added categories, import export, settings

lib/models/shop.dart

@@ -0,0 +1,63 @@
+/// A confirmed shopping trip saved from a receipt.
+library;
+
+class Shop {
+  const Shop({
+    required this.id,
+    required this.supermarket,
+    required this.shoppedAt,
+    required this.total,
+    required this.itemCount,
+    this.receiptImagePath,
+  });
+
+  final int id;
+  final String supermarket;
+  final DateTime shoppedAt;
+  final double total;
+  final int itemCount;
+  final String? receiptImagePath;
+
+  factory Shop.fromMap(Map<String, Object?> map) {
+    return Shop(
+      id: map['id']! as int,
+      supermarket: map['supermarket']! as String,
+      shoppedAt: DateTime.parse(map['shopped_at']! as String),
+      total: (map['total']! as num).toDouble(),
+      itemCount: (map['item_count'] as num?)?.toInt() ?? 0,
+      receiptImagePath: map['receipt_image_path'] as String?,
+    );
+  }
+}
+
+class ShopItem {
+  const ShopItem({
+    required this.id,
+    required this.shopId,
+    required this.productId,
+    required this.name,
+    required this.price,
+    this.quantity,
+    this.unitPrice,
+  });
+
+  final int id;
+  final int shopId;
+  final int productId;
+  final String name;
+  final double price;
+  final int? quantity;
+  final double? unitPrice;
+
+  factory ShopItem.fromMap(Map<String, Object?> map) {
+    return ShopItem(
+      id: map['id']! as int,
+      shopId: map['shop_id']! as int,
+      productId: map['product_id']! as int,
+      name: map['name']! as String,
+      price: (map['price']! as num).toDouble(),
+      quantity: map['quantity'] as int?,
+      unitPrice: (map['unit_price'] as num?)?.toDouble(),
+    );
+  }
+}