `weight` tidak mengubah baris order yang sudah ada — baris lama tetap dihitung per
+  cacah — tapi akan membingungkan pengguna yang melihat riwayatnya.
+- Saat `weight` dipilih, jadikan pemilih satuan sebagai field **wajib** di form. Backend
+  juga menolaknya, tapi ditangkap di form lebih baik daripada baru gagal saat simpan.
+- Ubah label harga mengikuti satuan yang dipilih: *"Harga per ons"*.
+- Untuk produk satuan, pemilih satuan boleh disembunyikan — `unit_id` opsional dan belum
+  dikonsumsi apa pun di POS.
+
+---
+
+## 3. POS Mobile — transaksi
+
+### 3.1 Bentuk input mengikuti `sell_by`
+
+| `sell_by` | Input di POS | Yang dikirim |
+|---|---|---|
+| `"unit"` | Stepper − / + seperti sekarang | `quantity: n`, tanpa `weight` |
+| `"weight"` | Papan angka desimal, satuan dari `unit` produk | `quantity: 1` + `weight: 4.2` |
+
+### 3.2 Mengirim order
+
+`POST /api/v1/orders`
+
+```json
+{
+  "outlet_id": "…",
+  "user_id": "…",
+  "order_type": "dine_in",
+  "order_items": [
+    { "product_id": "<ikan-tude>",  "quantity": 1, "weight": 4.2 },
+    { "product_id": "<ikan-tude>",  "quantity": 1, "weight": 5.6 },
+    { "product_id": "<nasi-goreng>", "quantity": 2 }
+  ]
+}
+```
+
+Bentuk yang sama berlaku untuk `POST /api/v1/orders/:id/add-items` dan untuk pemesanan
+mandiri `POST /api/v1/self-order/orders`.
+
+**Presisi.** Berat dibulatkan backend ke 3 desimal. Kirim `4.2` atau `4.237`; angka di
+bawah `0.001` membulat ke nol dan ditolak.
+
+**Harga.** Field `unit_price` pada request **diabaikan** — harga selalu diambil backend
+dari master produk. Jangan mengirim harga hasil hitungan sendiri.
+
+---
+
+## 4. Menampilkan baris
+
+Setiap `order_items[]` di response membawa empat field tambahan:
+
+```json
+{
+  "product_name": "Ikan Tude",
+  "quantity": 1,
+  "weight": 4.2,
+  "unit_id": "…",
+  "unit_name": "Ons",
+  "unit_abbreviation": "ons",
+  "unit_price": 4500,
+  "total_price": 18900
+}
+```
+
+Semuanya `null` atau absen untuk produk biasa, jadi cabangkan tampilan pada `weight`:
+
+| Kondisi | Tampilkan |
+|---|---|
+| `weight == null` | `2 × Rp 25.000` |
+| `weight != null` | `4,2 ons × Rp 4.500` |
+
+**Jangan menampilkan `quantity` untuk baris berbobot** — nilainya selalu 1 dan akan
+terbaca seperti "satu ons". Gunakan `weight` dengan `unit_abbreviation`, dan pakai koma
+desimal sesuai format Indonesia.
+
+---
+
+## 5. Void, refund, split bill
+
+Baris berbobot bersifat **utuh**: dibatalkan seluruhnya atau tidak sama sekali. Karena
+`quantity`-nya 1, semua endpoint cukup dikirimi `1`, dan backend menghitung nilai
+rupiahnya dari `weight`.
+
+| Aksi | Endpoint | Field untuk baris berbobot |
+|---|---|---|
+| Void per item | `POST /orders/void` | `items[].quantity: 1` |
+| Refund per item | `POST /orders/:id/refund` | `order_items[].refund_quantity: 1` (atau kosongkan) |
+| Split bill per item | `POST /orders/split-bill` | `items[].quantity: 1` = bayar baris itu penuh |
+
+```json
+{
+  "order_id": "…",
+  "reason": "Salah timbang",
+  "type": "ITEM",
+  "items": [
+    { "order_item_id": "<baris 4,2 ons>", "quantity": 1 }
+  ]
+}
+```
+
+Untuk split bill, baris berbobot hanya bisa berstatus belum dibayar atau lunas — tidak
+ada nilai di antaranya. Sembunyikan stepper jumlah pada baris berbobot, ganti dengan
+tombol pilih baris.
+
+**Batasan yang disengaja.** Mengembalikan *sebagian berat* — 1 ons dari baris 4,2 ons —
+tidak didukung. Koreksi salah timbang ditangani dengan void baris itu lalu input ulang,
+sehingga jejak auditnya tetap jujur.
+
+---
+
+## 6. Referensi error
+
+Semua error mengikuti amplop standar. Pesan validasi baru muncul dengan kode `900`:
+
+```json
+{
+  "success": false,
+  "data": null,
+  "errors": [
+    { "code": "900", "entity": "ORDER",
+      "cause": "product Ikan Tude is sold by weight and requires a weight" }
+  ]
+}
+```
+
+| Pesan (`cause`) | Penyebab | Perbaikan di klien |
+|---|---|---|
+| `… is sold by weight and requires a weight` | Produk `sell_by: "weight"` dikirim tanpa `weight` | Wajibkan input timbangan sebelum item masuk keranjang |
+| `… is not sold by weight and must not carry a weight` | `weight` dikirim untuk produk satuan | Kirim `weight` hanya bila `sell_by == "weight"` |
+| `weight for … must be greater than 0` | Berat nol, negatif, atau membulat ke nol | Validasi minimal `0.001` di keypad |
+| `quantity for … must be at least 1` | Produk satuan dengan `quantity` ≤ 0 | Perilaku lama, tidak berubah |
+
+Pesan menyebut **nama produk**, sehingga bisa ditampilkan apa adanya ke kasir.
+
+### Setup produk (Backoffice)
+
+| Pesan (`cause`) | Penyebab | Perbaikan di klien |
+|---|---|---|
+| `unit_id is required when sell_by is 'weight'` | Produk timbangan dibuat tanpa satuan | Wajibkan pemilih satuan saat Timbangan dipilih |
+| `sell_by must be either 'unit' or 'weight'` | Nilai `sell_by` di luar dua itu | Kirim persis `"unit"` atau `"weight"` |
+| `product '…' is sold by weight and requires a unit_id` | Update membuat produk jadi timbangan tanpa satuan | Kirim `unit_id` bersama perubahan `sell_by` |
+
+---
+
+## 7. Kompatibilitas mundur
+
+- Semua produk lama otomatis `sell_by: "unit"`. Perilakunya identik dengan sebelumnya.
+- `weight` opsional di request. Klien yang tidak mengenalnya tetap berfungsi penuh untuk
+  produk satuan.
+- Field baru di response semuanya `omitempty` — tidak muncul untuk baris biasa, jadi
+  parser lama tidak terganggu.
+- `quantity` tetap **integer** di seluruh API. Tidak ada field yang berubah tipe.
+
+Yang tidak berfungsi di klien lama hanyalah menjual produk timbangan itu sendiri —
+permintaannya ditolak dengan pesan jelas, bukan gagal diam-diam.
+
+---
+
+## 8. Batasan yang diketahui
+
+- **Pembulatan uang ke 2 desimal.** `4,237 ons × Rp 4.500` tersimpan `Rp 19.066,50`,
+  bukan dibulatkan ke rupiah utuh. Bila kasir harus menerima rupiah penuh, ini perlu
+  diputuskan dan diubah di backend lebih dulu (`RoundMoney`, satu tempat).
+- **Stok belum otomatis berkurang** saat penjualan — untuk produk timbangan maupun
+  produk biasa. Pengurangan stok belum tersambung di backend, jadi jangan menampilkan
+  sisa stok yang mengandaikan itu berjalan.
+
+---
+
+## 9. Checklist per tim
+
+**Backoffice Website**
+
+- [ ] CRUD satuan tersedia di menu master data
+- [ ] Form produk punya pilihan cara jual: Satuan / Timbangan
+- [ ] Pemilih satuan menjadi wajib saat Timbangan dipilih
+- [ ] Label harga ikut satuan — "Harga per ons"
+- [ ] `sell_by` dikunci untuk produk yang sudah bertransaksi
+- [ ] Daftar produk menandai mana yang dijual per timbangan
+- [ ] Laporan harian menampilkan kolom Berat
+
+**POS Mobile**
+
+- [ ] Menu membaca `sell_by` tiap produk
+- [ ] Papan angka desimal untuk produk timbangan
+- [ ] Kirim `quantity: 1` + `weight`
+- [ ] Dua penimbangan menjadi dua baris, tidak digabung
+- [ ] Keranjang & struk menampilkan `4,2 ons × Rp 4.500`
+- [ ] Void & refund baris berbobot bersifat utuh
+- [ ] Split bill: pilih baris, bukan stepper jumlah
+- [ ] Pesan error validasi ditampilkan ke kasir

lib/application/auth/login_form/login_form_bloc.dart

@@ -6,6 +6,7 @@ import 'package:freezed_annotation/freezed_annotation.dart';
 import 'package:injectable/injectable.dart';
 
 import '../../../common/service/device_info_service.dart';
+import '../../../common/service/unit_registry.dart';
 import '../../../common/service/fcm_service.dart';
 import '../../../domain/auth/auth.dart';
 
@@ -18,11 +19,13 @@ class LoginFormBloc extends Bloc<LoginFormEvent, LoginFormState> {
   final IAuthRepository _authRepository;
   final FcmService _fcmService;
   final DeviceInfoService _deviceInfoService;
+  final UnitRegistry _unitRegistry;
 
   LoginFormBloc(
     this._authRepository,
     this._fcmService,
     this._deviceInfoService,
+    this._unitRegistry,
   ) : super(LoginFormState.initial()) {
     on<LoginFormEvent>(_onLoginFormEvent);
   }
@@ -62,6 +65,12 @@ class LoginFormBloc extends Bloc<LoginFormEvent, LoginFormState> {
             devicePayload: devicePayload,
           );
 
+          // Master satuan diambil sekali per sesi supaya keranjang bisa
+          // menulis "4,2 ons" tanpa menunggu request saat kasir menimbang.
+          if (failureOrLogin.isRight()) {
+            await _unitRegistry.load(forceRefresh: true);
+          }
+
           emit(
             state.copyWith(
               isSubmitting: false,

lib/application/checkout/checkout_form/checkout_form_bloc.dart

@@ -3,6 +3,7 @@ import 'dart:developer';
 import 'package:bloc/bloc.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/delivery/delivery.dart';
@@ -19,6 +20,33 @@ class CheckoutFormBloc extends Bloc<CheckoutFormEvent, CheckoutFormState> {
   CheckoutFormBloc() : super(CheckoutFormState.initial()) {
     on<CheckoutFormEvent>(_onCheckoutFormEvent);
   }
+
+  /// Baris berbobot dihitung `weight × harga`, baris cacah `quantity × harga`.
+  /// Satu tempat saja supaya total keranjang, subtotal, dan ringkasan tidak
+  /// pernah berbeda hitungan.
+  CheckoutFormState _recalculate(
+    CheckoutFormState state,
+    List<ProductQuantity> items,
+  ) {
+    final totalQuantity = items.fold<int>(
+      0,
+      // Baris berbobot selalu satu penimbangan, jadi dihitung satu.
+      (sum, item) => sum + (item.isWeighted ? 1 : item.quantity),
+    );
+
+    final totalPrice = items.fold<double>(
+      0,
+      (sum, item) => sum + item.lineTotal,
+    );
+
+    return state.copyWith(
+      items: items,
+      totalQuantity: totalQuantity,
+      totalPrice: totalPrice.toInt(),
+      isLoading: false,
+    );
+  }
+
   Future<void> _onCheckoutFormEvent(
     CheckoutFormEvent event,
     Emitter<CheckoutFormState> emit,
@@ -26,12 +54,21 @@ class CheckoutFormBloc extends Bloc<CheckoutFormEvent, CheckoutFormState> {
     return event.map(
       addItem: (e) async {
         final currentState = state;
+
+        // Produk timbangan tidak punya stepper — masuk lewat addWeightedItem
+        // setelah kasir memasukkan angka timbangan.
+        if (e.product.isSoldByWeight) {
+          log('⚖️ ${e.product.name} dijual per timbangan, butuh berat');
+          return;
+        }
+
         emit(currentState.copyWith(isLoading: true));
 
         List<ProductQuantity> items = [...currentState.items];
 
         final index = items.indexWhere(
           (element) =>
+              !element.isWeighted &&
               element.product.id == e.product.id &&
               element.variant?.id == e.variant?.id,
         );
@@ -49,35 +86,47 @@ class CheckoutFormBloc extends Bloc<CheckoutFormEvent, CheckoutFormState> {
               quantity: 1,
               variant: e.variant,
               notes: '',
+              lineId: const Uuid().v4(),
             ),
           );
         }
 
         log('🛒 Items updated: ${items.length} items total ${items.toList()}');
 
-        final totalQuantity = items.fold<int>(
-          0,
-          (sum, item) => sum + item.quantity,
-        );
+        emit(_recalculate(currentState, items));
+      },
+      addWeightedItem: (e) async {
+        final currentState = state;
+        emit(currentState.copyWith(isLoading: true));
 
-        final totalPrice = state.items.isEmpty
-            ? 0.0
-            : state.items
-                  .map(
-                    (e) =>
-                        (e.product.price * e.quantity) +
-                        (e.variant?.priceModifier ?? 0),
-                  )
-                  .reduce((value, element) => value + element);
-
-        emit(
-          currentState.copyWith(
-            items: items,
-            totalQuantity: totalQuantity,
-            totalPrice: totalPrice.toInt(),
-            isLoading: false,
+        // Sengaja tidak digabung dengan baris lain: dua penimbangan adalah dua
+        // ikan berbeda, masing-masing bisa di-void atau dibayar terpisah.
+        final items = [
+          ...currentState.items,
+          ProductQuantity(
+            product: e.product,
+            variant: e.variant,
+            quantity: 1,
+            notes: '',
+            lineId: const Uuid().v4(),
+            weight: e.weight,
           ),
-        );
+        ];
+
+        log('⚖️ Penimbangan baru: ${e.product.name} ${e.weight}');
+
+        emit(_recalculate(currentState, items));
+      },
+      updateItemWeight: (e) async {
+        final currentState = state;
+        final items = [...currentState.items];
+
+        final index = items.indexWhere((item) => item.lineId == e.lineId);
+        if (index == -1) return;
+
+        items[index] = items[index].copyWith(weight: e.weight);
+
+        emit(_recalculate(currentState, items));
       },
       removeItem: (e) async {
         final currentState = state;
@@ -86,6 +135,7 @@ class CheckoutFormBloc extends Bloc<CheckoutFormEvent, CheckoutFormState> {
 
         final index = items.indexWhere(
           (element) =>
+              !element.isWeighted &&
               element.product.id == e.product.id &&
               element.variant?.id == e.variant?.id,
         );
@@ -103,32 +153,18 @@ class CheckoutFormBloc extends Bloc<CheckoutFormEvent, CheckoutFormState> {
           }
         }
 
-        final totalQuantity = items.fold<int>(
-          0,
-          (sum, item) => sum + item.quantity,
-        );
-        final totalPrice = items.fold<int>(
-          0,
-          (sum, item) =>
-              sum +
-              (item.quantity *
-                  (item.variant?.priceModifier.toInt() ??
-                      item.product.price.toInt())),
-        );
+        log('🗑️ Item removed. Total items: ${items.length}');
 
-        log(
-          '🗑️ Item removed. Total items: ${items.length}, totalQuantity: $totalQuantity, totalPrice: $totalPrice',
-        );
+        emit(_recalculate(currentState, items));
+      },
+      removeLine: (e) async {
+        final currentState = state;
+        final items = [...currentState.items]
+          ..removeWhere((item) => item.lineId == e.lineId);
 
-        // Emit state baru
-        emit(
-          currentState.copyWith(
-            items: items,
-            totalQuantity: totalQuantity,
-            totalPrice: totalPrice,
-            isLoading: false,
-          ),
-        );
+        log('🗑️ Baris dihapus. Sisa ${items.length} baris');
+
+        emit(_recalculate(currentState, items));
       },
       started: (e) async {
         emit(CheckoutFormState.initial().copyWith(isLoading: true));
@@ -153,14 +189,13 @@ class CheckoutFormBloc extends Bloc<CheckoutFormEvent, CheckoutFormState> {
           );
         }
       },
-      updateItemNotes: (e) async {
+      updateLineNotes: (e) async {
         final currentState = state;
 
-        // Clone list items agar tidak mutasi langsung
+        // Catatan diikat ke baris, bukan ke produk: dua penimbangan produk yang
+        // sama bisa punya catatan berbeda.
         final items = [...currentState.items];
-        final index = items.indexWhere(
-          (element) => element.product.id == e.product.id,
-        );
+        final index = items.indexWhere((item) => item.lineId == e.lineId);
 
         if (index != -1) {
           items[index] = items[index].copyWith(notes: e.notes);
@@ -181,8 +216,8 @@ class CheckoutFormBloc extends Bloc<CheckoutFormEvent, CheckoutFormState> {
         emit(state.copyWith(orderAdded: e.order));
       },
       customerNameChanged: (e) async {
-        emit(state.copyWith(customerName: e.name,));
-      }
+        emit(state.copyWith(customerName: e.name));
+      },
     );
   }
 }

lib/application/checkout/checkout_form/checkout_form_event.dart

@@ -10,15 +10,32 @@ class CheckoutFormEvent with _$CheckoutFormEvent {
     ProductVariant? variant,
   ) = _AddItem;
 
+  /// Satu penimbangan = satu baris baru. Dipanggil setiap kali kasir selesai
+  /// memasukkan angka timbangan, meski produknya sama dengan baris lain.
+  const factory CheckoutFormEvent.addWeightedItem(
+    Product product,
+    ProductVariant? variant,
+    double weight,
+  ) = _AddWeightedItem;
+
+  /// Koreksi angka timbangan pada satu baris tertentu.
+  const factory CheckoutFormEvent.updateItemWeight(
+    String lineId,
+    double weight,
+  ) = _UpdateItemWeight;
+
   const factory CheckoutFormEvent.removeItem(
     Product product,
     ProductVariant? variant,
   ) = _RemoveItem;
 
-  const factory CheckoutFormEvent.updateItemNotes(
-    Product product,
+  /// Hapus satu baris utuh — satu-satunya cara membatalkan baris berbobot.
+  const factory CheckoutFormEvent.removeLine(String lineId) = _RemoveLine;
+
+  const factory CheckoutFormEvent.updateLineNotes(
+    String lineId,
     String notes,
-  ) = _UpdateItemNotes;
+  ) = _UpdateLineNotes;
 
   const factory CheckoutFormEvent.updateOrderType(OrderType orderType) =
       _UpdateOrderType;

lib/application/order/order_form/order_form_bloc.dart

@@ -60,15 +60,7 @@ class OrderFormBloc extends Bloc<OrderFormEvent, OrderFormState> {
           notes: '',
           customerName: state.customerName ?? "",
           orderItems: e.items
-              .map(
-                (item) => OrderItemRequest(
-                  productId: item.product.id,
-                  productVariantId: item.variant?.id ?? "",
-                  quantity: item.quantity,
-                  unitPrice: item.product.price.toInt(),
-                  notes: item.notes,
-                ),
-              )
+              .map(OrderItemRequest.fromProductQuantity)
               .toList(),
         );
 
@@ -100,15 +92,7 @@ class OrderFormBloc extends Bloc<OrderFormEvent, OrderFormState> {
           notes: '',
           customerName: state.customerName ?? "",
           orderItems: e.items
-              .map(
-                (item) => OrderItemRequest(
-                  productId: item.product.id,
-                  productVariantId: item.variant?.id ?? "",
-                  quantity: item.quantity,
-                  unitPrice: item.product.price.toInt(),
-                  notes: item.notes,
-                ),
-              )
+              .map(OrderItemRequest.fromProductQuantity)
               .toList(),
         );
 
@@ -137,15 +121,7 @@ class OrderFormBloc extends Bloc<OrderFormEvent, OrderFormState> {
         );
 
         final request = e.items
-            .map(
-              (item) => AddItemOrderRequest(
-                productId: item.product.id,
-                productVariantId: item.variant?.id ?? '',
-                quantity: item.quantity,
-                unitPrice: item.product.price.toInt(),
-                notes: item.notes,
-              ),
-            )
+            .map(AddItemOrderRequest.fromProductQuantity)
             .toList();
 
         failureOrAddItemOrder = await _repository.addItemOrder(

lib/application/split_bill/split_bill_form/split_bill_form_bloc.dart

@@ -67,7 +67,11 @@ class SplitBillFormBloc extends Bloc<SplitBillFormEvent, SplitBillFormState> {
           final item = state.pendingItems.firstWhere(
             (item) => item.id == entry.key,
           );
-          newTotal += item.unitPrice.toInt() * entry.value;
+          // Baris berbobot dibayar utuh: nilainya weight x harga, bukan
+          // quantity x harga.
+          newTotal += item.isWeighted
+              ? item.totalPrice
+              : item.unitPrice.toInt() * entry.value;
         }
 
         emit(

lib/application/sync/sync_setting/sync_setting_bloc.dart

@@ -3,6 +3,7 @@ import 'package:dartz/dartz.dart';
 import 'package:freezed_annotation/freezed_annotation.dart';
 import 'package:injectable/injectable.dart';
 
+import '../../../common/service/unit_registry.dart';
 import '../../../domain/category/category.dart';
 import '../../../domain/product/product.dart';
 
@@ -14,9 +15,13 @@ part 'sync_setting_bloc.freezed.dart';
 class SyncSettingBloc extends Bloc<SyncSettingEvent, SyncSettingState> {
   final IProductRepository _productRepository;
   final ICategoryRepository _categoryRepository;
+  final UnitRegistry _unitRegistry;
 
-  SyncSettingBloc(this._productRepository, this._categoryRepository)
-    : super(SyncSettingState.initial()) {
+  SyncSettingBloc(
+    this._productRepository,
+    this._categoryRepository,
+    this._unitRegistry,
+  ) : super(SyncSettingState.initial()) {
     on<SyncSettingEvent>(_onSyncSettingEvent);
   }
 
@@ -97,6 +102,10 @@ class SyncSettingBloc extends Bloc<SyncSettingEvent, SyncSettingState> {
       ),
     );
 
+    // Satuan lebih dulu: produk timbangan butuh singkatannya untuk bisa
+    // ditulis "4,2 ons" begitu selesai disinkronkan.
+    await _unitRegistry.load(forceRefresh: true);
+
     // Sync categories first
     final categoryResult = await _categoryRepository.syncAllCategories();
 
@@ -169,6 +178,8 @@ class SyncSettingBloc extends Bloc<SyncSettingEvent, SyncSettingState> {
   Future<void> _onSyncProducts(Emitter<SyncSettingState> emit) async {
     emit(state.copyWith(isLoading: true, failureOptionSyncProduct: none()));
 
+    await _unitRegistry.load(forceRefresh: true);
+
     final result = await _productRepository.syncAllProducts();
 
     result.fold(

lib/application/void/void_form/void_form_bloc.dart

@@ -55,7 +55,10 @@ class VoidFormBloc extends Bloc<VoidFormEvent, VoidFormState> {
             (item) => item.id == entry.key,
           );
           if (item == null) continue;
-          newTotal += item.unitPrice.toInt() * entry.value;
+          // Baris berbobot di-void utuh; rupiahnya sudah weight x harga.
+          newTotal += item.isWeighted
+              ? item.totalPrice
+              : item.unitPrice.toInt() * entry.value;
         }
 
         emit(
@@ -92,7 +95,13 @@ class VoidFormBloc extends Bloc<VoidFormEvent, VoidFormState> {
                 productVariantName: originalItem.productVariantName,
                 quantity: voidQty,
                 unitPrice: originalItem.unitPrice,
-                totalPrice: (originalItem.unitPrice) * voidQty,
+                totalPrice: originalItem.isWeighted
+                    ? originalItem.totalPrice
+                    : (originalItem.unitPrice) * voidQty,
+                weight: originalItem.weight,
+                unitId: originalItem.unitId,
+                unitName: originalItem.unitName,
+                unitAbbreviation: originalItem.unitAbbreviation,
                 modifiers: originalItem.modifiers,
                 notes: originalItem.notes,
                 status: originalItem.status,

lib/common/constant/local_storage_key.dart

@@ -2,4 +2,5 @@ class LocalStorageKey {
   static const String token = 'token';
   static const String user = 'user';
   static const String outlet = 'outlet';
+  static const String units = 'units';
 }

lib/common/database/database_helper.dart

@@ -17,7 +17,7 @@ class DatabaseHelper {
 
     return await openDatabase(
       path,
-      version: 2,
+      version: 3,
       onCreate: _onCreate,
       onUpgrade: _onUpgrade,
     );
@@ -42,7 +42,11 @@ class DatabaseHelper {
         metadata TEXT,
         is_active INTEGER,
         created_at TEXT,
-        updated_at TEXT
+        updated_at TEXT,
+        sell_by TEXT DEFAULT 'unit',
+        unit_id TEXT,
+        unit_name TEXT,
+        unit_abbreviation TEXT
       )
     ''');
 
@@ -114,6 +118,17 @@ class DatabaseHelper {
         'ALTER TABLE products ADD COLUMN print_to_checker INTEGER DEFAULT 0',
       );
     }
+
+    // Produk timbangan: cara jual dan satuan ikut disimpan lokal supaya POS
+    // tetap bisa menampilkan "4,2 ons" saat offline.
+    if (oldVersion < 3) {
+      await db.execute(
+        "ALTER TABLE products ADD COLUMN sell_by TEXT DEFAULT 'unit'",
+      );
+      await db.execute('ALTER TABLE products ADD COLUMN unit_id TEXT');
+      await db.execute('ALTER TABLE products ADD COLUMN unit_name TEXT');
+      await db.execute('ALTER TABLE products ADD COLUMN unit_abbreviation TEXT');
+    }
   }
 
