third commit

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';
 }