third commit

lib/app/providers.dart

@@ -30,13 +30,25 @@ final transactionRepositoryProvider = Provider<TransactionRepository>(
   (ref) => TransactionRepositoryImpl(ref.watch(localStoreProvider)),
 );
 
+/// Mirrors the Settings "Simulate offline" switch so the header can show it.
+///
+/// Without this the terminal claims LIVE while every call is being failed on
+/// purpose, which reads as a real network fault.
+final simulateOfflineProvider = StateProvider<bool>((ref) => false);
+
 /// Simulated back-office endpoints. Held as singletons so the offline toggle
 /// in Settings affects every call.
-final remoteCatalogueProvider =
+final remoteCatalogueProvider = Provider<RemoteCatalogueSource>(
-    Provider<RemoteCatalogueSource>((ref) => RemoteCatalogueSource());
+  (ref) => RemoteCatalogueSource(
+    isOffline: () => ref.read(simulateOfflineProvider),
+  ),
+);
 
-final remoteOrderSinkProvider =
+final remoteOrderSinkProvider = Provider<RemoteOrderSink>(
-    Provider<RemoteOrderSink>((ref) => RemoteOrderSink());
+  (ref) => RemoteOrderSink(
+    isOffline: () => ref.read(simulateOfflineProvider),
+  ),
+);
 
 final syncRepositoryProvider = Provider<SyncRepository>(
   (ref) => SyncRepositoryImpl(

lib/core/constants/app_constants.dart

@@ -6,6 +6,16 @@ class AppConstants {
   static const String storeName = 'Nearle Daily';
   static const String storeAddress = '12 Gandhipuram Main Rd, Coimbatore 641012';
   static const String storeGstin = '33ABCDE1234F1Z5';
+  static const String storeCin = 'U52190TZ2024PTC012345';
+  static const String storeFssai = '12417812000447';
+  static const String storeLegalName = 'Nearle Retail Private Limited';
+
+  /// Place of supply, printed on the tax invoice.
+  static const String stateCode = '33';
+  static const String stateName = 'TN';
+
+  static const String storeCode = '6709';
+  static const String posNumber = 'R120';
   static const String storePhone = '+91 90000 12345';
   static const String currencySymbol = '\u20B9';
   static const String locale = 'en_IN';

lib/core/services/receipt_service.dart

@@ -4,7 +4,10 @@ import 'package:flutter/foundation.dart';
 import 'package:pdf/pdf.dart';
 import 'package:pdf/widgets.dart' as pw;
 import 'package:printing/printing.dart';
+import 'package:url_launcher/url_launcher.dart';
 
+import '../../domain/entities/cart.dart';
+import '../utils/extensions.dart';
 import '../../domain/entities/transaction.dart';
 import '../constants/app_constants.dart';
 import '../utils/formatters.dart';
@@ -18,40 +21,66 @@ class ReceiptService {
   /// 80mm roll with a small safety margin.
   static const double _rollWidth = 78 * PdfPageFormat.mm;
 
+  /// One GST slab's worth of the bill, as the invoice groups it.
+  ///
+  /// A compliant Indian tax invoice lists items under their rate and then
+  /// repeats the arithmetic in a breakup table, so both are derived once here.
+  static List<_Slab> _slabs(SaleTransaction txn) {
+    final cart = txn.cart;
+
+    // Bill-level discounts are spread across lines, so the slab figures still
+    // add up to the amount actually charged.
+    final factor = cart.subtotal <= 0 ? 1.0 : cart.netAmount / cart.subtotal;
+
+    final grouped = <double, List<CartLine>>{};
+    for (final line in cart.lines) {
+      grouped.putIfAbsent(line.product.gstRate, () => []).add(line);
+    }
+
+    final rates = grouped.keys.toList()..sort();
+    return [
+      for (var i = 0; i < rates.length; i++)
+        _Slab(
+          index: i + 1,
+          rate: rates[i],
+          lines: grouped[rates[i]]!,
+          factor: factor,
+        ),
+    ];
+  }
+
   Future<Uint8List> build(SaleTransaction txn) async {
     final doc = pw.Document(title: txn.invoiceNumber);
-    final font = await PdfGoogleFonts.interRegular();
+    final font = await PdfGoogleFonts.robotoMonoRegular();
-    final bold = await PdfGoogleFonts.interSemiBold();
+    final bold = await PdfGoogleFonts.robotoMonoBold();
 
-    final cart = txn.cart;
+    final slabs = _slabs(txn);
 
     doc.addPage(
       pw.Page(
         pageFormat: PdfPageFormat(
           _rollWidth,
           double.infinity,
-          marginAll: 6 * PdfPageFormat.mm,
+          marginAll: 5 * PdfPageFormat.mm,
         ),
         theme: pw.ThemeData.withFont(base: font, bold: bold),
         build: (context) => pw.Column(
           crossAxisAlignment: pw.CrossAxisAlignment.stretch,
           children: [
             _header(txn),
-            _divider(),
+            _savingsLine(txn),
+            _rule(),
+            _invoiceTitle(),
             _meta(txn),
-            _divider(),
+            _rule(),
-            _itemsTable(txn),
+            _itemsBySlab(slabs),
-            _divider(),
+            _rule(),
             _totals(txn),
-            _divider(),
+            pw.SizedBox(height: 4),
-            _taxSummary(txn),
+            _gstBreakup(txn, slabs),
-            _divider(),
+            _rule(),
-            _payments(txn),
+            _references(txn),
-            if (cart.customer != null) ...[
+            pw.SizedBox(height: 6),
-              _divider(),
-              _loyalty(txn),
-            ],
-            pw.SizedBox(height: 8),
             _footer(txn),
           ],
         ),
@@ -66,241 +95,370 @@ class ReceiptService {
         pw.Text(
           AppConstants.storeName.toUpperCase(),
           style: pw.TextStyle(fontSize: 15, fontWeight: pw.FontWeight.bold),
-          textAlign: pw.TextAlign.center,
         ),
+        pw.Text(AppConstants.storeLegalName,
+            style: const pw.TextStyle(fontSize: 7)),
         pw.SizedBox(height: 2),
-        pw.Text(
+        pw.Text(AppConstants.storeAddress,
-          AppConstants.storeAddress,
+            style: const pw.TextStyle(fontSize: 6.5),
-          style: const pw.TextStyle(fontSize: 7),
+            textAlign: pw.TextAlign.center),
-          textAlign: pw.TextAlign.center,
+        pw.Text('Customer care : ${AppConstants.storePhone}',
-        ),
+            style: const pw.TextStyle(fontSize: 6.5)),
-        pw.Text(
+        pw.Text('CIN No : ${AppConstants.storeCin}',
-          'GSTIN: ${AppConstants.storeGstin}  |  ${AppConstants.storePhone}',
+            style: const pw.TextStyle(fontSize: 6.5)),
-          style: const pw.TextStyle(fontSize: 7),
+        pw.Text('GSTIN : ${AppConstants.storeGstin}',
-          textAlign: pw.TextAlign.center,
+            style: const pw.TextStyle(fontSize: 6.5)),
-        ),
+        pw.Text('FSSAI Lic No : ${AppConstants.storeFssai}',
-        pw.SizedBox(height: 4),
+            style: const pw.TextStyle(fontSize: 6.5)),
-        pw.Text(
+      ]);
-          'TAX INVOICE',
+
-          style: pw.TextStyle(fontSize: 9, fontWeight: pw.FontWeight.bold),
+  pw.Widget _savingsLine(SaleTransaction txn) {
-        ),
+    final saved = _grossSalesValue(txn) - txn.cart.netAmount;
+    if (saved <= 0) return pw.SizedBox(height: 4);
+
+    return pw.Padding(
+      padding: const pw.EdgeInsets.symmetric(vertical: 4),
+      child: pw.Text(
+        'You have saved Rs.${saved.toStringAsFixed(2)}',
+        style: pw.TextStyle(fontSize: 9, fontWeight: pw.FontWeight.bold),
+        textAlign: pw.TextAlign.center,
+      ),
+    );
+  }
+
+  pw.Widget _invoiceTitle() => pw.Column(children: [
+        pw.Text('TAX INVOICE',
+            style: pw.TextStyle(fontSize: 9, fontWeight: pw.FontWeight.bold)),
+        pw.SizedBox(height: 1),
+        pw.Text('xxxxxx Original for Recipient xxxxxx',
+            style: const pw.TextStyle(fontSize: 6)),
       ]);
 
   pw.Widget _meta(SaleTransaction txn) {
     final c = txn.customer;
-    return pw.Column(children: [
+    return pw.Column(
-      _row('Invoice', txn.invoiceNumber),
+      crossAxisAlignment: pw.CrossAxisAlignment.start,
-      _row('Date', Formatters.receiptStamp(txn.createdAt)),
+      children: [
-      _row('Cashier', txn.cashierName),
+        pw.SizedBox(height: 2),
-      _row('Terminal', txn.terminalId),
+        _line('Place of Supply & State Code: '
-      _row('Customer', c == null ? 'Walk-in' : c.name),
+            '${AppConstants.stateCode} ${AppConstants.stateName}'),
-      if (c != null) _row('Mobile', Formatters.mobile(c.mobile)),
+        // URD = unregistered dealer, the correct marking for retail walk-ins.
-    ]);
+        _line('Customer Type: ${c == null ? 'URD' : 'REG'}'),
+        _split(
+          'Date:${Formatters.receiptStamp(txn.createdAt)}',
+          'Bill No:${txn.invoiceNumber.split('-').last}',
+        ),
+        _split(
+          'Store:${AppConstants.storeCode}  Cashier:${txn.cashierName}',
+          'Pos No:${AppConstants.posNumber}',
+        ),
+        if (c != null) _line('Customer: ${c.name}  ${c.mobile}'),
+      ],
+    );
   }
 
-  pw.Widget _itemsTable(SaleTransaction txn) {
+  pw.Widget _itemsBySlab(List<_Slab> slabs) {
     return pw.Column(
       crossAxisAlignment: pw.CrossAxisAlignment.stretch,
       children: [
         pw.Row(children: [
-          pw.Expanded(flex: 5, child: _th('Item')),
+          pw.Expanded(flex: 12, child: _th('HSN')),
-          pw.Expanded(flex: 2, child: _th('Qty', align: pw.TextAlign.center)),
+          pw.Expanded(flex: 34, child: _th('Item Description')),
-          pw.Expanded(flex: 3, child: _th('Rate', align: pw.TextAlign.right)),
+          pw.Expanded(flex: 16, child: _th('Net Price', right: true)),
-          pw.Expanded(flex: 3, child: _th('Amt', align: pw.TextAlign.right)),
+          pw.Expanded(flex: 8, child: _th('Qty', right: true)),
+          pw.Expanded(flex: 18, child: _th('Value', right: true)),
         ]),
         pw.SizedBox(height: 2),
-        ...txn.cart.lines.map((line) => pw.Padding(
+        for (final slab in slabs) ...[
-              padding: const pw.EdgeInsets.symmetric(vertical: 1.5),
+          pw.Padding(
-              child: pw.Column(children: [
+            padding: const pw.EdgeInsets.only(top: 3, bottom: 1),
-                pw.Row(children: [
+            child: pw.Text(
-                  pw.Expanded(flex: 5, child: _td(line.product.name)),
+              '${slab.index}) CGST @ ${slab.halfPercent}  '
-                  pw.Expanded(
+              'SGST @ ${slab.halfPercent}',
-                    flex: 2,
+              style: pw.TextStyle(fontSize: 7, fontWeight: pw.FontWeight.bold),
-                    child: _td(
+            ),
-                      _qty(line.quantity),
+          ),
-                      align: pw.TextAlign.center,
+          for (final line in slab.lines)
-                    ),
+            pw.Padding(
-                  ),
+              padding: const pw.EdgeInsets.symmetric(vertical: 0.6),
-                  pw.Expanded(
+              child: pw.Row(children: [
-                    flex: 3,
+                pw.Expanded(
-                    child: _td(
+                  flex: 12,
-                      line.product.price.toStringAsFixed(2),
+                  child: _td(line.product.hsnCode ?? '-', size: 6.5),
-                      align: pw.TextAlign.right,
+                ),
-                    ),
+                pw.Expanded(
-                  ),
+                  flex: 34,
-                  pw.Expanded(
+                  child: _td(_description(line), size: 6.5),
-                    flex: 3,
+                ),
-                    child: _td(
+                pw.Expanded(
-                      line.payable.toStringAsFixed(2),
+                  flex: 16,
-                      align: pw.TextAlign.right,
+                  child: _td(line.product.price.toStringAsFixed(2),
-                    ),
+                      right: true, size: 6.5),
-                  ),
+                ),
-                ]),
+                pw.Expanded(
-                if (line.discount.isActive)
+                  flex: 8,
-                  pw.Row(children: [
+                  child: _td(_qty(line.quantity), right: true, size: 6.5),
-                    pw.Expanded(
+                ),
-                      child: _td(
+                pw.Expanded(
-                        '   ${line.discount.label}  '
+                  flex: 18,
-                        '-${line.discountAmount.toStringAsFixed(2)}',
+                  child: _td(line.payable.toStringAsFixed(2),
-                        size: 6.5,
+                      right: true, size: 6.5),
-                      ),
+                ),
-                    ),
-                  ]),
               ]),
-            )),
+            ),
+        ],
       ],
     );
   }
 