   Future<void> close() async {

lib/common/extension/double_extension.dart

@@ -13,3 +13,10 @@ extension DoubleExt on double {
     decimalDigits: 0,
   ).format(this);
 }
+
+extension WeightExt on double {
+  /// Format berat gaya Indonesia: koma desimal, tanpa nol di belakang.
+  /// `4.2` → `4,2`, `4.237` → `4,237`, `5.0` → `5`.
+  String get weightFormat =>
+      NumberFormat('#,##0.###', 'id').format(this);
+}

lib/common/function/app_function.dart

@@ -75,3 +75,25 @@ int generateRandomNumber() {
   final random = Random();
   return 1 + random.nextInt(10000);
 }
+
+/// Ambil pesan validasi dari amplop error standar backend.
+///
+/// Untuk produk timbangan pesannya menyebut nama produk — misalnya
+/// "product Ikan Tude is sold by weight and requires a weight" — jadi layak
+/// ditampilkan apa adanya ke kasir alih-alih diganti pesan generik.
+String? extractApiErrorCause(dynamic responseData) {
+  if (responseData is! Map) return null;
+
+  final errors = responseData['errors'];
+  if (errors is! List || errors.isEmpty) return null;
+
+  final causes = errors
+      .whereType<Map>()
+      .map((e) => (e['cause'] ?? e['message'])?.toString())
+      .where((cause) => cause != null && cause.isNotEmpty)
+      .cast<String>()
+      .toList();
+
+  if (causes.isEmpty) return null;
+  return causes.join('\n');
+}

lib/common/service/unit_registry.dart

@@ -0,0 +1,48 @@
+import 'dart:developer';
+
+import 'package:injectable/injectable.dart';
+
+import '../../domain/unit/unit.dart';
+
+/// Kamus satuan yang dipakai untuk menerjemahkan `unit_id` sebuah produk
+/// menjadi singkatan yang dicetak di keranjang dan struk (`4,2 ons`).
+///
+/// Response produk hanya dijamin membawa `unit_id`; nama dan singkatannya
+/// datang dari `GET /api/v1/units`. Registry ini menjembatani keduanya tanpa
+/// memaksa setiap pemanggil menunggu request.
+@lazySingleton
+class UnitRegistry {
+  final IUnitRepository _repository;
+  final _logName = 'UnitRegistry';
+
+  Map<String, ProductUnit> _unitsById = {};
+
+  UnitRegistry(this._repository);
+
+  bool get isEmpty => _unitsById.isEmpty;
+
+  ProductUnit? byId(String? id) {
+    if (id == null || id.isEmpty) return null;
+    return _unitsById[id];
+  }
+
+  String abbreviationOf(String? id) => byId(id)?.abbreviation ?? '';
+
+  String nameOf(String? id) => byId(id)?.name ?? '';
+
+  /// Muat satuan ke memori. Aman dipanggil berulang; [forceRefresh] menembak
+  /// server ulang saat pengguna melakukan sinkronisasi manual.
+  Future<void> load({bool forceRefresh = false}) async {
+    final result = await _repository.getUnits(forceRefresh: forceRefresh);
+
+    result.fold(
+      (failure) => log('⚠️ Gagal memuat satuan: $failure', name: _logName),
+      (units) {
+        _unitsById = {for (final unit in units) unit.id: unit};
+        log('📏 ${units.length} satuan siap dipakai', name: _logName);
+      },
+    );
+  }
+
+  void clear() => _unitsById = {};
+}

lib/common/types/sell_by.dart

@@ -0,0 +1,19 @@
+/// Cara sebuah produk dijual.
+///
+/// Lihat `docs/integration-weight-based-products.md` — backend hanya menerima
+/// dua nilai ini, dan produk lama otomatis dianggap [SellBy.unit].
+class SellBy {
+  const SellBy._();
+
+  /// Dijual per cacah. `quantity` integer, `weight` tidak dikirim.
+  static const String unit = 'unit';
+
+  /// Dijual per timbangan. `quantity` selalu 1, `weight` wajib.
+  static const String weight = 'weight';
+
+  static bool isWeight(String? value) => value == weight;
+
+  /// Nilai apa pun di luar dua yang dikenal diperlakukan sebagai [unit],
+  /// sama seperti perilaku backend untuk produk lama.
+  static String normalize(String? value) => value == weight ? weight : unit;
+}

lib/common/url/api_path.dart

@@ -4,6 +4,7 @@ class ApiPath {
   static const String outlets = '/api/v1/outlets';
   static const String categories = '/api/v1/categories';
   static const String products = '/api/v1/products';
+  static const String units = '/api/v1/units';
   static const String tables = '/api/v1/tables';
   static const String customers = '/api/v1/customers';
   static const String paymentMethods = '/api/v1/payment-methods';

lib/domain/order/entities/add_item_order_request_entity.dart

@@ -8,6 +8,9 @@ class AddItemOrderRequest with _$AddItemOrderRequest {
     required int quantity,
     required int unitPrice,
     required String notes,
+
+    /// Hanya diisi untuk produk `sell_by: "weight"`.
+    double? weight,
   }) = _AddItemOrderRequest;
 
   factory AddItemOrderRequest.empty() => const AddItemOrderRequest(
@@ -17,4 +20,14 @@ class AddItemOrderRequest with _$AddItemOrderRequest {
     unitPrice: 0,
     notes: '',
   );
+
+  factory AddItemOrderRequest.fromProductQuantity(ProductQuantity item) =>
+      AddItemOrderRequest(
+        productId: item.product.id,
+        productVariantId: item.variant?.id ?? '',
+        quantity: item.isWeighted ? 1 : item.quantity,
+        unitPrice: item.product.price.toInt(),
+        notes: item.notes,
+        weight: item.weight,
+      );
 }

lib/domain/order/entities/order_entity.dart

@@ -197,19 +197,19 @@ class Order with _$Order {
   );
 
   // For Add Item Order
-  factory Order.fromLastOrder(Order order, List<ProductQuantity> products) =>
-      order.copyWith(
-        orderItems: products
-            .map((e) => OrderItem.fromProductQuantity(e))
-            .toList(),
-        totalAmount: products
-            .map((e) => e.product.price.toInt() * e.quantity)
-            .reduce((value, element) => value + element),
-            subtotal: products
-            .map((e) => e.product.price.toInt() * e.quantity)
-            .reduce((value, element) => value + element),
+  factory Order.fromLastOrder(Order order, List<ProductQuantity> products) {
+    final subtotal = products.fold<int>(
+      0,
+      (sum, item) => sum + item.lineTotal.toInt(),
+    );
+
+    return order.copyWith(
+      orderItems: products.map(OrderItem.fromProductQuantity).toList(),
+      totalAmount: subtotal,
+      subtotal: subtotal,
       metadata: order.metadata,
     );
+  }
 
   List<OrderItem> get orderItemNotCancelled =>
       orderItems.where((item) => item.status != 'cancelled').toList();
@@ -217,6 +217,8 @@ class Order with _$Order {
 
 @freezed
 class OrderItem with _$OrderItem {
+  const OrderItem._();
+
   const factory OrderItem({
     required String id,
     required String orderId,
@@ -237,6 +239,12 @@ class OrderItem with _$OrderItem {
     required int paidQuantity,
     required String categoryId,
     required String categoryName,
+
+    /// Angka timbangan baris ini. `null` untuk produk cacah.
+    double? weight,
+    @Default('') String unitId,
+    @Default('') String unitName,
+    @Default('') String unitAbbreviation,
   }) = _OrderItem;
 
   factory OrderItem.empty() => OrderItem(
@@ -269,10 +277,9 @@ class OrderItem with _$OrderItem {
         productName: productQuantity.product.name,
         productVariantId: productQuantity.variant?.id ?? '',
         productVariantName: productQuantity.variant?.name ?? '',
-        quantity: productQuantity.quantity,
+        quantity: productQuantity.isWeighted ? 1 : productQuantity.quantity,
         unitPrice: productQuantity.product.price.toInt(),
-        totalPrice: (productQuantity.product.price * productQuantity.quantity)
-            .toInt(),
+        totalPrice: productQuantity.lineTotal.toInt(),
         modifiers: [],
         notes: productQuantity.notes,
         status: 'pending',
@@ -283,5 +290,30 @@ class OrderItem with _$OrderItem {
         paidQuantity: 0,
         categoryId: '',
         categoryName: '',
+        weight: productQuantity.weight,
+        unitId: productQuantity.product.unitId,
+        unitName: productQuantity.product.unitName,
+        unitAbbreviation: productQuantity.product.unitAbbreviation,
       );
+
+  /// Baris hasil penimbangan — utuh, tidak bisa dipecah sebagian.
+  bool get isWeighted => weight != null && weight! > 0;
+
+  /// Singkatan satuan untuk ditampilkan; jatuh ke nama panjang bila kosong.
+  String get unitLabel =>
+      unitAbbreviation.isNotEmpty ? unitAbbreviation : unitName;
+
+  /// `4,2 ons` untuk baris berbobot, `2` untuk baris biasa.
+  ///
+  /// Jangan menampilkan [quantity] mentah pada baris berbobot — nilainya selalu
+  /// 1 dan terbaca seperti "satu ons".
+  String get quantityLabel {
+    if (!isWeighted) return quantity.toString();
+    final value = weight!.weightFormat;
+    return unitLabel.isEmpty ? value : '$value $unitLabel';
+  }
+
+  /// `4,2 ons x Rp 4.500` atau `2 x Rp 25.000`.
+  String get quantityPriceLabel =>
+      '$quantityLabel x ${unitPrice.currencyFormatRpV2}';
 }

lib/domain/order/entities/order_request_entity.dart

@@ -33,6 +33,10 @@ class OrderItemRequest with _$OrderItemRequest {
     required int quantity,
     required int unitPrice,
     required String notes,
+
+    /// Hanya diisi untuk produk `sell_by: "weight"`; produk cacah tidak boleh
+    /// mengirim berat sama sekali.
+    double? weight,
   }) = _OrderItemRequest;
 
   factory OrderItemRequest.empty() => const OrderItemRequest(
@@ -42,4 +46,16 @@ class OrderItemRequest with _$OrderItemRequest {
     unitPrice: 0,
     notes: '',
   );
+
+  /// Bentuk baris dari isi keranjang: produk timbangan selalu `quantity: 1`
+  /// ditambah `weight`, produk cacah tetap seperti sebelumnya.
+  factory OrderItemRequest.fromProductQuantity(ProductQuantity item) =>
+      OrderItemRequest(
+        productId: item.product.id,
+        productVariantId: item.variant?.id ?? '',
+        quantity: item.isWeighted ? 1 : item.quantity,
+        unitPrice: item.product.price.toInt(),
+        notes: item.notes,
+        weight: item.weight,
+      );
 }

lib/domain/order/order.dart

@@ -3,6 +3,7 @@ import 'package:freezed_annotation/freezed_annotation.dart';
 
 import '../../common/api/api_failure.dart';
 import '../../common/types/split_type.dart';
+import '../../common/extension/extension.dart';
 import '../product/product.dart';
 
 part 'order.freezed.dart';

lib/domain/order/order.freezed.dart

@@ -1007,6 +1007,12 @@ mixin _$OrderItem {
   String get categoryId => throw _privateConstructorUsedError;
   String get categoryName => throw _privateConstructorUsedError;
 
+  /// Angka timbangan baris ini. `null` untuk produk cacah.
+  double? get weight => throw _privateConstructorUsedError;
+  String get unitId => throw _privateConstructorUsedError;
+  String get unitName => throw _privateConstructorUsedError;
+  String get unitAbbreviation => throw _privateConstructorUsedError;
+
   /// Create a copy of OrderItem
   /// with the given fields replaced by the non-null parameter values.
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -1039,6 +1045,10 @@ abstract class $OrderItemCopyWith<$Res> {
     int paidQuantity,
     String categoryId,
     String categoryName,
+    double? weight,
+    String unitId,
+    String unitName,
+    String unitAbbreviation,
   });
 }
 
@@ -1076,6 +1086,10 @@ class _$OrderItemCopyWithImpl<$Res, $Val extends OrderItem>
     Object? paidQuantity = null,
     Object? categoryId = null,
     Object? categoryName = null,
+    Object? weight = freezed,
+    Object? unitId = null,
+    Object? unitName = null,
+    Object? unitAbbreviation = null,
   }) {
     return _then(
       _value.copyWith(
@@ -1155,6 +1169,22 @@ class _$OrderItemCopyWithImpl<$Res, $Val extends OrderItem>
                 ? _value.categoryName
                 : categoryName // ignore: cast_nullable_to_non_nullable
                       as String,
+            weight: freezed == weight
+                ? _value.weight
+                : weight // ignore: cast_nullable_to_non_nullable
+                      as double?,
+            unitId: null == unitId
+                ? _value.unitId
+                : unitId // ignore: cast_nullable_to_non_nullable
+                      as String,
+            unitName: null == unitName
+                ? _value.unitName
+                : unitName // ignore: cast_nullable_to_non_nullable
+                      as String,
+            unitAbbreviation: null == unitAbbreviation
+                ? _value.unitAbbreviation
+                : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                      as String,
           )
           as $Val,
     );
@@ -1190,6 +1220,10 @@ abstract class _$$OrderItemImplCopyWith<$Res>
     int paidQuantity,
     String categoryId,
     String categoryName,
+    double? weight,
+    String unitId,
+    String unitName,
+    String unitAbbreviation,
   });
 }
 
@@ -1226,6 +1260,10 @@ class __$$OrderItemImplCopyWithImpl<$Res>
     Object? paidQuantity = null,
     Object? categoryId = null,
     Object? categoryName = null,
+    Object? weight = freezed,
+    Object? unitId = null,
+    Object? unitName = null,
+    Object? unitAbbreviation = null,
   }) {
     return _then(
       _$OrderItemImpl(
@@ -1305,6 +1343,22 @@ class __$$OrderItemImplCopyWithImpl<$Res>
             ? _value.categoryName
             : categoryName // ignore: cast_nullable_to_non_nullable
                   as String,
+        weight: freezed == weight
+            ? _value.weight
+            : weight // ignore: cast_nullable_to_non_nullable
+                  as double?,
+        unitId: null == unitId
+            ? _value.unitId
+            : unitId // ignore: cast_nullable_to_non_nullable
+                  as String,
+        unitName: null == unitName
+            ? _value.unitName
+            : unitName // ignore: cast_nullable_to_non_nullable
+                  as String,
+        unitAbbreviation: null == unitAbbreviation
+            ? _value.unitAbbreviation
+            : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                  as String,
       ),
     );
   }
@@ -1312,7 +1366,7 @@ class __$$OrderItemImplCopyWithImpl<$Res>
 
 /// @nodoc
 
-class _$OrderItemImpl implements _OrderItem {
+class _$OrderItemImpl extends _OrderItem {
   const _$OrderItemImpl({
     required this.id,
     required this.orderId,
@@ -1333,7 +1387,12 @@ class _$OrderItemImpl implements _OrderItem {
     required this.paidQuantity,
     required this.categoryId,
     required this.categoryName,
-  }) : _modifiers = modifiers;
+    this.weight,
+    this.unitId = '',
+    this.unitName = '',
+    this.unitAbbreviation = '',
+  }) : _modifiers = modifiers,
+       super._();
 
   @override
   final String id;
@@ -1380,9 +1439,22 @@ class _$OrderItemImpl implements _OrderItem {
   @override
   final String categoryName;
 
+  /// Angka timbangan baris ini. `null` untuk produk cacah.
+  @override
+  final double? weight;
+  @override
+  @JsonKey()
+  final String unitId;
+  @override
+  @JsonKey()
+  final String unitName;
+  @override
+  @JsonKey()
+  final String unitAbbreviation;
+
   @override
   String toString() {
-    return 'OrderItem(id: $id, orderId: $orderId, productId: $productId, productName: $productName, productVariantId: $productVariantId, productVariantName: $productVariantName, quantity: $quantity, unitPrice: $unitPrice, totalPrice: $totalPrice, modifiers: $modifiers, notes: $notes, status: $status, createdAt: $createdAt, updatedAt: $updatedAt, printerType: $printerType, printToChecker: $printToChecker, paidQuantity: $paidQuantity, categoryId: $categoryId, categoryName: $categoryName)';
+    return 'OrderItem(id: $id, orderId: $orderId, productId: $productId, productName: $productName, productVariantId: $productVariantId, productVariantName: $productVariantName, quantity: $quantity, unitPrice: $unitPrice, totalPrice: $totalPrice, modifiers: $modifiers, notes: $notes, status: $status, createdAt: $createdAt, updatedAt: $updatedAt, printerType: $printerType, printToChecker: $printToChecker, paidQuantity: $paidQuantity, categoryId: $categoryId, categoryName: $categoryName, weight: $weight, unitId: $unitId, unitName: $unitName, unitAbbreviation: $unitAbbreviation)';
   }
 
   @override
@@ -1425,7 +1497,13 @@ class _$OrderItemImpl implements _OrderItem {
             (identical(other.categoryId, categoryId) ||
                 other.categoryId == categoryId) &&
             (identical(other.categoryName, categoryName) ||
-                other.categoryName == categoryName));
+                other.categoryName == categoryName) &&
+            (identical(other.weight, weight) || other.weight == weight) &&
+            (identical(other.unitId, unitId) || other.unitId == unitId) &&
+            (identical(other.unitName, unitName) ||
+                other.unitName == unitName) &&
+            (identical(other.unitAbbreviation, unitAbbreviation) ||
+                other.unitAbbreviation == unitAbbreviation));
   }
 
   @override
@@ -1450,6 +1528,10 @@ class _$OrderItemImpl implements _OrderItem {
     paidQuantity,
     categoryId,
     categoryName,
+    weight,
+    unitId,
+    unitName,
+    unitAbbreviation,
   ]);
 
   /// Create a copy of OrderItem
@@ -1461,7 +1543,7 @@ class _$OrderItemImpl implements _OrderItem {
       __$$OrderItemImplCopyWithImpl<_$OrderItemImpl>(this, _$identity);
 }
 
-abstract class _OrderItem implements OrderItem {
+abstract class _OrderItem extends OrderItem {
   const factory _OrderItem({
     required final String id,
     required final String orderId,
@@ -1482,7 +1564,12 @@ abstract class _OrderItem implements OrderItem {
     required final int paidQuantity,
     required final String categoryId,
     required final String categoryName,
+    final double? weight,
+    final String unitId,
+    final String unitName,
+    final String unitAbbreviation,
   }) = _$OrderItemImpl;
+  const _OrderItem._() : super._();
 
   @override
   String get id;
@@ -1523,6 +1610,16 @@ abstract class _OrderItem implements OrderItem {
   @override
   String get categoryName;
 
+  /// Angka timbangan baris ini. `null` untuk produk cacah.
+  @override
+  double? get weight;
+  @override
+  String get unitId;
+  @override
+  String get unitName;
+  @override
+  String get unitAbbreviation;
+
   /// Create a copy of OrderItem
   /// with the given fields replaced by the non-null parameter values.
   @override
@@ -1847,6 +1944,10 @@ mixin _$OrderItemRequest {
   int get unitPrice => throw _privateConstructorUsedError;
   String get notes => throw _privateConstructorUsedError;
 
+  /// Hanya diisi untuk produk `sell_by: "weight"`; produk cacah tidak boleh
+  /// mengirim berat sama sekali.
+  double? get weight => throw _privateConstructorUsedError;
+
   /// Create a copy of OrderItemRequest
   /// with the given fields replaced by the non-null parameter values.
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -1867,6 +1968,7 @@ abstract class $OrderItemRequestCopyWith<$Res> {
     int quantity,
     int unitPrice,
     String notes,
+    double? weight,
   });
 }
 
@@ -1890,6 +1992,7 @@ class _$OrderItemRequestCopyWithImpl<$Res, $Val extends OrderItemRequest>
     Object? quantity = null,
     Object? unitPrice = null,
     Object? notes = null,
+    Object? weight = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -1913,6 +2016,10 @@ class _$OrderItemRequestCopyWithImpl<$Res, $Val extends OrderItemRequest>
                 ? _value.notes
                 : notes // ignore: cast_nullable_to_non_nullable
                       as String,
+            weight: freezed == weight
+                ? _value.weight
+                : weight // ignore: cast_nullable_to_non_nullable
+                      as double?,
           )
           as $Val,
     );
@@ -1934,6 +2041,7 @@ abstract class _$$OrderItemRequestImplCopyWith<$Res>
     int quantity,
     int unitPrice,
     String notes,
+    double? weight,
   });
 }
 
@@ -1956,6 +2064,7 @@ class __$$OrderItemRequestImplCopyWithImpl<$Res>
     Object? quantity = null,
     Object? unitPrice = null,
     Object? notes = null,
+    Object? weight = freezed,
   }) {
     return _then(
       _$OrderItemRequestImpl(
@@ -1979,6 +2088,10 @@ class __$$OrderItemRequestImplCopyWithImpl<$Res>
             ? _value.notes
             : notes // ignore: cast_nullable_to_non_nullable
                   as String,
+        weight: freezed == weight
+            ? _value.weight
+            : weight // ignore: cast_nullable_to_non_nullable
+                  as double?,
       ),
     );
   }
@@ -1993,6 +2106,7 @@ class _$OrderItemRequestImpl implements _OrderItemRequest {
     required this.quantity,
     required this.unitPrice,
     required this.notes,
+    this.weight,
   });
 
   @override
@@ -2006,9 +2120,14 @@ class _$OrderItemRequestImpl implements _OrderItemRequest {
   @override
   final String notes;
 
+  /// Hanya diisi untuk produk `sell_by: "weight"`; produk cacah tidak boleh
+  /// mengirim berat sama sekali.
+  @override
+  final double? weight;
+
   @override
   String toString() {
-    return 'OrderItemRequest(productId: $productId, productVariantId: $productVariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes)';
+    return 'OrderItemRequest(productId: $productId, productVariantId: $productVariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes, weight: $weight)';
   }
 
   @override
@@ -2024,7 +2143,8 @@ class _$OrderItemRequestImpl implements _OrderItemRequest {
                 other.quantity == quantity) &&
             (identical(other.unitPrice, unitPrice) ||
                 other.unitPrice == unitPrice) &&
-            (identical(other.notes, notes) || other.notes == notes));
+            (identical(other.notes, notes) || other.notes == notes) &&
+            (identical(other.weight, weight) || other.weight == weight));
   }
 
   @override
@@ -2035,6 +2155,7 @@ class _$OrderItemRequestImpl implements _OrderItemRequest {
     quantity,
     unitPrice,
     notes,
+    weight,
   );
 
   /// Create a copy of OrderItemRequest
@@ -2056,6 +2177,7 @@ abstract class _OrderItemRequest implements OrderItemRequest {
     required final int quantity,
     required final int unitPrice,
     required final String notes,
+    final double? weight,
   }) = _$OrderItemRequestImpl;
 
   @override
@@ -2069,6 +2191,11 @@ abstract class _OrderItemRequest implements OrderItemRequest {
   @override
   String get notes;
 
+  /// Hanya diisi untuk produk `sell_by: "weight"`; produk cacah tidak boleh
+  /// mengirim berat sama sekali.
+  @override
+  double? get weight;
+
   /// Create a copy of OrderItemRequest
   /// with the given fields replaced by the non-null parameter values.
   @override
@@ -3448,6 +3575,9 @@ mixin _$AddItemOrderRequest {
   int get unitPrice => throw _privateConstructorUsedError;
   String get notes => throw _privateConstructorUsedError;
 
+  /// Hanya diisi untuk produk `sell_by: "weight"`.
+  double? get weight => throw _privateConstructorUsedError;
+
   /// Create a copy of AddItemOrderRequest
   /// with the given fields replaced by the non-null parameter values.
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -3468,6 +3598,7 @@ abstract class $AddItemOrderRequestCopyWith<$Res> {
     int quantity,
     int unitPrice,
     String notes,
+    double? weight,
   });
 }
 
@@ -3491,6 +3622,7 @@ class _$AddItemOrderRequestCopyWithImpl<$Res, $Val extends AddItemOrderRequest>
     Object? quantity = null,
     Object? unitPrice = null,
     Object? notes = null,
+    Object? weight = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -3514,6 +3646,10 @@ class _$AddItemOrderRequestCopyWithImpl<$Res, $Val extends AddItemOrderRequest>
                 ? _value.notes
                 : notes // ignore: cast_nullable_to_non_nullable
                       as String,
+            weight: freezed == weight
+                ? _value.weight
+                : weight // ignore: cast_nullable_to_non_nullable
+                      as double?,
           )
           as $Val,
     );
@@ -3535,6 +3671,7 @@ abstract class _$$AddItemOrderRequestImplCopyWith<$Res>
     int quantity,
     int unitPrice,
     String notes,
+    double? weight,
   });
 }
 
@@ -3557,6 +3694,7 @@ class __$$AddItemOrderRequestImplCopyWithImpl<$Res>
     Object? quantity = null,
     Object? unitPrice = null,
     Object? notes = null,
+    Object? weight = freezed,
   }) {
     return _then(
       _$AddItemOrderRequestImpl(
@@ -3580,6 +3718,10 @@ class __$$AddItemOrderRequestImplCopyWithImpl<$Res>
             ? _value.notes
             : notes // ignore: cast_nullable_to_non_nullable
                   as String,
+        weight: freezed == weight
+            ? _value.weight
+            : weight // ignore: cast_nullable_to_non_nullable
+                  as double?,
       ),
     );
   }
@@ -3594,6 +3736,7 @@ class _$AddItemOrderRequestImpl implements _AddItemOrderRequest {
     required this.quantity,
     required this.unitPrice,
     required this.notes,
+    this.weight,
   });
 
