improve parsing 2

lib/models/ocr_element.dart

@@ -0,0 +1,38 @@
+/// One OCR text fragment with pixel bounding box on the receipt image.
+library;
+
+class OcrElement {
+  const OcrElement({
+    required this.text,
+    required this.left,
+    required this.top,
+    required this.right,
+    required this.bottom,
+  });
+
+  final String text;
+  final double left;
+  final double top;
+  final double right;
+  final double bottom;
+
+  double get centerX => (left + right) / 2;
+  double get centerY => (top + bottom) / 2;
+  double get height => (bottom - top).abs();
+  double get width => (right - left).abs();
+}
+
+/// All positioned elements from one ML Kit recognition pass.
+class OcrDocument {
+  const OcrDocument({
+    required this.elements,
+    required this.imageWidth,
+    required this.imageHeight,
+    required this.flattenedText,
+  });
+
+  final List<OcrElement> elements;
+  final double imageWidth;
+  final double imageHeight;
+  final String flattenedText;
+}

lib/models/receipt_bounds.dart

@@ -0,0 +1,57 @@
+/// Normalized rectangle (0–1) on the receipt photo for review highlights.
+library;
+
+class ReceiptBounds {
+  const ReceiptBounds({
+    required this.left,
+    required this.top,
+    required this.right,
+    required this.bottom,
+  });
+
+  final double left;
+  final double top;
+  final double right;
+  final double bottom;
+
+  bool get isEmpty => right <= left || bottom <= top;
+
+  ReceiptBounds union(ReceiptBounds other) {
+    if (isEmpty) return other;
+    if (other.isEmpty) return this;
+    return ReceiptBounds(
+      left: left < other.left ? left : other.left,
+      top: top < other.top ? top : other.top,
+      right: right > other.right ? right : other.right,
+      bottom: bottom > other.bottom ? bottom : other.bottom,
+    );
+  }
+
+  static ReceiptBounds? merge(Iterable<ReceiptBounds> bounds) {
+    ReceiptBounds? merged;
+    for (final box in bounds) {
+      if (box.isEmpty) continue;
+      merged = merged == null ? box : merged.union(box);
+    }
+    return merged;
+  }
+
+  static ReceiptBounds fromPixelRect({
+    required double left,
+    required double top,
+    required double right,
+    required double bottom,
+    required double imageWidth,
+    required double imageHeight,
+  }) {
+    if (imageWidth <= 0 || imageHeight <= 0) {
+      return const ReceiptBounds(left: 0, top: 0, right: 0, bottom: 0);
+    }
+    return ReceiptBounds(
+      left: left / imageWidth,
+      top: top / imageHeight,
+      right: right / imageWidth,
+      bottom: bottom / imageHeight,
+    );
+  }
+}

lib/models/receipt_row.dart

@@ -0,0 +1,39 @@
+/// One visually reconstructed receipt row from clustered OCR elements.
+library;
+
+import 'ocr_element.dart';
+import 'receipt_bounds.dart';
+
+enum ReceiptRowKind {
+  skip,
+  quantityModifier,
+  nameOnly,
+  item,
+  discount,
+  grandTotal,
+  totalDiscount,
+}
+
+class ReceiptRow {
+  const ReceiptRow({
+    required this.kind,
+    required this.text,
+    required this.nameText,
+    this.price,
+    this.quantity,
+    this.unitPrice,
+    this.lineTotal,
+    this.elements = const [],
+    this.bounds,
+  });
+
+  final ReceiptRowKind kind;
+  final String text;
+  final String nameText;
+  final double? price;
+  final int? quantity;
+  final double? unitPrice;
+  final double? lineTotal;
+  final List<OcrElement> elements;
+  final ReceiptBounds? bounds;
+}