   pw.Widget _totals(SaleTransaction txn) {
     final cart = txn.cart;
+    final gross = _grossSalesValue(txn);
+    final discount = gross - cart.netAmount;
+
     return pw.Column(children: [
-      _row('Items', '${cart.lineCount}  (Qty ${_qty(cart.totalQuantity)})'),
+      _split(
-      _row('Subtotal', cart.subtotal.toStringAsFixed(2)),
+        'Items:${cart.lineCount}',
-      if (cart.membershipDiscountAmount > 0)
+        'Qty:${_qty(cart.totalQuantity)}    '
-        _row(
+            '${cart.netAmount.toStringAsFixed(2)}',
-          '${cart.customer!.tier.label} discount',
-          '-${cart.membershipDiscountAmount.toStringAsFixed(2)}',
-        ),
-      if (cart.manualBillDiscountAmount > 0)
-        _row('Discount', '-${cart.manualBillDiscountAmount.toStringAsFixed(2)}'),
-      if (cart.loyaltyRedemptionValue > 0)
-        _row(
-          'Points redeemed (${cart.pointsRedeemed})',
-          '-${cart.loyaltyRedemptionValue.toStringAsFixed(2)}',
-        ),
-      _row('Taxable value', cart.taxableAmount.toStringAsFixed(2)),
-      _row('CGST', cart.cgst.toStringAsFixed(2)),
-      _row('SGST', cart.sgst.toStringAsFixed(2)),
-      if (cart.roundOff != 0)
-        _row('Round off', cart.roundOff.toStringAsFixed(2)),
-      pw.SizedBox(height: 3),
-      pw.Row(
-        mainAxisAlignment: pw.MainAxisAlignment.spaceBetween,
-        children: [
-          pw.Text('TOTAL',
-              style: pw.TextStyle(fontSize: 12, fontWeight: pw.FontWeight.bold)),
-          pw.Text(
-            '${AppConstants.currencySymbol}${txn.total.toStringAsFixed(2)}',
-            style: pw.TextStyle(fontSize: 12, fontWeight: pw.FontWeight.bold),
-          ),
-        ],
       ),
-      if (cart.totalSavings > 0) ...[
+      pw.SizedBox(height: 2),
-        pw.SizedBox(height: 2),
+      _amount('Gross Sales Value', gross),
-        pw.Text(
+      if (discount > 0) _amount('Total Discount', discount),
-          'You saved ${AppConstants.currencySymbol}'
+      _amount('Net Sales Value (Inclusive of GST)', cart.netAmount),
-          '${cart.totalSavings.toStringAsFixed(2)} on this bill',
+      if (cart.roundOff != 0) _amount('Round Off', cart.roundOff),
-          style: pw.TextStyle(fontSize: 7.5, fontWeight: pw.FontWeight.bold),
+      _amount('Total Amount Paid', txn.total, bold: true),
-          textAlign: pw.TextAlign.center,
+      for (final p in txn.payments)
+        _amount(
+          p.method.label.toUpperCase() +
+              (p.reference != null ? ' ${p.reference}' : ''),
+          p.amount,
         ),
+      if (txn.changeDue > 0) _amount('Change Returned', txn.changeDue),
+      pw.SizedBox(height: 1),
+      pw.Text('(AMOUNT INCLUSIVE OF APPLICABLE TAXES)',
+          style: const pw.TextStyle(fontSize: 6)),
+    ]);
+  }
+
+  pw.Widget _gstBreakup(SaleTransaction txn, List<_Slab> slabs) {
+    return pw.Column(children: [
+      pw.Text('------GST Breakup Details------ Amount (INR)',
+          style: const pw.TextStyle(fontSize: 6.5)),
+      pw.SizedBox(height: 3),
+      pw.Row(children: [
+        pw.Expanded(flex: 10, child: _th('GST\nIND', size: 6)),
+        pw.Expanded(flex: 20, child: _th('Taxable\nAmount', right: true, size: 6)),
+        pw.Expanded(flex: 16, child: _th('CGST', right: true, size: 6)),
+        pw.Expanded(flex: 16, child: _th('SGST', right: true, size: 6)),
+        pw.Expanded(flex: 14, child: _th('CESS', right: true, size: 6)),
+        pw.Expanded(flex: 20, child: _th('Total\nAmount', right: true, size: 6)),
+      ]),
+      pw.SizedBox(height: 2),
+      for (final s in slabs)
+        pw.Padding(
+          padding: const pw.EdgeInsets.symmetric(vertical: 0.8),
+          child: pw.Row(children: [
+            pw.Expanded(flex: 10, child: _td('${s.index}', size: 6.5)),
+            pw.Expanded(
+                flex: 20,
+                child: _td(s.taxable.toStringAsFixed(2),
+                    right: true, size: 6.5)),
+            pw.Expanded(
+                flex: 16,
+                child: _td(s.cgst.toStringAsFixed(2), right: true, size: 6.5)),
+            pw.Expanded(
+                flex: 16,
+                child: _td(s.sgst.toStringAsFixed(2), right: true, size: 6.5)),
+            pw.Expanded(flex: 14, child: _td('0.00', right: true, size: 6.5)),
+            pw.Expanded(
+                flex: 20,
+                child:
+                    _td(s.total.toStringAsFixed(2), right: true, size: 6.5)),
+          ]),
+        ),
+      pw.Divider(height: 4, borderStyle: pw.BorderStyle.dashed),
+      pw.Row(children: [
+        pw.Expanded(flex: 10, child: _th('Total', size: 6.5)),
+        pw.Expanded(
+            flex: 20,
+            child: _th(
+                slabs.fold(0.0, (a, s) => a + s.taxable).toStringAsFixed(2),
+                right: true,
+                size: 6.5)),
+        pw.Expanded(
+            flex: 16,
+            child: _th(slabs.fold(0.0, (a, s) => a + s.cgst).toStringAsFixed(2),
+                right: true, size: 6.5)),
+        pw.Expanded(
+            flex: 16,
+            child: _th(slabs.fold(0.0, (a, s) => a + s.sgst).toStringAsFixed(2),
+                right: true, size: 6.5)),
+        pw.Expanded(flex: 14, child: _th('0.00', right: true, size: 6.5)),
+        pw.Expanded(
+            flex: 20,
+            child: _th(
+                slabs.fold(0.0, (a, s) => a + s.total).toStringAsFixed(2),
+                right: true,
+                size: 6.5)),
+      ]),
+    ]);
+  }
+
+  pw.Widget _references(SaleTransaction txn) {
+    final c = txn.customer;
+    return pw.Column(
+      crossAxisAlignment: pw.CrossAxisAlignment.start,
+      children: [
+        _line('TaxInvoice# ${txn.invoiceNumber}'),
+        _line('PaymentRefNo# ${txn.id.replaceAll('-', '').substring(0, 16)}'),
+        if (c != null)
+          _line('Loyalty Pts: earned ${txn.pointsEarned}'
+              '${txn.pointsRedeemed > 0 ? ', used ${txn.pointsRedeemed}' : ''}'
+              '  Bal: ${c.loyaltyPoints - txn.pointsRedeemed + txn.pointsEarned}'),
+        _line('Terms & Conditions Apply'),
       ],
-    ]);
+    );
-  }
-
-  pw.Widget _taxSummary(SaleTransaction txn) {
-    final breakdown = txn.cart.taxBreakdown.entries
-        .where((e) => e.value > 0)
-        .toList()
-      ..sort((a, b) => a.key.compareTo(b.key));
-
-    if (breakdown.isEmpty) {
-      return _td('All items zero-rated', size: 7);
-    }
-
-    return pw.Column(children: [
-      _th('GST Summary'),
-      ...breakdown.map((e) => _row(
-            'GST @ ${(e.key * 100).toStringAsFixed(0)}%',
-            e.value.toStringAsFixed(2),
-            size: 7,
-          )),
-    ]);
-  }
-
-  pw.Widget _payments(SaleTransaction txn) => pw.Column(children: [
-        ...txn.payments.map((p) => _row(
-              p.method.label +
-                  (p.reference != null ? ' (${p.reference})' : ''),
-              p.amount.toStringAsFixed(2),
-            )),
-        if (txn.changeDue > 0)
-          _row('Change returned', txn.changeDue.toStringAsFixed(2)),
-      ]);
-
-  pw.Widget _loyalty(SaleTransaction txn) {
-    final c = txn.customer!;
-    final balance = c.loyaltyPoints - txn.pointsRedeemed + txn.pointsEarned;
-    return pw.Column(children: [
-      _row('Points earned', '+${txn.pointsEarned}'),
-      if (txn.pointsRedeemed > 0)
-        _row('Points redeemed', '-${txn.pointsRedeemed}'),
-      _row('Points balance', '$balance'),
-      _row('Membership', c.tier.label),
-    ]);
   }
 
   pw.Widget _footer(SaleTransaction txn) => pw.Column(children: [
         pw.BarcodeWidget(
           barcode: pw.Barcode.code128(),
           data: txn.invoiceNumber,
-          width: 140,
+          width: 150,
-          height: 34,
+          height: 32,
           drawText: false,
         ),
-        pw.SizedBox(height: 4),
+        pw.SizedBox(height: 2),
-        pw.Text(txn.invoiceNumber, style: const pw.TextStyle(fontSize: 7)),
+        pw.Text(txn.invoiceNumber, style: const pw.TextStyle(fontSize: 6.5)),
-        pw.SizedBox(height: 4),
+        pw.SizedBox(height: 5),
-        pw.Text('Thank you for shopping with us!',
+        pw.Text(
-            style: pw.TextStyle(fontSize: 8, fontWeight: pw.FontWeight.bold)),
+          'I/We hereby certify that food/foods mentioned in this invoice '
-        pw.Text('Goods once sold are exchangeable within 7 days with this bill.',
+          'is/are warranted to be of the nature and quality which it/these '
-            style: const pw.TextStyle(fontSize: 6),
+          'purports/purported to be.',
+          style: const pw.TextStyle(fontSize: 5.5),
+          textAlign: pw.TextAlign.center,
+        ),
+        pw.SizedBox(height: 3),
+        pw.Text('* Thank You for Shopping with us *',
+            style: pw.TextStyle(fontSize: 7, fontWeight: pw.FontWeight.bold)),
+        pw.Text('Goods once sold are exchangeable within 7 days with this bill',
+            style: const pw.TextStyle(fontSize: 5.5),
             textAlign: pw.TextAlign.center),
         pw.SizedBox(height: 2),
-        pw.Text('Powered by Nearle POS', style: const pw.TextStyle(fontSize: 6)),
+        pw.Text('Powered by Nearle POS',
+            style: const pw.TextStyle(fontSize: 5.5)),
       ]);
 
   // -------------------------------------------------------------- Helpers
+  /// Pre-discount value, using printed MRP where one is known.
+  static double _grossSalesValue(SaleTransaction txn) => txn.cart.lines
+      .fold(0.0, (s, l) => s + (l.product.mrp ?? l.product.price) * l.quantity);
+
+  String _description(CartLine line) => line.product.name.toUpperCase();
+
   String _qty(double q) =>
       q % 1 == 0 ? q.toStringAsFixed(0) : q.toStringAsFixed(3);
 
-  pw.Widget _divider() => pw.Padding(
+  pw.Widget _rule() => pw.Padding(
         padding: const pw.EdgeInsets.symmetric(vertical: 3),
         child: pw.Divider(height: 0.5, borderStyle: pw.BorderStyle.dashed),
       );
 
-  pw.Widget _th(String text, {pw.TextAlign align = pw.TextAlign.left}) =>
+  pw.Widget _line(String text) => pw.Padding(
-      pw.Text(text,
+        padding: const pw.EdgeInsets.symmetric(vertical: 0.5),
-          textAlign: align,
+        child: pw.Text(text, style: const pw.TextStyle(fontSize: 6.5)),
-          style: pw.TextStyle(fontSize: 7.5, fontWeight: pw.FontWeight.bold));
+      );
 
-  pw.Widget _td(String text,
+  pw.Widget _split(String left, String right) => pw.Padding(
-          {pw.TextAlign align = pw.TextAlign.left, double size = 7.5}) =>
+        padding: const pw.EdgeInsets.symmetric(vertical: 0.5),
-      pw.Text(text, textAlign: align, style: pw.TextStyle(fontSize: size));
-
-  pw.Widget _row(String label, String value, {double size = 7.5}) => pw.Padding(
-        padding: const pw.EdgeInsets.symmetric(vertical: 0.8),
         child: pw.Row(
           mainAxisAlignment: pw.MainAxisAlignment.spaceBetween,
           children: [
-            pw.Text(label, style: pw.TextStyle(fontSize: size)),
+            pw.Text(left, style: const pw.TextStyle(fontSize: 6.5)),
-            pw.Text(value, style: pw.TextStyle(fontSize: size)),
+            pw.Text(right, style: const pw.TextStyle(fontSize: 6.5)),
           ],
         ),
       );
 
+  pw.Widget _amount(String label, double value, {bool bold = false}) =>
+      pw.Padding(
+        padding: const pw.EdgeInsets.symmetric(vertical: 0.6),
+        child: pw.Row(
+          mainAxisAlignment: pw.MainAxisAlignment.spaceBetween,
+          children: [
+            pw.Text(label,
+                style: pw.TextStyle(
+                  fontSize: 6.8,
+                  fontWeight: bold ? pw.FontWeight.bold : pw.FontWeight.normal,
+                )),
+            pw.Text(value.toStringAsFixed(2),
+                style: pw.TextStyle(
+                  fontSize: 6.8,
+                  fontWeight: bold ? pw.FontWeight.bold : pw.FontWeight.normal,
+                )),
+          ],
+        ),
+      );
+
+  pw.Widget _th(String text, {bool right = false, double size = 6.8}) =>
+      pw.Text(text,
+          textAlign: right ? pw.TextAlign.right : pw.TextAlign.left,
+          style: pw.TextStyle(fontSize: size, fontWeight: pw.FontWeight.bold));
+
+  pw.Widget _td(String text, {bool right = false, double size = 6.8}) =>
+      pw.Text(text,
+          maxLines: 1,
+          overflow: pw.TextOverflow.clip,
+          textAlign: right ? pw.TextAlign.right : pw.TextAlign.left,
+          style: pw.TextStyle(fontSize: size));
+
   // --------------------------------------------------------- Printing / IO
-  /// Silent print to the default roll printer — no OS dialog, so the cashier
+  /// Opens the system print preview.
-  /// is never blocked between sales.
+  ///
-  Future<bool> printDirect(SaleTransaction txn) async {
+  /// This is the on-terminal path: it renders the receipt on screen and works
+  /// with no printer attached. When a roll printer is wired up, switch the
+  /// receipt screen to [printDirect] and this becomes the fallback.
+  Future<void> printPreview(SaleTransaction txn) async {
+    final bytes = await build(txn);
+    await Printing.layoutPdf(
+      onLayout: (_) async => bytes,
+      name: txn.invoiceNumber,
+    );
+  }
+
+  /// Printers the operating system can see.
+  ///
+  /// A USB or network thermal printer shows up here once its driver is
+  /// installed — the terminal does not talk to the hardware itself.
+  Future<List<Printer>> availablePrinters() async {
     try {
+      return await Printing.listPrinters();
+    } catch (e) {
+      debugPrint('Printer discovery failed: $e');
+      return const [];
+    }
+  }
+
+  /// Silent print with no OS dialog, so the cashier is never blocked.
+  ///
+  /// [printerUrl] is the value saved from Settings. When it is null or the
+  /// printer has gone away, this falls back to the system default; when there
+  /// is no printer at all it returns false so the caller can show the preview
+  /// instead of pretending the bill was printed.
+  Future<bool> printDirect(
+    SaleTransaction txn, {
+    String? printerUrl,
+  }) async {
+    try {
+      final printers = await availablePrinters();
+      if (printers.isEmpty) return false;
+
+      final target = printers.where((p) => p.url == printerUrl).firstOrNull ??
+          printers.where((p) => p.isDefault).firstOrNull ??
+          printers.first;
+
       final bytes = await build(txn);
-      final printers = await Printing.listPrinters();
-      final target = printers.where((p) => p.isDefault).firstOrNull ??
-          (printers.isNotEmpty ? printers.first : null);
-
-      if (target == null) return false;
-
       return await Printing.directPrintPdf(
         printer: target,
         onLayout: (_) async => bytes,
@@ -312,24 +470,187 @@ class ReceiptService {
     }
   }
 
-  /// Falls back to the system print preview.
+  /// Sends a one-page test slip to confirm the printer is wired up.
-  Future<void> printWithDialog(SaleTransaction txn) async {
+  Future<bool> printTestPage({String? printerUrl}) async {
-    final bytes = await build(txn);
+    try {
-    await Printing.layoutPdf(
+      final printers = await availablePrinters();
-      onLayout: (_) async => bytes,
+      if (printers.isEmpty) return false;
-      name: txn.invoiceNumber,
+
-    );
+      final target = printers.where((p) => p.url == printerUrl).firstOrNull ??
+          printers.first;
+
+      final doc = pw.Document();
+      final font = await PdfGoogleFonts.robotoMonoRegular();
+      doc.addPage(
+        pw.Page(
+          pageFormat: PdfPageFormat(
+            _rollWidth,
+            double.infinity,
+            marginAll: 5 * PdfPageFormat.mm,
+          ),
+          theme: pw.ThemeData.withFont(base: font),
+          build: (_) => pw.Column(children: [
+            pw.Text(AppConstants.storeName.toUpperCase(),
+                style: pw.TextStyle(fontSize: 14, fontWeight: pw.FontWeight.bold)),
+            pw.SizedBox(height: 6),
+            pw.Text('PRINTER TEST', style: const pw.TextStyle(fontSize: 10)),
+            pw.SizedBox(height: 4),
+            pw.Text(target.name, style: const pw.TextStyle(fontSize: 7)),
+            pw.Text(Formatters.dateTime(DateTime.now()),
+                style: const pw.TextStyle(fontSize: 7)),
+            pw.SizedBox(height: 6),
+            pw.Text('1234567890 ABCDEFGHIJ',
+                style: const pw.TextStyle(fontSize: 8)),
+            pw.Text('₹ 1,234.56', style: const pw.TextStyle(fontSize: 8)),
+            pw.SizedBox(height: 6),
+            pw.BarcodeWidget(
+              barcode: pw.Barcode.code128(),
+              data: 'NEARLE-TEST',
+              width: 140,
+              height: 30,
+              drawText: false,
+            ),
+          ]),
+        ),
+      );
+
+      return await Printing.directPrintPdf(
+        printer: target,
+        onLayout: (_) async => doc.save(),
+        name: 'Nearle printer test',
+      );
+    } catch (e) {
+      debugPrint('Test print failed: $e');
+      return false;
+    }
   }
 
-  Future<void> share(SaleTransaction txn) async {
+  /// Shares the receipt PDF through the OS share sheet.
+  Future<void> sharePdf(SaleTransaction txn) async {
     final bytes = await build(txn);
     await Printing.sharePdf(bytes: bytes, filename: '${txn.invoiceNumber}.pdf');
   }
 