   @override
@@ -3607,9 +3750,13 @@ class _$AddItemOrderRequestImpl implements _AddItemOrderRequest {
   @override
   final String notes;
 
+  /// Hanya diisi untuk produk `sell_by: "weight"`.
+  @override
+  final double? weight;
+
   @override
   String toString() {
-    return 'AddItemOrderRequest(productId: $productId, productVariantId: $productVariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes)';
+    return 'AddItemOrderRequest(productId: $productId, productVariantId: $productVariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes, weight: $weight)';
   }
 
   @override
@@ -3625,7 +3772,8 @@ class _$AddItemOrderRequestImpl implements _AddItemOrderRequest {
                 other.quantity == quantity) &&
             (identical(other.unitPrice, unitPrice) ||
                 other.unitPrice == unitPrice) &&
-            (identical(other.notes, notes) || other.notes == notes));
+            (identical(other.notes, notes) || other.notes == notes) &&
+            (identical(other.weight, weight) || other.weight == weight));
   }
 
   @override
@@ -3636,6 +3784,7 @@ class _$AddItemOrderRequestImpl implements _AddItemOrderRequest {
     quantity,
     unitPrice,
     notes,
+    weight,
   );
 
   /// Create a copy of AddItemOrderRequest
@@ -3657,6 +3806,7 @@ abstract class _AddItemOrderRequest implements AddItemOrderRequest {
     required final int quantity,
     required final int unitPrice,
     required final String notes,
+    final double? weight,
   }) = _$AddItemOrderRequestImpl;
 
   @override
@@ -3670,6 +3820,10 @@ abstract class _AddItemOrderRequest implements AddItemOrderRequest {
   @override
   String get notes;
 
+  /// Hanya diisi untuk produk `sell_by: "weight"`.
+  @override
+  double? get weight;
+
   /// Create a copy of AddItemOrderRequest
   /// with the given fields replaced by the non-null parameter values.
   @override

lib/domain/product/entities/product_entity.dart

@@ -21,6 +21,8 @@ class ListProduct with _$ListProduct {
 
 @freezed
 class Product with _$Product {
+  const Product._();
+
   const factory Product({
     required String id,
     required String organizationId,
@@ -39,6 +41,11 @@ class Product with _$Product {
     required String createdAt,
     required String updatedAt,
     required List<ProductVariant> variants,
+    /// `unit` (default) atau `weight`. Lihat [SellBy].
+    @Default(SellBy.unit) String sellBy,
+    @Default('') String unitId,
+    @Default('') String unitName,
+    @Default('') String unitAbbreviation,
   }) = _Product;
 
   factory Product.empty() => const Product(
@@ -60,6 +67,18 @@ class Product with _$Product {
     updatedAt: '',
     variants: [],
   );
+
+  /// Produk yang dijual per timbangan: `quantity` selalu 1, `weight` wajib.
+  bool get isSoldByWeight => SellBy.isWeight(sellBy);
+
+  /// Singkatan satuan untuk ditampilkan — `ons`. Jatuh ke nama panjang bila
+  /// backend hanya mengirim itu.
+  String get unitLabel =>
+      unitAbbreviation.isNotEmpty ? unitAbbreviation : unitName;
+
+  /// Label harga mengikuti satuan: "Harga per ons".
+  String get priceUnitLabel =>
+      isSoldByWeight && unitLabel.isNotEmpty ? 'per $unitLabel' : '';
 }
 
 @freezed

lib/domain/product/entities/product_quantity_entity.dart

@@ -1,14 +1,53 @@
 part of '../product.dart';
 
+/// Satu baris keranjang.
+///
+/// Untuk produk timbangan, **satu penimbangan = satu baris**: dua kali menimbang
+/// Ikan Tude menghasilkan dua baris terpisah dengan [quantity] 1 dan [weight]
+/// masing-masing. Karena itu baris dibedakan lewat [lineId], bukan lewat
+/// kombinasi produk + varian.
 @freezed
 class ProductQuantity with _$ProductQuantity {
+  const ProductQuantity._();
+
   const factory ProductQuantity({
     required Product product,
     ProductVariant? variant,
     required int quantity,
     required String notes,
+    @Default('') String lineId,
+
+    /// Angka timbangan dalam satuan produk. `null` untuk produk cacah.
+    double? weight,
   }) = _ProductQuantity;
 
   factory ProductQuantity.empty() =>
       ProductQuantity(product: Product.empty(), quantity: 0, notes: '');
+
+  bool get isWeighted => weight != null;
+
+  double get unitPrice => product.price + (variant?.priceModifier ?? 0);
+
+  /// Harga baris: `weight × unit_price` untuk timbangan, `quantity × unit_price`
+  /// untuk produk cacah.
+  double get lineTotal =>
+      isWeighted ? unitPrice * weight! : unitPrice * quantity;
+
+  /// `4,2 ons` atau `2` — dipakai di kolom Qty keranjang.
+  String get quantityLabel {
+    if (!isWeighted) return quantity.toString();
+    final label = product.unitLabel;
+    final value = weight!.weightFormat;
+    return label.isEmpty ? value : '$value $label';
+  }
+}
+
+extension ProductQuantityListExt on List<ProductQuantity> {
+  /// Total keranjang: baris berbobot pakai `weight × harga`, baris cacah pakai
+  /// `quantity × harga`.
+  double get cartTotal => fold<double>(0, (sum, item) => sum + item.lineTotal);
+
+  /// Baris berbobot dihitung satu — satu penimbangan, satu barang.
+  int get cartItemCount =>
+      fold<int>(0, (sum, item) => sum + (item.isWeighted ? 1 : item.quantity));
 }

lib/domain/product/product.dart

@@ -3,6 +3,8 @@ import 'package:flutter/foundation.dart';
 import 'package:freezed_annotation/freezed_annotation.dart';
 
 import '../../common/api/api_failure.dart';
+import '../../common/extension/extension.dart';
+import '../../common/types/sell_by.dart';
 
 part 'product.freezed.dart';
 

lib/domain/product/product.freezed.dart

@@ -286,6 +286,12 @@ mixin _$Product {
   String get updatedAt => throw _privateConstructorUsedError;
   List<ProductVariant> get variants => throw _privateConstructorUsedError;
 
+  /// `unit` (default) atau `weight`. Lihat [SellBy].
+  String get sellBy => throw _privateConstructorUsedError;
+  String get unitId => throw _privateConstructorUsedError;
+  String get unitName => throw _privateConstructorUsedError;
+  String get unitAbbreviation => throw _privateConstructorUsedError;
+
   /// Create a copy of Product
   /// with the given fields replaced by the non-null parameter values.
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -315,6 +321,10 @@ abstract class $ProductCopyWith<$Res> {
     String createdAt,
     String updatedAt,
     List<ProductVariant> variants,
+    String sellBy,
+    String unitId,
+    String unitName,
+    String unitAbbreviation,
   });
 }
 
@@ -350,6 +360,10 @@ class _$ProductCopyWithImpl<$Res, $Val extends Product>
     Object? createdAt = null,
     Object? updatedAt = null,
     Object? variants = null,
+    Object? sellBy = null,
+    Object? unitId = null,
+    Object? unitName = null,
+    Object? unitAbbreviation = null,
   }) {
     return _then(
       _value.copyWith(
@@ -421,6 +435,22 @@ class _$ProductCopyWithImpl<$Res, $Val extends Product>
                 ? _value.variants
                 : variants // ignore: cast_nullable_to_non_nullable
                       as List<ProductVariant>,
+            sellBy: null == sellBy
+                ? _value.sellBy
+                : sellBy // ignore: cast_nullable_to_non_nullable
+                      as String,
+            unitId: null == unitId
+                ? _value.unitId
+                : unitId // ignore: cast_nullable_to_non_nullable
+                      as String,
+            unitName: null == unitName
+                ? _value.unitName
+                : unitName // ignore: cast_nullable_to_non_nullable
+                      as String,
+            unitAbbreviation: null == unitAbbreviation
+                ? _value.unitAbbreviation
+                : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                      as String,
           )
           as $Val,
     );
@@ -453,6 +483,10 @@ abstract class _$$ProductImplCopyWith<$Res> implements $ProductCopyWith<$Res> {
     String createdAt,
     String updatedAt,
     List<ProductVariant> variants,
+    String sellBy,
+    String unitId,
+    String unitName,
+    String unitAbbreviation,
   });
 }
 
@@ -487,6 +521,10 @@ class __$$ProductImplCopyWithImpl<$Res>
     Object? createdAt = null,
     Object? updatedAt = null,
     Object? variants = null,
+    Object? sellBy = null,
+    Object? unitId = null,
+    Object? unitName = null,
+    Object? unitAbbreviation = null,
   }) {
     return _then(
       _$ProductImpl(
@@ -558,6 +596,22 @@ class __$$ProductImplCopyWithImpl<$Res>
             ? _value._variants
             : variants // ignore: cast_nullable_to_non_nullable
                   as List<ProductVariant>,
+        sellBy: null == sellBy
+            ? _value.sellBy
+            : sellBy // ignore: cast_nullable_to_non_nullable
+                  as String,
+        unitId: null == unitId
+            ? _value.unitId
+            : unitId // ignore: cast_nullable_to_non_nullable
+                  as String,
+        unitName: null == unitName
+            ? _value.unitName
+            : unitName // ignore: cast_nullable_to_non_nullable
+                  as String,
+        unitAbbreviation: null == unitAbbreviation
+            ? _value.unitAbbreviation
+            : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                  as String,
       ),
     );
   }
@@ -565,7 +619,7 @@ class __$$ProductImplCopyWithImpl<$Res>
 
 /// @nodoc
 
-class _$ProductImpl with DiagnosticableTreeMixin implements _Product {
+class _$ProductImpl extends _Product with DiagnosticableTreeMixin {
   const _$ProductImpl({
     required this.id,
     required this.organizationId,
@@ -584,8 +638,13 @@ class _$ProductImpl with DiagnosticableTreeMixin implements _Product {
     required this.createdAt,
     required this.updatedAt,
     required final List<ProductVariant> variants,
+    this.sellBy = SellBy.unit,
+    this.unitId = '',
+    this.unitName = '',
+    this.unitAbbreviation = '',
   }) : _metadata = metadata,
-       _variants = variants;
+       _variants = variants,
+       super._();
 
   @override
   final String id;
@@ -633,9 +692,23 @@ class _$ProductImpl with DiagnosticableTreeMixin implements _Product {
     return EqualUnmodifiableListView(_variants);
   }
 
+  /// `unit` (default) atau `weight`. Lihat [SellBy].
+  @override
+  @JsonKey()
+  final String sellBy;
+  @override
+  @JsonKey()
+  final String unitId;
+  @override
+  @JsonKey()
+  final String unitName;
+  @override
+  @JsonKey()
+  final String unitAbbreviation;
+
   @override
   String toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) {
-    return 'Product(id: $id, organizationId: $organizationId, categoryId: $categoryId, sku: $sku, name: $name, description: $description, price: $price, cost: $cost, businessType: $businessType, imageUrl: $imageUrl, printerType: $printerType, printToChecker: $printToChecker, metadata: $metadata, isActive: $isActive, createdAt: $createdAt, updatedAt: $updatedAt, variants: $variants)';
+    return 'Product(id: $id, organizationId: $organizationId, categoryId: $categoryId, sku: $sku, name: $name, description: $description, price: $price, cost: $cost, businessType: $businessType, imageUrl: $imageUrl, printerType: $printerType, printToChecker: $printToChecker, metadata: $metadata, isActive: $isActive, createdAt: $createdAt, updatedAt: $updatedAt, variants: $variants, sellBy: $sellBy, unitId: $unitId, unitName: $unitName, unitAbbreviation: $unitAbbreviation)';
   }
 
   @override
@@ -659,7 +732,11 @@ class _$ProductImpl with DiagnosticableTreeMixin implements _Product {
       ..add(DiagnosticsProperty('isActive', isActive))
       ..add(DiagnosticsProperty('createdAt', createdAt))
       ..add(DiagnosticsProperty('updatedAt', updatedAt))
-      ..add(DiagnosticsProperty('variants', variants));
+      ..add(DiagnosticsProperty('variants', variants))
+      ..add(DiagnosticsProperty('sellBy', sellBy))
+      ..add(DiagnosticsProperty('unitId', unitId))
+      ..add(DiagnosticsProperty('unitName', unitName))
+      ..add(DiagnosticsProperty('unitAbbreviation', unitAbbreviation));
   }
 
   @override
@@ -693,11 +770,17 @@ class _$ProductImpl with DiagnosticableTreeMixin implements _Product {
                 other.createdAt == createdAt) &&
             (identical(other.updatedAt, updatedAt) ||
                 other.updatedAt == updatedAt) &&
-            const DeepCollectionEquality().equals(other._variants, _variants));
+            const DeepCollectionEquality().equals(other._variants, _variants) &&
+            (identical(other.sellBy, sellBy) || other.sellBy == sellBy) &&
+            (identical(other.unitId, unitId) || other.unitId == unitId) &&
+            (identical(other.unitName, unitName) ||
+                other.unitName == unitName) &&
+            (identical(other.unitAbbreviation, unitAbbreviation) ||
+                other.unitAbbreviation == unitAbbreviation));
   }
 
   @override
-  int get hashCode => Object.hash(
+  int get hashCode => Object.hashAll([
     runtimeType,
     id,
     organizationId,
@@ -716,7 +799,11 @@ class _$ProductImpl with DiagnosticableTreeMixin implements _Product {
     createdAt,
     updatedAt,
     const DeepCollectionEquality().hash(_variants),
-  );
+    sellBy,
+    unitId,
+    unitName,
+    unitAbbreviation,
+  ]);
 
   /// Create a copy of Product
   /// with the given fields replaced by the non-null parameter values.
@@ -727,7 +814,7 @@ class _$ProductImpl with DiagnosticableTreeMixin implements _Product {
       __$$ProductImplCopyWithImpl<_$ProductImpl>(this, _$identity);
 }
 
-abstract class _Product implements Product {
+abstract class _Product extends Product {
   const factory _Product({
     required final String id,
     required final String organizationId,
@@ -746,7 +833,12 @@ abstract class _Product implements Product {
     required final String createdAt,
     required final String updatedAt,
     required final List<ProductVariant> variants,
+    final String sellBy,
+    final String unitId,
+    final String unitName,
+    final String unitAbbreviation,
   }) = _$ProductImpl;
+  const _Product._() : super._();
 
   @override
   String get id;
@@ -783,6 +875,16 @@ abstract class _Product implements Product {
   @override
   List<ProductVariant> get variants;
 
+  /// `unit` (default) atau `weight`. Lihat [SellBy].
+  @override
+  String get sellBy;
+  @override
+  String get unitId;
+  @override
+  String get unitName;
+  @override
+  String get unitAbbreviation;
+
   /// Create a copy of Product
   /// with the given fields replaced by the non-null parameter values.
   @override
@@ -1121,6 +1223,10 @@ mixin _$ProductQuantity {
   ProductVariant? get variant => throw _privateConstructorUsedError;
   int get quantity => throw _privateConstructorUsedError;
   String get notes => throw _privateConstructorUsedError;
+  String get lineId => throw _privateConstructorUsedError;
+
+  /// Angka timbangan dalam satuan produk. `null` untuk produk cacah.
+  double? get weight => throw _privateConstructorUsedError;
 
   /// Create a copy of ProductQuantity
   /// with the given fields replaced by the non-null parameter values.
@@ -1141,6 +1247,8 @@ abstract class $ProductQuantityCopyWith<$Res> {
     ProductVariant? variant,
     int quantity,
     String notes,
+    String lineId,
+    double? weight,
   });
 
   $ProductCopyWith<$Res> get product;
@@ -1166,6 +1274,8 @@ class _$ProductQuantityCopyWithImpl<$Res, $Val extends ProductQuantity>
     Object? variant = freezed,
     Object? quantity = null,
     Object? notes = null,
+    Object? lineId = null,
+    Object? weight = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -1185,6 +1295,14 @@ class _$ProductQuantityCopyWithImpl<$Res, $Val extends ProductQuantity>
                 ? _value.notes
                 : notes // ignore: cast_nullable_to_non_nullable
                       as String,
+            lineId: null == lineId
+                ? _value.lineId
+                : lineId // ignore: cast_nullable_to_non_nullable
+                      as String,
+            weight: freezed == weight
+                ? _value.weight
+                : weight // ignore: cast_nullable_to_non_nullable
+                      as double?,
           )
           as $Val,
     );
@@ -1229,6 +1347,8 @@ abstract class _$$ProductQuantityImplCopyWith<$Res>
     ProductVariant? variant,
     int quantity,
     String notes,
+    String lineId,
+    double? weight,
   });
 
   @override
@@ -1255,6 +1375,8 @@ class __$$ProductQuantityImplCopyWithImpl<$Res>
     Object? variant = freezed,
     Object? quantity = null,
     Object? notes = null,
+    Object? lineId = null,
+    Object? weight = freezed,
   }) {
     return _then(
       _$ProductQuantityImpl(
@@ -1274,6 +1396,14 @@ class __$$ProductQuantityImplCopyWithImpl<$Res>
             ? _value.notes
             : notes // ignore: cast_nullable_to_non_nullable
                   as String,
+        lineId: null == lineId
+            ? _value.lineId
+            : lineId // ignore: cast_nullable_to_non_nullable
+                  as String,
+        weight: freezed == weight
+            ? _value.weight
+            : weight // ignore: cast_nullable_to_non_nullable
+                  as double?,
       ),
     );
   }
@@ -1281,15 +1411,16 @@ class __$$ProductQuantityImplCopyWithImpl<$Res>
 
 /// @nodoc
 
-class _$ProductQuantityImpl
-    with DiagnosticableTreeMixin
-    implements _ProductQuantity {
+class _$ProductQuantityImpl extends _ProductQuantity
+    with DiagnosticableTreeMixin {
   const _$ProductQuantityImpl({
     required this.product,
     this.variant,
     required this.quantity,
     required this.notes,
-  });
+    this.lineId = '',
+    this.weight,
+  }) : super._();
 
   @override
   final Product product;
@@ -1299,10 +1430,17 @@ class _$ProductQuantityImpl
   final int quantity;
   @override
   final String notes;
+  @override
+  @JsonKey()
+  final String lineId;
+
+  /// Angka timbangan dalam satuan produk. `null` untuk produk cacah.
+  @override
+  final double? weight;
 
   @override
   String toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) {
-    return 'ProductQuantity(product: $product, variant: $variant, quantity: $quantity, notes: $notes)';
+    return 'ProductQuantity(product: $product, variant: $variant, quantity: $quantity, notes: $notes, lineId: $lineId, weight: $weight)';
   }
 
   @override
@@ -1313,7 +1451,9 @@ class _$ProductQuantityImpl
       ..add(DiagnosticsProperty('product', product))
       ..add(DiagnosticsProperty('variant', variant))
       ..add(DiagnosticsProperty('quantity', quantity))
-      ..add(DiagnosticsProperty('notes', notes));
+      ..add(DiagnosticsProperty('notes', notes))
+      ..add(DiagnosticsProperty('lineId', lineId))
+      ..add(DiagnosticsProperty('weight', weight));
   }
 
   @override
@@ -1325,12 +1465,21 @@ class _$ProductQuantityImpl
             (identical(other.variant, variant) || other.variant == variant) &&
             (identical(other.quantity, quantity) ||
                 other.quantity == quantity) &&
-            (identical(other.notes, notes) || other.notes == notes));
+            (identical(other.notes, notes) || other.notes == notes) &&
+            (identical(other.lineId, lineId) || other.lineId == lineId) &&
+            (identical(other.weight, weight) || other.weight == weight));
   }
 
   @override
-  int get hashCode =>
-      Object.hash(runtimeType, product, variant, quantity, notes);
+  int get hashCode => Object.hash(
+    runtimeType,
+    product,
+    variant,
+    quantity,
+    notes,
+    lineId,
+    weight,
+  );
 
   /// Create a copy of ProductQuantity
   /// with the given fields replaced by the non-null parameter values.
@@ -1344,13 +1493,16 @@ class _$ProductQuantityImpl
       );
 }
 
-abstract class _ProductQuantity implements ProductQuantity {
+abstract class _ProductQuantity extends ProductQuantity {
   const factory _ProductQuantity({
     required final Product product,
     final ProductVariant? variant,
     required final int quantity,
     required final String notes,
+    final String lineId,
+    final double? weight,
   }) = _$ProductQuantityImpl;
+  const _ProductQuantity._() : super._();
 
   @override
   Product get product;
@@ -1360,6 +1512,12 @@ abstract class _ProductQuantity implements ProductQuantity {
   int get quantity;
   @override
   String get notes;
+  @override
+  String get lineId;
+
+  /// Angka timbangan dalam satuan produk. `null` untuk produk cacah.
+  @override
+  double? get weight;
 
   /// Create a copy of ProductQuantity
   /// with the given fields replaced by the non-null parameter values.

lib/domain/unit/entities/unit_entity.dart

@@ -0,0 +1,23 @@
+part of '../unit.dart';
+
+/// Satuan timbangan milik organisasi — ons, kg, gram.
+///
+/// [abbreviation] yang dipakai POS untuk mencetak `4,2 ons` di struk.
+@freezed
+class ProductUnit with _$ProductUnit {
+  const factory ProductUnit({
+    required String id,
+    required String organizationId,
+    required String name,
+    required String abbreviation,
+    required bool isActive,
+  }) = _ProductUnit;
+
+  factory ProductUnit.empty() => const ProductUnit(
+    id: '',
+    organizationId: '',
+    name: '',
+    abbreviation: '',
+    isActive: false,
+  );
+}

lib/domain/unit/failures/unit_failure.dart

@@ -0,0 +1,12 @@
+part of '../unit.dart';
+
+@freezed
+sealed class UnitFailure with _$UnitFailure {
+  const factory UnitFailure.serverError(ApiFailure failure) = _ServerError;
+  const factory UnitFailure.unexpectedError() = _UnexpectedError;
+  const factory UnitFailure.empty() = _Empty;
+  const factory UnitFailure.localStorageError(String erroMessage) =
+      _LocalStorageError;
+  const factory UnitFailure.dynamicErrorMessage(String erroMessage) =
+      _DynamicErrorMessage;
+}

lib/domain/unit/repositories/i_unit_repository.dart

@@ -0,0 +1,12 @@
+part of '../unit.dart';
+
+abstract class IUnitRepository {
+  /// Ambil satuan dari server lalu simpan ke cache lokal.
+  /// Bila server tidak terjangkau, kembalikan isi cache supaya POS tetap bisa
+  /// mencetak `4,2 ons` saat offline.
+  Future<Either<UnitFailure, List<ProductUnit>>> getUnits({
+    bool forceRefresh = false,
+  });
+
+  Future<List<ProductUnit>> cachedUnits();
+}

lib/domain/unit/unit.dart

@@ -0,0 +1,10 @@
+import 'package:dartz/dartz.dart';
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+import '../../common/api/api_failure.dart';
+
+part 'unit.freezed.dart';
+
+part 'entities/unit_entity.dart';
+part 'failures/unit_failure.dart';
+part 'repositories/i_unit_repository.dart';

lib/infrastructure/order/datasources/remote_data_provider.dart

@@ -55,6 +55,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 
@@ -77,6 +83,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 
@@ -102,6 +114,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 
@@ -128,6 +146,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       } else {
         final order = OrderDto.fromJson(
@@ -171,6 +195,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 
@@ -201,6 +231,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 
@@ -239,6 +275,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 
@@ -262,6 +304,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 
@@ -290,6 +338,12 @@ class OrderRemoteDataProvider {
       );
 
       if (response.data['success'] == false) {
+        // Pesan validasi backend menyebut nama produk, jadi diteruskan apa
+        // adanya ke kasir alih-alih diganti pesan generik.
+        final cause = extractApiErrorCause(response.data);
+        if (cause != null) {
+          return DC.error(OrderFailure.dynamicErrorMessage(cause));
+        }
         return DC.error(const OrderFailure.unexpectedError());
       }
 

lib/infrastructure/order/dtos/add_item_order_request_dto.dart

@@ -10,6 +10,7 @@ class AddItemOrderRequestDto with _$AddItemOrderRequestDto {
     @JsonKey(name: 'quantity') int? quantity,
     @JsonKey(name: 'unit_price') int? unitPrice,
     @JsonKey(name: 'notes') String? notes,
+    @JsonKey(name: 'weight') double? weight,
   }) = _AddItemOrderRequestDto;
 
   factory AddItemOrderRequestDto.fromJson(Map<String, dynamic> json) =>
@@ -21,6 +22,7 @@ class AddItemOrderRequestDto with _$AddItemOrderRequestDto {
     quantity: quantity ?? 0,
     unitPrice: unitPrice ?? 0,
     notes: notes ?? '',
+    weight: weight,
   );
 
   factory AddItemOrderRequestDto.fromDomain(
@@ -31,6 +33,7 @@ class AddItemOrderRequestDto with _$AddItemOrderRequestDto {
     quantity: addItemOrderRequest.quantity,
     unitPrice: addItemOrderRequest.unitPrice,
     notes: addItemOrderRequest.notes,
+    weight: addItemOrderRequest.weight,
   );
 
   Map<String, dynamic> toRequest() {
@@ -45,6 +48,11 @@ class AddItemOrderRequestDto with _$AddItemOrderRequestDto {
       data['product_variant_id'] = productvariantId;
     }
 
+    // Produk satuan ditolak backend bila membawa berat.
+    if (weight != null) {
+      data['weight'] = weight;
+    }
+
     return data;
   }
 }

lib/infrastructure/order/dtos/order_dto.dart

@@ -118,6 +118,10 @@ class OrderItemDto with _$OrderItemDto {
     @JsonKey(name: "paid_quantity") int? paidQuantity,
     @JsonKey(name: "category_id") String? categoryId,
     @JsonKey(name: "category_name") String? categoryName,
+    @JsonKey(name: "weight") double? weight,
+    @JsonKey(name: "unit_id") String? unitId,
+    @JsonKey(name: "unit_name") String? unitName,
+    @JsonKey(name: "unit_abbreviation") String? unitAbbreviation,
   }) = _OrderItemDto;
 
   factory OrderItemDto.fromJson(Map<String, dynamic> json) =>
@@ -144,6 +148,10 @@ class OrderItemDto with _$OrderItemDto {
     paidQuantity: paidQuantity ?? 0,
     categoryId: categoryId ?? '',
     categoryName: categoryName ?? '',
+    weight: weight,
+    unitId: unitId ?? '',
+    unitName: unitName ?? '',
+    unitAbbreviation: unitAbbreviation ?? '',
   );
 
   factory OrderItemDto.fromDomain(OrderItem orderItem) => OrderItemDto(
@@ -166,5 +174,9 @@ class OrderItemDto with _$OrderItemDto {
     paidQuantity: orderItem.paidQuantity,
     categoryId: orderItem.categoryId,
     categoryName: orderItem.categoryName,
+    weight: orderItem.weight,
+    unitId: orderItem.unitId,
+    unitName: orderItem.unitName,
+    unitAbbreviation: orderItem.unitAbbreviation,
   );
 }

lib/infrastructure/order/dtos/order_request_dto.dart

@@ -75,6 +75,7 @@ class OrderItemRequestDto with _$OrderItemRequestDto {
     @JsonKey(name: "quantity") int? quantity,
     @JsonKey(name: "unit_price") int? unitPrice,
     @JsonKey(name: "notes") String? notes,
+    @JsonKey(name: "weight") double? weight,
   }) = _OrderItemRequestDto;
 
   factory OrderItemRequestDto.fromJson(Map<String, dynamic> json) =>
@@ -87,6 +88,7 @@ class OrderItemRequestDto with _$OrderItemRequestDto {
     quantity: quantity ?? 0,
     unitPrice: unitPrice ?? 0,
     notes: notes ?? '',
+    weight: weight,
   );
 
   factory OrderItemRequestDto.fromDomain(OrderItemRequest request) =>
@@ -96,6 +98,7 @@ class OrderItemRequestDto with _$OrderItemRequestDto {
         quantity: request.quantity,
         unitPrice: request.unitPrice,
         notes: request.notes,
+        weight: request.weight,
       );
 
   Map<String, dynamic> toRequest() {
@@ -110,6 +113,12 @@ class OrderItemRequestDto with _$OrderItemRequestDto {
       data["product_variant_id"] = productVariantId;
     }
 
+    // Produk satuan ditolak backend bila membawa berat, jadi field ini hanya
+    // ikut saat memang ada hasil timbangan.
+    if (weight != null) {
+      data["weight"] = weight;
+    }
+
     return data;
   }
 }

lib/infrastructure/order/order_dtos.freezed.dart

@@ -1177,6 +1177,14 @@ mixin _$OrderItemDto {
   String? get categoryId => throw _privateConstructorUsedError;
   @JsonKey(name: "category_name")
   String? get categoryName => throw _privateConstructorUsedError;
+  @JsonKey(name: "weight")
+  double? get weight => throw _privateConstructorUsedError;
+  @JsonKey(name: "unit_id")
+  String? get unitId => throw _privateConstructorUsedError;
+  @JsonKey(name: "unit_name")
+  String? get unitName => throw _privateConstructorUsedError;
+  @JsonKey(name: "unit_abbreviation")
+  String? get unitAbbreviation => throw _privateConstructorUsedError;
 
   /// Serializes this OrderItemDto to a JSON map.
   Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
@@ -1215,6 +1223,10 @@ abstract class $OrderItemDtoCopyWith<$Res> {
     @JsonKey(name: "paid_quantity") int? paidQuantity,
     @JsonKey(name: "category_id") String? categoryId,
     @JsonKey(name: "category_name") String? categoryName,
+    @JsonKey(name: "weight") double? weight,
+    @JsonKey(name: "unit_id") String? unitId,
+    @JsonKey(name: "unit_name") String? unitName,
+    @JsonKey(name: "unit_abbreviation") String? unitAbbreviation,
   });
 }
 
@@ -1252,6 +1264,10 @@ class _$OrderItemDtoCopyWithImpl<$Res, $Val extends OrderItemDto>
     Object? paidQuantity = freezed,
     Object? categoryId = freezed,
     Object? categoryName = freezed,
+    Object? weight = freezed,
+    Object? unitId = freezed,
+    Object? unitName = freezed,
+    Object? unitAbbreviation = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -1331,6 +1347,22 @@ class _$OrderItemDtoCopyWithImpl<$Res, $Val extends OrderItemDto>
                 ? _value.categoryName
                 : categoryName // ignore: cast_nullable_to_non_nullable
                       as String?,
+            weight: freezed == weight
+                ? _value.weight
+                : weight // ignore: cast_nullable_to_non_nullable
+                      as double?,
+            unitId: freezed == unitId
+                ? _value.unitId
+                : unitId // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            unitName: freezed == unitName
+                ? _value.unitName
+                : unitName // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            unitAbbreviation: freezed == unitAbbreviation
+                ? _value.unitAbbreviation
+                : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                      as String?,
           )
           as $Val,
     );
@@ -1366,6 +1398,10 @@ abstract class _$$OrderItemDtoImplCopyWith<$Res>
     @JsonKey(name: "paid_quantity") int? paidQuantity,
     @JsonKey(name: "category_id") String? categoryId,
     @JsonKey(name: "category_name") String? categoryName,
+    @JsonKey(name: "weight") double? weight,
+    @JsonKey(name: "unit_id") String? unitId,
+    @JsonKey(name: "unit_name") String? unitName,
+    @JsonKey(name: "unit_abbreviation") String? unitAbbreviation,
   });
 }
 
@@ -1402,6 +1438,10 @@ class __$$OrderItemDtoImplCopyWithImpl<$Res>
     Object? paidQuantity = freezed,
     Object? categoryId = freezed,
     Object? categoryName = freezed,
+    Object? weight = freezed,
+    Object? unitId = freezed,
+    Object? unitName = freezed,
+    Object? unitAbbreviation = freezed,
   }) {
     return _then(
       _$OrderItemDtoImpl(
@@ -1481,6 +1521,22 @@ class __$$OrderItemDtoImplCopyWithImpl<$Res>
             ? _value.categoryName
             : categoryName // ignore: cast_nullable_to_non_nullable
                   as String?,
+        weight: freezed == weight
+            ? _value.weight
+            : weight // ignore: cast_nullable_to_non_nullable
+                  as double?,
+        unitId: freezed == unitId
+            ? _value.unitId
+            : unitId // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        unitName: freezed == unitName
+            ? _value.unitName
+            : unitName // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        unitAbbreviation: freezed == unitAbbreviation
+            ? _value.unitAbbreviation
+            : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                  as String?,
       ),
     );
   }
@@ -1509,6 +1565,10 @@ class _$OrderItemDtoImpl extends _OrderItemDto {
     @JsonKey(name: "paid_quantity") this.paidQuantity,
     @JsonKey(name: "category_id") this.categoryId,
     @JsonKey(name: "category_name") this.categoryName,
+    @JsonKey(name: "weight") this.weight,
+    @JsonKey(name: "unit_id") this.unitId,
+    @JsonKey(name: "unit_name") this.unitName,
+    @JsonKey(name: "unit_abbreviation") this.unitAbbreviation,
   }) : _modifiers = modifiers,
        super._();
 
@@ -1580,10 +1640,22 @@ class _$OrderItemDtoImpl extends _OrderItemDto {
   @override
   @JsonKey(name: "category_name")
   final String? categoryName;
+  @override
+  @JsonKey(name: "weight")
+  final double? weight;
+  @override
+  @JsonKey(name: "unit_id")
+  final String? unitId;
+  @override
+  @JsonKey(name: "unit_name")
+  final String? unitName;
+  @override
+  @JsonKey(name: "unit_abbreviation")
+  final String? unitAbbreviation;
 
   @override
   String toString() {
-    return 'OrderItemDto(id: $id, orderId: $orderId, productId: $productId, productName: $productName, productVariantId: $productVariantId, productVariantName: $productVariantName, quantity: $quantity, unitPrice: $unitPrice, totalPrice: $totalPrice, modifiers: $modifiers, notes: $notes, status: $status, createdAt: $createdAt, updatedAt: $updatedAt, printerType: $printerType, printToChecker: $printToChecker, paidQuantity: $paidQuantity, categoryId: $categoryId, categoryName: $categoryName)';
+    return 'OrderItemDto(id: $id, orderId: $orderId, productId: $productId, productName: $productName, productVariantId: $productVariantId, productVariantName: $productVariantName, quantity: $quantity, unitPrice: $unitPrice, totalPrice: $totalPrice, modifiers: $modifiers, notes: $notes, status: $status, createdAt: $createdAt, updatedAt: $updatedAt, printerType: $printerType, printToChecker: $printToChecker, paidQuantity: $paidQuantity, categoryId: $categoryId, categoryName: $categoryName, weight: $weight, unitId: $unitId, unitName: $unitName, unitAbbreviation: $unitAbbreviation)';
   }
 
   @override
@@ -1626,7 +1698,13 @@ class _$OrderItemDtoImpl extends _OrderItemDto {
             (identical(other.categoryId, categoryId) ||
                 other.categoryId == categoryId) &&
             (identical(other.categoryName, categoryName) ||
-                other.categoryName == categoryName));
+                other.categoryName == categoryName) &&
+            (identical(other.weight, weight) || other.weight == weight) &&
+            (identical(other.unitId, unitId) || other.unitId == unitId) &&
+            (identical(other.unitName, unitName) ||
+                other.unitName == unitName) &&
+            (identical(other.unitAbbreviation, unitAbbreviation) ||
+                other.unitAbbreviation == unitAbbreviation));
   }
 
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -1652,6 +1730,10 @@ class _$OrderItemDtoImpl extends _OrderItemDto {
     paidQuantity,
     categoryId,
     categoryName,
+    weight,
+    unitId,
+    unitName,
+    unitAbbreviation,
   ]);
 
   /// Create a copy of OrderItemDto
@@ -1689,6 +1771,10 @@ abstract class _OrderItemDto extends OrderItemDto {
     @JsonKey(name: "paid_quantity") final int? paidQuantity,
     @JsonKey(name: "category_id") final String? categoryId,
     @JsonKey(name: "category_name") final String? categoryName,
+    @JsonKey(name: "weight") final double? weight,
+    @JsonKey(name: "unit_id") final String? unitId,
+    @JsonKey(name: "unit_name") final String? unitName,
+    @JsonKey(name: "unit_abbreviation") final String? unitAbbreviation,
   }) = _$OrderItemDtoImpl;
   const _OrderItemDto._() : super._();
 
@@ -1752,6 +1838,18 @@ abstract class _OrderItemDto extends OrderItemDto {
   @override
   @JsonKey(name: "category_name")
   String? get categoryName;
+  @override
+  @JsonKey(name: "weight")
+  double? get weight;
+  @override
+  @JsonKey(name: "unit_id")
+  String? get unitId;
+  @override
+  @JsonKey(name: "unit_name")
+  String? get unitName;
+  @override
+  @JsonKey(name: "unit_abbreviation")
+  String? get unitAbbreviation;
 
   /// Create a copy of OrderItemDto
   /// with the given fields replaced by the non-null parameter values.
@@ -2136,6 +2234,8 @@ mixin _$OrderItemRequestDto {
   int? get unitPrice => throw _privateConstructorUsedError;
   @JsonKey(name: "notes")
   String? get notes => throw _privateConstructorUsedError;
+  @JsonKey(name: "weight")
+  double? get weight => throw _privateConstructorUsedError;
 
   /// Serializes this OrderItemRequestDto to a JSON map.
   Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
@@ -2160,6 +2260,7 @@ abstract class $OrderItemRequestDtoCopyWith<$Res> {
     @JsonKey(name: "quantity") int? quantity,
     @JsonKey(name: "unit_price") int? unitPrice,
     @JsonKey(name: "notes") String? notes,
+    @JsonKey(name: "weight") double? weight,
   });
 }
 
@@ -2183,6 +2284,7 @@ class _$OrderItemRequestDtoCopyWithImpl<$Res, $Val extends OrderItemRequestDto>
     Object? quantity = freezed,
     Object? unitPrice = freezed,
     Object? notes = freezed,
+    Object? weight = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -2206,6 +2308,10 @@ class _$OrderItemRequestDtoCopyWithImpl<$Res, $Val extends OrderItemRequestDto>
                 ? _value.notes
                 : notes // ignore: cast_nullable_to_non_nullable
                       as String?,
+            weight: freezed == weight
+                ? _value.weight
+                : weight // ignore: cast_nullable_to_non_nullable
+                      as double?,
           )
           as $Val,
     );
@@ -2227,6 +2333,7 @@ abstract class _$$OrderItemRequestDtoImplCopyWith<$Res>
     @JsonKey(name: "quantity") int? quantity,
     @JsonKey(name: "unit_price") int? unitPrice,
     @JsonKey(name: "notes") String? notes,
+    @JsonKey(name: "weight") double? weight,
   });
 }
 
@@ -2249,6 +2356,7 @@ class __$$OrderItemRequestDtoImplCopyWithImpl<$Res>
     Object? quantity = freezed,
     Object? unitPrice = freezed,
     Object? notes = freezed,
+    Object? weight = freezed,
   }) {
     return _then(
       _$OrderItemRequestDtoImpl(
@@ -2272,6 +2380,10 @@ class __$$OrderItemRequestDtoImplCopyWithImpl<$Res>
             ? _value.notes
             : notes // ignore: cast_nullable_to_non_nullable
                   as String?,
+        weight: freezed == weight
+            ? _value.weight
+            : weight // ignore: cast_nullable_to_non_nullable
+                  as double?,
       ),
     );
   }
@@ -2286,6 +2398,7 @@ class _$OrderItemRequestDtoImpl extends _OrderItemRequestDto {
     @JsonKey(name: "quantity") this.quantity,
     @JsonKey(name: "unit_price") this.unitPrice,
     @JsonKey(name: "notes") this.notes,
+    @JsonKey(name: "weight") this.weight,
   }) : super._();
 
   factory _$OrderItemRequestDtoImpl.fromJson(Map<String, dynamic> json) =>
@@ -2306,10 +2419,13 @@ class _$OrderItemRequestDtoImpl extends _OrderItemRequestDto {
   @override
   @JsonKey(name: "notes")
   final String? notes;
+  @override
+  @JsonKey(name: "weight")
+  final double? weight;
 
   @override
   String toString() {
-    return 'OrderItemRequestDto(productId: $productId, productVariantId: $productVariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes)';
+    return 'OrderItemRequestDto(productId: $productId, productVariantId: $productVariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes, weight: $weight)';
   }
 
   @override
@@ -2325,7 +2441,8 @@ class _$OrderItemRequestDtoImpl extends _OrderItemRequestDto {
                 other.quantity == quantity) &&
             (identical(other.unitPrice, unitPrice) ||
                 other.unitPrice == unitPrice) &&
-            (identical(other.notes, notes) || other.notes == notes));
+            (identical(other.notes, notes) || other.notes == notes) &&
+            (identical(other.weight, weight) || other.weight == weight));
   }
 
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -2337,6 +2454,7 @@ class _$OrderItemRequestDtoImpl extends _OrderItemRequestDto {
     quantity,
     unitPrice,
     notes,
+    weight,
   );
 
   /// Create a copy of OrderItemRequestDto
@@ -2363,6 +2481,7 @@ abstract class _OrderItemRequestDto extends OrderItemRequestDto {
     @JsonKey(name: "quantity") final int? quantity,
     @JsonKey(name: "unit_price") final int? unitPrice,
     @JsonKey(name: "notes") final String? notes,
+    @JsonKey(name: "weight") final double? weight,
   }) = _$OrderItemRequestDtoImpl;
   const _OrderItemRequestDto._() : super._();
 
@@ -2384,6 +2503,9 @@ abstract class _OrderItemRequestDto extends OrderItemRequestDto {
   @override
   @JsonKey(name: "notes")
   String? get notes;
+  @override
+  @JsonKey(name: "weight")
+  double? get weight;
 
   /// Create a copy of OrderItemRequestDto
   /// with the given fields replaced by the non-null parameter values.
@@ -4025,6 +4147,8 @@ mixin _$AddItemOrderRequestDto {
   int? get unitPrice => throw _privateConstructorUsedError;
   @JsonKey(name: 'notes')
   String? get notes => throw _privateConstructorUsedError;
+  @JsonKey(name: 'weight')
+  double? get weight => throw _privateConstructorUsedError;
 
   /// Serializes this AddItemOrderRequestDto to a JSON map.
   Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
@@ -4049,6 +4173,7 @@ abstract class $AddItemOrderRequestDtoCopyWith<$Res> {
     @JsonKey(name: 'quantity') int? quantity,
     @JsonKey(name: 'unit_price') int? unitPrice,
     @JsonKey(name: 'notes') String? notes,
+    @JsonKey(name: 'weight') double? weight,
   });
 }
 
@@ -4075,6 +4200,7 @@ class _$AddItemOrderRequestDtoCopyWithImpl<
     Object? quantity = freezed,
     Object? unitPrice = freezed,
     Object? notes = freezed,
+    Object? weight = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -4098,6 +4224,10 @@ class _$AddItemOrderRequestDtoCopyWithImpl<
                 ? _value.notes
                 : notes // ignore: cast_nullable_to_non_nullable
                       as String?,
+            weight: freezed == weight
+                ? _value.weight
+                : weight // ignore: cast_nullable_to_non_nullable
+                      as double?,
           )
           as $Val,
     );
@@ -4119,6 +4249,7 @@ abstract class _$$AddItemOrderRequestDtoImplCopyWith<$Res>
     @JsonKey(name: 'quantity') int? quantity,
     @JsonKey(name: 'unit_price') int? unitPrice,
     @JsonKey(name: 'notes') String? notes,
+    @JsonKey(name: 'weight') double? weight,
   });
 }
 
@@ -4142,6 +4273,7 @@ class __$$AddItemOrderRequestDtoImplCopyWithImpl<$Res>
     Object? quantity = freezed,
     Object? unitPrice = freezed,
     Object? notes = freezed,
+    Object? weight = freezed,
   }) {
     return _then(
       _$AddItemOrderRequestDtoImpl(
@@ -4165,6 +4297,10 @@ class __$$AddItemOrderRequestDtoImplCopyWithImpl<$Res>
             ? _value.notes
             : notes // ignore: cast_nullable_to_non_nullable
                   as String?,
+        weight: freezed == weight
+            ? _value.weight
+            : weight // ignore: cast_nullable_to_non_nullable
+                  as double?,
       ),
     );
   }
@@ -4179,6 +4315,7 @@ class _$AddItemOrderRequestDtoImpl extends _AddItemOrderRequestDto {
     @JsonKey(name: 'quantity') this.quantity,
     @JsonKey(name: 'unit_price') this.unitPrice,
     @JsonKey(name: 'notes') this.notes,
+    @JsonKey(name: 'weight') this.weight,
   }) : super._();
 
   factory _$AddItemOrderRequestDtoImpl.fromJson(Map<String, dynamic> json) =>
@@ -4199,10 +4336,13 @@ class _$AddItemOrderRequestDtoImpl extends _AddItemOrderRequestDto {
   @override
   @JsonKey(name: 'notes')
   final String? notes;
+  @override
+  @JsonKey(name: 'weight')
+  final double? weight;
 
   @override
   String toString() {
-    return 'AddItemOrderRequestDto(productId: $productId, productvariantId: $productvariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes)';
+    return 'AddItemOrderRequestDto(productId: $productId, productvariantId: $productvariantId, quantity: $quantity, unitPrice: $unitPrice, notes: $notes, weight: $weight)';
   }
 
   @override
@@ -4218,7 +4358,8 @@ class _$AddItemOrderRequestDtoImpl extends _AddItemOrderRequestDto {
                 other.quantity == quantity) &&
             (identical(other.unitPrice, unitPrice) ||
                 other.unitPrice == unitPrice) &&
-            (identical(other.notes, notes) || other.notes == notes));
+            (identical(other.notes, notes) || other.notes == notes) &&
+            (identical(other.weight, weight) || other.weight == weight));
   }
 
   @JsonKey(includeFromJson: false, includeToJson: false)
@@ -4230,6 +4371,7 @@ class _$AddItemOrderRequestDtoImpl extends _AddItemOrderRequestDto {
     quantity,
     unitPrice,
     notes,
+    weight,
   );
 
   /// Create a copy of AddItemOrderRequestDto
@@ -4257,6 +4399,7 @@ abstract class _AddItemOrderRequestDto extends AddItemOrderRequestDto {
     @JsonKey(name: 'quantity') final int? quantity,
     @JsonKey(name: 'unit_price') final int? unitPrice,
     @JsonKey(name: 'notes') final String? notes,
+    @JsonKey(name: 'weight') final double? weight,
   }) = _$AddItemOrderRequestDtoImpl;
   const _AddItemOrderRequestDto._() : super._();
 
@@ -4278,6 +4421,9 @@ abstract class _AddItemOrderRequestDto extends AddItemOrderRequestDto {
   @override
   @JsonKey(name: 'notes')
   String? get notes;
+  @override
+  @JsonKey(name: 'weight')
+  double? get weight;
 
   /// Create a copy of AddItemOrderRequestDto
   /// with the given fields replaced by the non-null parameter values.

lib/infrastructure/order/order_dtos.g.dart

@@ -113,6 +113,10 @@ _$OrderItemDtoImpl _$$OrderItemDtoImplFromJson(Map<String, dynamic> json) =>
       paidQuantity: (json['paid_quantity'] as num?)?.toInt(),
       categoryId: json['category_id'] as String?,
       categoryName: json['category_name'] as String?,
+      weight: (json['weight'] as num?)?.toDouble(),
+      unitId: json['unit_id'] as String?,
+      unitName: json['unit_name'] as String?,
+      unitAbbreviation: json['unit_abbreviation'] as String?,
     );
 
 Map<String, dynamic> _$$OrderItemDtoImplToJson(_$OrderItemDtoImpl instance) =>
@@ -136,6 +140,10 @@ Map<String, dynamic> _$$OrderItemDtoImplToJson(_$OrderItemDtoImpl instance) =>
       'paid_quantity': instance.paidQuantity,
       'category_id': instance.categoryId,
       'category_name': instance.categoryName,
+      'weight': instance.weight,
+      'unit_id': instance.unitId,
+      'unit_name': instance.unitName,
+      'unit_abbreviation': instance.unitAbbreviation,
     };
 
 _$OrderRequestDtoImpl _$$OrderRequestDtoImplFromJson(
@@ -174,6 +182,7 @@ _$OrderItemRequestDtoImpl _$$OrderItemRequestDtoImplFromJson(
   quantity: (json['quantity'] as num?)?.toInt(),
   unitPrice: (json['unit_price'] as num?)?.toInt(),
   notes: json['notes'] as String?,
+  weight: (json['weight'] as num?)?.toDouble(),
 );
 
 Map<String, dynamic> _$$OrderItemRequestDtoImplToJson(
@@ -184,6 +193,7 @@ Map<String, dynamic> _$$OrderItemRequestDtoImplToJson(
   'quantity': instance.quantity,
   'unit_price': instance.unitPrice,
   'notes': instance.notes,
+  'weight': instance.weight,
 };
 
 _$PaymentRequestDtoImpl _$$PaymentRequestDtoImplFromJson(
@@ -317,6 +327,7 @@ _$AddItemOrderRequestDtoImpl _$$AddItemOrderRequestDtoImplFromJson(
   quantity: (json['quantity'] as num?)?.toInt(),
   unitPrice: (json['unit_price'] as num?)?.toInt(),
   notes: json['notes'] as String?,
+  weight: (json['weight'] as num?)?.toDouble(),
 );
 
 Map<String, dynamic> _$$AddItemOrderRequestDtoImplToJson(
@@ -327,4 +338,5 @@ Map<String, dynamic> _$$AddItemOrderRequestDtoImplToJson(
   'quantity': instance.quantity,
   'unit_price': instance.unitPrice,
   'notes': instance.notes,
+  'weight': instance.weight,
 };

lib/infrastructure/product/dtos/product_dto.dart

@@ -24,6 +24,25 @@ class ListProductDto with _$ListProductDto {
   );
 }
 
+/// Satuan yang menempel pada produk.
+///
+/// Backend hanya dijamin mengirim `unit_id`; sebagian response ikut menyertakan
+/// objek `unit` lengkap. Kalau ada, dipakai langsung supaya POS tidak perlu
+/// menunggu master satuan termuat.
+@freezed
+class ProductUnitDto with _$ProductUnitDto {
+  const ProductUnitDto._();
+
+  const factory ProductUnitDto({
+    @JsonKey(name: "id") String? id,
+    @JsonKey(name: "name") String? name,
+    @JsonKey(name: "abbreviation") String? abbreviation,
+  }) = _ProductUnitDto;
+
+  factory ProductUnitDto.fromJson(Map<String, dynamic> json) =>
+      _$ProductUnitDtoFromJson(json);
+}
+
 @freezed
 class ProductDto with _$ProductDto {
   const ProductDto._();
@@ -46,11 +65,28 @@ class ProductDto with _$ProductDto {
     @JsonKey(name: "created_at") String? createdAt,
     @JsonKey(name: "updated_at") String? updatedAt,
     @JsonKey(name: "variants") List<ProductVariantDto>? variants,
+    @JsonKey(name: "sell_by") String? sellBy,
+    @JsonKey(name: "unit_id") String? unitId,
+    @JsonKey(name: "unit_name") String? unitName,
+    @JsonKey(name: "unit_abbreviation") String? unitAbbreviation,
+    @JsonKey(name: "unit") ProductUnitDto? unit,
   }) = _ProductDto;
 
   factory ProductDto.fromJson(Map<String, dynamic> json) =>
       _$ProductDtoFromJson(json);
 