-  /// Opens the cash drawer via the ESC/POS kick pulse on pin 2.
+  /// Opens WhatsApp with the bill addressed to the customer's number.
-  Future<void> openCashDrawer() async {
+  ///
-    // ESC p m t1 t2 — sent to the receipt printer's serial passthrough.
+  /// WhatsApp cannot accept an attachment through a deep link, so the bill is
-    // Wired up here as a no-op placeholder for the concrete driver.
+  /// sent as formatted text. Returns false when there is no number to send to
-    debugPrint('Cash drawer kick: ESC p 0 25 250');
+  /// or WhatsApp is not installed.
+  Future<bool> sendToWhatsApp(SaleTransaction txn) async {
+    final mobile = txn.customer?.mobile.replaceAll(RegExp(r'\D'), '');
+    if (mobile == null || mobile.length < 10) return false;
+
+    final uri = Uri.parse(
+      'https://wa.me/91$mobile?text=${Uri.encodeComponent(whatsAppText(txn))}',
+    );
+
+    try {
+      return await launchUrl(uri, mode: LaunchMode.externalApplication);
+    } catch (e) {
+      debugPrint('WhatsApp launch failed: $e');
+      return false;
+    }
   }
+
+  /// Plain-text bill for messaging.
+  String whatsAppText(SaleTransaction txn) {
+    final cart = txn.cart;
+    final b = StringBuffer()
+      ..writeln('*${AppConstants.storeName}*')
+      ..writeln(AppConstants.storeAddress)
+      ..writeln('GSTIN: ${AppConstants.storeGstin}')
+      ..writeln()
+      ..writeln('Invoice: ${txn.invoiceNumber}')
+      ..writeln('Date: ${Formatters.dateTime(txn.createdAt)}')
+      ..writeln()
+      ..writeln('--------------------');
+
+    for (final line in cart.lines) {
+      final qty = line.quantity % 1 == 0
+          ? line.quantity.toStringAsFixed(0)
+          : line.quantity.toStringAsFixed(2);
+      b.writeln('$qty x ${line.product.name}'
+          '  ${Formatters.money(line.payable)}');
+    }
+
+    b
+      ..writeln('--------------------')
+      ..writeln('Subtotal: ${Formatters.money(cart.subtotal)}');
+
+    if (cart.billDiscountTotal > 0) {
+      b.writeln('Discount: -${Formatters.money(cart.billDiscountTotal)}');
+    }
+
+    b
+      ..writeln('GST: ${Formatters.money(cart.taxAmount)}')
+      ..writeln('*TOTAL: ${Formatters.money(txn.total)}*')
+      ..writeln()
+      ..writeln('Paid by ${txn.paymentSummary}');
+
+    if (txn.pointsEarned > 0) {
+      b.writeln('Points earned: +${txn.pointsEarned}');
+    }
+
+    b
+      ..writeln()
+      ..writeln('Thank you for shopping with us!');
+
+    return b.toString();
+  }
+
+  /// ESC/POS drawer kick: `ESC p m t1 t2` on pin 2.
+  ///
+  /// Most drawers are wired to the printer's RJ11 port and open when the
+  /// printer receives this. It cannot be sent through the PDF pipeline — a
+  /// PDF is rendered by the driver, not passed through as bytes — so this
+  /// needs a raw channel to the printer.
+  ///
+  /// On desktop with a driver-installed printer there is no raw path from
+  /// Flutter, so this stays a no-op. Wire it up when you move to ESC/POS:
+  /// send [drawerKickCommand] over the same socket or Bluetooth link that
+  /// carries the receipt.
+  Future<void> openCashDrawer() async {
+    debugPrint(
+      'Cash drawer kick requested — needs a raw ESC/POS channel, '
+      'not the PDF driver. Command: ${drawerKickCommand.join(' ')}',
+    );
+  }
+
+  /// `ESC p 0 25 250` — pin 2, 50ms on, 500ms off.
+  static const List<int> drawerKickCommand = [27, 112, 0, 25, 250];
+}
+
+/// One GST rate's slice of a bill.
+class _Slab {
+  _Slab({
+    required this.index,
+    required this.rate,
+    required this.lines,
+    required this.factor,
+  });
+
+  /// 1-based, printed both above the item group and in the breakup table.
+  final int index;
+
+  final double rate;
+  final List<CartLine> lines;
+
+  /// Share of the bill left after bill-level discounts.
+  final double factor;
+
+  /// e.g. "2.50%" — half the slab, since CGST and SGST each take half.
+  String get halfPercent => '${(rate * 100 / 2).toStringAsFixed(2)}%';
+
+  /// GST-inclusive value charged for this slab.
+  double get total =>
+      lines.fold(0.0, (s, l) => s + l.payable * factor).asMoney;
+
+  double get taxAmount =>
+      lines.fold(0.0, (s, l) => s + l.taxAmount * factor).asMoney;
+
+  double get taxable => (total - taxAmount).asMoney;
+
+  double get cgst => (taxAmount / 2).asMoney;
+
+  double get sgst => (taxAmount - cgst).asMoney;
 }

lib/data/datasources/remote_catalogue_source.dart

@@ -36,15 +36,19 @@ class CatalogueSyncException implements Exception {
 /// The real implementation would issue an HTTP request; the contract is the
 /// same, so only this class changes.
 class RemoteCatalogueSource {
-  RemoteCatalogueSource() {
+  RemoteCatalogueSource({required this.isOffline}) {
     LocalStore.registerSeed(
       products: SeedData.products,
       customers: SeedData.customers,
     );
   }
 
-  /// Flipped from Settings to exercise the offline path.
+  /// Reads the Settings switch on every call.
-  bool simulateOffline = false;
+  ///
+  /// Deliberately a callback rather than a stored bool: a copied flag can fall
+  /// out of step with the switch, which makes the terminal behave as offline
+  /// while showing that it is not.
+  final bool Function() isOffline;
 
   /// Streams progress so the import screen can show a real bar rather than an
   /// indeterminate spinner.
@@ -62,10 +66,10 @@ class RemoteCatalogueSource {
     for (final (progress, stage) in stages) {
       await Future<void>.delayed(const Duration(milliseconds: 320));
 
-      if (simulateOffline) {
+      if (isOffline()) {
         throw const CatalogueSyncException(
-          'No connection to the catalogue server. '
+          'Simulate offline is ON in Settings, so the catalogue pull was '
-          'Check the network and try again.',
+          'failed on purpose. Turn it off to import.',
         );
       }
 
@@ -83,9 +87,9 @@ class RemoteCatalogueSource {
 
 /// Stands in for the back-office order intake API.
 class RemoteOrderSink {
-  RemoteOrderSink();
+  RemoteOrderSink({required this.isOffline});
 
-  bool simulateOffline = false;
+  final bool Function() isOffline;
 
   /// Uploads a batch of orders and returns the ids the server accepted.
   ///
@@ -96,10 +100,10 @@ class RemoteOrderSink {
       Duration(milliseconds: 400 + orders.length * 60),
     );
 
-    if (simulateOffline) {
+    if (isOffline()) {
       throw const CatalogueSyncException(
-        'Could not reach the order server. Every bill is still stored on '
+        'Simulate offline is ON in Settings, so the upload was failed on '
-        'this terminal and will upload on the next attempt.',
+        'purpose. Every bill is still stored on this terminal.',
       );
     }
 

lib/data/datasources/seed_data.dart

@@ -22,6 +22,7 @@ class SeedData {
           emoji: '🥛',
           unit: UnitOfMeasure.litre,
           gstRate: 0.05,
+          hsnCode: '0401',
           brand: 'Amul',
         ),
         Product(
@@ -35,6 +36,7 @@ class SeedData {
           stock: 30,
           emoji: '🧈',
           gstRate: 0.12,
+          hsnCode: '0405',
           brand: 'Amul',
         ),
         Product(
@@ -48,6 +50,7 @@ class SeedData {
           stock: 40,
           emoji: '🥣',
           gstRate: 0.05,
+          hsnCode: '0403',
           brand: 'Nandini',
         ),
         Product(
@@ -60,6 +63,7 @@ class SeedData {
           stock: 20,
           emoji: '🧀',
           gstRate: 0.05,
+          hsnCode: '0406',
           brand: 'Milky Mist',
         ),
         Product(
@@ -73,6 +77,7 @@ class SeedData {
           stock: 25,
           emoji: '🧀',
           gstRate: 0.12,
+          hsnCode: '0406',
           brand: 'Britannia',
         ),
 
@@ -89,6 +94,7 @@ class SeedData {
           emoji: '🍚',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0.05,
+          hsnCode: '1006',
           brand: 'India Gate',
         ),
         Product(
@@ -103,6 +109,7 @@ class SeedData {
           emoji: '🛢️',
           unit: UnitOfMeasure.litre,
           gstRate: 0.05,
+          hsnCode: '1507',
           brand: 'Fortune',
         ),
         Product(
@@ -115,6 +122,7 @@ class SeedData {
           stock: 45,
           emoji: '🫘',
           gstRate: 0.05,
+          hsnCode: '0713',
           brand: 'Tata Sampann',
         ),
         Product(
@@ -129,6 +137,7 @@ class SeedData {
           emoji: '🌾',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0.05,
+          hsnCode: '1101',
           brand: 'Aashirvaad',
         ),
         Product(
@@ -142,6 +151,7 @@ class SeedData {
           emoji: '🍬',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0.05,
+          hsnCode: '1701',
         ),
         Product(
           id: 'p015',
@@ -153,6 +163,7 @@ class SeedData {
           stock: 120,
           emoji: '🍜',
           gstRate: 0.12,
+          hsnCode: '1902',
           brand: 'Nestlé',
         ),
         Product(
@@ -166,6 +177,7 @@ class SeedData {
           emoji: '🧂',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0.05,
+          hsnCode: '2501',
           brand: 'Tata',
         ),
 
@@ -181,6 +193,7 @@ class SeedData {
           emoji: '🥤',
           unit: UnitOfMeasure.millilitre,
           gstRate: 0.28,
+          hsnCode: '2202',
           brand: 'Coca-Cola',
         ),
         Product(
@@ -193,6 +206,7 @@ class SeedData {
           stock: 100,
           emoji: '🥭',
           gstRate: 0.12,
+          hsnCode: '2202',
           brand: 'Parle Agro',
         ),
         Product(
@@ -206,6 +220,7 @@ class SeedData {
           emoji: '💧',
           unit: UnitOfMeasure.litre,
           gstRate: 0.18,
+          hsnCode: '2201',
           brand: 'Bisleri',
         ),
         Product(
@@ -218,6 +233,7 @@ class SeedData {
           stock: 40,
           emoji: '🔋',
           gstRate: 0.28,
+          hsnCode: '2202',
           brand: 'Red Bull',
         ),
         Product(
@@ -231,6 +247,7 @@ class SeedData {
           stock: 30,
           emoji: '☕',
           gstRate: 0.18,
+          hsnCode: '2101',
           brand: 'Bru',
         ),
 
@@ -245,6 +262,7 @@ class SeedData {
           stock: 90,
           emoji: '🍪',
           gstRate: 0.18,
+          hsnCode: '1905',
           brand: 'Parle',
         ),
         Product(
@@ -257,6 +275,7 @@ class SeedData {
           stock: 110,
           emoji: '🥔',
           gstRate: 0.18,
+          hsnCode: '2005',
           brand: "Lay's",
         ),
         Product(
@@ -269,6 +288,7 @@ class SeedData {
           stock: 75,
           emoji: '🍫',
           gstRate: 0.18,
+          hsnCode: '1806',
           brand: 'Cadbury',
         ),
         Product(
@@ -281,6 +301,7 @@ class SeedData {
           stock: 85,
           emoji: '🍪',
           gstRate: 0.18,
+          hsnCode: '1905',
           brand: 'Britannia',
         ),
         Product(
@@ -293,6 +314,7 @@ class SeedData {
           stock: 60,
           emoji: '🥜',
           gstRate: 0.12,
+          hsnCode: '2106',
           brand: 'Haldiram',
         ),
 
@@ -308,6 +330,7 @@ class SeedData {
           stock: 55,
           emoji: '🪥',
           gstRate: 0.18,
+          hsnCode: '3306',
           brand: 'Colgate',
         ),
         Product(
@@ -320,6 +343,7 @@ class SeedData {
           stock: 70,
           emoji: '🧼',
           gstRate: 0.18,
+          hsnCode: '3401',
           brand: 'Dove',
         ),
         Product(
@@ -333,6 +357,7 @@ class SeedData {
           stock: 25,
           emoji: '🧴',
           gstRate: 0.18,
+          hsnCode: '3305',
           brand: 'P&G',
         ),
         Product(
@@ -345,6 +370,7 @@ class SeedData {
           stock: 30,
           emoji: '🧴',
           gstRate: 0.18,
+          hsnCode: '3304',
           brand: 'Nivea',
         ),
 
@@ -361,6 +387,7 @@ class SeedData {
           emoji: '🧺',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0.18,
+          hsnCode: '3402',
           brand: 'Surf Excel',
         ),
         Product(
@@ -373,6 +400,7 @@ class SeedData {
           stock: 90,
           emoji: '🧽',
           gstRate: 0.18,
+          hsnCode: '3401',
           brand: 'Vim',
         ),
         Product(
@@ -385,6 +413,7 @@ class SeedData {
           stock: 40,
           emoji: '🧴',
           gstRate: 0.18,
+          hsnCode: '3402',
           brand: 'Harpic',
         ),
         Product(
@@ -397,6 +426,7 @@ class SeedData {
           stock: 35,
           emoji: '🗑️',
           gstRate: 0.18,
+          hsnCode: '3923',
         ),
 
         // ----------------------------------------------------------- Fruits
@@ -411,6 +441,7 @@ class SeedData {
           emoji: '🍌',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0,
+          hsnCode: '0803',
         ),
         Product(
           id: 'p061',
@@ -423,6 +454,7 @@ class SeedData {
           emoji: '🍎',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0,
+          hsnCode: '0808',
         ),
         Product(
           id: 'p062',
@@ -435,6 +467,7 @@ class SeedData {
           emoji: '🥭',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0,
+          hsnCode: '0804',
         ),
 
         // ------------------------------------------------------- Vegetables
@@ -449,6 +482,7 @@ class SeedData {
           emoji: '🍅',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0,
+          hsnCode: '0702',
         ),
         Product(
           id: 'p071',
@@ -461,6 +495,7 @@ class SeedData {
           emoji: '🧅',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0,
+          hsnCode: '0703',
         ),
         Product(
           id: 'p072',
@@ -473,6 +508,7 @@ class SeedData {
           emoji: '🥔',
           unit: UnitOfMeasure.kilogram,
           gstRate: 0,
+          hsnCode: '0701',
         ),
         Product(
           id: 'p073',
@@ -484,6 +520,7 @@ class SeedData {
           stock: 8,
           emoji: '🥕',
           gstRate: 0,
+          hsnCode: '0706',
         ),
       ];
 

lib/data/local/app_database.dart

@@ -1,5 +1,3 @@
-import 'dart:io';
-
 import 'package:flutter/foundation.dart';
 import 'package:path/path.dart' as p;
 import 'package:sqflite/sqflite.dart';
@@ -16,7 +14,7 @@ class AppDatabase {
   static final AppDatabase instance = AppDatabase._();
 
   static const String _fileName = 'nearle_pos.db';
-  static const int _version = 1;
+  static const int _version = 3;
 
   Database? _db;
 
@@ -37,7 +35,21 @@ class AppDatabase {
   Future<void> open({String? overridePath}) async {
     if (_db != null) return;
 
-    if (!kIsWeb && (Platform.isWindows || Platform.isLinux || Platform.isMacOS)) {
+    if (kIsWeb) {
+      // sqflite has no web implementation. Fail loudly here rather than
+      // letting databaseFactory throw something unreadable further down.
+      throw UnsupportedError(
+        'Nearle POS stores bills in SQLite, which has no web implementation. '
+        'Run the app on macOS, Windows, Linux or an Android tablet.',
+      );
+    }
+
+    const desktop = {
+      TargetPlatform.windows,
+      TargetPlatform.linux,
+      TargetPlatform.macOS,
+    };
+    if (desktop.contains(defaultTargetPlatform)) {
       sqfliteFfiInit();
       databaseFactory = databaseFactoryFfi;
     }
@@ -52,7 +64,12 @@ class AppDatabase {
         onConfigure: (db) => db.execute('PRAGMA foreign_keys = ON'),
         onCreate: (db, version) async => _createSchema(db),
         onUpgrade: (db, from, to) async {
-          // Single version so far; migrations land here as the schema grows.
+          if (from < 2) await db.execute(_createDayArchive);
+          if (from < 3) {
+            await db.execute(
+              'ALTER TABLE ${Tables.products} ADD COLUMN hsn_code TEXT',
+            );
+          }
         },
       ),
     );
@@ -84,6 +101,7 @@ class AppDatabase {
     for (final t in const [
       Tables.orderItems,
       Tables.orders,
+      Tables.dayArchive,
       Tables.products,
       Tables.customers,
       Tables.parkedBills,
@@ -111,6 +129,7 @@ class AppDatabase {
         image_url   TEXT,
         unit        TEXT    NOT NULL DEFAULT 'piece',
         gst_rate    REAL    NOT NULL DEFAULT 0.18,
+        hsn_code    TEXT,
         brand       TEXT,
         is_active   INTEGER NOT NULL DEFAULT 1,
         updated_at  INTEGER NOT NULL
@@ -232,6 +251,9 @@ class AppDatabase {
       )
     ''');
 