+  String get _resolvedUnitId =>
+      (unitId?.isNotEmpty == true ? unitId : unit?.id) ?? '';
+
+  String get _resolvedUnitName =>
+      (unitName?.isNotEmpty == true ? unitName : unit?.name) ?? '';
+
+  String get _resolvedUnitAbbreviation =>
+      (unitAbbreviation?.isNotEmpty == true
+          ? unitAbbreviation
+          : unit?.abbreviation) ??
+      '';
+
   /// Mapping ke domain
   Product toDomain() => Product(
     id: id ?? '',
@@ -70,6 +106,10 @@ class ProductDto with _$ProductDto {
     createdAt: createdAt ?? '',
     updatedAt: updatedAt ?? '',
     variants: variants?.map((v) => v.toDomain()).toList() ?? [],
+    sellBy: SellBy.normalize(sellBy),
+    unitId: _resolvedUnitId,
+    unitName: _resolvedUnitName,
+    unitAbbreviation: _resolvedUnitAbbreviation,
   );
 
   Map<String, dynamic> toMap() => {
@@ -89,6 +129,10 @@ class ProductDto with _$ProductDto {
     'is_active': isActive == true ? 1 : 0,
     'created_at': createdAt,
     'updated_at': updatedAt,
+    'sell_by': SellBy.normalize(sellBy),
+    'unit_id': _resolvedUnitId,
+    'unit_name': _resolvedUnitName,
+    'unit_abbreviation': _resolvedUnitAbbreviation,
   };
 
   factory ProductDto.fromMap(
@@ -117,6 +161,10 @@ class ProductDto with _$ProductDto {
     createdAt: map['created_at'] as String?,
     updatedAt: map['updated_at'] as String?,
     variants: variants,
+    sellBy: map['sell_by'] as String?,
+    unitId: map['unit_id'] as String?,
+    unitName: map['unit_name'] as String?,
+    unitAbbreviation: map['unit_abbreviation'] as String?,
   );
 
   factory ProductDto.fromDomain(Product product) => ProductDto(
@@ -139,6 +187,10 @@ class ProductDto with _$ProductDto {
     variants: product.variants
         .map((v) => ProductVariantDto.fromDomain(v))
         .toList(),
+    sellBy: product.sellBy,
+    unitId: product.unitId,
+    unitName: product.unitName,
+    unitAbbreviation: product.unitAbbreviation,
   );
 }
 

lib/infrastructure/product/product_dtos.dart

@@ -2,6 +2,7 @@ import 'dart:convert';
 
 import 'package:freezed_annotation/freezed_annotation.dart';
 
+import '../../common/types/sell_by.dart';
 import '../../domain/product/product.dart';
 
 part 'product_dtos.freezed.dart';

lib/infrastructure/product/product_dtos.freezed.dart

@@ -293,6 +293,223 @@ abstract class _ListProductDto extends ListProductDto {
       throw _privateConstructorUsedError;
 }
 
+ProductUnitDto _$ProductUnitDtoFromJson(Map<String, dynamic> json) {
+  return _ProductUnitDto.fromJson(json);
+}
+
+/// @nodoc
+mixin _$ProductUnitDto {
+  @JsonKey(name: "id")
+  String? get id => throw _privateConstructorUsedError;
+  @JsonKey(name: "name")
+  String? get name => throw _privateConstructorUsedError;
+  @JsonKey(name: "abbreviation")
+  String? get abbreviation => throw _privateConstructorUsedError;
+
+  /// Serializes this ProductUnitDto to a JSON map.
+  Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
+
+  /// Create a copy of ProductUnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  $ProductUnitDtoCopyWith<ProductUnitDto> get copyWith =>
+      throw _privateConstructorUsedError;
+}
+
+/// @nodoc
+abstract class $ProductUnitDtoCopyWith<$Res> {
+  factory $ProductUnitDtoCopyWith(
+    ProductUnitDto value,
+    $Res Function(ProductUnitDto) then,
+  ) = _$ProductUnitDtoCopyWithImpl<$Res, ProductUnitDto>;
+  @useResult
+  $Res call({
+    @JsonKey(name: "id") String? id,
+    @JsonKey(name: "name") String? name,
+    @JsonKey(name: "abbreviation") String? abbreviation,
+  });
+}
+
+/// @nodoc
+class _$ProductUnitDtoCopyWithImpl<$Res, $Val extends ProductUnitDto>
+    implements $ProductUnitDtoCopyWith<$Res> {
+  _$ProductUnitDtoCopyWithImpl(this._value, this._then);
+
+  // ignore: unused_field
+  final $Val _value;
+  // ignore: unused_field
+  final $Res Function($Val) _then;
+
+  /// Create a copy of ProductUnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? id = freezed,
+    Object? name = freezed,
+    Object? abbreviation = freezed,
+  }) {
+    return _then(
+      _value.copyWith(
+            id: freezed == id
+                ? _value.id
+                : id // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            name: freezed == name
+                ? _value.name
+                : name // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            abbreviation: freezed == abbreviation
+                ? _value.abbreviation
+                : abbreviation // ignore: cast_nullable_to_non_nullable
+                      as String?,
+          )
+          as $Val,
+    );
+  }
+}
+
+/// @nodoc
+abstract class _$$ProductUnitDtoImplCopyWith<$Res>
+    implements $ProductUnitDtoCopyWith<$Res> {
+  factory _$$ProductUnitDtoImplCopyWith(
+    _$ProductUnitDtoImpl value,
+    $Res Function(_$ProductUnitDtoImpl) then,
+  ) = __$$ProductUnitDtoImplCopyWithImpl<$Res>;
+  @override
+  @useResult
+  $Res call({
+    @JsonKey(name: "id") String? id,
+    @JsonKey(name: "name") String? name,
+    @JsonKey(name: "abbreviation") String? abbreviation,
+  });
+}
+
+/// @nodoc
+class __$$ProductUnitDtoImplCopyWithImpl<$Res>
+    extends _$ProductUnitDtoCopyWithImpl<$Res, _$ProductUnitDtoImpl>
+    implements _$$ProductUnitDtoImplCopyWith<$Res> {
+  __$$ProductUnitDtoImplCopyWithImpl(
+    _$ProductUnitDtoImpl _value,
+    $Res Function(_$ProductUnitDtoImpl) _then,
+  ) : super(_value, _then);
+
+  /// Create a copy of ProductUnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? id = freezed,
+    Object? name = freezed,
+    Object? abbreviation = freezed,
+  }) {
+    return _then(
+      _$ProductUnitDtoImpl(
+        id: freezed == id
+            ? _value.id
+            : id // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        name: freezed == name
+            ? _value.name
+            : name // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        abbreviation: freezed == abbreviation
+            ? _value.abbreviation
+            : abbreviation // ignore: cast_nullable_to_non_nullable
+                  as String?,
+      ),
+    );
+  }
+}
+
+/// @nodoc
+@JsonSerializable()
+class _$ProductUnitDtoImpl extends _ProductUnitDto {
+  const _$ProductUnitDtoImpl({
+    @JsonKey(name: "id") this.id,
+    @JsonKey(name: "name") this.name,
+    @JsonKey(name: "abbreviation") this.abbreviation,
+  }) : super._();
+
+  factory _$ProductUnitDtoImpl.fromJson(Map<String, dynamic> json) =>
+      _$$ProductUnitDtoImplFromJson(json);
+
+  @override
+  @JsonKey(name: "id")
+  final String? id;
+  @override
+  @JsonKey(name: "name")
+  final String? name;
+  @override
+  @JsonKey(name: "abbreviation")
+  final String? abbreviation;
+
+  @override
+  String toString() {
+    return 'ProductUnitDto(id: $id, name: $name, abbreviation: $abbreviation)';
+  }
+
+  @override
+  bool operator ==(Object other) {
+    return identical(this, other) ||
+        (other.runtimeType == runtimeType &&
+            other is _$ProductUnitDtoImpl &&
+            (identical(other.id, id) || other.id == id) &&
+            (identical(other.name, name) || other.name == name) &&
+            (identical(other.abbreviation, abbreviation) ||
+                other.abbreviation == abbreviation));
+  }
+
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  @override
+  int get hashCode => Object.hash(runtimeType, id, name, abbreviation);
+
+  /// Create a copy of ProductUnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  @override
+  @pragma('vm:prefer-inline')
+  _$$ProductUnitDtoImplCopyWith<_$ProductUnitDtoImpl> get copyWith =>
+      __$$ProductUnitDtoImplCopyWithImpl<_$ProductUnitDtoImpl>(
+        this,
+        _$identity,
+      );
+
+  @override
+  Map<String, dynamic> toJson() {
+    return _$$ProductUnitDtoImplToJson(this);
+  }
+}
+
+abstract class _ProductUnitDto extends ProductUnitDto {
+  const factory _ProductUnitDto({
+    @JsonKey(name: "id") final String? id,
+    @JsonKey(name: "name") final String? name,
+    @JsonKey(name: "abbreviation") final String? abbreviation,
+  }) = _$ProductUnitDtoImpl;
+  const _ProductUnitDto._() : super._();
+
+  factory _ProductUnitDto.fromJson(Map<String, dynamic> json) =
+      _$ProductUnitDtoImpl.fromJson;
+
+  @override
+  @JsonKey(name: "id")
+  String? get id;
+  @override
+  @JsonKey(name: "name")
+  String? get name;
+  @override
+  @JsonKey(name: "abbreviation")
+  String? get abbreviation;
+
+  /// Create a copy of ProductUnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @override
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  _$$ProductUnitDtoImplCopyWith<_$ProductUnitDtoImpl> get copyWith =>
+      throw _privateConstructorUsedError;
+}
+
 ProductDto _$ProductDtoFromJson(Map<String, dynamic> json) {
   return _ProductDto.fromJson(json);
 }
@@ -333,6 +550,16 @@ mixin _$ProductDto {
   String? get updatedAt => throw _privateConstructorUsedError;
   @JsonKey(name: "variants")
   List<ProductVariantDto>? get variants => throw _privateConstructorUsedError;
+  @JsonKey(name: "sell_by")
+  String? get sellBy => throw _privateConstructorUsedError;
+  @JsonKey(name: "unit_id")
+  String? get unitId => throw _privateConstructorUsedError;
+  @JsonKey(name: "unit_name")
+  String? get unitName => throw _privateConstructorUsedError;
+  @JsonKey(name: "unit_abbreviation")
+  String? get unitAbbreviation => throw _privateConstructorUsedError;
+  @JsonKey(name: "unit")
+  ProductUnitDto? get unit => throw _privateConstructorUsedError;
 
   /// Serializes this ProductDto to a JSON map.
   Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
@@ -369,7 +596,14 @@ abstract class $ProductDtoCopyWith<$Res> {
     @JsonKey(name: "created_at") String? createdAt,
     @JsonKey(name: "updated_at") String? updatedAt,
     @JsonKey(name: "variants") List<ProductVariantDto>? variants,
+    @JsonKey(name: "sell_by") String? sellBy,
+    @JsonKey(name: "unit_id") String? unitId,
+    @JsonKey(name: "unit_name") String? unitName,
+    @JsonKey(name: "unit_abbreviation") String? unitAbbreviation,
+    @JsonKey(name: "unit") ProductUnitDto? unit,
   });
+
+  $ProductUnitDtoCopyWith<$Res>? get unit;
 }
 
 /// @nodoc
@@ -404,6 +638,11 @@ class _$ProductDtoCopyWithImpl<$Res, $Val extends ProductDto>
     Object? createdAt = freezed,
     Object? updatedAt = freezed,
     Object? variants = freezed,
+    Object? sellBy = freezed,
+    Object? unitId = freezed,
+    Object? unitName = freezed,
+    Object? unitAbbreviation = freezed,
+    Object? unit = freezed,
   }) {
     return _then(
       _value.copyWith(
@@ -475,10 +714,44 @@ class _$ProductDtoCopyWithImpl<$Res, $Val extends ProductDto>
                 ? _value.variants
                 : variants // ignore: cast_nullable_to_non_nullable
                       as List<ProductVariantDto>?,
+            sellBy: freezed == sellBy
+                ? _value.sellBy
+                : sellBy // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            unitId: freezed == unitId
+                ? _value.unitId
+                : unitId // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            unitName: freezed == unitName
+                ? _value.unitName
+                : unitName // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            unitAbbreviation: freezed == unitAbbreviation
+                ? _value.unitAbbreviation
+                : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            unit: freezed == unit
+                ? _value.unit
+                : unit // ignore: cast_nullable_to_non_nullable
+                      as ProductUnitDto?,
           )
           as $Val,
     );
   }
+
+  /// Create a copy of ProductDto
+  /// with the given fields replaced by the non-null parameter values.
+  @override
+  @pragma('vm:prefer-inline')
+  $ProductUnitDtoCopyWith<$Res>? get unit {
+    if (_value.unit == null) {
+      return null;
+    }
+
+    return $ProductUnitDtoCopyWith<$Res>(_value.unit!, (value) {
+      return _then(_value.copyWith(unit: value) as $Val);
+    });
+  }
 }
 
 /// @nodoc
@@ -508,7 +781,15 @@ abstract class _$$ProductDtoImplCopyWith<$Res>
     @JsonKey(name: "created_at") String? createdAt,
     @JsonKey(name: "updated_at") String? updatedAt,
     @JsonKey(name: "variants") List<ProductVariantDto>? variants,
+    @JsonKey(name: "sell_by") String? sellBy,
+    @JsonKey(name: "unit_id") String? unitId,
+    @JsonKey(name: "unit_name") String? unitName,
+    @JsonKey(name: "unit_abbreviation") String? unitAbbreviation,
+    @JsonKey(name: "unit") ProductUnitDto? unit,
   });
+
+  @override
+  $ProductUnitDtoCopyWith<$Res>? get unit;
 }
 
 /// @nodoc
@@ -542,6 +823,11 @@ class __$$ProductDtoImplCopyWithImpl<$Res>
     Object? createdAt = freezed,
     Object? updatedAt = freezed,
     Object? variants = freezed,
+    Object? sellBy = freezed,
+    Object? unitId = freezed,
+    Object? unitName = freezed,
+    Object? unitAbbreviation = freezed,
+    Object? unit = freezed,
   }) {
     return _then(
       _$ProductDtoImpl(
@@ -613,6 +899,26 @@ class __$$ProductDtoImplCopyWithImpl<$Res>
             ? _value._variants
             : variants // ignore: cast_nullable_to_non_nullable
                   as List<ProductVariantDto>?,
+        sellBy: freezed == sellBy
+            ? _value.sellBy
+            : sellBy // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        unitId: freezed == unitId
+            ? _value.unitId
+            : unitId // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        unitName: freezed == unitName
+            ? _value.unitName
+            : unitName // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        unitAbbreviation: freezed == unitAbbreviation
+            ? _value.unitAbbreviation
+            : unitAbbreviation // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        unit: freezed == unit
+            ? _value.unit
+            : unit // ignore: cast_nullable_to_non_nullable
+                  as ProductUnitDto?,
       ),
     );
   }
@@ -639,6 +945,11 @@ class _$ProductDtoImpl extends _ProductDto {
     @JsonKey(name: "created_at") this.createdAt,
     @JsonKey(name: "updated_at") this.updatedAt,
     @JsonKey(name: "variants") final List<ProductVariantDto>? variants,
+    @JsonKey(name: "sell_by") this.sellBy,
+    @JsonKey(name: "unit_id") this.unitId,
+    @JsonKey(name: "unit_name") this.unitName,
+    @JsonKey(name: "unit_abbreviation") this.unitAbbreviation,
+    @JsonKey(name: "unit") this.unit,
   }) : _metadata = metadata,
        _variants = variants,
        super._();
@@ -713,9 +1024,25 @@ class _$ProductDtoImpl extends _ProductDto {
     return EqualUnmodifiableListView(value);
   }
 
+  @override
+  @JsonKey(name: "sell_by")
+  final String? sellBy;
+  @override
+  @JsonKey(name: "unit_id")
+  final String? unitId;
+  @override
+  @JsonKey(name: "unit_name")
+  final String? unitName;
+  @override
+  @JsonKey(name: "unit_abbreviation")
+  final String? unitAbbreviation;
+  @override
+  @JsonKey(name: "unit")
+  final ProductUnitDto? unit;
+
   @override
   String toString() {
-    return 'ProductDto(id: $id, organizationId: $organizationId, categoryId: $categoryId, sku: $sku, name: $name, description: $description, price: $price, cost: $cost, businessType: $businessType, imageUrl: $imageUrl, printerType: $printerType, printToChecker: $printToChecker, metadata: $metadata, isActive: $isActive, createdAt: $createdAt, updatedAt: $updatedAt, variants: $variants)';
+    return 'ProductDto(id: $id, organizationId: $organizationId, categoryId: $categoryId, sku: $sku, name: $name, description: $description, price: $price, cost: $cost, businessType: $businessType, imageUrl: $imageUrl, printerType: $printerType, printToChecker: $printToChecker, metadata: $metadata, isActive: $isActive, createdAt: $createdAt, updatedAt: $updatedAt, variants: $variants, sellBy: $sellBy, unitId: $unitId, unitName: $unitName, unitAbbreviation: $unitAbbreviation, unit: $unit)';
   }
 
   @override
@@ -749,12 +1076,19 @@ class _$ProductDtoImpl extends _ProductDto {
                 other.createdAt == createdAt) &&
             (identical(other.updatedAt, updatedAt) ||
                 other.updatedAt == updatedAt) &&
-            const DeepCollectionEquality().equals(other._variants, _variants));
+            const DeepCollectionEquality().equals(other._variants, _variants) &&
+            (identical(other.sellBy, sellBy) || other.sellBy == sellBy) &&
+            (identical(other.unitId, unitId) || other.unitId == unitId) &&
+            (identical(other.unitName, unitName) ||
+                other.unitName == unitName) &&
+            (identical(other.unitAbbreviation, unitAbbreviation) ||
+                other.unitAbbreviation == unitAbbreviation) &&
+            (identical(other.unit, unit) || other.unit == unit));
   }
 
   @JsonKey(includeFromJson: false, includeToJson: false)
   @override
-  int get hashCode => Object.hash(
+  int get hashCode => Object.hashAll([
     runtimeType,
     id,
     organizationId,
@@ -773,7 +1107,12 @@ class _$ProductDtoImpl extends _ProductDto {
     createdAt,
     updatedAt,
     const DeepCollectionEquality().hash(_variants),
-  );
+    sellBy,
+    unitId,
+    unitName,
+    unitAbbreviation,
+    unit,
+  ]);
 
   /// Create a copy of ProductDto
   /// with the given fields replaced by the non-null parameter values.
@@ -808,6 +1147,11 @@ abstract class _ProductDto extends ProductDto {
     @JsonKey(name: "created_at") final String? createdAt,
     @JsonKey(name: "updated_at") final String? updatedAt,
     @JsonKey(name: "variants") final List<ProductVariantDto>? variants,
+    @JsonKey(name: "sell_by") final String? sellBy,
+    @JsonKey(name: "unit_id") final String? unitId,
+    @JsonKey(name: "unit_name") final String? unitName,
+    @JsonKey(name: "unit_abbreviation") final String? unitAbbreviation,
+    @JsonKey(name: "unit") final ProductUnitDto? unit,
   }) = _$ProductDtoImpl;
   const _ProductDto._() : super._();
 
@@ -865,6 +1209,21 @@ abstract class _ProductDto extends ProductDto {
   @override
   @JsonKey(name: "variants")
   List<ProductVariantDto>? get variants;
+  @override
+  @JsonKey(name: "sell_by")
+  String? get sellBy;
+  @override
+  @JsonKey(name: "unit_id")
+  String? get unitId;
+  @override
+  @JsonKey(name: "unit_name")
+  String? get unitName;
+  @override
+  @JsonKey(name: "unit_abbreviation")
+  String? get unitAbbreviation;
+  @override
+  @JsonKey(name: "unit")
+  ProductUnitDto? get unit;
 
   /// Create a copy of ProductDto
   /// with the given fields replaced by the non-null parameter values.

lib/infrastructure/product/product_dtos.g.dart

@@ -27,6 +27,21 @@ Map<String, dynamic> _$$ListProductDtoImplToJson(
   'total_pages': instance.totalPages,
 };
 
+_$ProductUnitDtoImpl _$$ProductUnitDtoImplFromJson(Map<String, dynamic> json) =>
+    _$ProductUnitDtoImpl(
+      id: json['id'] as String?,
+      name: json['name'] as String?,
+      abbreviation: json['abbreviation'] as String?,
+    );
+
+Map<String, dynamic> _$$ProductUnitDtoImplToJson(
+  _$ProductUnitDtoImpl instance,
+) => <String, dynamic>{
+  'id': instance.id,
+  'name': instance.name,
+  'abbreviation': instance.abbreviation,
+};
+
 _$ProductDtoImpl _$$ProductDtoImplFromJson(Map<String, dynamic> json) =>
     _$ProductDtoImpl(
       id: json['id'] as String?,
@@ -48,6 +63,13 @@ _$ProductDtoImpl _$$ProductDtoImplFromJson(Map<String, dynamic> json) =>
       variants: (json['variants'] as List<dynamic>?)
           ?.map((e) => ProductVariantDto.fromJson(e as Map<String, dynamic>))
           .toList(),
+      sellBy: json['sell_by'] as String?,
+      unitId: json['unit_id'] as String?,
+      unitName: json['unit_name'] as String?,
+      unitAbbreviation: json['unit_abbreviation'] as String?,
+      unit: json['unit'] == null
+          ? null
+          : ProductUnitDto.fromJson(json['unit'] as Map<String, dynamic>),
     );
 
 Map<String, dynamic> _$$ProductDtoImplToJson(_$ProductDtoImpl instance) =>
@@ -69,6 +91,11 @@ Map<String, dynamic> _$$ProductDtoImplToJson(_$ProductDtoImpl instance) =>
       'created_at': instance.createdAt,
       'updated_at': instance.updatedAt,
       'variants': instance.variants,
+      'sell_by': instance.sellBy,
+      'unit_id': instance.unitId,
+      'unit_name': instance.unitName,
+      'unit_abbreviation': instance.unitAbbreviation,
+      'unit': instance.unit,
     };
 
 _$ProductVariantDtoImpl _$$ProductVariantDtoImplFromJson(

lib/infrastructure/product/repositories/product_repository.dart

@@ -3,6 +3,7 @@ import 'dart:developer';
 import 'package:dartz/dartz.dart';
 import 'package:injectable/injectable.dart';
 
+import '../../../common/service/unit_registry.dart';
 import '../../../domain/product/product.dart';
 import '../datasources/local_data_provider.dart';
 import '../datasources/remote_data_provider.dart';
@@ -12,10 +13,38 @@ import '../product_dtos.dart';
 class ProductRepository implements IProductRepository {
   final ProductRemoteDataProvider _remoteDataProvider;
   final ProductLocalDataProvider _localDataProvider;
+  final UnitRegistry _unitRegistry;
 
   final _logName = 'ProductRepository';
 
-  ProductRepository(this._remoteDataProvider, this._localDataProvider);
+  ProductRepository(
+    this._remoteDataProvider,
+    this._localDataProvider,
+    this._unitRegistry,
+  );
+
+  /// Response produk hanya dijamin membawa `unit_id`. Lengkapi nama dan
+  /// singkatannya dari master satuan supaya keranjang bisa menulis "4,2 ons".
+  Product _withUnit(Product product) {
+    if (!product.isSoldByWeight || product.unitId.isEmpty) return product;
+    if (product.unitAbbreviation.isNotEmpty && product.unitName.isNotEmpty) {
+      return product;
+    }
+
+    final unit = _unitRegistry.byId(product.unitId);
+    if (unit == null) return product;
+
+    return product.copyWith(
+      unitName: product.unitName.isNotEmpty ? product.unitName : unit.name,
+      unitAbbreviation: product.unitAbbreviation.isNotEmpty
+          ? product.unitAbbreviation
+          : unit.abbreviation,
+    );
+  }
+
+  List<Product> _withUnits(List<Product> products) =>
+      products.map(_withUnit).toList();
+
 
   @override
   Future<Either<ProductFailure, Product>> getProductById(String id) async {
@@ -33,7 +62,7 @@ class ProductRepository implements IProductRepository {
         );
       }
 
-      final productDomain = product.data!.toDomain();
+      final productDomain = _withUnit(product.data!.toDomain());
 
       log('✅ Product loaded: ${productDomain.name}', name: _logName);
       return Right(productDomain);
@@ -85,7 +114,9 @@ class ProductRepository implements IProductRepository {
 
       // 🧱 Bangun entity domain ListProduct
       final result = ListProduct(
-        products: cachedProducts.data!.map((p) => p.toDomain()).toList(),
+        products: _withUnits(
+          cachedProducts.data!.map((p) => p.toDomain()).toList(),
+        ),
         totalCount: totalCount,
         page: page,
         limit: limit,
@@ -132,7 +163,9 @@ class ProductRepository implements IProductRepository {
         return left(cachedProducts.error!);
       }
 
-      final products = cachedProducts.data!.map((p) => p.toDomain()).toList();
+      final products = _withUnits(
+        cachedProducts.data!.map((p) => p.toDomain()).toList(),
+      );
 
       final totalCount = await _localDataProvider.getTotalCount(
         categoryId: categoryId,
@@ -180,7 +213,9 @@ class ProductRepository implements IProductRepository {
       }
 
       // ✅ Mapping ke domain entity (kalau hasilnya masih berupa DTO)
-      final products = results.data!.map((p) => p.toDomain()).toList();
+      final products = _withUnits(
+        results.data!.map((p) => p.toDomain()).toList(),
+      );
 
       log(
         '✅ Local search completed: ${products.length} results',
@@ -369,7 +404,7 @@ class ProductRepository implements IProductRepository {
 
       final products = result.data!.toDomain();
 
-      return right(products);
+      return right(products.copyWith(products: _withUnits(products.products)));
     } catch (e, s) {
       log('getProducts', name: _logName, error: e, stackTrace: s);
       return left(const ProductFailure.unexpectedError());

lib/infrastructure/unit/datasources/local_data_provider.dart

@@ -0,0 +1,38 @@
+import 'dart:convert';
+
+import 'package:injectable/injectable.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import '../../../common/constant/local_storage_key.dart';
+import '../unit_dtos.dart';
+
+/// Satuan berjumlah sedikit dan jarang berubah, jadi cukup disimpan sebagai
+/// satu blob JSON di SharedPreferences — tidak perlu tabel sqflite sendiri.
+@injectable
+class UnitLocalDataProvider {
+  final SharedPreferences _sharedPreferences;
+
+  UnitLocalDataProvider(this._sharedPreferences);
+
+  Future<void> saveUnits(List<UnitDto> units) async {
+    final jsonString = jsonEncode(units.map((e) => e.toJson()).toList());
+    await _sharedPreferences.setString(LocalStorageKey.units, jsonString);
+  }
+
+  List<UnitDto> getUnits() {
+    final jsonString = _sharedPreferences.getString(LocalStorageKey.units);
+    if (jsonString == null || jsonString.isEmpty) return const [];
+
+    final decoded = jsonDecode(jsonString);
+    if (decoded is! List) return const [];
+
+    return decoded
+        .whereType<Map<String, dynamic>>()
+        .map(UnitDto.fromJson)
+        .toList();
+  }
+
+  Future<void> clearUnits() async {
+    await _sharedPreferences.remove(LocalStorageKey.units);
+  }
+}

lib/infrastructure/unit/datasources/remote_data_provider.dart

@@ -0,0 +1,37 @@
+import 'dart:developer';
+
+import 'package:data_channel/data_channel.dart';
+import 'package:injectable/injectable.dart';
+
+import '../../../common/api/api_client.dart';
+import '../../../common/api/api_failure.dart';
+import '../../../common/function/app_function.dart';
+import '../../../common/url/api_path.dart';
+import '../../../domain/unit/unit.dart';
+import '../unit_dtos.dart';
+
+@injectable
+class UnitRemoteDataProvider {
+  final ApiClient _apiClient;
+  final _logName = 'UnitRemoteDataProvider';
+
+  UnitRemoteDataProvider(this._apiClient);
+
+  Future<DC<UnitFailure, List<UnitDto>>> fetchUnits() async {
+    try {
+      final response = await _apiClient.get(
+        ApiPath.units,
+        headers: getAuthorizationHeader(),
+      );
+
+      if (response.data['data'] == null) {
+        return DC.error(const UnitFailure.empty());
+      }
+
+      return DC.data(UnitDto.listFromResponse(response.data['data']));
+    } on ApiFailure catch (e, s) {
+      log('fetchUnitsError', name: _logName, error: e, stackTrace: s);
+      return DC.error(UnitFailure.serverError(e));
+    }
+  }
+}

lib/infrastructure/unit/dtos/unit_dto.dart

@@ -0,0 +1,59 @@
+part of '../unit_dtos.dart';
+
+@freezed
+class UnitDto with _$UnitDto {
+  const UnitDto._();
+
+  const factory UnitDto({
+    @JsonKey(name: "id") String? id,
+    @JsonKey(name: "organization_id") String? organizationId,
+    @JsonKey(name: "name") String? name,
+    @JsonKey(name: "abbreviation") String? abbreviation,
+    @JsonKey(name: "is_active") bool? isActive,
+  }) = _UnitDto;
+
+  factory UnitDto.fromJson(Map<String, dynamic> json) =>
+      _$UnitDtoFromJson(json);
+
+  ProductUnit toDomain() => ProductUnit(
+    id: id ?? '',
+    organizationId: organizationId ?? '',
+    name: name ?? '',
+    abbreviation: abbreviation ?? '',
+    isActive: isActive ?? true,
+  );
+
+  factory UnitDto.fromDomain(ProductUnit unit) => UnitDto(
+    id: unit.id,
+    organizationId: unit.organizationId,
+    name: unit.name,
+    abbreviation: unit.abbreviation,
+    isActive: unit.isActive,
+  );
+
+  /// Response `/units` belum tentu berbentuk sama di setiap versi backend —
+  /// bisa `data: [...]` atau `data: { units: [...] }`. Terima keduanya supaya
+  /// POS tidak kehilangan satuan hanya karena pembungkusnya berbeda.
+  static List<UnitDto> listFromResponse(dynamic data) {
+    if (data is List) {
+      return data
+          .whereType<Map<String, dynamic>>()
+          .map(UnitDto.fromJson)
+          .toList();
+    }
+
+    if (data is Map<String, dynamic>) {
+      for (final key in const ['units', 'items', 'data']) {
+        final value = data[key];
+        if (value is List) {
+          return value
+              .whereType<Map<String, dynamic>>()
+              .map(UnitDto.fromJson)
+              .toList();
+        }
+      }
+    }
+
+    return const [];
+  }
+}

lib/infrastructure/unit/repositories/unit_repository.dart

@@ -0,0 +1,56 @@
+import 'dart:developer';
+
+import 'package:dartz/dartz.dart';
+import 'package:injectable/injectable.dart';
+
+import '../../../domain/unit/unit.dart';
+import '../datasources/local_data_provider.dart';
+import '../datasources/remote_data_provider.dart';
+
+@Injectable(as: IUnitRepository)
+class UnitRepository implements IUnitRepository {
+  final UnitRemoteDataProvider _remoteDataProvider;
+  final UnitLocalDataProvider _localDataProvider;
+
+  final _logName = 'UnitRepository';
+
+  UnitRepository(this._remoteDataProvider, this._localDataProvider);
+
+  @override
+  Future<Either<UnitFailure, List<ProductUnit>>> getUnits({
+    bool forceRefresh = false,
+  }) async {
+    try {
+      final cached = _localDataProvider.getUnits();
+
+      if (!forceRefresh && cached.isNotEmpty) {
+        log('📏 ${cached.length} satuan dari cache', name: _logName);
+        return right(cached.map((e) => e.toDomain()).toList());
+      }
+
+      final result = await _remoteDataProvider.fetchUnits();
+
+      if (result.hasError) {
+        // Offline bukan alasan untuk kehilangan satuan yang sudah pernah ada.
+        if (cached.isNotEmpty) {
+          log('⚠️ Gagal ambil satuan, pakai cache', name: _logName);
+          return right(cached.map((e) => e.toDomain()).toList());
+        }
+        return left(result.error!);
+      }
+
+      final units = result.data!;
+      await _localDataProvider.saveUnits(units);
+
+      log('✅ ${units.length} satuan disinkronkan', name: _logName);
+      return right(units.map((e) => e.toDomain()).toList());
+    } catch (e, s) {
+      log('❌ Error getUnits', name: _logName, error: e, stackTrace: s);
+      return left(UnitFailure.localStorageError(e.toString()));
+    }
+  }
+
+  @override
+  Future<List<ProductUnit>> cachedUnits() async =>
+      _localDataProvider.getUnits().map((e) => e.toDomain()).toList();
+}

lib/infrastructure/unit/unit_dtos.dart

@@ -0,0 +1,8 @@
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+import '../../domain/unit/unit.dart';
+
+part 'unit_dtos.freezed.dart';
+part 'unit_dtos.g.dart';
+
+part 'dtos/unit_dto.dart';

lib/infrastructure/unit/unit_dtos.freezed.dart

@@ -0,0 +1,280 @@
+// coverage:ignore-file
+// GENERATED CODE - DO NOT MODIFY BY HAND
+// ignore_for_file: type=lint
+// ignore_for_file: unused_element, deprecated_member_use, deprecated_member_use_from_same_package, use_function_type_syntax_for_parameters, unnecessary_const, avoid_init_to_null, invalid_override_different_default_values_named, prefer_expression_function_bodies, annotate_overrides, invalid_annotation_target, unnecessary_question_mark
+
+part of 'unit_dtos.dart';
+
+// **************************************************************************
+// FreezedGenerator
+// **************************************************************************
+
+T _$identity<T>(T value) => value;
+
+final _privateConstructorUsedError = UnsupportedError(
+  'It seems like you constructed your class using `MyClass._()`. This constructor is only meant to be used by freezed and you are not supposed to need it nor use it.\nPlease check the documentation here for more information: https://github.com/rrousselGit/freezed#adding-getters-and-methods-to-our-models',
+);
+
+UnitDto _$UnitDtoFromJson(Map<String, dynamic> json) {
+  return _UnitDto.fromJson(json);
+}
+
+/// @nodoc
+mixin _$UnitDto {
+  @JsonKey(name: "id")
+  String? get id => throw _privateConstructorUsedError;
+  @JsonKey(name: "organization_id")
+  String? get organizationId => throw _privateConstructorUsedError;
+  @JsonKey(name: "name")
+  String? get name => throw _privateConstructorUsedError;
+  @JsonKey(name: "abbreviation")
+  String? get abbreviation => throw _privateConstructorUsedError;
+  @JsonKey(name: "is_active")
+  bool? get isActive => throw _privateConstructorUsedError;
+
+  /// Serializes this UnitDto to a JSON map.
+  Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
+
+  /// Create a copy of UnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  $UnitDtoCopyWith<UnitDto> get copyWith => throw _privateConstructorUsedError;
+}
+
+/// @nodoc
+abstract class $UnitDtoCopyWith<$Res> {
+  factory $UnitDtoCopyWith(UnitDto value, $Res Function(UnitDto) then) =
+      _$UnitDtoCopyWithImpl<$Res, UnitDto>;
+  @useResult
+  $Res call({
+    @JsonKey(name: "id") String? id,
+    @JsonKey(name: "organization_id") String? organizationId,
+    @JsonKey(name: "name") String? name,
+    @JsonKey(name: "abbreviation") String? abbreviation,
+    @JsonKey(name: "is_active") bool? isActive,
+  });
+}
+
+/// @nodoc
+class _$UnitDtoCopyWithImpl<$Res, $Val extends UnitDto>
+    implements $UnitDtoCopyWith<$Res> {
+  _$UnitDtoCopyWithImpl(this._value, this._then);
+
+  // ignore: unused_field
+  final $Val _value;
+  // ignore: unused_field
+  final $Res Function($Val) _then;
+
+  /// Create a copy of UnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? id = freezed,
+    Object? organizationId = freezed,
+    Object? name = freezed,
+    Object? abbreviation = freezed,
+    Object? isActive = freezed,
+  }) {
+    return _then(
+      _value.copyWith(
+            id: freezed == id
+                ? _value.id
+                : id // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            organizationId: freezed == organizationId
+                ? _value.organizationId
+                : organizationId // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            name: freezed == name
+                ? _value.name
+                : name // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            abbreviation: freezed == abbreviation
+                ? _value.abbreviation
+                : abbreviation // ignore: cast_nullable_to_non_nullable
+                      as String?,
+            isActive: freezed == isActive
+                ? _value.isActive
+                : isActive // ignore: cast_nullable_to_non_nullable
+                      as bool?,
+          )
+          as $Val,
+    );
+  }
+}
+
+/// @nodoc
+abstract class _$$UnitDtoImplCopyWith<$Res> implements $UnitDtoCopyWith<$Res> {
+  factory _$$UnitDtoImplCopyWith(
+    _$UnitDtoImpl value,
+    $Res Function(_$UnitDtoImpl) then,
+  ) = __$$UnitDtoImplCopyWithImpl<$Res>;
+  @override
+  @useResult
+  $Res call({
+    @JsonKey(name: "id") String? id,
+    @JsonKey(name: "organization_id") String? organizationId,
+    @JsonKey(name: "name") String? name,
+    @JsonKey(name: "abbreviation") String? abbreviation,
+    @JsonKey(name: "is_active") bool? isActive,
+  });
+}
+
+/// @nodoc
+class __$$UnitDtoImplCopyWithImpl<$Res>
+    extends _$UnitDtoCopyWithImpl<$Res, _$UnitDtoImpl>
+    implements _$$UnitDtoImplCopyWith<$Res> {
+  __$$UnitDtoImplCopyWithImpl(
+    _$UnitDtoImpl _value,
+    $Res Function(_$UnitDtoImpl) _then,
+  ) : super(_value, _then);
+
+  /// Create a copy of UnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? id = freezed,
+    Object? organizationId = freezed,
+    Object? name = freezed,
+    Object? abbreviation = freezed,
+    Object? isActive = freezed,
+  }) {
+    return _then(
+      _$UnitDtoImpl(
+        id: freezed == id
+            ? _value.id
+            : id // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        organizationId: freezed == organizationId
+            ? _value.organizationId
+            : organizationId // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        name: freezed == name
+            ? _value.name
+            : name // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        abbreviation: freezed == abbreviation
+            ? _value.abbreviation
+            : abbreviation // ignore: cast_nullable_to_non_nullable
+                  as String?,
+        isActive: freezed == isActive
+            ? _value.isActive
+            : isActive // ignore: cast_nullable_to_non_nullable
+                  as bool?,
+      ),
+    );
+  }
+}
+
+/// @nodoc
+@JsonSerializable()
+class _$UnitDtoImpl extends _UnitDto {
+  const _$UnitDtoImpl({
+    @JsonKey(name: "id") this.id,
+    @JsonKey(name: "organization_id") this.organizationId,
+    @JsonKey(name: "name") this.name,
+    @JsonKey(name: "abbreviation") this.abbreviation,
+    @JsonKey(name: "is_active") this.isActive,
+  }) : super._();
+
+  factory _$UnitDtoImpl.fromJson(Map<String, dynamic> json) =>
+      _$$UnitDtoImplFromJson(json);
+
+  @override
+  @JsonKey(name: "id")
+  final String? id;
+  @override
+  @JsonKey(name: "organization_id")
+  final String? organizationId;
+  @override
+  @JsonKey(name: "name")
+  final String? name;
+  @override
+  @JsonKey(name: "abbreviation")
+  final String? abbreviation;
+  @override
+  @JsonKey(name: "is_active")
+  final bool? isActive;
+
+  @override
+  String toString() {
+    return 'UnitDto(id: $id, organizationId: $organizationId, name: $name, abbreviation: $abbreviation, isActive: $isActive)';
+  }
+
+  @override
+  bool operator ==(Object other) {
+    return identical(this, other) ||
+        (other.runtimeType == runtimeType &&
+            other is _$UnitDtoImpl &&
+            (identical(other.id, id) || other.id == id) &&
+            (identical(other.organizationId, organizationId) ||
+                other.organizationId == organizationId) &&
+            (identical(other.name, name) || other.name == name) &&
+            (identical(other.abbreviation, abbreviation) ||
+                other.abbreviation == abbreviation) &&
+            (identical(other.isActive, isActive) ||
+                other.isActive == isActive));
+  }
+
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  @override
+  int get hashCode => Object.hash(
+    runtimeType,
+    id,
+    organizationId,
+    name,
+    abbreviation,
+    isActive,
+  );
+
+  /// Create a copy of UnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  @override
+  @pragma('vm:prefer-inline')
+  _$$UnitDtoImplCopyWith<_$UnitDtoImpl> get copyWith =>
+      __$$UnitDtoImplCopyWithImpl<_$UnitDtoImpl>(this, _$identity);
+
+  @override
+  Map<String, dynamic> toJson() {
+    return _$$UnitDtoImplToJson(this);
+  }
+}
+
+abstract class _UnitDto extends UnitDto {
+  const factory _UnitDto({
+    @JsonKey(name: "id") final String? id,
+    @JsonKey(name: "organization_id") final String? organizationId,
+    @JsonKey(name: "name") final String? name,
+    @JsonKey(name: "abbreviation") final String? abbreviation,
+    @JsonKey(name: "is_active") final bool? isActive,
+  }) = _$UnitDtoImpl;
+  const _UnitDto._() : super._();
+
+  factory _UnitDto.fromJson(Map<String, dynamic> json) = _$UnitDtoImpl.fromJson;
+
+  @override
+  @JsonKey(name: "id")
+  String? get id;
+  @override
+  @JsonKey(name: "organization_id")
+  String? get organizationId;
+  @override
+  @JsonKey(name: "name")
+  String? get name;
+  @override
+  @JsonKey(name: "abbreviation")
+  String? get abbreviation;
+  @override
+  @JsonKey(name: "is_active")
+  bool? get isActive;
+
+  /// Create a copy of UnitDto
+  /// with the given fields replaced by the non-null parameter values.
+  @override
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  _$$UnitDtoImplCopyWith<_$UnitDtoImpl> get copyWith =>
+      throw _privateConstructorUsedError;
+}

lib/infrastructure/unit/unit_dtos.g.dart

@@ -0,0 +1,25 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'unit_dtos.dart';
+
+// **************************************************************************
+// JsonSerializableGenerator
+// **************************************************************************
+
+_$UnitDtoImpl _$$UnitDtoImplFromJson(Map<String, dynamic> json) =>
+    _$UnitDtoImpl(
+      id: json['id'] as String?,
+      organizationId: json['organization_id'] as String?,
+      name: json['name'] as String?,
+      abbreviation: json['abbreviation'] as String?,
+      isActive: json['is_active'] as bool?,
+    );
+
+Map<String, dynamic> _$$UnitDtoImplToJson(_$UnitDtoImpl instance) =>
+    <String, dynamic>{
+      'id': instance.id,
+      'organization_id': instance.organizationId,
+      'name': instance.name,
+      'abbreviation': instance.abbreviation,
+      'is_active': instance.isActive,
+    };

lib/injection.config.dart

@@ -88,6 +88,8 @@ import 'package:apskel_pos_flutter_v2/common/network/network_client.dart'
 import 'package:apskel_pos_flutter_v2/common/service/device_info_service.dart'
     as _i288;
 import 'package:apskel_pos_flutter_v2/common/service/fcm_service.dart' as _i312;
+import 'package:apskel_pos_flutter_v2/common/service/unit_registry.dart'
+    as _i584;
 import 'package:apskel_pos_flutter_v2/domain/analytic/analytic.dart' as _i346;
 import 'package:apskel_pos_flutter_v2/domain/auth/auth.dart' as _i776;
 import 'package:apskel_pos_flutter_v2/domain/category/category.dart' as _i502;
@@ -99,6 +101,7 @@ import 'package:apskel_pos_flutter_v2/domain/payment_method/payment_method.dart'
 import 'package:apskel_pos_flutter_v2/domain/printer/printer.dart' as _i104;
 import 'package:apskel_pos_flutter_v2/domain/product/product.dart' as _i44;
 import 'package:apskel_pos_flutter_v2/domain/table/table.dart' as _i983;
+import 'package:apskel_pos_flutter_v2/domain/unit/unit.dart' as _i320;
 import 'package:apskel_pos_flutter_v2/env.dart' as _i923;
 import 'package:apskel_pos_flutter_v2/infrastructure/analytic/datasources/remote_data_provider.dart'
     as _i708;
@@ -148,6 +151,12 @@ import 'package:apskel_pos_flutter_v2/infrastructure/table/datasources/remote_da
     as _i95;
 import 'package:apskel_pos_flutter_v2/infrastructure/table/repositories/table_repository.dart'
     as _i824;
+import 'package:apskel_pos_flutter_v2/infrastructure/unit/datasources/local_data_provider.dart'
+    as _i393;
+import 'package:apskel_pos_flutter_v2/infrastructure/unit/datasources/remote_data_provider.dart'
+    as _i1016;
+import 'package:apskel_pos_flutter_v2/infrastructure/unit/repositories/unit_repository.dart'
+    as _i228;
 import 'package:apskel_pos_flutter_v2/presentation/router/app_router.dart'
     as _i800;
 import 'package:connectivity_plus/connectivity_plus.dart' as _i895;
@@ -229,6 +238,9 @@ extension GetItInjectableX on _i174.GetIt {
     gh.factory<_i693.OutletLocalDatasource>(
       () => _i693.OutletLocalDatasource(gh<_i460.SharedPreferences>()),
     );
+    gh.factory<_i393.UnitLocalDataProvider>(
+      () => _i393.UnitLocalDataProvider(gh<_i460.SharedPreferences>()),
+    );
     gh.lazySingleton<_i457.ApiClient>(
       () => _i457.ApiClient(gh<_i361.Dio>(), gh<_i923.Env>()),
     );
@@ -279,6 +291,9 @@ extension GetItInjectableX on _i174.GetIt {
     gh.factory<_i95.TableRemoteDataProvider>(
       () => _i95.TableRemoteDataProvider(gh<_i457.ApiClient>()),
     );
+    gh.factory<_i1016.UnitRemoteDataProvider>(
+      () => _i1016.UnitRemoteDataProvider(gh<_i457.ApiClient>()),
+    );
     gh.factory<_i776.IAuthRepository>(
       () => _i941.AuthRepository(
         gh<_i370.AuthRemoteDataProvider>(),
@@ -291,13 +306,6 @@ extension GetItInjectableX on _i174.GetIt {
         gh<_i708.CategoryLocalDataProvider>(),
       ),
     );
-    gh.factory<_i46.LoginFormBloc>(
-      () => _i46.LoginFormBloc(
-        gh<_i776.IAuthRepository>(),
-        gh<_i312.FcmService>(),
-        gh<_i288.DeviceInfoService>(),
-      ),
-    );
     gh.factory<_i983.ITableRepository>(
       () => _i824.TableRepository(
         gh<_i95.TableRemoteDataProvider>(),
@@ -313,12 +321,6 @@ extension GetItInjectableX on _i174.GetIt {
     gh.factory<_i424.TableLoaderBloc>(
       () => _i424.TableLoaderBloc(gh<_i983.ITableRepository>()),
     );
-    gh.factory<_i44.IProductRepository>(
-      () => _i763.ProductRepository(
-        gh<_i707.ProductRemoteDataProvider>(),
-        gh<_i464.ProductLocalDataProvider>(),
-      ),
-    );
     gh.factory<_i552.IOutletRepository>(
       () => _i845.OutletRepository(
         gh<_i132.OutletRemoteDataProvider>(),
@@ -342,6 +344,12 @@ extension GetItInjectableX on _i174.GetIt {
         gh<_i552.IOutletRepository>(),
       ),
     );
+    gh.factory<_i320.IUnitRepository>(
+      () => _i228.UnitRepository(
+        gh<_i1016.UnitRemoteDataProvider>(),
+        gh<_i393.UnitLocalDataProvider>(),
+      ),
+    );
     gh.factory<_i143.ICustomerRepository>(
       () => _i385.CustomerRepository(gh<_i841.CustomerRemoteDataProvider>()),
     );
@@ -363,6 +371,9 @@ extension GetItInjectableX on _i174.GetIt {
     gh.factory<_i822.VoidFormBloc>(
       () => _i822.VoidFormBloc(gh<_i299.IOrderRepository>()),
     );
+    gh.lazySingleton<_i584.UnitRegistry>(
+      () => _i584.UnitRegistry(gh<_i320.IUnitRepository>()),
+    );
     gh.factory<_i683.CustomerLoaderBloc>(
       () => _i683.CustomerLoaderBloc(gh<_i143.ICustomerRepository>()),
     );
@@ -381,19 +392,19 @@ extension GetItInjectableX on _i174.GetIt {
     gh.factory<_i76.OutletLoaderBloc>(
       () => _i76.OutletLoaderBloc(gh<_i552.IOutletRepository>()),
     );
-    gh.factory<_i13.ProductLoaderBloc>(
-      () => _i13.ProductLoaderBloc(gh<_i44.IProductRepository>()),
-    );
-    gh.factory<_i741.SyncBloc>(
-      () => _i741.SyncBloc(
-        gh<_i44.IProductRepository>(),
-        gh<_i502.ICategoryRepository>(),
+    gh.factory<_i46.LoginFormBloc>(
+      () => _i46.LoginFormBloc(
+        gh<_i776.IAuthRepository>(),
+        gh<_i312.FcmService>(),
+        gh<_i288.DeviceInfoService>(),
+        gh<_i584.UnitRegistry>(),
       ),
     );
-    gh.factory<_i729.SyncSettingBloc>(
-      () => _i729.SyncSettingBloc(
-        gh<_i44.IProductRepository>(),
-        gh<_i502.ICategoryRepository>(),
+    gh.factory<_i44.IProductRepository>(
+      () => _i763.ProductRepository(
+        gh<_i707.ProductRemoteDataProvider>(),
+        gh<_i464.ProductLocalDataProvider>(),
+        gh<_i584.UnitRegistry>(),
       ),
     );
     gh.factory<_i911.CategoryAnalyticLoaderBloc>(
@@ -419,6 +430,22 @@ extension GetItInjectableX on _i174.GetIt {
     gh.factory<_i413.SalesAnalyticLoaderBloc>(
       () => _i413.SalesAnalyticLoaderBloc(gh<_i346.IAnalyticRepository>()),
     );
+    gh.factory<_i729.SyncSettingBloc>(
+      () => _i729.SyncSettingBloc(
+        gh<_i44.IProductRepository>(),
+        gh<_i502.ICategoryRepository>(),
+        gh<_i584.UnitRegistry>(),
+      ),
+    );
+    gh.factory<_i13.ProductLoaderBloc>(
+      () => _i13.ProductLoaderBloc(gh<_i44.IProductRepository>()),
+    );
+    gh.factory<_i741.SyncBloc>(
+      () => _i741.SyncBloc(
+        gh<_i44.IProductRepository>(),
+        gh<_i502.ICategoryRepository>(),
+      ),
+    );
     return this;
   }
 }

lib/main.dart

@@ -7,6 +7,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 
 import 'common/service/fcm_service.dart';
+import 'common/service/unit_registry.dart';
 import 'injection.dart';
 import 'presentation/app_widget.dart';
 