+    // ------------------------------------------------------------- archive
+    await db.execute(_createDayArchive);
+
     // ----------------------------------------------------------------- meta
     await db.execute('''
       CREATE TABLE ${Tables.meta} (
@@ -242,9 +264,34 @@ class AppDatabase {
   }
 }
 
+/// Running totals per business day.
+///
+/// Synced orders are deleted from the terminal, so their figures are folded in
+/// here first — otherwise "Bills Today" would collapse to zero the moment a
+/// mid-shift sync ran.
+const String _createDayArchive = '''
+  CREATE TABLE day_archive (
+    business_date   TEXT PRIMARY KEY,
+    bill_count      INTEGER NOT NULL DEFAULT 0,
+    item_count      REAL    NOT NULL DEFAULT 0,
+    gross_sales     REAL    NOT NULL DEFAULT 0,
+    tax_collected   REAL    NOT NULL DEFAULT 0,
+    discount_given  REAL    NOT NULL DEFAULT 0,
+    round_off       REAL    NOT NULL DEFAULT 0,
+    points_issued   INTEGER NOT NULL DEFAULT 0,
+    points_redeemed INTEGER NOT NULL DEFAULT 0,
+    payments_json   TEXT    NOT NULL DEFAULT '{}',
+    first_bill_at   INTEGER,
+    last_bill_at    INTEGER,
+    synced_bills    INTEGER NOT NULL DEFAULT 0
+  )
+''';
+
 class Tables {
   const Tables._();
 
+  static const String dayArchive = 'day_archive';
+
   static const String products = 'products';
   static const String customers = 'customers';
   static const String orders = 'orders';
@@ -260,4 +307,11 @@ class MetaKeys {
   static const String lastImportAt = 'last_import_at';
   static const String catalogueRevision = 'catalogue_revision';
   static const String invoiceSequence = 'invoice_sequence';
+
+  /// Printer chosen in Settings. Stored as the printer's `url`, which is what
+  /// `Printing.directPrintPdf` needs to target it without a dialog.
+  static const String printerUrl = 'printer_url';
+  static const String printerName = 'printer_name';
+  static const String autoPrint = 'auto_print';
+  static const String openDrawer = 'open_cash_drawer';
 }

lib/data/local/catalogue_dao.dart

@@ -24,6 +24,7 @@ class CatalogueDao {
         'image_url': p.imageUrl,
         'unit': p.unit.name,
         'gst_rate': p.gstRate,
+        'hsn_code': p.hsnCode,
         'brand': p.brand,
         'is_active': p.isActive ? 1 : 0,
         'updated_at': DateTime.now().millisecondsSinceEpoch,
@@ -42,6 +43,7 @@ class CatalogueDao {
         imageUrl: r['image_url'] as String?,
         unit: UnitOfMeasure.values.byName((r['unit'] as String?) ?? 'piece'),
         gstRate: (r['gst_rate']! as num).toDouble(),
+        hsnCode: r['hsn_code'] as String?,
         brand: r['brand'] as String?,
         isActive: (r['is_active']! as int) == 1,
       );
@@ -125,27 +127,34 @@ class CatalogueDao {
 
   /// Writes the pulled catalogue in one transaction.
   ///
-  /// Stock already decremented by local sales is preserved for products that
+  /// The server's stock figure wins outright. Local sales have already been
-  /// survive the import, so re-importing mid-shift cannot resurrect sold units.
+  /// uploaded and deleted by the time a re-import happens, so the server count
+  /// is the corrected one — keeping the local number would double-count the
+  /// units that were sold.
   Future<void> replaceCatalogue({
     required List<Product> products,
     required List<Customer> customers,
   }) async {
     await _db.transaction((txn) async {
-      final existing = await txn.query(
+      final incoming = products.map((p) => p.id).toSet();
-        Tables.products,
+
-        columns: ['id', 'stock'],
+      // Products the server no longer lists are withdrawn from sale.
-      );
+      final existing = await txn.query(Tables.products, columns: ['id']);
-      final heldStock = {
+      final stale = existing
-        for (final r in existing) r['id']! as String: (r['stock']! as num).toDouble(),
+          .map((r) => r['id']! as String)
-      };
+          .where((id) => !incoming.contains(id))
+          .toList();
 
       final batch = txn.batch();
+
+      for (final id in stale) {
+        batch.delete(Tables.products, where: 'id = ?', whereArgs: [id]);
+      }
+
       for (final p in products) {
-        final held = heldStock[p.id];
         batch.insert(
           Tables.products,
-          productToRow(held == null ? p : p.copyWith(stock: held)),
+          productToRow(p),
           conflictAlgorithm: ConflictAlgorithm.replace,
         );
       }

lib/data/local/order_dao.dart

@@ -171,17 +171,111 @@ class OrderDao {
       );
 
   // ----------------------------------------------------------------- Sync
-  /// Flips accepted orders to `sync_status = 1`.
+  /// Folds accepted orders into the day archive, then deletes them.
-  Future<void> markSynced(List<String> orderIds) async {
+  ///
-    if (orderIds.isEmpty) return;
+  /// Once the server holds a bill the terminal has no reason to keep it, so
-    final now = DateTime.now().millisecondsSinceEpoch;
+  /// the rows go. Their figures are added to [Tables.dayArchive] first, so the
-    final placeholders = List.filled(orderIds.length, '?').join(',');
+  /// shift totals a cashier sees do not collapse after a mid-shift sync.
+  /// Both steps run in one transaction: if the delete fails the archive is
+  /// rolled back with it, and nothing is counted twice.
+  Future<void> archiveAndDelete(List<SaleTransaction> orders) async {
+    if (orders.isEmpty) return;
 
-    await _db.rawUpdate(
+    await _db.transaction((txn) async {
-      'UPDATE ${Tables.orders} SET sync_status = ?, synced_at = ?, '
+      final byDate = <String, List<SaleTransaction>>{};
-      'sync_error = NULL WHERE id IN ($placeholders)',
+      for (final o in orders) {
-      [synced, now, ...orderIds],
+        byDate.putIfAbsent(businessDateOf(o.createdAt), () => []).add(o);
+      }
+
+      for (final entry in byDate.entries) {
+        final date = entry.key;
+        final batchOrders = entry.value;
+
+        final prior = await txn.query(
+          Tables.dayArchive,
+          where: 'business_date = ?',
+          whereArgs: [date],
+          limit: 1,
+        );
+        final existing = prior.isEmpty ? null : prior.first;
+
+        final priorPayments = existing == null
+            ? <String, double>{}
+            : (jsonDecode(existing['payments_json']! as String)
+                    as Map<String, Object?>)
+                .map((k, v) => MapEntry(k, (v! as num).toDouble()));
+
+        for (final o in batchOrders) {
+          for (final p in o.payments) {
+            priorPayments[p.method.name] =
+                (priorPayments[p.method.name] ?? 0) + p.amount;
+          }
+        }
+
+        final firsts = batchOrders
+            .map((o) => o.createdAt.millisecondsSinceEpoch)
+            .toList()
+          ..sort();
+
+        await txn.insert(
+          Tables.dayArchive,
+          {
+            'business_date': date,
+            'bill_count':
+                ((existing?['bill_count'] as int?) ?? 0) + batchOrders.length,
+            'item_count': ((existing?['item_count'] as num?)?.toDouble() ?? 0) +
+                batchOrders.fold(0.0, (s, o) => s + o.cart.totalQuantity),
+            'gross_sales':
+                ((existing?['gross_sales'] as num?)?.toDouble() ?? 0) +
+                    batchOrders.fold(0.0, (s, o) => s + o.total),
+            'tax_collected':
+                ((existing?['tax_collected'] as num?)?.toDouble() ?? 0) +
+                    batchOrders.fold(0.0, (s, o) => s + o.cart.taxAmount),
+            'discount_given':
+                ((existing?['discount_given'] as num?)?.toDouble() ?? 0) +
+                    batchOrders.fold(
+                      0.0,
+                      (s, o) =>
+                          s +
+                          o.cart.billDiscountTotal +
+                          o.cart.lineDiscountTotal,
+                    ),
+            'round_off': ((existing?['round_off'] as num?)?.toDouble() ?? 0) +
+                batchOrders.fold(0.0, (s, o) => s + o.cart.roundOff),
+            'points_issued': ((existing?['points_issued'] as int?) ?? 0) +
+                batchOrders.fold(0, (s, o) => s + o.pointsEarned),
+            'points_redeemed': ((existing?['points_redeemed'] as int?) ?? 0) +
+                batchOrders.fold(0, (s, o) => s + o.pointsRedeemed),
+            'payments_json': jsonEncode(priorPayments),
+            'first_bill_at': existing?['first_bill_at'] ?? firsts.first,
+            'last_bill_at': firsts.last,
+            'synced_bills':
+                ((existing?['synced_bills'] as int?) ?? 0) + batchOrders.length,
+          },
+          conflictAlgorithm: ConflictAlgorithm.replace,
+        );
+      }
+
+      // order_items goes with it via ON DELETE CASCADE.
+      final ids = orders.map((o) => o.id).toList();
+      final placeholders = List.filled(ids.length, '?').join(',');
+      await txn.delete(
+        Tables.orders,
+        where: 'id IN ($placeholders)',
+        whereArgs: ids,
+      );
+    });
+  }
+
+  /// Archived figures for a business day, or null if nothing has synced yet.
+  Future<Map<String, Object?>?> dayArchive(DateTime day) async {
+    final rows = await _db.query(
+      Tables.dayArchive,
+      where: 'business_date = ?',
+      whereArgs: [businessDateOf(day)],
+      limit: 1,
     );
+    return rows.isEmpty ? null : rows.first;
   }
 
   /// Records a failed attempt. The rows stay at `sync_status = 0`.

lib/data/repositories/sync_repository_impl.dart

@@ -1,3 +1,5 @@
+import 'dart:convert';
+
 import 'package:uuid/uuid.dart';
 
 import '../../core/utils/formatters.dart';
@@ -99,14 +101,37 @@ class SyncRepositoryImpl implements SyncRepository {
     required String cashierName,
   }) async {
     final today = DateTime.now();
-    final orders = await _store.orders.forBusinessDate(today);
 
-    return ShiftReport.fromTransactions(
+    // Bills still held locally.
-      transactions: orders,
+    final live = ShiftReport.fromTransactions(
+      transactions: await _store.orders.forBusinessDate(today),
       businessDate: today,
       terminalId: terminalId,
       cashierName: cashierName,
     );
+
+    // Bills already uploaded and deleted survive only as archived totals.
+    final row = await _store.orders.dayArchive(today);
+    if (row == null) return live;
+
+    final payments = (jsonDecode(row['payments_json']! as String)
+            as Map<String, Object?>)
+        .map(
+          (k, v) => MapEntry(
+            PaymentMethod.values.byName(k),
+            (v! as num).toDouble(),
+          ),
+        );
+
+    final archived = ShiftReport.fromArchive(
+      row: row,
+      payments: payments,
+      businessDate: today,
+      terminalId: terminalId,
+      cashierName: cashierName,
+    );
+
+    return archived + live;
   }
 
   @override
@@ -152,10 +177,13 @@ class SyncRepositoryImpl implements SyncRepository {
         pending.map(_orderToPayload).toList(),
       );
 
-      onProgress?.call(0.85, 'Marking bills as synced…');
+      onProgress?.call(0.85, 'Clearing uploaded bills from this terminal…');
 
-      // Only what the server confirmed is flipped to 1.
+      // Only what the server confirmed is archived and removed. Anything it
-      await _store.orders.markSynced(accepted);
+      // did not acknowledge stays on disk.
+      final acceptedOrders =
+          pending.where((o) => accepted.contains(o.id)).toList();
+      await _store.orders.archiveAndDelete(acceptedOrders);
       await _store.refreshUnsyncedCount();
 
       final rejected = ids.where((id) => !accepted.contains(id)).toList();

lib/domain/entities/product.dart

@@ -51,6 +51,7 @@ class Product extends Equatable {
     this.imageUrl,
     this.unit = UnitOfMeasure.piece,
     this.gstRate = AppConstants.defaultGstRate,
+    this.hsnCode,
     this.brand,
     this.isActive = true,
   });
@@ -72,6 +73,11 @@ class Product extends Equatable {
   final String? imageUrl;
   final UnitOfMeasure unit;
   final double gstRate;
+
+  /// HSN/SAC code. Printed on the tax invoice — legally required on a GST
+  /// invoice above the turnover threshold. Blank when the catalogue omits it.
+  final String? hsnCode;
+
   final String? brand;
   final bool isActive;
 
@@ -124,6 +130,7 @@ class Product extends Equatable {
       imageUrl: imageUrl,
       unit: unit,
       gstRate: gstRate,
+      hsnCode: hsnCode,
       brand: brand,
       isActive: isActive ?? this.isActive,
     );

lib/domain/entities/shift_report.dart

@@ -124,6 +124,76 @@ class ShiftReport extends Equatable {
     );
   }
 
+  /// Rebuilds a report from an archived day row.
+  factory ShiftReport.fromArchive({
+    required Map<String, Object?> row,
+    required Map<PaymentMethod, double> payments,
+    required DateTime businessDate,
+    required String terminalId,
+    required String cashierName,
+  }) {
+    DateTime? at(Object? v) =>
+        v == null ? null : DateTime.fromMillisecondsSinceEpoch(v as int);
+
+    return ShiftReport(
+      businessDate: businessDate,
+      terminalId: terminalId,
+      cashierName: cashierName,
+      billCount: (row['bill_count'] as int?) ?? 0,
+      itemCount: (row['item_count'] as num?)?.toDouble() ?? 0,
+      grossSales: (row['gross_sales'] as num?)?.toDouble() ?? 0,
+      taxCollected: (row['tax_collected'] as num?)?.toDouble() ?? 0,
+      discountGiven: (row['discount_given'] as num?)?.toDouble() ?? 0,
+      roundOff: (row['round_off'] as num?)?.toDouble() ?? 0,
+      paymentBreakdown: payments,
+      loyaltyPointsIssued: (row['points_issued'] as int?) ?? 0,
+      loyaltyPointsRedeemed: (row['points_redeemed'] as int?) ?? 0,
+      firstBillAt: at(row['first_bill_at']),
+      lastBillAt: at(row['last_bill_at']),
+    );
+  }
+
+  /// Adds two reports for the same day.
+  ///
+  /// Needed because synced bills are deleted from the terminal: the day's true
+  /// figures are the archived totals plus whatever is still held locally.
+  ShiftReport operator +(ShiftReport other) {
+    final payments = <PaymentMethod, double>{...paymentBreakdown};
+    other.paymentBreakdown.forEach((k, v) {
+      payments[k] = ((payments[k] ?? 0) + v).asMoney;
+    });
+
+    DateTime? earliest(DateTime? a, DateTime? b) {
+      if (a == null) return b;
+      if (b == null) return a;
+      return a.isBefore(b) ? a : b;
+    }
+
+    DateTime? latest(DateTime? a, DateTime? b) {
+      if (a == null) return b;
+      if (b == null) return a;
+      return a.isAfter(b) ? a : b;
+    }
+
+    return ShiftReport(
+      businessDate: businessDate,
+      terminalId: terminalId,
+      cashierName: cashierName,
+      billCount: billCount + other.billCount,
+      itemCount: itemCount + other.itemCount,
+      grossSales: (grossSales + other.grossSales).asMoney,
+      taxCollected: (taxCollected + other.taxCollected).asMoney,
+      discountGiven: (discountGiven + other.discountGiven).asMoney,
+      roundOff: (roundOff + other.roundOff).asMoney,
+      paymentBreakdown: payments,
+      loyaltyPointsIssued: loyaltyPointsIssued + other.loyaltyPointsIssued,
+      loyaltyPointsRedeemed:
+          loyaltyPointsRedeemed + other.loyaltyPointsRedeemed,
+      firstBillAt: earliest(firstBillAt, other.firstBillAt),
+      lastBillAt: latest(lastBillAt, other.lastBillAt),
+    );
+  }
+
   /// The JSON body that would be sent to the back office.
   Map<String, Object?> toPayload() => {
         'business_date': businessDate.toIso8601String().substring(0, 10),

lib/main.dart

@@ -5,6 +5,8 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 
 import 'app/app.dart';
 import 'core/services/sound_service.dart';
+import 'core/theme/app_colors.dart';
+import 'core/theme/app_dimens.dart';
 import 'data/datasources/local_store.dart';
 
 Future<void> main() async {
@@ -12,10 +14,19 @@ Future<void> main() async {
 
   await _configureChrome();
 
-  // Opens SQLite and loads the catalogue into memory. Any bill written on a
+  // Startup work must never be able to prevent runApp from being reached.
-  // previous run is still on disk and still counted as unsynced.
+  // Awaiting it unguarded means one thrown exception leaves a blank window
-  await LocalStore.instance.init();
+  // with nothing on screen to explain why.
-  await SoundService.instance.preload();
+  try {
+    // Opens SQLite and loads the catalogue into memory. Bills written on a
+    // previous run are still on disk and still counted as unsynced.
+    await LocalStore.instance.init();
+    await SoundService.instance.preload();
+  } catch (error, stack) {
+    debugPrint('Startup failed: $error\n$stack');
+    runApp(_StartupFailureApp(error: error));
+    return;
+  }
 
   runApp(const ProviderScope(child: NearlePosApp()));
 }
@@ -37,3 +48,84 @@ Future<void> _configureChrome() async {
 
   await SystemChrome.setEnabledSystemUIMode(SystemUiMode.immersiveSticky);
 }
+
+/// Shown when the terminal cannot start.
+///
+/// A cashier staring at a white window has nothing to report to support, so
+/// the failure is put on screen verbatim.
+class _StartupFailureApp extends StatelessWidget {
+  const _StartupFailureApp({required this.error});
+
+  final Object error;
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      debugShowCheckedModeBanner: false,
+      home: Scaffold(
+        backgroundColor: AppColors.background,
+        body: Center(
+          child: SingleChildScrollView(
+            padding: const EdgeInsets.all(AppSpacing.xxl),
+            child: ConstrainedBox(
+              constraints: const BoxConstraints(maxWidth: 560),
+              child: Column(
+                mainAxisSize: MainAxisSize.min,
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Container(
+                    width: 56,
+                    height: 56,
+                    decoration: BoxDecoration(
+                      color: AppColors.dangerSurface,
+                      borderRadius: AppRadius.brMd,
+                    ),
+                    child: const Icon(Icons.error_outline_rounded,
+                        color: AppColors.danger, size: 28),
+                  ),
+                  const SizedBox(height: AppSpacing.xl),
+                  const Text(
+                    'Nearle POS could not start',
+                    style: TextStyle(
+                      fontSize: 22,
+                      fontWeight: FontWeight.w700,
+                      color: AppColors.textPrimary,
+                    ),
+                  ),
+                  const SizedBox(height: AppSpacing.sm),
+                  const Text(
+                    'The terminal failed while opening its local database.',
+                    style: TextStyle(
+                      fontSize: 14,
+                      color: AppColors.textSecondary,
+                      height: 1.5,
+                    ),
+                  ),
+                  const SizedBox(height: AppSpacing.xl),
+                  Container(
+                    width: double.infinity,
+                    padding: const EdgeInsets.all(AppSpacing.lg),
+                    decoration: BoxDecoration(
+                      color: AppColors.surface,
+                      borderRadius: AppRadius.brMd,
+                      border: Border.all(color: AppColors.border),
+                    ),
+                    child: SelectableText(
+                      '$error',
+                      style: const TextStyle(
+                        fontSize: 12.5,
+                        height: 1.6,
+                        fontFamily: 'monospace',
+                        color: AppColors.textPrimary,
+                      ),
+                    ),
+                  ),
+                ],
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/presentation/customer/widgets/customer_capture_sheet.dart

@@ -78,12 +78,13 @@ class _CustomerCaptureSheetState
     Navigator.of(context).pop();
   }
 
+  /// Saves with whatever was given. Both fields are optional: a bare number
+  /// is still worth keeping, because it is what the WhatsApp bill is sent to.
   Future<void> _quickRegister() async {
-    final name = _name.text.trim();
+    final typed = _name.text.trim();
-    if (name.length < 2) {
+    final name = typed.isEmpty
-      setState(() => _error = 'Enter a name to save this customer');
+        ? 'Customer ${_digits.substring(_digits.length - 4)}'
-      return;
+        : typed;
-    }
 
     setState(() {
       _saving = true;
@@ -320,8 +321,11 @@ class _CustomerCaptureSheetState
         _message(
           Icons.dialpad_rounded,
           AppColors.textTertiary,
-          'Key in a 10-digit mobile number. The lookup runs automatically.',
+          'Key in a 10-digit mobile number — the lookup runs automatically. '
+          'Both fields are optional.',
         ),
+        const SizedBox(height: AppSpacing.lg),
+        _nameField(),
         if (recent.isNotEmpty) ...[
           const SizedBox(height: AppSpacing.xl),
           const Align(
@@ -466,22 +470,11 @@ class _CustomerCaptureSheetState
           _message(
             Icons.person_search_rounded,
             AppColors.warning,
-            'Not registered yet. Add a name to save them, or carry on '
+            'New number. Add a name if you have it — the bill can be sent to '
-            'without.',
+            'this number on WhatsApp either way.',
           ),
           const SizedBox(height: AppSpacing.lg),
-          TextField(
+          _nameField(),
-            controller: _name,
-            textCapitalization: TextCapitalization.words,
-            enabled: !_saving,
-            onSubmitted: (_) => _quickRegister(),
-            inputFormatters: [LengthLimitingTextInputFormatter(60)],
-            decoration: const InputDecoration(
-              labelText: 'Customer name',
-              hintText: 'Full name',
-              prefixIcon: Icon(Icons.person_outline_rounded),
-            ),
-          ),
           if (_error != null) ...[
             const SizedBox(height: AppSpacing.sm),
             Text(
@@ -506,6 +499,19 @@ class _CustomerCaptureSheetState
         ],
       );
 
+  Widget _nameField() => TextField(
+        controller: _name,
+        textCapitalization: TextCapitalization.words,
+        enabled: !_saving,
+        onSubmitted: (_) => _quickRegister(),
+        inputFormatters: [LengthLimitingTextInputFormatter(60)],
+        decoration: const InputDecoration(
+          labelText: 'Customer name',
+          hintText: 'Optional',
+          prefixIcon: Icon(Icons.person_outline_rounded),
+        ),
+      );
+
   Widget _miniStat(String value, String label) => Column(
         crossAxisAlignment: CrossAxisAlignment.start,
         mainAxisSize: MainAxisSize.min,

lib/presentation/modules/providers/printer_settings.dart

@@ -0,0 +1,118 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:printing/printing.dart';
+
+import '../../../app/providers.dart';
+import '../../../data/local/app_database.dart';
+
+/// Hardware preferences for this terminal.
+///
+/// Persisted in `app_meta` rather than held in widget state, so the choice
+/// survives a restart — a cashier should not have to reselect the printer
+/// every morning.
+class PrinterSettings {
+  const PrinterSettings({
+    this.printerUrl,
+    this.printerName,
+    this.autoPrint = false,
+    this.openDrawer = true,
+  });
+
+  /// Target passed to `directPrintPdf`. Null means "use the system default".
+  final String? printerUrl;
+
+  /// Shown in Settings. Kept alongside the url because the url is opaque.
+  final String? printerName;
+
+  /// Print silently the moment a sale completes.
+  ///
+  /// Defaults to **off**: with no printer attached, auto-printing fails
+  /// invisibly and looks like a bug.
+  final bool autoPrint;
+
+  final bool openDrawer;
+
+  bool get hasPrinter => printerUrl != null;
+
+  PrinterSettings copyWith({
+    String? printerUrl,
+    String? printerName,
+    bool clearPrinter = false,
+    bool? autoPrint,
+    bool? openDrawer,
+  }) {
+    return PrinterSettings(
+      printerUrl: clearPrinter ? null : (printerUrl ?? this.printerUrl),
+      printerName: clearPrinter ? null : (printerName ?? this.printerName),
+      autoPrint: autoPrint ?? this.autoPrint,
+      openDrawer: openDrawer ?? this.openDrawer,
+    );
+  }
+}
+
+class PrinterSettingsController extends StateNotifier<PrinterSettings> {
+  PrinterSettingsController(this._ref) : super(const PrinterSettings()) {
+    _load();
+  }
+
+  final Ref _ref;
+
+  Future<void> _load() async {
+    final store = _ref.read(localStoreProvider);
+    if (!store.isReady) return;
+
+    final dao = store.catalogue;
+    state = PrinterSettings(
+      printerUrl: await dao.meta(MetaKeys.printerUrl),
+      printerName: await dao.meta(MetaKeys.printerName),
+      autoPrint: (await dao.meta(MetaKeys.autoPrint)) == '1',
+      openDrawer: (await dao.meta(MetaKeys.openDrawer)) != '0',
+    );
+  }
+
+  Future<void> selectPrinter(Printer? printer) async {
+    final dao = _ref.read(localStoreProvider).catalogue;
+
+    if (printer == null) {
+      await dao.setMeta(MetaKeys.printerUrl, '');
+      await dao.setMeta(MetaKeys.printerName, '');
+      state = state.copyWith(clearPrinter: true, autoPrint: false);
+      return;
+    }
+
+    await dao.setMeta(MetaKeys.printerUrl, printer.url);
+    await dao.setMeta(MetaKeys.printerName, printer.name);
+    state = state.copyWith(
+      printerUrl: printer.url,
+      printerName: printer.name,
+    );
+  }
+
+  Future<void> setAutoPrint(bool value) async {
+    // Auto-print with nothing selected would fail silently on every sale.
+    if (value && !state.hasPrinter) return;
+
+    await _ref
+        .read(localStoreProvider)
+        .catalogue
+        .setMeta(MetaKeys.autoPrint, value ? '1' : '0');
+    state = state.copyWith(autoPrint: value);
+  }
+
+  Future<void> setOpenDrawer(bool value) async {
+    await _ref
+        .read(localStoreProvider)
+        .catalogue
+        .setMeta(MetaKeys.openDrawer, value ? '1' : '0');
+    state = state.copyWith(openDrawer: value);
+  }
+}
+
+final printerSettingsProvider =
+    StateNotifierProvider<PrinterSettingsController, PrinterSettings>(
+  (ref) => PrinterSettingsController(ref),
+);
+
+/// Printers the OS can currently see. Re-read whenever Settings is opened.
+final availablePrintersProvider = FutureProvider<List<Printer>>(
+  (ref) => ref.watch(receiptServiceProvider).availablePrinters(),
+);

lib/presentation/modules/screens/settings_view.dart

@@ -8,6 +8,7 @@ import '../../../core/theme/app_dimens.dart';
 import '../../../core/utils/formatters.dart';
 import '../../../domain/entities/store_account.dart';
 import '../../auth/providers/auth_controller.dart';
+import '../providers/printer_settings.dart';
 import '../../sync/providers/sync_controller.dart';
 import '../widgets/module_widgets.dart';
 
@@ -21,11 +22,8 @@ class SettingsView extends ConsumerStatefulWidget {
 
 class _SettingsViewState extends ConsumerState<SettingsView> {
   bool _scannerSound = true;
-  bool _autoPrint = true;
-  bool _openDrawer = true;
   bool _roundOff = true;
   bool _autoLoyalty = true;
-  bool _offline = false;
 
   @override
   Widget build(BuildContext context) {
@@ -138,36 +136,160 @@ class _SettingsViewState extends ConsumerState<SettingsView> {
         ),
       );
 
-  Widget _hardwareCard() => PanelCard(
+  Widget _hardwareCard() {
-        title: 'Hardware & peripherals',
+    final settings = ref.watch(printerSettingsProvider);
-        child: Column(
+    final controller = ref.read(printerSettingsProvider.notifier);
-          mainAxisSize: MainAxisSize.min,
+    final printers = ref.watch(availablePrintersProvider);
-          children: [
+
-            _toggle(
+    return PanelCard(
-              'Scanner beep',
+      title: 'Printer & peripherals',
-              'Audible confirmation on every scan',
+      subtitle: 'Install the printer in the operating system first — it then '
-              _scannerSound,
+          'appears in this list.',
-              (v) => setState(() => _scannerSound = v),
+      action: TextButton.icon(
+        onPressed: () => ref.invalidate(availablePrintersProvider),
+        icon: const Icon(Icons.refresh_rounded, size: 16),
+        label: const Text('Rescan'),
+      ),
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        crossAxisAlignment: CrossAxisAlignment.stretch,
+        children: [
+          printers.when(
+            loading: () => const Padding(
+              padding: EdgeInsets.symmetric(vertical: AppSpacing.lg),
+              child: Center(child: CircularProgressIndicator()),
             ),
-            _toggle(
+            error: (e, _) => Text(
-              'Print receipt automatically',
+              'Could not list printers: $e',
-              'Sends to the default roll printer with no dialog',
+              style: const TextStyle(color: AppColors.danger, fontSize: 12.5),
-              _autoPrint,
-              (v) => setState(() => _autoPrint = v),
             ),
-            _toggle(
+            data: (list) {
-              'Open cash drawer on cash sales',
+              if (list.isEmpty) {
-              'Sends the ESC/POS kick pulse',
+                return Container(
-              _openDrawer,
+                  padding: const EdgeInsets.all(AppSpacing.md),
-              (v) => setState(() => _openDrawer = v),
+                  decoration: BoxDecoration(
-            ),
+                    color: AppColors.warningSurface,
-            const Divider(height: AppSpacing.xxl),
+                    borderRadius: AppRadius.brSm,
-            _row('Receipt printer', 'EPSON TM-T82 (default)'),
+                  ),
-            _row('Barcode scanner', 'Keyboard wedge · detected'),
+                  child: const Row(
-            _row('Cash drawer', 'Connected via printer'),
+                    crossAxisAlignment: CrossAxisAlignment.start,
-          ],
+                    children: [
-        ),
+                      Icon(Icons.print_disabled_rounded,
-      );
+                          size: 18, color: AppColors.warning),
+                      SizedBox(width: AppSpacing.sm),
+                      Expanded(
+                        child: Text(
+                          'No printers found. Add the thermal printer in your '
+                          'operating system settings, then tap Rescan. Bills '
+                          'still print to screen in the meantime.',
+                          style: TextStyle(
+                            fontSize: 12.5,
+                            color: AppColors.warning,
+                            height: 1.45,
+                          ),
+                        ),
+                      ),
+                    ],
+                  ),
+                );
+              }
+
+              return Column(
+                mainAxisSize: MainAxisSize.min,
+                crossAxisAlignment: CrossAxisAlignment.stretch,
+                children: [
+                  DropdownButtonFormField<String>(
+                    initialValue: list.any((p) => p.url == settings.printerUrl)
+                        ? settings.printerUrl
+                        : null,
+                    isExpanded: true,
+                    decoration: const InputDecoration(
+                      labelText: 'Receipt printer',
+                      prefixIcon: Icon(Icons.print_outlined),
+                      isDense: true,
+                    ),
+                    hint: const Text('Print to screen only'),
+                    items: [
+                      for (final p in list)
+                        DropdownMenuItem(
+                          value: p.url,
+                          child: Text(
+                            p.isDefault ? '${p.name}  (system default)' : p.name,
+                            overflow: TextOverflow.ellipsis,
+                          ),
+                        ),
+                    ],
+                    onChanged: (url) => controller.selectPrinter(
+                      url == null
+                          ? null
+                          : list.firstWhere((p) => p.url == url),
+                    ),
+                  ),
+                  const SizedBox(height: AppSpacing.md),
+                  Wrap(
+                    spacing: AppSpacing.sm,
+                    runSpacing: AppSpacing.sm,
+                    children: [
+                      OutlinedButton.icon(
+                        onPressed: () async {
+                          final ok = await ref
+                              .read(receiptServiceProvider)
+                              .printTestPage(
+                                  printerUrl: settings.printerUrl);
+                          if (!context.mounted) return;
+                          ScaffoldMessenger.of(context)
+                            ..hideCurrentSnackBar()
+                            ..showSnackBar(SnackBar(
+                              backgroundColor: ok
+                                  ? AppColors.success
+                                  : AppColors.danger,
+                              content: Text(ok
+                                  ? 'Test slip sent to the printer.'
+                                  : 'Could not reach the printer.'),
+                            ));
+                        },
+                        icon: const Icon(Icons.receipt_long_rounded, size: 17),
+                        label: const Text('Print test slip'),
+                      ),
+                      if (settings.hasPrinter)
+                        TextButton(
+                          onPressed: () => controller.selectPrinter(null),
+                          style: TextButton.styleFrom(
+                            foregroundColor: AppColors.textSecondary,
+                          ),
+                          child: const Text('Use screen only'),
+                        ),
+                    ],
+                  ),
+                ],
+              );
+            },
+          ),
+          const Divider(height: AppSpacing.xxl),
+          _toggle(
+            'Scanner beep',
+            'Audible confirmation on every scan',
+            _scannerSound,
+            (v) => setState(() => _scannerSound = v),
+          ),
+          _toggle(
+            'Print receipt automatically',
+            settings.hasPrinter
+                ? 'Sends to the selected printer the moment a sale completes'
+                : 'Select a printer above to enable this',
+            settings.autoPrint,
+            settings.hasPrinter ? controller.setAutoPrint : null,
+          ),
+          _toggle(
+            'Open cash drawer on cash sales',
+            'Needs a raw ESC/POS link — see the notes in ReceiptService',
+            settings.openDrawer,
+            controller.setOpenDrawer,
+          ),
+        ],
+      ),
+    );
+  }
 