@@ -49,6 +50,10 @@ void main() async {
       // Inisialisasi FCM setelah DI siap
       await getIt<FcmService>().initialize();
 
+      // Master satuan dimuat dari cache lebih dulu supaya produk timbangan
+      // langsung punya label satuan, bahkan saat perangkat offline.
+      unawaited(getIt<UnitRegistry>().load());
+
       runApp(const AppWidget());
     },
     (error, stack) {

lib/presentation/components/card/order_menu.dart

@@ -5,6 +5,7 @@ import '../../../application/checkout/checkout_form/checkout_form_bloc.dart';
 import '../../../common/extension/extension.dart';
 import '../../../common/theme/theme.dart';
 import '../../../domain/product/product.dart';
+import '../dialog/dialog.dart';
 import '../image/image.dart';
 import '../spaces/space.dart';
 
@@ -26,8 +27,8 @@ class _OrderMenuState extends State<OrderMenu> {
 
     _controller.addListener(() {
       context.read<CheckoutFormBloc>().add(
-        CheckoutFormEvent.updateItemNotes(
-          widget.data.product,
+        CheckoutFormEvent.updateLineNotes(
+          widget.data.lineId,
           _controller.text,
         ),
       );
@@ -40,6 +41,29 @@ class _OrderMenuState extends State<OrderMenu> {
     super.dispose();
   }
 
+  void _removeLine() {
+    context.read<CheckoutFormBloc>().add(
+      CheckoutFormEvent.removeLine(widget.data.lineId),
+    );
+  }
+
+  /// Koreksi salah timbang: ubah angka pada baris yang sama, bukan menambah
+  /// baris baru.
+  void _editWeight() {
+    final bloc = context.read<CheckoutFormBloc>();
+    showDialog(
+      context: context,
+      builder: (context) => WeightInputDialog(
+        product: widget.data.product,
+        variant: widget.data.variant,
+        initialWeight: widget.data.weight,
+        onSubmit: (weight) => bloc.add(
+          CheckoutFormEvent.updateItemWeight(widget.data.lineId, weight),
+        ),
+      ),
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     return Column(
@@ -77,9 +101,10 @@ class _OrderMenuState extends State<OrderMenu> {
                   crossAxisAlignment: CrossAxisAlignment.start,
                   children: [
                     Text(
-                      (widget.data.product.price +
-                              (widget.data.variant?.priceModifier ?? 0))
-                          .currencyFormatRp,
+                      widget.data.isWeighted &&
+                              widget.data.product.unitLabel.isNotEmpty
+                          ? '${widget.data.unitPrice.currencyFormatRp} / ${widget.data.product.unitLabel}'
+                          : widget.data.unitPrice.currencyFormatRp,
                     ),
                     if (widget.data.variant != null)
                       Text(widget.data.variant?.name ?? ""),
@@ -87,60 +112,15 @@ class _OrderMenuState extends State<OrderMenu> {
                 ),
               ),
             ),
-            Row(
-              children: [
-                GestureDetector(
-                  onTap: () {
-                    context.read<CheckoutFormBloc>().add(
-                      CheckoutFormEvent.removeItem(
-                        widget.data.product,
-                        widget.data.variant,
-                      ),
-                    );
-                  },
-                  child: Container(
-                    width: 30,
-                    height: 30,
-                    color: AppColor.white,
-                    child: const Icon(
-                      Icons.remove_circle,
-                      color: AppColor.primary,
-                    ),
-                  ),
-                ),
-                SizedBox(
-                  width: 30.0,
-                  child: Center(child: Text(widget.data.quantity.toString())),
-                ),
-                GestureDetector(
-                  onTap: () {
-                    context.read<CheckoutFormBloc>().add(
-                      CheckoutFormEvent.addItem(
-                        widget.data.product,
-                        widget.data.variant,
-                      ),
-                    );
-                  },
-                  child: Container(
-                    width: 30,
-                    height: 30,
-                    color: AppColor.white,
-                    child: const Icon(
-                      Icons.add_circle,
-                      color: AppColor.primary,
-                    ),
-                  ),
-                ),
-              ],
-            ),
+            if (widget.data.isWeighted)
+              _buildWeightControl()
+            else
+              _buildQuantityStepper(),
             const SpaceWidth(8),
             SizedBox(
               width: 80.0,
               child: Text(
-                ((widget.data.product.price +
-                            (widget.data.variant?.priceModifier ?? 0)) *
-                        widget.data.quantity)
-                    .currencyFormatRp,
+                widget.data.lineTotal.currencyFormatRp,
                 textAlign: TextAlign.right,
                 style: const TextStyle(
                   color: AppColor.primary,
@@ -167,14 +147,7 @@ class _OrderMenuState extends State<OrderMenu> {
               ),
               const SpaceWidth(16.0),
               GestureDetector(
-                onTap: () {
-                  context.read<CheckoutFormBloc>().add(
-                    CheckoutFormEvent.removeItem(
-                      widget.data.product,
-                      widget.data.variant,
-                    ),
-                  );
-                },
+                onTap: _removeLine,
                 child: Container(
                   height: 40,
                   width: 40,
@@ -194,4 +167,77 @@ class _OrderMenuState extends State<OrderMenu> {
       ],
     );
   }
+
+  /// Baris berbobot tidak punya stepper — nilainya bukan cacah, dan angka 1
+  /// yang tersimpan di `quantity` akan terbaca seperti "satu ons".
+  Widget _buildWeightControl() {
+    return GestureDetector(
+      onTap: _editWeight,
+      child: Container(
+        padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
+        decoration: BoxDecoration(
+          color: AppColor.primary.withOpacity(0.08),
+          borderRadius: BorderRadius.circular(8.0),
+          border: Border.all(color: AppColor.primary.withOpacity(0.4)),
+        ),
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            Text(
+              widget.data.quantityLabel,
+              style: const TextStyle(
+                fontWeight: FontWeight.bold,
+                color: AppColor.primary,
+              ),
+            ),
+            const SpaceWidth(4),
+            const Icon(Icons.edit_outlined, size: 14, color: AppColor.primary),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildQuantityStepper() {
+    return Row(
+      children: [
+        GestureDetector(
+          onTap: () {
+            context.read<CheckoutFormBloc>().add(
+              CheckoutFormEvent.removeItem(
+                widget.data.product,
+                widget.data.variant,
+              ),
+            );
+          },
+          child: Container(
+            width: 30,
+            height: 30,
+            color: AppColor.white,
+            child: const Icon(Icons.remove_circle, color: AppColor.primary),
+          ),
+        ),
+        SizedBox(
+          width: 30.0,
+          child: Center(child: Text(widget.data.quantity.toString())),
+        ),
+        GestureDetector(
+          onTap: () {
+            context.read<CheckoutFormBloc>().add(
+              CheckoutFormEvent.addItem(
+                widget.data.product,
+                widget.data.variant,
+              ),
+            );
+          },
+          child: Container(
+            width: 30,
+            height: 30,
+            color: AppColor.white,
+            child: const Icon(Icons.add_circle, color: AppColor.primary),
+          ),
+        ),
+      ],
+    );
+  }
 }

lib/presentation/components/card/product_card.dart

@@ -17,18 +17,35 @@ class ProductCard extends StatelessWidget {
   Widget build(BuildContext context) {
     return GestureDetector(
       onTap: () {
-        if (product.isActive == true) {
-          if (product.variants.isEmpty) {
-            context.read<CheckoutFormBloc>().add(
-              CheckoutFormEvent.addItem(product, null),
-            );
-          } else {
+        if (product.isActive != true) return;
+
+        if (product.variants.isNotEmpty) {
           showDialog(
             context: context,
             builder: (context) => VariantDialog(product: product),
           );
+          return;
         }
+
+        // Produk timbangan tidak bisa langsung masuk keranjang — kasir harus
+        // menimbang dulu, dan tiap penimbangan jadi barisnya sendiri.
+        if (product.isSoldByWeight) {
+          final bloc = context.read<CheckoutFormBloc>();
+          showDialog(
+            context: context,
+            builder: (context) => WeightInputDialog(
+              product: product,
+              onSubmit: (weight) => bloc.add(
+                CheckoutFormEvent.addWeightedItem(product, null, weight),
+              ),
+            ),
+          );
+          return;
         }
+
+        context.read<CheckoutFormBloc>().add(
+          CheckoutFormEvent.addItem(product, null),
+        );
       },
       child: Container(
         decoration: BoxDecoration(
@@ -75,7 +92,11 @@ class ProductCard extends StatelessWidget {
                   Align(
                     alignment: Alignment.center,
                     child: Text(
-                      product.price.currencyFormatRp,
+                      product.isSoldByWeight
+                          ? '${product.price.currencyFormatRp} ${product.priceUnitLabel}'
+                              .trim()
+                          : product.price.currencyFormatRp,
+                      textAlign: TextAlign.center,
                       style: const TextStyle(
                         fontWeight: FontWeight.bold,
                         fontSize: 12,
@@ -89,31 +110,39 @@ class ProductCard extends StatelessWidget {
 
             BlocBuilder<CheckoutFormBloc, CheckoutFormState>(
               builder: (context, state) {
-                final totalQuantity = state.items
+                final lines = state.items
                     .where((item) => item.product.id == product.id)
-                    .map((item) => item.quantity)
-                    .fold(0, (sum, qty) => sum + qty);
+                    .toList();
+
+                if (lines.isEmpty) return const SizedBox.shrink();
+
+                // Untuk produk timbangan, jumlah baris tidak berarti apa-apa
+                // (selalu 1 per penimbangan) — yang informatif adalah total
+                // berat yang sudah masuk keranjang.
+                final label = product.isSoldByWeight
+                    ? '${lines.fold<double>(0, (sum, item) => sum + (item.weight ?? 0)).weightFormat} ${product.unitLabel}'
+                          .trim()
+                    : lines
+                          .fold<int>(0, (sum, item) => sum + item.quantity)
+                          .toString();
 
-                if (totalQuantity == 0) {
-                  return const SizedBox.shrink();
-                }
                 return Positioned(
                   top: 4,
                   right: 4,
                   child: Container(
-                    width: 40,
+                    constraints: const BoxConstraints(minWidth: 40),
                     height: 40,
-                    padding: const EdgeInsets.all(6),
+                    padding: const EdgeInsets.symmetric(horizontal: 6),
                     decoration: const BoxDecoration(
                       borderRadius: BorderRadius.all(Radius.circular(9.0)),
                       color: AppColor.primary,
                     ),
                     child: Center(
                       child: Text(
-                        totalQuantity.toString(),
-                        style: const TextStyle(
+                        label,
+                        style: TextStyle(
                           color: Colors.white,
-                          fontSize: 20,
+                          fontSize: product.isSoldByWeight ? 13 : 20,
                           fontWeight: FontWeight.bold,
                         ),
                       ),

lib/presentation/components/dialog/dialog.dart

@@ -24,6 +24,7 @@ import '../spaces/space.dart';
 part 'custom_modal_dialog.dart';
 part 'outlet_dialog.dart';
 part 'variant_dialog.dart';
+part 'weight_input_dialog.dart';
 part 'delivery_dialog.dart';
 part 'order_type_dialog.dart';
 part 'printer_bluetooth_dialog.dart';

lib/presentation/components/dialog/order/order_save_confirm_dialog.dart

@@ -163,7 +163,9 @@ class OrderSaveConfirmDialog extends StatelessWidget {
                                               overflow: TextOverflow.ellipsis,
                                             ),
                                             Text(
-                                              '${item.quantity} qty',
+                                              item.isWeighted
+                                                  ? item.quantityLabel
+                                                  : '${item.quantity} qty',
                                               style: AppStyle.sm.copyWith(
                                                 color: AppColor.textSecondary,
                                               ),
@@ -185,8 +187,7 @@ class OrderSaveConfirmDialog extends StatelessWidget {
                                           ),
                                         ),
                                         child: Text(
-                                          ((item.product.price) * item.quantity)
-                                              .currencyFormatRpV2,
+                                          item.lineTotal.currencyFormatRpV2,
                                           style: AppStyle.md.copyWith(
                                             fontWeight: FontWeight.bold,
                                             color: AppColor.primary,

lib/presentation/components/dialog/variant_dialog.dart

@@ -21,10 +21,33 @@ class VariantDialog extends StatelessWidget {
           return GestureDetector(
             onTap: () {
               // Aksi saat varian dipilih
-              context.maybePop();
-              context.read<CheckoutFormBloc>().add(
-                CheckoutFormEvent.addItem(product, variant),
+              final bloc = context.read<CheckoutFormBloc>();
+              // Context dialog ini mati begitu di-pop, jadi dialog lanjutan
+              // dibuka lewat context milik Navigator.
+              final navigator = Navigator.of(context, rootNavigator: true);
+              navigator.pop();
+
+              // Produk timbangan lanjut ke papan angka; varian hanya mengubah
+              // harga per satuannya.
+              if (product.isSoldByWeight) {
+                showDialog(
+                  context: navigator.context,
+                  builder: (context) => WeightInputDialog(
+                    product: product,
+                    variant: variant,
+                    onSubmit: (weight) => bloc.add(
+                      CheckoutFormEvent.addWeightedItem(
+                        product,
+                        variant,
+                        weight,
+                      ),
+                    ),
+                  ),
                 );
+                return;
+              }
+
+              bloc.add(CheckoutFormEvent.addItem(product, variant));
             },
             child: Container(
               width: (context.deviceWidth * 0.4 - 12 - 32) / 2 - 6, // 2 per row

lib/presentation/components/dialog/weight_input_dialog.dart

@@ -0,0 +1,267 @@
+part of 'dialog.dart';
+
+/// Papan angka desimal untuk produk yang dijual per timbangan.
+///
+/// Satu kali dialog ini ditutup dengan angka = satu penimbangan = satu baris
+/// keranjang. Untuk mengoreksi salah timbang, buka lagi baris yang sama lewat
+/// [initialWeight] alih-alih menambah baris baru.
+class WeightInputDialog extends StatefulWidget {
+  final Product product;
+  final ProductVariant? variant;
+  final double? initialWeight;
+  final ValueChanged<double> onSubmit;
+
+  const WeightInputDialog({
+    super.key,
+    required this.product,
+    required this.onSubmit,
+    this.variant,
+    this.initialWeight,
+  });
+
+  /// Berat terkecil yang diterima backend; di bawah ini membulat ke nol.
+  static const double minWeight = 0.001;
+
+  /// Backend membulatkan berat ke 3 desimal.
+  static const int maxDecimals = 3;
+
+  @override
+  State<WeightInputDialog> createState() => _WeightInputDialogState();
+}
+
+class _WeightInputDialogState extends State<WeightInputDialog> {
+  /// Angka disimpan sebagai teks supaya "4," dan "4,20" bisa diketik utuh
+  /// tanpa dinormalisasi di tengah pengetikan.
+  late String _input = _formatInitial(widget.initialWeight);
+
+  static String _formatInitial(double? weight) {
+    if (weight == null || weight <= 0) return '';
+    return weight
+        .toStringAsFixed(WeightInputDialog.maxDecimals)
+        .replaceFirst(RegExp(r'\.?0+$'), '')
+        .replaceAll('.', ',');
+  }
+
+  double get _weight => double.tryParse(_input.replaceAll(',', '.')) ?? 0;
+
+  bool get _isValid => _weight >= WeightInputDialog.minWeight;
+
+  double get _unitPrice =>
+      widget.product.price + (widget.variant?.priceModifier ?? 0);
+
+  String get _unitLabel => widget.product.unitLabel;
+
+  void _tapDigit(String digit) {
+    final separatorIndex = _input.indexOf(',');
+    if (separatorIndex != -1 &&
+        _input.length - separatorIndex - 1 >= WeightInputDialog.maxDecimals) {
+      return;
+    }
+
+    setState(() {
+      // Hindari "007": nol di depan hanya berarti sesuatu sebelum koma.
+      _input = _input == '0' ? digit : '$_input$digit';
+    });
+  }
+
+  void _tapSeparator() {
+    if (_input.contains(',')) return;
+    setState(() => _input = _input.isEmpty ? '0,' : '$_input,');
+  }
+
+  void _tapBackspace() {
+    if (_input.isEmpty) return;
+    setState(() => _input = _input.substring(0, _input.length - 1));
+  }
+
+  void _tapClear() => setState(() => _input = '');
+
+  void _submit() {
+    if (!_isValid) return;
+    final rounded = double.parse(
+      _weight.toStringAsFixed(WeightInputDialog.maxDecimals),
+    );
+    context.maybePop();
+    widget.onSubmit(rounded);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return CustomModalDialog(
+      title: widget.product.name,
+      subtitle: _unitLabel.isEmpty
+          ? 'Masukkan berat'
+          : 'Masukkan berat dalam $_unitLabel',
+      minWidth: 380,
+      maxWidth: 420,
+      minHeight: 0,
+      contentPadding: const EdgeInsets.all(16),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.stretch,
+        children: [
+          _buildDisplay(),
+          const SpaceHeight(16),
+          _buildKeypad(),
+          const SpaceHeight(16),
+          AppElevatedButton.filled(
+            borderRadius: 12,
+            disabled: !_isValid,
+            onPressed: _submit,
+            label: widget.initialWeight == null
+                ? 'Tambah ke Pesanan'
+                : 'Simpan Berat',
+          ),
+          if (_input.isNotEmpty && !_isValid) ...[
+            const SpaceHeight(8),
+            Text(
+              'Berat minimal 0,001${_unitLabel.isEmpty ? '' : ' $_unitLabel'}',
+              textAlign: TextAlign.center,
+              style: AppStyle.sm.copyWith(color: AppColor.error),
+            ),
+          ],
+        ],
+      ),
+    );
+  }
+
+  Widget _buildDisplay() {
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+      decoration: BoxDecoration(
+        color: AppColor.primary.withOpacity(0.06),
+        borderRadius: BorderRadius.circular(12),
+        border: Border.all(color: AppColor.primary.withOpacity(0.3)),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Row(
+            crossAxisAlignment: CrossAxisAlignment.baseline,
+            textBaseline: TextBaseline.alphabetic,
+            children: [
+              Expanded(
+                child: Text(
+                  _input.isEmpty ? '0' : _input,
+                  textAlign: TextAlign.right,
+                  style: AppStyle.xxl.copyWith(
+                    fontSize: 40,
+                    fontWeight: FontWeight.bold,
+                    color: _input.isEmpty
+                        ? AppColor.textSecondary
+                        : AppColor.black,
+                  ),
+                ),
+              ),
+              if (_unitLabel.isNotEmpty) ...[
+                const SpaceWidth(8),
+                Text(
+                  _unitLabel,
+                  style: AppStyle.lg.copyWith(color: AppColor.textSecondary),
+                ),
+              ],
+            ],
+          ),
+          const SpaceHeight(4),
+          Row(
+            mainAxisAlignment: MainAxisAlignment.spaceBetween,
+            children: [
+              Text(
+                '${_unitPrice.currencyFormatRpV2}'
+                '${_unitLabel.isEmpty ? '' : ' / $_unitLabel'}',
+                style: AppStyle.sm.copyWith(color: AppColor.textSecondary),
+              ),
+              Text(
+                (_unitPrice * _weight).currencyFormatRpV2,
+                style: AppStyle.lg.copyWith(
+                  fontWeight: FontWeight.bold,
+                  color: AppColor.primary,
+                ),
+              ),
+            ],
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildKeypad() {
+    const keys = [
+      ['1', '2', '3'],
+      ['4', '5', '6'],
+      ['7', '8', '9'],
+      [',', '0', 'hapus'],
+    ];
+
+    return Column(
+      children: [
+        for (final row in keys)
+          Padding(
+            padding: const EdgeInsets.only(bottom: 8),
+            child: Row(
+              children: [
+                for (final key in row)
+                  Expanded(
+                    child: Padding(
+                      padding: const EdgeInsets.symmetric(horizontal: 4),
+                      child: _KeypadButton(
+                        label: key,
+                        onTap: () {
+                          switch (key) {
+                            case ',':
+                              _tapSeparator();
+                            case 'hapus':
+                              _tapBackspace();
+                            default:
+                              _tapDigit(key);
+                          }
+                        },
+                        // Tahan lama untuk mengosongkan angka sekaligus.
+                        onLongPress: key == 'hapus' ? _tapClear : null,
+                      ),
+                    ),
+                  ),
+              ],
+            ),
+          ),
+      ],
+    );
+  }
+}
+
+class _KeypadButton extends StatelessWidget {
+  final String label;
+  final VoidCallback onTap;
+  final VoidCallback? onLongPress;
+
+  const _KeypadButton({
+    required this.label,
+    required this.onTap,
+    this.onLongPress,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final isBackspace = label == 'hapus';
+
+    return InkWell(
+      onTap: onTap,
+      onLongPress: onLongPress,
+      borderRadius: BorderRadius.circular(12),
+      child: Container(
+        height: 56,
+        alignment: Alignment.center,
+        decoration: BoxDecoration(
+          color: AppColor.white,
+          borderRadius: BorderRadius.circular(12),
+          border: Border.all(color: AppColor.border),
+        ),
+        child: isBackspace
+            ? const Icon(Icons.backspace_outlined, color: AppColor.primary)
+            : Text(
+                label,
+                style: AppStyle.xxl.copyWith(fontWeight: FontWeight.w600),
+              ),
+      ),
+    );
+  }
+}

lib/presentation/components/print/print_ui.dart

@@ -77,6 +77,7 @@ class PrintUi {
       bytes += builder.orderItem(
         productName: item.productName,
         quantity: item.quantity,
+        quantityLabel: item.isWeighted ? item.quantityLabel : null,
         unitPrice: item.unitPrice.currencyFormatRpV2,
         totalPrice: item.totalPrice.currencyFormatRpV2,
         variantName: item.productVariantName,
@@ -140,7 +141,7 @@ class PrintUi {
     // Items — qty NAMA (uppercase), variant indent
     for (final item in order.orderItems.where((e) => e.printToChecker)) {
       final name = item.productName.toUpperCase();
-      bytes += builder.itemText('${item.quantity} $name');
+      bytes += builder.itemText('${item.quantityLabel} $name');
       if (item.productVariantName.isNotEmpty) {
         bytes += builder.itemText('  ${item.productVariantName.toUpperCase()}', bold: false);
       }
@@ -196,7 +197,7 @@ class PrintUi {
 
       // Single item
       final name = item.productName.toUpperCase();
-      bytes += builder.itemText('${item.quantity} $name');
+      bytes += builder.itemText('${item.quantityLabel} $name');
       if (item.productVariantName.isNotEmpty) {
         bytes += builder.itemText('  ${item.productVariantName.toUpperCase()}', bold: false);
       }
@@ -252,7 +253,7 @@ class PrintUi {
 