   Widget _staffCard(StoreAccount? store, StaffUser? current) => PanelCard(
         title: 'Users & roles',
@@ -212,13 +334,15 @@ class _SettingsViewState extends ConsumerState<SettingsView> {
           _row('Unsynced bills', '$outstanding'),
           _toggle(
             'Simulate offline',
-            'Forces import and push to fail, so you can confirm nothing is '
+            'Forces import and sync to fail, so you can confirm nothing is '
                 'lost when the network drops',
-            _offline,
+            // Read straight from the provider — no local copy to drift.
+            ref.watch(simulateOfflineProvider),
             (v) {
-              setState(() => _offline = v);
+              ref.read(simulateOfflineProvider.notifier).state = v;
-              ref.read(remoteCatalogueProvider).simulateOffline = v;
+              // Clear any stale failure banner left by the previous setting.
-              ref.read(remoteOrderSinkProvider).simulateOffline = v;
+              ref.read(catalogueImportProvider.notifier).reset();
+              ref.read(orderSyncProvider.notifier).reset();
             },
           ),
         ],
@@ -286,7 +410,7 @@ class _SettingsViewState extends ConsumerState<SettingsView> {
     String title,
     String subtitle,
     bool value,
-    ValueChanged<bool> onChanged,
+    ValueChanged<bool>? onChanged,
   ) =>
       Padding(
         padding: const EdgeInsets.symmetric(vertical: AppSpacing.xs),

lib/presentation/payment/providers/payment_controller.dart

@@ -74,11 +74,31 @@ class PaymentController extends StateNotifier<PaymentState> {
     return diff > 0 ? diff.asMoney : 0;
   }
 
+  /// Whether Complete Sale should be enabled.
+  ///
+  /// Cash is the strict case: the drawer cannot be reconciled and no change can
+  /// be calculated unless the cashier states what was handed over. Card, UPI
+  /// and wallet settle on the external terminal, so they need no amount here.
   bool get canConfirm {
+    if (_billTotal <= 0) return false;
+
+    // Staged splits already cover the bill.
+    if (balanceDue <= 0.01) return true;
+
     if (state.activeMethod.needsChange) {
-      return state.cashTendered >= balanceDue && balanceDue > 0;
+      return state.cashTendered >= balanceDue;
     }
-    return balanceDue > 0;
+    return true;
+  }
+
+  /// Why the button is disabled, for display next to it.
+  String? get blockedReason {
+    if (_billTotal <= 0) return 'Add at least one item before charging.';
+    if (canConfirm) return null;
+    if (state.activeMethod.needsChange) {
+      return 'Enter the cash received, or tap Exact.';
+    }
+    return null;
   }
 
   void selectMethod(PaymentMethod method) {
@@ -156,10 +176,10 @@ class PaymentController extends StateNotifier<PaymentState> {
 
       state = state.copyWith(isProcessing: false, result: result);
 
-      // Fire and forget — printing must never block the next sale.
+      // No auto-print: with no roll printer attached this silently failed and
-      final receipts = _ref.read(receiptServiceProvider);
+      // looked like a bug. The receipt screen shows the bill on the terminal
-      unawaited(receipts.printDirect(result.transaction));
+      // and offers Print, WhatsApp and Share explicitly.
-      unawaited(receipts.openCashDrawer());
+      unawaited(_ref.read(receiptServiceProvider).openCashDrawer());
       unawaited(_ref.read(soundServiceProvider).saleComplete());
 
       // Stock changed, so the grid must refresh; the new order changes the

lib/presentation/payment/screens/payment_screen.dart

@@ -125,7 +125,7 @@ class _PaymentScreenState extends ConsumerState<PaymentScreen> {
           );
         },
       ),
-      bottomNavigationBar: _bottomBar(cart.grandTotal, state, cart.isEmpty),
+      bottomNavigationBar: _bottomBar(controller, state, cart.grandTotal),
     );
   }
 
@@ -557,7 +557,15 @@ class _PaymentScreenState extends ConsumerState<PaymentScreen> {
   }
 
   // ------------------------------------------------------------ Bottom bar
-  Widget _bottomBar(double total, PaymentState state, bool cartEmpty) {
+  Widget _bottomBar(
+    PaymentController controller,
+    PaymentState state,
+    double total,
+  ) {
+    // A cash sale cannot complete until the cashier says what was handed over.
+    final canComplete = controller.canConfirm;
+    final reason = controller.blockedReason;
+
     return SafeArea(
       child: Container(
         padding: const EdgeInsets.fromLTRB(
@@ -599,13 +607,45 @@ class _PaymentScreenState extends ConsumerState<PaymentScreen> {
                   ],
                 ),
               ).animate().shake(duration: 300.ms, hz: 3),
+            if (reason != null && state.error == null)
+              Padding(
+                padding: const EdgeInsets.only(bottom: AppSpacing.sm),
+                child: Row(
+                  children: [
+                    const Icon(Icons.info_outline_rounded,
+                        size: 15, color: AppColors.textTertiary),
+                    const SizedBox(width: AppSpacing.sm),
+                    Expanded(
+                      child: Text(
+                        reason,
+                        style: const TextStyle(
+                          fontSize: 12.5,
+                          color: AppColors.textTertiary,
+                        ),
+                      ),
+                    ),
+                    if (state.activeMethod.needsChange)
+                      TextButton(
+                        onPressed: () => _setCash(controller.balanceDue),
+                        style: TextButton.styleFrom(
+                          minimumSize: const Size(0, 30),
+                          padding: const EdgeInsets.symmetric(
+                            horizontal: AppSpacing.md,
+                          ),
+                        ),
+                        child: const Text('Exact',
+                            style: TextStyle(fontSize: 12.5)),
+                      ),
+                  ],
+                ),
+              ),
             PrimaryButton(
               label: 'Complete Sale',
               icon: Icons.check_circle_outline_rounded,
               large: true,
               tone: ButtonTone.success,
               busy: state.isProcessing,
-              onPressed: cartEmpty ? null : _confirm,
+              onPressed: canComplete ? _confirm : null,
               trailing: Text(
                 Formatters.money(total),
                 style: AppTypography.money(19, color: Colors.white),

lib/presentation/pos/widgets/billing_panel.dart

@@ -12,6 +12,7 @@ import '../../../core/utils/formatters.dart';
 import '../../../core/widgets/empty_state.dart';
 import '../../../core/widgets/primary_button.dart';
 import '../../../domain/entities/cart.dart';
+import '../../customer/widgets/customer_capture_sheet.dart';
 import '../providers/cart_controller.dart';
 import 'cart_line_tile.dart';
 import 'discount_sheet.dart';
@@ -404,7 +405,16 @@ class _Actions extends ConsumerWidget {
       child: PrimaryButton(
         label: 'CHARGE',
         large: true,
-        onPressed: enabled ? () => context.push(AppRoutes.payment) : null,
+        onPressed: enabled
+            ? () async {
+                // Ask once per bill, before payment. Skipping is one tap and
+                // leaves the sale as walk-in.
+                if (ref.read(cartControllerProvider).customer == null) {
+                  await showCustomerCaptureSheet(context);
+                }
+                if (context.mounted) context.push(AppRoutes.payment);
+              }
+            : null,
         trailing: enabled
             ? Text(
                 Formatters.money(cart.grandTotal),

lib/presentation/pos/widgets/customer_bar.dart

@@ -19,9 +19,16 @@ class CustomerBar extends ConsumerWidget {
     );
 
     return Container(
-      height: AppSizes.customerBarHeight,
+      // A hard height clipped the subtitle once it wrapped. Minimum height
+      // keeps the strip its usual size but lets it grow if it must.
+      constraints: const BoxConstraints(
+        minHeight: AppSizes.customerBarHeight,
+      ),
       color: AppColors.surface,
-      padding: const EdgeInsets.symmetric(horizontal: AppSpacing.xxl),
+      padding: const EdgeInsets.symmetric(
+        horizontal: AppSpacing.xl,
+        vertical: AppSpacing.sm,
+      ),
       child: Row(children: [
         CircleAvatar(
           radius: 20,
@@ -63,11 +70,17 @@ class CustomerBar extends ConsumerWidget {
                 Text(
                   '${Formatters.mobile(customer.mobile)}  ·  '
                   '${customer.loyaltyPoints} pts',
+                  maxLines: 1,
+                  overflow: TextOverflow.ellipsis,
                   style: context.text.bodySmall,
                 )
               else
-                Text('No loyalty tracking for this sale',
+                Text(
-                    style: context.text.bodySmall),
+                  'No loyalty tracking for this sale',
+                  maxLines: 1,
+                  overflow: TextOverflow.ellipsis,
+                  style: context.text.bodySmall,
+                ),
             ],
           ),
         ),

lib/presentation/pos/widgets/page_header.dart

@@ -24,11 +24,27 @@ class PageHeader extends ConsumerWidget {
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
+    final compact = layout.sidebarIsDrawer;
+
+    // Measured from the header's own box, not the window. The window can be
+    // wide while this column is narrow — the sidebar and the docked bill both
+    // take from it — which is how the status chrome ended up overflowing.
+    return LayoutBuilder(
+      builder: (context, box) {
+        final showStatus = box.maxWidth >= 720;
+        return _bar(context, ref, compact, showStatus);
+      },
+    );
+  }
+
+  Widget _bar(
+    BuildContext context,
+    WidgetRef ref,
+    bool compact,
+    bool showStatus,
+  ) {
     final module = ref.watch(activeModuleProvider);
     final now = ref.watch(clockProvider).value ?? DateTime.now();
-    final compact = layout.sidebarIsDrawer;
-    // Status chrome is the first thing dropped when width gets tight.
-    final showStatus = MediaQuery.sizeOf(context).width >= 1180;
 
     return Container(
       constraints: const BoxConstraints(minHeight: AppSizes.headerHeight),
@@ -76,7 +92,7 @@ class PageHeader extends ConsumerWidget {
           const Spacer(),
 
           if (showStatus) ...[
-            const _LivePill(),
+            _LivePill(offline: ref.watch(simulateOfflineProvider)),
             const SizedBox(width: AppSpacing.lg),
             Text(
               Formatters.time(now),
@@ -139,7 +155,9 @@ class _Breadcrumb extends StatelessWidget {
 }
 
 class _LivePill extends StatefulWidget {
-  const _LivePill();
+  const _LivePill({required this.offline});
+
+  final bool offline;
 
   @override
   State<_LivePill> createState() => _LivePillState();
@@ -160,40 +178,48 @@ class _LivePillState extends State<_LivePill>
 
   @override
   Widget build(BuildContext context) {
-    return Container(
+    final offline = widget.offline;
-      padding: const EdgeInsets.symmetric(
+    final tone = offline ? AppColors.warning : AppColors.success;
-        horizontal: AppSpacing.md,
+    final surface =
-        vertical: AppSpacing.xs + 2,
+        offline ? AppColors.warningSurface : AppColors.successSurface;
-      ),
+
-      decoration: BoxDecoration(
+    return Tooltip(
-        color: AppColors.successSurface,
+      message: offline
-        borderRadius: AppRadius.brPill,
+          ? 'Simulate offline is ON in Settings — imports and syncs are being '
-      ),
+              'failed deliberately.'
-      child: Row(
+          : 'Terminal is operating normally.',
-        mainAxisSize: MainAxisSize.min,
+      child: Container(
-        children: [
+        padding: const EdgeInsets.symmetric(
-          FadeTransition(
+          horizontal: AppSpacing.md,
-            opacity: _c,
+          vertical: AppSpacing.xs + 2,
-            child: Container(
+        ),
-              width: 7,
+        decoration: BoxDecoration(
-              height: 7,
+          color: surface,
-              decoration: const BoxDecoration(
+          borderRadius: AppRadius.brPill,
-                color: AppColors.success,
+        ),
-                shape: BoxShape.circle,
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            FadeTransition(
+              opacity: _c,
+              child: Container(
+                width: 7,
+                height: 7,
+                decoration: BoxDecoration(color: tone, shape: BoxShape.circle),
               ),
             ),
-          ),
+            const SizedBox(width: AppSpacing.xs + 2),
-          const SizedBox(width: AppSpacing.xs + 2),
+            Text(
-          const Text(
+              offline ? 'OFFLINE (SIM)' : 'LIVE',
-            'LIVE',
+              style: TextStyle(
-            style: TextStyle(
+                color: tone,
-              color: AppColors.success,
+                fontSize: 10.5,
-              fontSize: 10.5,
+                fontWeight: FontWeight.w700,
-              fontWeight: FontWeight.w700,
+                letterSpacing: 0.8,
-              letterSpacing: 0.8,
+              ),
             ),
-          ),
+          ],
-        ],
+        ),
       ),
     );
   }

lib/presentation/pos/widgets/product_card.dart

@@ -62,80 +62,114 @@ class _ProductCardState extends State<ProductCard> {
                   : AppColors.shadowSm,
             ),
             child: Stack(children: [
-              Padding(
+              // The grid gives tiles a width derived from the viewport, so
-                padding: const EdgeInsets.all(AppSpacing.md),
+              // on narrow screens they can be far shorter than the content's
-                child: Column(
+              // natural height. Everything is sized from the box we actually
-                  mainAxisAlignment: MainAxisAlignment.center,
+              // get rather than from fixed constants.
-                  children: [
+              LayoutBuilder(
-                    Opacity(
+                builder: (context, box) {
-                      opacity: disabled ? 0.4 : 1,
+                  final h = box.maxHeight;
-                      child: Text(p.emoji,
+                  final tight = h < 170;
-                          style: const TextStyle(fontSize: 40)),
+
+                  final emoji = (h * 0.22).clamp(20.0, 38.0);
+                  final nameSize = tight ? 12.0 : 13.5;
+                  final priceSize = tight ? 14.0 : 16.0;
+
+                  return Padding(
+                    padding: EdgeInsets.all(
+                      tight ? AppSpacing.sm : AppSpacing.md,
                     ),
-                    const SizedBox(height: AppSpacing.sm),
+                    child: Column(
-                    Text(
+                      mainAxisAlignment: MainAxisAlignment.center,
-                      p.name,
+                      mainAxisSize: MainAxisSize.min,
-                      maxLines: 2,
+                      children: [
-                      textAlign: TextAlign.center,
+                        Opacity(
-                      overflow: TextOverflow.ellipsis,
+                          opacity: disabled ? 0.4 : 1,
-                      style: TextStyle(
+                          child: Text(
-                        fontSize: 14,
+                            p.emoji,
-                        fontWeight: FontWeight.w600,
+                            style: TextStyle(fontSize: emoji),
-                        height: 1.25,
+                          ),
-                        color: disabled
+                        ),
-                            ? AppColors.textTertiary
+                        SizedBox(height: tight ? 2 : AppSpacing.sm),
-                            : AppColors.textPrimary,
+
-                      ),
+                        // Flexible so a long name gives way instead of
-                    ),
+                        // pushing the price and stock line out of the tile.
-                    const SizedBox(height: AppSpacing.xs + 2),
+                        Flexible(
-                    // Scales down rather than overflowing on small tiles.
+                          child: Text(
-                    FittedBox(
+                            p.name,
-                      fit: BoxFit.scaleDown,
+                            maxLines: tight ? 1 : 2,
-                      child: Row(
+                            textAlign: TextAlign.center,
-                        mainAxisSize: MainAxisSize.min,
+                            overflow: TextOverflow.ellipsis,
-                        crossAxisAlignment: CrossAxisAlignment.end,
+                            style: TextStyle(
-                        children: [
+                              fontSize: nameSize,
-                        Text(
+                              fontWeight: FontWeight.w600,
-                          Formatters.money(p.price),
+                              height: 1.2,
-                          style: AppTypography.money(17,
                               color: disabled
                                   ? AppColors.textTertiary
-                                  : AppColors.primary),
+                                  : AppColors.textPrimary,
-                        ),
+                            ),
-                        if (p.hasDiscount) ...[
+                          ),
-                          const SizedBox(width: AppSpacing.xs + 2),
+                        ),
-                          Padding(
+                        SizedBox(height: tight ? 2 : AppSpacing.xs),
-                            padding: const EdgeInsets.only(bottom: 1.5),
+
-                            child: Text(
+                        FittedBox(
-                              Formatters.money(p.mrp!),
+                          fit: BoxFit.scaleDown,
-                              style: const TextStyle(
+                          child: Row(
-                                fontSize: 11.5,
+                            mainAxisSize: MainAxisSize.min,
-                                color: AppColors.textTertiary,
+                            crossAxisAlignment: CrossAxisAlignment.end,
-                                decoration: TextDecoration.lineThrough,
+                            children: [
-                              ),
+                              Text(
+                                Formatters.money(p.price),
+                                style: AppTypography.money(
+                                  priceSize,
+                                  color: disabled
+                                      ? AppColors.textTertiary
+                                      : AppColors.primary,
+                                ),
+                              ),
+                              if (p.hasDiscount && !tight) ...[
+                                const SizedBox(width: AppSpacing.xs),
+                                Padding(
+                                  padding: const EdgeInsets.only(bottom: 1.5),
+                                  child: Text(
+                                    Formatters.money(p.mrp!),
+                                    style: const TextStyle(
+                                      fontSize: 11,
+                                      color: AppColors.textTertiary,
+                                      decoration:
+                                          TextDecoration.lineThrough,
+                                    ),
+                                  ),
+                                ),
+                              ],
+                            ],
+                          ),
+                        ),
+
+                        // Dropped first when the tile is too short for it.
+                        if (h >= 140) ...[
+                          const SizedBox(height: 2),
+                          Text(
+                            disabled
+                                ? 'Out of stock'
+                                : '${p.stock.toStringAsFixed(0)} in stock',
+                            maxLines: 1,
+                            overflow: TextOverflow.ellipsis,
+                            style: TextStyle(
+                              fontSize: 11,
+                              fontWeight: FontWeight.w500,
+                              color: disabled
+                                  ? AppColors.danger
+                                  : (p.isLowStock
+                                      ? AppColors.warning
+                                      : AppColors.textTertiary),
                             ),
                           ),
-                          ],
                         ],
-                      ),
+                      ],
                     ),
-                    const SizedBox(height: AppSpacing.xs),
+                  );
-                    Text(
+                },
-                      disabled
-                          ? 'Out of stock'
-                          : '${p.stock.toStringAsFixed(0)} in stock',
-                      style: TextStyle(
-                        fontSize: 11.5,
-                        fontWeight: FontWeight.w500,
-                        color: disabled
-                            ? AppColors.danger
-                            : (p.isLowStock
-                                ? AppColors.warning
-                                : AppColors.textTertiary),
-                      ),
-                    ),
-                  ],
-                ),
               ),
 
               if (p.hasDiscount && !disabled)

lib/presentation/pos/widgets/product_grid.dart

@@ -61,7 +61,10 @@ class ProductGrid extends ConsumerWidget {
             maxCrossAxisExtent: tileExtent,
             mainAxisSpacing: AppSpacing.md,
             crossAxisSpacing: AppSpacing.md,
-            childAspectRatio: AppSizes.productCardAspect,
+            // A fixed height, not a ratio. With childAspectRatio the tile grew
+            // taller as the column got wider, leaving a large empty band under
+            // every card on a full-screen window.
+            mainAxisExtent: 186,
           ),
           itemCount: items.length,
           itemBuilder: (context, i) {

lib/presentation/receipt/screens/receipt_screen.dart

@@ -16,6 +16,7 @@ import '../../../core/utils/formatters.dart';
 import '../../../core/widgets/glass_card.dart';
 import '../../../core/widgets/primary_button.dart';
 import '../../../domain/entities/transaction.dart';
+import '../../modules/providers/printer_settings.dart';
 import '../../pos/providers/cart_controller.dart';
 import '../widgets/receipt_preview.dart';
 
@@ -37,6 +38,30 @@ class _ReceiptScreenState extends ConsumerState<ReceiptScreen> {
   @override
   void initState() {
     super.initState();
+
+    // Auto-print is opt-in and only fires when a printer was actually
+    // selected, so it can never fail invisibly on a terminal with none.
+    WidgetsBinding.instance.addPostFrameCallback((_) async {
+      final settings = ref.read(printerSettingsProvider);
+      if (!settings.autoPrint || !settings.hasPrinter) return;
+
+      final ok = await ref.read(receiptServiceProvider).printDirect(
+            widget.transaction,
+            printerUrl: settings.printerUrl,
+          );
+      if (!ok && mounted) {
+        _cancelAutoReturn();
+        ScaffoldMessenger.of(context)
+          ..hideCurrentSnackBar()
+          ..showSnackBar(const SnackBar(
+            backgroundColor: AppColors.danger,
+            content: Text(
+              'Printer did not respond — use Print to send it again.',
+            ),
+          ));
+      }
+    });
+
     _timer = Timer.periodic(const Duration(seconds: 1), (t) {
       if (!mounted) return;
       setState(() => _seconds--);
@@ -182,31 +207,85 @@ class _ReceiptScreenState extends ConsumerState<ReceiptScreen> {
           ),
 
           const SizedBox(height: AppSpacing.xxl),
-          Row(children: [
+          // Wrap, so three actions never overflow a narrow terminal.
-            Expanded(
+          Wrap(
-              child: PrimaryButton(
+            spacing: AppSpacing.md,
-                label: 'Reprint',
+            runSpacing: AppSpacing.md,
-                icon: Icons.print_outlined,
+            children: [
-                tone: ButtonTone.neutral,
+              SizedBox(
-                onPressed: () {
+                width: 150,
-                  _cancelAutoReturn();
+                child: PrimaryButton(
-                  ref.read(receiptServiceProvider).printWithDialog(txn);
+                  label: 'Print',
-                },
+                  icon: Icons.print_outlined,
+                  tone: ButtonTone.neutral,
+                  onPressed: () async {
+                    _cancelAutoReturn();
+                    final settings = ref.read(printerSettingsProvider);
+                    final service = ref.read(receiptServiceProvider);
+
+                    // Straight to the roll when one is configured; otherwise
+                    // the system preview, which works with no hardware.
+                    final printed = settings.hasPrinter &&
+                        await service.printDirect(
+                          txn,
+                          printerUrl: settings.printerUrl,
+                        );
+                    if (!printed) await service.printPreview(txn);
+                  },
+                ),
+              ),
+              SizedBox(
+                width: 170,
+                child: PrimaryButton(
+                  label: 'WhatsApp',
+                  icon: Icons.chat_rounded,
+                  tone: txn.customer == null
+                      ? ButtonTone.neutral
+                      : ButtonTone.ghost,
+                  onPressed: txn.customer == null
+                      ? null
+                      : () async {
+                          _cancelAutoReturn();
+                          final sent = await ref
+                              .read(receiptServiceProvider)
+                              .sendToWhatsApp(txn);
+                          if (!context.mounted || sent) return;
+                          ScaffoldMessenger.of(context)
+                            ..hideCurrentSnackBar()
+                            ..showSnackBar(const SnackBar(
+                              content: Text(
+                                'Could not open WhatsApp on this device.',
+                              ),
+                            ));
+                        },
+                ),
+              ),
+              SizedBox(
+                width: 170,
+                child: PrimaryButton(
+                  label: 'Share PDF',
+                  icon: Icons.ios_share_rounded,
+                  tone: ButtonTone.neutral,
+                  onPressed: () {
+                    _cancelAutoReturn();
+                    ref.read(receiptServiceProvider).sharePdf(txn);
+                  },
+                ),
+              ),
+            ],
+          ),
+          if (txn.customer == null)
+            const Padding(
+              padding: EdgeInsets.only(top: AppSpacing.sm),
+              child: Text(
+                'No mobile number captured, so WhatsApp is unavailable for '
+                'this bill.',
+                style: TextStyle(
+                  fontSize: 12,
+                  color: AppColors.textTertiary,
+                ),
               ),
             ),
-            const SizedBox(width: AppSpacing.md),
-            Expanded(
-              child: PrimaryButton(
-                label: 'Share',
-                icon: Icons.ios_share_rounded,
-                tone: ButtonTone.neutral,
-                onPressed: () {
-                  _cancelAutoReturn();
-                  ref.read(receiptServiceProvider).share(txn);
-                },
-              ),
-            ),
-          ]),
           const SizedBox(height: AppSpacing.md),
           PrimaryButton(
             label: _seconds > 0

lib/presentation/receipt/widgets/receipt_preview.dart

@@ -5,6 +5,7 @@ import '../../../core/theme/app_colors.dart';
 import '../../../core/theme/app_dimens.dart';
 import '../../../core/theme/app_typography.dart';
 import '../../../core/utils/formatters.dart';
+import '../../../domain/entities/cart.dart';
 import '../../../domain/entities/transaction.dart';
 
 /// Paper-like preview of what the thermal printer produced.
@@ -13,10 +14,33 @@ class ReceiptPreview extends StatelessWidget {
 
   final SaleTransaction transaction;
 
+  /// Groups the bill by GST rate, mirroring how the printed invoice lists it.
+  List<_PreviewSlab> _slabs(SaleTransaction txn) {
+    final cart = txn.cart;
+    final factor = cart.subtotal <= 0 ? 1.0 : cart.netAmount / cart.subtotal;
+
+    final grouped = <double, List<CartLine>>{};
+    for (final line in cart.lines) {
+      grouped.putIfAbsent(line.product.gstRate, () => []).add(line);
+    }
+
+    final rates = grouped.keys.toList()..sort();
+    return [
+      for (var i = 0; i < rates.length; i++)
+        _PreviewSlab(i + 1, rates[i], grouped[rates[i]]!, factor),
+    ];
+  }
+
+  double _gross(SaleTransaction txn) => txn.cart.lines
+      .fold(0.0, (s, l) => s + (l.product.mrp ?? l.product.price) * l.quantity);
+
   @override
   Widget build(BuildContext context) {
     final txn = transaction;
     final cart = txn.cart;
+    final slabs = _slabs(txn);
+    final gross = _gross(txn);
+    final discount = gross - cart.netAmount;
 
     return Container(
       decoration: BoxDecoration(
@@ -29,14 +53,15 @@ class ReceiptPreview extends StatelessWidget {
         Expanded(
           child: SingleChildScrollView(
             padding: const EdgeInsets.symmetric(
-              horizontal: AppSpacing.xxl,
+              horizontal: AppSpacing.xl,
-              vertical: AppSpacing.xl,
+              vertical: AppSpacing.lg,
             ),
             child: DefaultTextStyle(
-              style: AppTypography.mono(11.5, color: AppColors.textPrimary),
+              style: AppTypography.mono(10, color: AppColors.textPrimary),
               child: Column(
                 crossAxisAlignment: CrossAxisAlignment.stretch,
                 children: [
+                  // ------------------------------------------------ header
                   Center(
                     child: Column(children: [
                       Text(
@@ -44,117 +69,251 @@ class ReceiptPreview extends StatelessWidget {
                         style: AppTypography.mono(15)
                             .copyWith(fontWeight: FontWeight.w700),
                       ),
-                      const SizedBox(height: 3),
+                      Text(AppConstants.storeLegalName,
+                          style: AppTypography.mono(8.5)),
+                      const SizedBox(height: 2),
                       Text(AppConstants.storeAddress,
                           textAlign: TextAlign.center,
-                          style: AppTypography.mono(9.5)),
+                          style: AppTypography.mono(8.5)),
-                      Text('GSTIN: ${AppConstants.storeGstin}',
+                      Text('Customer care : ${AppConstants.storePhone}',
-                          style: AppTypography.mono(9.5)),
+                          style: AppTypography.mono(8.5)),
-                      const SizedBox(height: AppSpacing.sm),
+                      Text('CIN No : ${AppConstants.storeCin}',
-                      Text('TAX INVOICE',
+                          style: AppTypography.mono(8.5)),
-                          style: AppTypography.mono(11.5)
+                      Text('GSTIN : ${AppConstants.storeGstin}',
-                              .copyWith(fontWeight: FontWeight.w700)),
+                          style: AppTypography.mono(8.5)),
+                      Text('FSSAI Lic No : ${AppConstants.storeFssai}',
+                          style: AppTypography.mono(8.5)),
                     ]),
                   ),
 
-                  const _Dashes(),
+                  if (discount > 0) ...[
-                  _row('Invoice', txn.invoiceNumber),
+                    const SizedBox(height: AppSpacing.sm),
-                  _row('Date', Formatters.receiptStamp(txn.createdAt)),
+                    Center(
-                  _row('Cashier', txn.cashierName),
+                      child: Text(
-                  _row('Customer', txn.customer?.name ?? 'Walk-in'),
+                        'You have saved Rs.${discount.toStringAsFixed(2)}',
-
+                        style: AppTypography.mono(11).copyWith(
-                  const _Dashes(),
+                          fontWeight: FontWeight.w700,
-                  Row(children: [
-                    Expanded(flex: 5, child: _bold('Item')),
-                    Expanded(
-                      flex: 2,
-                      child: _bold('Qty', align: TextAlign.center),
-                    ),
-                    Expanded(
-                      flex: 3,
-                      child: _bold('Amount', align: TextAlign.right),
-                    ),
-                  ]),
-                  const SizedBox(height: AppSpacing.xs),
-
-                  ...cart.lines.map((line) => Padding(
-                        padding: const EdgeInsets.symmetric(vertical: 2.5),
-                        child: Row(children: [
-                          Expanded(flex: 5, child: Text(line.product.name)),
-                          Expanded(
-                            flex: 2,
-                            child: Text(
-                              line.quantity % 1 == 0
-                                  ? line.quantity.toStringAsFixed(0)
-                                  : line.quantity.toStringAsFixed(2),
-                              textAlign: TextAlign.center,
-                            ),
-                          ),
-                          Expanded(
-                            flex: 3,
-                            child: Text(
-                              line.payable.toStringAsFixed(2),
-                              textAlign: TextAlign.right,
-                            ),
-                          ),
-                        ]),
-                      )),
-
-                  const _Dashes(),
-                  _row('Subtotal', cart.subtotal.toStringAsFixed(2)),
-                  if (cart.billDiscountTotal > 0)
-                    _row('Discount',
-                        '-${cart.billDiscountTotal.toStringAsFixed(2)}'),
-                  if (cart.loyaltyRedemptionValue > 0)
-                    _row('Points redeemed',
-                        '-${cart.loyaltyRedemptionValue.toStringAsFixed(2)}'),
-                  _row('CGST', cart.cgst.toStringAsFixed(2)),
-                  _row('SGST', cart.sgst.toStringAsFixed(2)),
-                  if (cart.roundOff != 0)
-                    _row('Round off', cart.roundOff.toStringAsFixed(2)),
-
-                  const _Dashes(),
-                  Row(
-                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
-                    children: [
-                      Text('TOTAL',
-                          style: AppTypography.mono(15).copyWith(
-                            fontWeight: FontWeight.w800,
-                            color: AppColors.textPrimary,
-                          )),
-                      Text(
-                        Formatters.money(txn.total),
-                        style: AppTypography.mono(15).copyWith(
-                          fontWeight: FontWeight.w800,
                           color: AppColors.textPrimary,
                         ),
                       ),
-                    ],
+                    ),
-                  ),
+                  ],
 
                   const _Dashes(),
-                  ...txn.payments.map((p) =>
+                  Center(
-                      _row(p.method.label, p.amount.toStringAsFixed(2))),
+                    child: Column(children: [
-                  if (txn.changeDue > 0)
+                      Text('TAX INVOICE',
-                    _row('Change', txn.changeDue.toStringAsFixed(2)),
+                          style: AppTypography.mono(11)
+                              .copyWith(fontWeight: FontWeight.w700)),
+                      Text('xxxxxx Original for Recipient xxxxxx',
+                          style: AppTypography.mono(8)),
+                    ]),
+                  ),
+                  const SizedBox(height: AppSpacing.sm),
 