       // Single item
       final name = item.productName.toUpperCase();
-      bytes += builder.itemText('${item.quantity} $name');
+      bytes += builder.itemText('${item.quantityLabel} $name');
       if (item.productVariantName.isNotEmpty) {
         bytes += builder.itemText('  ${item.productVariantName.toUpperCase()}', bold: false);
       }
@@ -359,6 +360,7 @@ class PrintUi {
       bytes += builder.orderItem(
         productName: item.productName,
         quantity: item.quantity,
+        quantityLabel: item.isWeighted ? item.quantityLabel : null,
         unitPrice: item.unitPrice.currencyFormatRpV2,
         totalPrice: item.totalPrice.currencyFormatRpV2,
         variantName: item.productVariantName,
@@ -439,6 +441,7 @@ class PrintUi {
       bytes += builder.orderItem(
         productName: item.productName,
         quantity: item.quantity,
+        quantityLabel: item.isWeighted ? item.quantityLabel : null,
         unitPrice: item.unitPrice.currencyFormatRpV2,
         totalPrice: item.totalPrice.currencyFormatRpV2,
         variantName: item.productVariantName,
@@ -530,6 +533,7 @@ class PrintUi {
       bytes += builder.orderItem(
         productName: item.productName,
         quantity: item.quantity,
+        quantityLabel: item.isWeighted ? item.quantityLabel : null,
         unitPrice: item.unitPrice.currencyFormatRpV2,
         totalPrice: item.totalPrice.currencyFormatRpV2,
         variantName: item.productVariantName,

lib/presentation/components/print/receipt_component_builder.dart

@@ -301,6 +301,10 @@ class ReceiptComponentBuilder {
   List<int> orderItem({
     required String productName,
     required int quantity,
+
+    /// Untuk baris berbobot, isi dengan "4,2 ons" — angka quantity-nya selalu
+    /// 1 dan akan salah dibaca di struk.
+    String? quantityLabel,
     required String unitPrice,
     required String totalPrice,
     String? variantName,
@@ -314,7 +318,10 @@ class ReceiptComponentBuilder {
         ? '$productName ($variantName)'
         : productName;
     bytes += textLeft(displayName, bold: true, fontType: fontType, height: height ?? _bodyHeight, width: width ?? _bodyWidth);
-    bytes += row2Columns('${quantity}x $unitPrice',  totalPrice, fontType: fontType, height: height ?? _bodyHeight, width: width ?? _bodyWidth,);
+    final quantityText = quantityLabel != null && quantityLabel.isNotEmpty
+        ? '$quantityLabel x $unitPrice'
+        : '${quantity}x $unitPrice';
+    bytes += row2Columns(quantityText, totalPrice, fontType: fontType, height: height ?? _bodyHeight, width: width ?? _bodyWidth,);
     if (notes != null && notes.isNotEmpty) {
       bytes += row2Columns('Note', notes, fontType: fontType, height: height ?? _bodyHeight, width: width ?? _bodyWidth, leftWidth: 4, rightWidth: 8);
     }

lib/presentation/pages/checkout/checkout_page.dart

@@ -7,6 +7,7 @@ import '../../../application/order/order_form/order_form_bloc.dart';
 import '../../../application/payment_method/payment_method_loader/payment_method_loader_bloc.dart';
 import '../../../application/table/table_loader/table_loader_bloc.dart';
 import '../../../common/theme/theme.dart';
+import '../../../domain/product/product.dart';
 import '../../../injection.dart';
 import '../../components/spaces/space.dart';
 import '../../components/toast/flushbar.dart';
@@ -86,14 +87,7 @@ class CheckoutPage extends StatelessWidget implements AutoRouteWrapper {
           tag: 'checkout_screen',
           child: BlocBuilder<CheckoutFormBloc, CheckoutFormState>(
             builder: (context, state) {
-              final price = state.items.fold(
-                0,
-                (previousValue, element) =>
-                    previousValue +
-                    (element.product.price.toInt() +
-                            (element.variant?.priceModifier.toInt() ?? 0)) *
-                        element.quantity,
-              );
+              final price = state.items.cartTotal.toInt();
 
               return Scaffold(
                 backgroundColor: AppColor.white,

lib/presentation/pages/main/pages/home/widgets/home_right_panel.dart

@@ -7,6 +7,7 @@ import 'package:flutter_bloc/flutter_bloc.dart';
 import '../../../../../../application/checkout/checkout_form/checkout_form_bloc.dart';
 import '../../../../../../common/extension/extension.dart';
 import '../../../../../../common/theme/theme.dart';
+import '../../../../../../domain/product/product.dart';
 import '../../../../../components/button/button.dart';
 import '../../../../../components/card/order_menu.dart';
 import '../../../../../components/spaces/space.dart';
@@ -21,15 +22,7 @@ class HomeRightPanel extends StatelessWidget {
   Widget build(BuildContext context) {
     return BlocBuilder<CheckoutFormBloc, CheckoutFormState>(
       builder: (context, state) {
-        final price = state.items.isEmpty
-            ? 0.0
-            : state.items
-                  .map(
-                    (e) =>
-                        (e.product.price + (e.variant?.priceModifier ?? 0)) *
-                        e.quantity,
-                  )
-                  .reduce((value, element) => value + element);
+        final price = state.items.cartTotal;
         log('🛒 Total Price: $price');
         return Align(
           alignment: Alignment.topCenter,
@@ -87,8 +80,12 @@ class HomeRightPanel extends StatelessWidget {
                       : ListView.separated(
                           shrinkWrap: true,
                           padding: const EdgeInsets.symmetric(horizontal: 16),
-                          itemBuilder: (context, index) =>
-                              OrderMenu(data: state.items[index]),
+                          itemBuilder: (context, index) => OrderMenu(
+                            // Baris berbobot bisa dihapus satu per satu, jadi
+                            // state tiap baris harus terikat ke identitasnya.
+                            key: ValueKey(state.items[index].lineId),
+                            data: state.items[index],
+                          ),
                           separatorBuilder: (context, index) =>
                               const SpaceHeight(1.0),
                           itemCount: state.items.length,

lib/presentation/pages/order/pages/success_add_item_order/widgets/success_add_item_order_right_panel.dart

@@ -3,6 +3,7 @@ import 'package:flutter/material.dart';
 import '../../../../../../application/checkout/checkout_form/checkout_form_bloc.dart';
 import '../../../../../../common/extension/extension.dart';
 import '../../../../../../common/theme/theme.dart';
+import '../../../../../../domain/product/product.dart';
 import '../../../../../components/spaces/space.dart';
 
 class SuccessAddItemOrderRightPanel extends StatelessWidget {
@@ -86,14 +87,7 @@ class SuccessAddItemOrderRightPanel extends StatelessWidget {
                 ],
               ),
               Text(
-                (checkoutState.items.fold(
-                  0,
-                  (previousValue, element) =>
-                      previousValue +
-                      (element.product.price.toInt() +
-                              (element.variant?.priceModifier.toInt() ?? 0)) *
-                          element.quantity,
-                )).toString().currencyFormatRpV2,
+                checkoutState.items.cartTotal.toInt().toString().currencyFormatRpV2,
                 style: AppStyle.md.copyWith(fontWeight: FontWeight.w600),
               ),
             ],
@@ -165,15 +159,10 @@ class SuccessAddItemOrderRightPanel extends StatelessWidget {
                     ],
                   ),
                   child: Text(
-                    (checkoutState.items.fold(
-                      0,
-                      (previousValue, element) =>
-                          previousValue +
-                          (element.product.price.toInt() +
-                                  (element.variant?.priceModifier.toInt() ??
-                                      0)) *
-                              element.quantity,
-                    )).toString().currencyFormatRpV2,
+                    checkoutState.items.cartTotal
+                        .toInt()
+                        .toString()
+                        .currencyFormatRpV2,
                     style: AppStyle.xl.copyWith(
                       fontWeight: FontWeight.bold,
                       color: Colors.white,
@@ -270,7 +259,7 @@ class SuccessAddItemOrderRightPanel extends StatelessWidget {
                   borderRadius: BorderRadius.circular(12),
                 ),
                 child: Text(
-                  '${item.quantity}x',
+                  (item.isWeighted ? item.quantityLabel : "${item.quantity}x"),
                   style: AppStyle.md.copyWith(
                     fontWeight: FontWeight.bold,
                     color: Colors.white,
@@ -279,11 +268,7 @@ class SuccessAddItemOrderRightPanel extends StatelessWidget {
               ),
               const SpaceHeight(8),
               Text(
-                ((item.product.price.toInt() +
-                            (item.variant?.priceModifier.toInt() ?? 0)) *
-                        item.quantity)
-                    .toString()
-                    .currencyFormatRpV2,
+                item.lineTotal.toInt().toString().currencyFormatRpV2,
                 style: AppStyle.lg.copyWith(
                   fontWeight: FontWeight.bold,
                   color: AppColor.primary,

lib/presentation/pages/order/pages/success_order/widgets/success_order_right_panel.dart

@@ -255,7 +255,7 @@ class SuccessOrderRightPanel extends StatelessWidget {
                   borderRadius: BorderRadius.circular(12),
                 ),
                 child: Text(
-                  '${item.quantity}x',
+                  (item.isWeighted ? item.quantityLabel : "${item.quantity}x"),
                   style: AppStyle.md.copyWith(
                     fontWeight: FontWeight.bold,
                     color: Colors.white,

lib/presentation/pages/order/widgets/order_list.dart

@@ -211,7 +211,9 @@ class OrderList extends StatelessWidget {
                               borderRadius: BorderRadius.circular(8),
                             ),
                             child: Text(
-                              'x${product.quantity}',
+                              (product.isWeighted
+                                  ? product.quantityLabel
+                                  : "x${product.quantity}"),
                               style: AppStyle.md.copyWith(
                                 fontWeight: FontWeight.w600,
                                 color: AppColor.primary,

lib/presentation/pages/payment/pages/payment_success/widgets/payment_success_right_panel.dart

@@ -255,7 +255,7 @@ class PaymentSuccessRightPanel extends StatelessWidget {
                   borderRadius: BorderRadius.circular(12),
                 ),
                 child: Text(
-                  '${item.quantity}x',
+                  (item.isWeighted ? item.quantityLabel : "${item.quantity}x"),
                   style: AppStyle.md.copyWith(
                     fontWeight: FontWeight.bold,
                     color: Colors.white,

lib/presentation/pages/payment/pages/payment_success_split_bill/widgets/payment_success_split_bill_right_panel.dart

@@ -118,7 +118,7 @@ class PaymentSuccessSplitBillRightPanel extends StatelessWidget {
                   borderRadius: BorderRadius.circular(12),
                 ),
                 child: Text(
-                  '${item.quantity}x',
+                  (item.isWeighted ? item.quantityLabel : "${item.quantity}x"),
                   style: AppStyle.md.copyWith(
                     fontWeight: FontWeight.bold,
                     color: Colors.white,

lib/presentation/pages/payment/widgets/payment_left_panel.dart

@@ -65,7 +65,9 @@ class PaymentLeftPanel extends StatelessWidget {
                           ),
                         ),
                         subtitle: Text(
-                          'Qty: ${item.quantity}  |  ${item.productVariantName}',
+                          item.isWeighted
+                              ? '${item.quantityLabel}  |  ${item.productVariantName}'
+                              : 'Qty: ${item.quantity}  |  ${item.productVariantName}',
                           style: AppStyle.sm,
                         ),
                         trailing: Text(

lib/presentation/pages/refund/pages/refund_success/widgets/refund_success_right_panel.dart

@@ -255,7 +255,7 @@ class RefundSuccessRightPanel extends StatelessWidget {
                   borderRadius: BorderRadius.circular(12),
                 ),
                 child: Text(
-                  '${item.quantity}x',
+                  (item.isWeighted ? item.quantityLabel : "${item.quantity}x"),
                   style: AppStyle.md.copyWith(
                     fontWeight: FontWeight.bold,
                     color: Colors.white,

lib/presentation/pages/refund/widgets/refund_left_panel.dart

@@ -62,7 +62,9 @@ class RefundLeftPanel extends StatelessWidget {
                         ),
                       ),
                     Text(
-                      'Qty: ${item.quantity} x Rp ${item.unitPrice.currencyFormatRpV2} ',
+                      item.isWeighted
+                          ? item.quantityPriceLabel
+                          : 'Qty: ${item.quantity} x ${item.unitPrice.currencyFormatRpV2}',
                       style: AppStyle.md.copyWith(
                         color: AppColor.textSecondary,
                       ),

lib/presentation/pages/split_bill/widgets/split_bill_left_panel.dart

@@ -160,7 +160,9 @@ class SplitBillLeftPanel extends StatelessWidget {
                         ),
                       ),
                     Text(
-                      'Qty: ${item.quantity} x Rp ${item.unitPrice.currencyFormatRpV2} ',
+                      item.isWeighted
+                          ? item.quantityPriceLabel
+                          : 'Qty: ${item.quantity} x ${item.unitPrice.currencyFormatRpV2}',
                       style: AppStyle.md.copyWith(
                         color: AppColor.textSecondary,
                       ),

lib/presentation/pages/split_bill/widgets/split_bill_right_panel.dart

@@ -332,13 +332,71 @@ class _SplitBillRightPanelState extends State<SplitBillRightPanel> {
                     ),
                   ),
                 Text(
-                  '${item.unitPrice.currencyFormatRpV2} per item',
+                  item.isWeighted
+                      ? '${item.unitPrice.currencyFormatRpV2} per ${item.unitLabel}'
+                      : '${item.unitPrice.currencyFormatRpV2} per item',
                   style: AppStyle.sm.copyWith(color: AppColor.textSecondary),
                 ),
               ],
             ),
           ),
-          Row(
+          // Baris berbobot hanya punya dua keadaan: belum dibayar atau lunas.
+          // Tidak ada nilai di antaranya, jadi stepper diganti tombol pilih.
+          if (item.isWeighted)
+            _buildWeightedLineSelector(item, selectedQty > 0, maxQty)
+          else
+            _buildQuantityStepper(item, selectedQty, maxQty),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildWeightedLineSelector(OrderItem item, bool selected, int maxQty) {
+    final canSelect = selected || maxQty > 0;
+
+    return GestureDetector(
+      onTap: () {
+        if (!canSelect) return;
+        context.read<SplitBillFormBloc>().add(
+          SplitBillFormEvent.itemQuantityChanged(
+            itemId: item.id,
+            quantity: selected ? 0 : 1,
+          ),
+        );
+      },
+      child: Container(
+        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
+        decoration: BoxDecoration(
+          color: selected ? AppColor.primary : Colors.transparent,
+          border: Border.all(
+            color: canSelect ? AppColor.primary : AppColor.border,
+          ),
+          borderRadius: BorderRadius.circular(4),
+        ),
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            Icon(
+              selected ? Icons.check_circle : Icons.radio_button_unchecked,
+              size: 16,
+              color: selected ? Colors.white : AppColor.textSecondary,
+            ),
+            const SizedBox(width: 6),
+            Text(
+              selected ? 'Dibayar' : 'Bayar baris',
+              style: AppStyle.sm.copyWith(
+                fontWeight: FontWeight.w600,
+                color: selected ? Colors.white : AppColor.textSecondary,
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildQuantityStepper(OrderItem item, int selectedQty, int maxQty) {
+    return Row(
       children: [
         GestureDetector(
           onTap: () {
@@ -363,9 +421,7 @@ class _SplitBillRightPanelState extends State<SplitBillRightPanel> {
             child: Icon(
               Icons.remove,
               size: 16,
-                    color: selectedQty > 0
-                        ? Colors.white
-                        : AppColor.textSecondary,
+              color: selectedQty > 0 ? Colors.white : AppColor.textSecondary,
             ),
           ),
         ),
@@ -402,9 +458,7 @@ class _SplitBillRightPanelState extends State<SplitBillRightPanel> {
             width: 32,
             height: 32,
             decoration: BoxDecoration(
-                    color: selectedQty < maxQty
-                        ? AppColor.primary
-                        : AppColor.border,
+              color: selectedQty < maxQty ? AppColor.primary : AppColor.border,
               borderRadius: BorderRadius.circular(4),
             ),
             child: Icon(
@@ -417,9 +471,6 @@ class _SplitBillRightPanelState extends State<SplitBillRightPanel> {
           ),
         ),
       ],
-          ),
-        ],
-      ),
     );
   }
 
@@ -510,7 +561,10 @@ class _SplitBillRightPanelState extends State<SplitBillRightPanel> {
             splitItems.add(
               originalItem.copyWith(
                 quantity: quantity,
-                totalPrice: (originalItem.unitPrice) * quantity,
+                // Baris berbobot dibayar penuh; nilainya sudah weight x harga.
+                totalPrice: originalItem.isWeighted
+                    ? originalItem.totalPrice
+                    : (originalItem.unitPrice) * quantity,
               ),
             );
           }

lib/presentation/pages/void/widgets/void_product_card.dart

@@ -71,7 +71,9 @@ class VoidProductCard extends StatelessWidget {
                               borderRadius: BorderRadius.circular(12),
                             ),
                             child: Text(
-                              'Qty: ${item.quantity}',
+                              item.isWeighted
+                                  ? item.quantityLabel
+                                  : 'Qty: ${item.quantity}',
                               style: AppStyle.sm.copyWith(
                                 fontWeight: FontWeight.w500,
                                 color: Colors.blue[700],
@@ -112,65 +114,13 @@ class VoidProductCard extends StatelessWidget {
                 ),
 
                 if (canSelect) ...[
-                  Container(
-                    decoration: BoxDecoration(
-                      border: Border.all(color: AppColor.border),
-                      borderRadius: BorderRadius.circular(6),
-                    ),
-                    child: Row(
-                      mainAxisSize: MainAxisSize.min,
-                      children: [
-                        // Decrease Button
-                        InkWell(
-                          onTap: onTapDecrease,
-                          child: Container(
-                            padding: const EdgeInsets.all(8),
-                            child: Icon(
-                              Icons.remove,
-                              size: 16,
-                              color: voidQty > 0
-                                  ? AppColor.primary
-                                  : Colors.grey[400],
-                            ),
-                          ),
-                        ),
-
-                        // Quantity Display
-                        Container(
-                          padding: const EdgeInsets.symmetric(
-                            horizontal: 16,
-                            vertical: 8,
-                          ),
-                          decoration: const BoxDecoration(
-                            border: Border.symmetric(
-                              vertical: BorderSide(color: AppColor.border),
-                            ),
-                          ),
-                          child: Text(
-                            '$voidQty',
-                            style: AppStyle.sm.copyWith(
-                              fontWeight: FontWeight.w600,
-                            ),
-                          ),
-                        ),
-
-                        // Increase Button
-                        InkWell(
-                          onTap: onTapIncrease,
-                          child: Container(
-                            padding: const EdgeInsets.all(8),
-                            child: Icon(
-                              Icons.add,
-                              size: 16,
-                              color: voidQty < (item.quantity)
-                                  ? AppColor.primary
-                                  : Colors.grey[400],
-                            ),
-                          ),
-                        ),
-                      ],
-                    ),
-                  ),
+                  // Baris berbobot bersifat utuh: dibatalkan seluruhnya atau
+                  // tidak sama sekali, jadi yang ditawarkan tombol pilih baris
+                  // — bukan stepper jumlah.
+                  if (item.isWeighted)
+                    _buildLineSelector()
+                  else
+                    _buildQuantityStepper(),
                   const SpaceWidth(20),
                 ],
                 // Price
@@ -195,7 +145,7 @@ class VoidProductCard extends StatelessWidget {
                           borderRadius: BorderRadius.circular(4),
                         ),
                         child: Text(
-                          'Void: ${((item.unitPrice) * voidQty).currencyFormatRpV2}',
+                          'Void: ${(item.isWeighted ? item.totalPrice : (item.unitPrice) * voidQty).currencyFormatRpV2}',
                           style: AppStyle.sm.copyWith(
                             fontSize: 12,
                             color: AppColor.error,
@@ -214,4 +164,97 @@ class VoidProductCard extends StatelessWidget {
       ),
     );
   }
+
+  /// Pilih atau lepas satu baris berbobot secara utuh.
+  Widget _buildLineSelector() {
+    final selected = voidQty > 0;
+
+    return InkWell(
+      onTap: selected ? onTapDecrease : onTapIncrease,
+      borderRadius: BorderRadius.circular(6),
+      child: Container(
+        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
+        decoration: BoxDecoration(
+          color: selected ? AppColor.primary : Colors.transparent,
+          border: Border.all(
+            color: selected ? AppColor.primary : AppColor.border,
+          ),
+          borderRadius: BorderRadius.circular(6),
+        ),
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            Icon(
+              selected ? Icons.check_circle : Icons.radio_button_unchecked,
+              size: 16,
+              color: selected ? AppColor.white : AppColor.textSecondary,
+            ),
+            const SpaceWidth(6),
+            Text(
+              selected ? 'Dipilih' : 'Pilih baris',
+              style: AppStyle.sm.copyWith(
+                fontWeight: FontWeight.w600,
+                color: selected ? AppColor.white : AppColor.textSecondary,
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildQuantityStepper() {
+    return Container(
+      decoration: BoxDecoration(
+        border: Border.all(color: AppColor.border),
+        borderRadius: BorderRadius.circular(6),
+      ),
+      child: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          // Decrease Button
+          InkWell(
+            onTap: onTapDecrease,
+            child: Container(
+              padding: const EdgeInsets.all(8),
+              child: Icon(
+                Icons.remove,
+                size: 16,
+                color: voidQty > 0 ? AppColor.primary : Colors.grey[400],
+              ),
+            ),
+          ),
+
+          // Quantity Display
+          Container(
+            padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+            decoration: const BoxDecoration(
+              border: Border.symmetric(
+                vertical: BorderSide(color: AppColor.border),
+              ),
+            ),
+            child: Text(
+              '$voidQty',
+              style: AppStyle.sm.copyWith(fontWeight: FontWeight.w600),
+            ),
+          ),
+
+          // Increase Button
+          InkWell(
+            onTap: onTapIncrease,
+            child: Container(
+              padding: const EdgeInsets.all(8),
+              child: Icon(
+                Icons.add,
+                size: 16,
+                color: voidQty < (item.quantity)
+                    ? AppColor.primary
+                    : Colors.grey[400],
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
 }

test/weight_based_products_test.dart

@@ -0,0 +1,139 @@
+import 'package:apskel_pos_flutter_v2/application/checkout/checkout_form/checkout_form_bloc.dart';
+import 'package:apskel_pos_flutter_v2/common/types/sell_by.dart';
+import 'package:apskel_pos_flutter_v2/domain/order/order.dart';
+import 'package:apskel_pos_flutter_v2/domain/product/product.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+/// Ikan Tude — Rp 4.500 per ons.
+final ikanTude = Product.empty().copyWith(
+  id: 'ikan-tude',
+  name: 'Ikan Tude',
+  price: 4500,
+  isActive: true,
+  sellBy: SellBy.weight,
+  unitId: 'unit-ons',
+  unitName: 'Ons',
+  unitAbbreviation: 'ons',
+);
+
+final nasiGoreng = Product.empty().copyWith(
+  id: 'nasi-goreng',
+  name: 'Nasi Goreng',
+  price: 25000,
+  isActive: true,
+);
+
+void main() {
+  group('keranjang produk timbangan', () {
+    test('dua penimbangan produk yang sama menjadi dua baris', () async {
+      final bloc = CheckoutFormBloc();
+
+      bloc.add(CheckoutFormEvent.addWeightedItem(ikanTude, null, 4.2));
+      bloc.add(CheckoutFormEvent.addWeightedItem(ikanTude, null, 5.6));
+      await bloc.stream.firstWhere((s) => s.items.length == 2);
+
+      final items = bloc.state.items;
+      expect(items.length, 2);
+      expect(items.map((e) => e.weight), [4.2, 5.6]);
+      expect(items.every((e) => e.quantity == 1), isTrue);
+      expect(items[0].lineId, isNot(items[1].lineId));
+    });
+
+    test('produk cacah tetap digabung jadi satu baris', () async {
+      final bloc = CheckoutFormBloc();
+
+      bloc.add(CheckoutFormEvent.addItem(nasiGoreng, null));
+      bloc.add(CheckoutFormEvent.addItem(nasiGoreng, null));
+      await bloc.stream.firstWhere((s) => s.items.isNotEmpty && s.items.first.quantity == 2);
+
+      expect(bloc.state.items.length, 1);
+      expect(bloc.state.items.first.quantity, 2);
+    });
+
+    test('produk timbangan tidak bisa masuk tanpa berat', () async {
+      final bloc = CheckoutFormBloc();
+
+      bloc.add(CheckoutFormEvent.addItem(ikanTude, null));
+      await Future<void>.delayed(Duration.zero);
+
+      expect(bloc.state.items, isEmpty);
+    });
+
+    test('total baris dihitung berat x harga satuan', () {
+      final line = ProductQuantity(
+        product: ikanTude,
+        quantity: 1,
+        notes: '',
+        weight: 4.2,
+      );
+
+      expect(line.lineTotal, closeTo(18900, 0.001));
+      expect(line.quantityLabel, '4,2 ons');
+    });
+
+    test('total keranjang mencampur baris berbobot dan baris cacah', () {
+      final items = [
+        ProductQuantity(
+          product: ikanTude,
+          quantity: 1,
+          notes: '',
+          weight: 4.2,
+        ),
+        ProductQuantity(product: nasiGoreng, quantity: 2, notes: ''),
+      ];
+
+      expect(items.cartTotal, closeTo(18900 + 50000, 0.001));
+      expect(items.cartItemCount, 3);
+    });
+  });
+
+  group('permintaan ke backend', () {
+    test('baris berbobot dikirim quantity 1 dan membawa berat', () {
+      final request = OrderItemRequest.fromProductQuantity(
+        ProductQuantity(
+          product: ikanTude,
+          quantity: 1,
+          notes: '',
+          weight: 4.2,
+        ),
+      );
+
+      expect(request.quantity, 1);
+      expect(request.weight, 4.2);
+      expect(request.unitPrice, 4500);
+    });
+
+    test('produk cacah tidak membawa berat sama sekali', () {
+      final request = OrderItemRequest.fromProductQuantity(
+        ProductQuantity(product: nasiGoreng, quantity: 2, notes: ''),
+      );
+
+      expect(request.quantity, 2);
+      expect(request.weight, isNull);
+    });
+  });
+
+  group('tampilan baris pesanan', () {
+    test('baris berbobot memakai berat, bukan quantity', () {
+      final item = OrderItem.empty().copyWith(
+        quantity: 1,
+        unitPrice: 4500,
+        totalPrice: 18900,
+        weight: 4.2,
+        unitAbbreviation: 'ons',
+      );
+
+      expect(item.isWeighted, isTrue);
+      expect(item.quantityLabel, '4,2 ons');
+      expect(item.quantityPriceLabel, '4,2 ons x Rp 4.500');
+    });
+
+    test('baris biasa tetap memakai quantity', () {
+      final item = OrderItem.empty().copyWith(quantity: 2, unitPrice: 25000);
+
+      expect(item.isWeighted, isFalse);
+      expect(item.quantityLabel, '2');
+      expect(item.quantityPriceLabel, '2 x Rp 25.000');
+    });
+  });
+}