-                  if (txn.customer != null) ...[
+                  // -------------------------------------------------- meta
-                    const _Dashes(),
+                  _plain('Place of Supply & State Code: '
-                    _row('Points earned', '+${txn.pointsEarned}'),
+                      '${AppConstants.stateCode} ${AppConstants.stateName}'),
-                    _row('Membership', txn.customer!.tier.label),
+                  _plain('Customer Type: '
+                      '${txn.customer == null ? 'URD' : 'REG'}'),
+                  _row('Date:${Formatters.receiptStamp(txn.createdAt)}',
+                      'Bill No:${txn.invoiceNumber.split('-').last}'),
+                  _row(
+                    'Store:${AppConstants.storeCode} '
+                        'Cashier:${txn.cashierName}',
+                    'Pos:${AppConstants.posNumber}',
+                  ),
+                  if (txn.customer != null)
+                    _plain('Customer: ${txn.customer!.name}  '
+                        '${txn.customer!.mobile}'),
+
+                  const _Dashes(),
+
+                  // ------------------------------------------------- items
+                  Row(children: [
+                    Expanded(flex: 12, child: _bold('HSN')),
+                    Expanded(flex: 34, child: _bold('Item Description')),
+                    Expanded(
+                        flex: 16,
+                        child: _bold('Net Price', align: TextAlign.right)),
+                    Expanded(
+                        flex: 8, child: _bold('Qty', align: TextAlign.right)),
+                    Expanded(
+                        flex: 18,
+                        child: _bold('Value', align: TextAlign.right)),
+                  ]),
+                  const SizedBox(height: 3),
+
+                  for (final slab in slabs) ...[
+                    Padding(
+                      padding: const EdgeInsets.only(top: 5, bottom: 2),
+                      child: Text(
+                        '${slab.index}) CGST @ ${slab.halfPercent}  '
+                        'SGST @ ${slab.halfPercent}',
+                        style: AppTypography.mono(9).copyWith(
+                          fontWeight: FontWeight.w700,
+                          color: AppColors.textPrimary,
+                        ),
+                      ),
+                    ),
+                    for (final line in slab.lines)
+                      Padding(
+                        padding: const EdgeInsets.symmetric(vertical: 1.5),
+                        child: Row(children: [
+                          Expanded(
+                              flex: 12,
+                              child: _cell(line.product.hsnCode ?? '-')),
+                          Expanded(
+                              flex: 34,
+                              child:
+                                  _cell(line.product.name.toUpperCase())),
+                          Expanded(
+                            flex: 16,
+                            child: _cell(
+                                line.product.price.toStringAsFixed(2),
+                                align: TextAlign.right),
+                          ),
+                          Expanded(
+                            flex: 8,
+                            child: _cell(_qty(line.quantity),
+                                align: TextAlign.right),
+                          ),
+                          Expanded(
+                            flex: 18,
+                            child: _cell(line.payable.toStringAsFixed(2),
+                                align: TextAlign.right),
+                          ),
+                        ]),
+                      ),
                   ],
 
+                  const _Dashes(),
+
+                  // ------------------------------------------------ totals
+                  _row('Items:${cart.lineCount}',
+                      'Qty:${_qty(cart.totalQuantity)}   '
+                          '${cart.netAmount.toStringAsFixed(2)}'),
+                  const SizedBox(height: 3),
+                  _amount('Gross Sales Value', gross),
+                  if (discount > 0) _amount('Total Discount', discount),
+                  _amount(
+                      'Net Sales Value (Inclusive of GST)', cart.netAmount),
+                  if (cart.roundOff != 0)
+                    _amount('Round Off', cart.roundOff),
+                  _amount('Total Amount Paid', txn.total, bold: true),
+                  for (final p in txn.payments)
+                    _amount(p.method.label.toUpperCase(), p.amount),
+                  if (txn.changeDue > 0)
+                    _amount('Change Returned', txn.changeDue),
+                  Text('(AMOUNT INCLUSIVE OF APPLICABLE TAXES)',
+                      style: AppTypography.mono(8)),
+
+                  const SizedBox(height: AppSpacing.md),
+
+                  // ------------------------------------------- gst breakup
+                  Center(
+                    child: Text('------GST Breakup Details------ Amount (INR)',
+                        style: AppTypography.mono(8.5)),
+                  ),
+                  const SizedBox(height: 4),
+                  Row(children: [
+                    Expanded(flex: 10, child: _bold('GST')),
+                    Expanded(
+                        flex: 20,
+                        child: _bold('Taxable', align: TextAlign.right)),
+                    Expanded(
+                        flex: 16,
+                        child: _bold('CGST', align: TextAlign.right)),
+                    Expanded(
+                        flex: 16,
+                        child: _bold('SGST', align: TextAlign.right)),
+                    Expanded(
+                        flex: 14,
+                        child: _bold('CESS', align: TextAlign.right)),
+                    Expanded(
+                        flex: 20,
+                        child: _bold('Total', align: TextAlign.right)),
+                  ]),
+                  const SizedBox(height: 2),
+                  for (final s in slabs)
+                    Padding(
+                      padding: const EdgeInsets.symmetric(vertical: 1),
+                      child: Row(children: [
+                        Expanded(flex: 10, child: _cell('${s.index}')),
+                        Expanded(
+                            flex: 20,
+                            child: _cell(s.taxable.toStringAsFixed(2),
+                                align: TextAlign.right)),
+                        Expanded(
+                            flex: 16,
+                            child: _cell(s.cgst.toStringAsFixed(2),
+                                align: TextAlign.right)),
+                        Expanded(
+                            flex: 16,
+                            child: _cell(s.sgst.toStringAsFixed(2),
+                                align: TextAlign.right)),
+                        Expanded(
+                            flex: 14,
+                            child: _cell('0.00', align: TextAlign.right)),
+                        Expanded(
+                            flex: 20,
+                            child: _cell(s.total.toStringAsFixed(2),
+                                align: TextAlign.right)),
+                      ]),
+                    ),
+                  const _Dashes(),
+                  Row(children: [
+                    Expanded(flex: 10, child: _bold('Total')),
+                    Expanded(
+                        flex: 20,
+                        child: _bold(
+                            slabs
+                                .fold(0.0, (a, s) => a + s.taxable)
+                                .toStringAsFixed(2),
+                            align: TextAlign.right)),
+                    Expanded(
+                        flex: 16,
+                        child: _bold(
+                            slabs
+                                .fold(0.0, (a, s) => a + s.cgst)
+                                .toStringAsFixed(2),
+                            align: TextAlign.right)),
+                    Expanded(
+                        flex: 16,
+                        child: _bold(
+                            slabs
+                                .fold(0.0, (a, s) => a + s.sgst)
+                                .toStringAsFixed(2),
+                            align: TextAlign.right)),
+                    Expanded(
+                        flex: 14,
+                        child: _bold('0.00', align: TextAlign.right)),
+                    Expanded(
+                        flex: 20,
+                        child: _bold(
+                            slabs
+                                .fold(0.0, (a, s) => a + s.total)
+                                .toStringAsFixed(2),
+                            align: TextAlign.right)),
+                  ]),
+
+                  const _Dashes(),
+                  _plain('TaxInvoice# ${txn.invoiceNumber}'),
+                  if (txn.customer != null)
+                    _plain('Loyalty Pts: earned ${txn.pointsEarned}  '
+                        'Bal: ${txn.customer!.loyaltyPoints - txn.pointsRedeemed + txn.pointsEarned}'),
+                  _plain('Terms & Conditions Apply'),
+
                   const SizedBox(height: AppSpacing.lg),
                   Center(
                     child: Column(children: [
                       _FakeBarcode(value: txn.invoiceNumber),
                       const SizedBox(height: AppSpacing.sm),
-                      Text('Thank you for shopping with us!',
+                      Text('* Thank You for Shopping with us *',
-                          style: AppTypography.mono(11)
+                          style: AppTypography.mono(10)
                               .copyWith(fontWeight: FontWeight.w700)),
-                      const SizedBox(height: 2),
                       Text('Powered by Nearle POS',
-                          style: AppTypography.mono(9)),
+                          style: AppTypography.mono(8)),
                     ]),
                   ),
                 ],
@@ -167,22 +326,97 @@ class ReceiptPreview extends StatelessWidget {
     );
   }
 
-  Widget _row(String label, String value) => Padding(
+  String _qty(double q) =>
-        padding: const EdgeInsets.symmetric(vertical: 1.5),
+      q % 1 == 0 ? q.toStringAsFixed(0) : q.toStringAsFixed(3);
+
+  Widget _plain(String text) => Padding(
+        padding: const EdgeInsets.symmetric(vertical: 0.8),
+        child: Text(text, style: AppTypography.mono(9)),
+      );
+
+  Widget _row(String left, String right) => Padding(
+        padding: const EdgeInsets.symmetric(vertical: 0.8),
         child: Row(
           mainAxisAlignment: MainAxisAlignment.spaceBetween,
-          children: [Text(label), Text(value)],
+          children: [
+            Flexible(
+              child: Text(left,
+                  overflow: TextOverflow.ellipsis,
+                  style: AppTypography.mono(9)),
+            ),
+            const SizedBox(width: AppSpacing.sm),
+            Text(right, style: AppTypography.mono(9)),
+          ],
+        ),
+      );
+
+  Widget _amount(String label, double value, {bool bold = false}) => Padding(
+        padding: const EdgeInsets.symmetric(vertical: 1),
+        child: Row(
+          mainAxisAlignment: MainAxisAlignment.spaceBetween,
+          children: [
+            Flexible(
+              child: Text(
+                label,
+                overflow: TextOverflow.ellipsis,
+                style: AppTypography.mono(9.5).copyWith(
+                  fontWeight: bold ? FontWeight.w700 : FontWeight.w400,
+                  color: AppColors.textPrimary,
+                ),
+              ),
+            ),
+            const SizedBox(width: AppSpacing.sm),
+            Text(
+              value.toStringAsFixed(2),
+              style: AppTypography.mono(9.5).copyWith(
+                fontWeight: bold ? FontWeight.w700 : FontWeight.w400,
+                color: AppColors.textPrimary,
+              ),
+            ),
+          ],
         ),
       );
 
   Widget _bold(String text, {TextAlign align = TextAlign.left}) => Text(
         text,
         textAlign: align,
-        style: AppTypography.mono(11.5).copyWith(
+        maxLines: 1,
+        overflow: TextOverflow.clip,
+        style: AppTypography.mono(8.5).copyWith(
           fontWeight: FontWeight.w700,
           color: AppColors.textPrimary,
         ),
       );
+
+  Widget _cell(String text, {TextAlign align = TextAlign.left}) => Text(
+        text,
+        textAlign: align,
+        maxLines: 1,
+        overflow: TextOverflow.ellipsis,
+        style: AppTypography.mono(8.5),
+      );
+}
+
+/// One GST rate's slice of the bill, for the preview.
+class _PreviewSlab {
+  const _PreviewSlab(this.index, this.rate, this.lines, this.factor);
+
+  final int index;
+  final double rate;
+  final List<CartLine> lines;
+  final double factor;
+
+  String get halfPercent => '${(rate * 100 / 2).toStringAsFixed(2)}%';
+
+  double get total => lines.fold(0.0, (s, l) => s + l.payable * factor);
+
+  double get taxAmount => lines.fold(0.0, (s, l) => s + l.taxAmount * factor);
+
+  double get taxable => total - taxAmount;
+
+  double get cgst => taxAmount / 2;
+
+  double get sgst => taxAmount - cgst;
 }
 
 class _Dashes extends StatelessWidget {

lib/presentation/sync/providers/sync_controller.dart

@@ -80,6 +80,9 @@ class CatalogueImportController extends StateNotifier<ImportState> {
     state = ImportFailed(event.error ?? 'Import failed.');
     return false;
   }
+
+  /// Drops a stale success or failure banner.
+  void reset() => state = const ImportIdle();
 }
 
 final catalogueImportProvider =

linux/flutter/generated_plugin_registrant.cc

@@ -8,6 +8,7 @@
 
 #include <audioplayers_linux/audioplayers_linux_plugin.h>
 #include <printing/printing_plugin.h>
+#include <url_launcher_linux/url_launcher_plugin.h>
 
 void fl_register_plugins(FlPluginRegistry* registry) {
   g_autoptr(FlPluginRegistrar) audioplayers_linux_registrar =
@@ -16,4 +17,7 @@ void fl_register_plugins(FlPluginRegistry* registry) {
   g_autoptr(FlPluginRegistrar) printing_registrar =
       fl_plugin_registry_get_registrar_for_plugin(registry, "PrintingPlugin");
   printing_plugin_register_with_registrar(printing_registrar);
+  g_autoptr(FlPluginRegistrar) url_launcher_linux_registrar =
+      fl_plugin_registry_get_registrar_for_plugin(registry, "UrlLauncherPlugin");
+  url_launcher_plugin_register_with_registrar(url_launcher_linux_registrar);
 }

linux/flutter/generated_plugins.cmake

@@ -5,6 +5,7 @@
 list(APPEND FLUTTER_PLUGIN_LIST
   audioplayers_linux
   printing
+  url_launcher_linux
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST

macos/Flutter/GeneratedPluginRegistrant.swift

@@ -8,9 +8,11 @@ import Foundation
 import audioplayers_darwin
 import printing
 import sqflite_darwin
+import url_launcher_macos
 
 func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   AudioplayersDarwinPlugin.register(with: registry.registrar(forPlugin: "AudioplayersDarwinPlugin"))
   PrintingPlugin.register(with: registry.registrar(forPlugin: "PrintingPlugin"))
   SqflitePlugin.register(with: registry.registrar(forPlugin: "SqflitePlugin"))
+  UrlLauncherPlugin.register(with: registry.registrar(forPlugin: "UrlLauncherPlugin"))
 }

pubspec.lock

@@ -300,10 +300,10 @@ packages:
     dependency: transitive
     description:
       name: jni
-      sha256: "5bc9a9daac5ccfbd6a758377600b9f7fdce13d93f26e8012a8941014a5d978d1"
+      sha256: f038e58b4dc2c9037f50e233175086337e0b305e356d28211bf55f21c504cbd3
       url: "https://pub.dev"
     source: hosted
-    version: "1.0.2"
+    version: "1.0.3"
   jni_flutter:
     dependency: transitive
     description:
@@ -693,6 +693,70 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.4.0"
+  url_launcher:
+    dependency: "direct main"
+    description:
+      name: url_launcher
+      sha256: f6a7e5c4835bb4e3026a04793a4199ca2d14c739ec378fdfe23fc8075d0439f8
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.2"
+  url_launcher_android:
+    dependency: transitive
+    description:
+      name: url_launcher_android
+      sha256: b413d49b73867ac08dd2f9890efd3cc11f2a0e577618d50843440a1fb3776c32
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.32"
+  url_launcher_ios:
+    dependency: transitive
+    description:
+      name: url_launcher_ios
+      sha256: "580fe5dfb51671ae38191d316e027f6b76272b026370708c2d898799750a02b0"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.4.1"
+  url_launcher_linux:
+    dependency: transitive
+    description:
+      name: url_launcher_linux
+      sha256: d5e14138b3bc193a0f63c10a53c94b91d399df0512b1f29b94a043db7482384a
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.2"
+  url_launcher_macos:
+    dependency: transitive
+    description:
+      name: url_launcher_macos
+      sha256: "368adf46f71ad3c21b8f06614adb38346f193f3a59ba8fe9a2fd74133070ba18"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.5"
+  url_launcher_platform_interface:
+    dependency: transitive
+    description:
+      name: url_launcher_platform_interface
+      sha256: "552f8a1e663569be95a8190206a38187b531910283c3e982193e4f2733f01029"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.2"
+  url_launcher_web:
+    dependency: transitive
+    description:
+      name: url_launcher_web
+      sha256: "85c81589622fbc87c1c683aaea164d3604a7777495a79d91e39ffcdec39ddb34"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.3"
+  url_launcher_windows:
+    dependency: transitive
+    description:
+      name: url_launcher_windows
+      sha256: "712c70ab1b99744ff066053cbe3e80c73332b38d46e5e945c98689b2e66fc15f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.5"
   uuid:
     dependency: "direct main"
     description:

pubspec.yaml

@@ -32,6 +32,9 @@ dependencies:
   sqflite_common_ffi: ^2.3.3
   path: ^1.9.0
 
+  # Sharing the bill to WhatsApp
+  url_launcher: ^6.3.0
+
   # Peripherals: scanner beeps and thermal receipt printing
   audioplayers: ^6.0.0
   pdf: ^3.11.0

windows/flutter/generated_plugin_registrant.cc

@@ -8,10 +8,13 @@
 
 #include <audioplayers_windows/audioplayers_windows_plugin.h>
 #include <printing/printing_plugin.h>
+#include <url_launcher_windows/url_launcher_windows.h>
 
 void RegisterPlugins(flutter::PluginRegistry* registry) {
   AudioplayersWindowsPluginRegisterWithRegistrar(
       registry->GetRegistrarForPlugin("AudioplayersWindowsPlugin"));
   PrintingPluginRegisterWithRegistrar(
       registry->GetRegistrarForPlugin("PrintingPlugin"));
+  UrlLauncherWindowsRegisterWithRegistrar(
+      registry->GetRegistrarForPlugin("UrlLauncherWindows"));
 }

windows/flutter/generated_plugins.cmake

@@ -5,6 +5,7 @@
 list(APPEND FLUTTER_PLUGIN_LIST
   audioplayers_windows
   printing
+  url_launcher_windows
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST