fix(client): 标签打印布局与字号优化

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.0.41] - 2026-06-15
+
+### 改进
+- 标签打印布局优化：编号字体与度数/日期统一大小，内容整体下移并填满标签底部，店名适当放大
+- 标签度数与规格之间加宽间距，两个字段更易区分
+
 ## [1.0.40] - 2026-06-15
 
 ### 新功能

client/lib/core/utils/print_util_stub.dart

@@ -224,26 +224,38 @@ Future<ui.Image> _renderLabelBitmap({
   // 扫码溯源：居中于二维码正下方
   _drawText(canvas, '扫码溯源', qrLeft, qrTop + qrS + 2, 14, qrS, center: true);
 
-  // 左侧文字（无字段名标签）：按行等比分配高度铺满，字号自适应填充
+  // 左侧文字：固定字号 + 自适应行间距（与二维码上下对齐，行距均匀分配剩余空间）
   const lx = 22.0;
   const textMaxW = qrLeft - lx - 6; // 164
+
+  // 字号固定：只有商品名按宽度自适应，其余行均固定，杜绝自动放大
+  const double kShopSize  = 17.0; // 酒行名，粗体
+  const double kSmallSize = 13.0; // 编号 / 度数 / 日期，统一小字
+  // 商品名：仅按宽度适配，上限 26px，下限 14px
+  final double nameSize = _fitFont(name, textMaxW, 1000, true, 26.0).clamp(14.0, 26.0);
+
   final codeText = code.isNotEmpty ? '编号：$code' : '';
   final rows = <(String, double, bool)>[
-    (shop, 0.9, true),
+    if (shop.isNotEmpty)     (shop,    kShopSize,  true),
-    (name, 1.5, true),
+    if (name.isNotEmpty)     (name,    nameSize,   true),
-    if (codeText.isNotEmpty) (codeText, 1.0, false),
+    if (codeText.isNotEmpty) (codeText, kSmallSize, false),
-    if (degSpec.isNotEmpty) (degSpec, 1.05, false),
+    if (degSpec.isNotEmpty)  (degSpec,  kSmallSize, false),
-    if (date.isNotEmpty) (date, 1.0, false),
+    if (date.isNotEmpty)     (date,     kSmallSize, false),
   ];
-  const topY = 4.0, botY = 156.0;
+
-  final totalWeight = rows.fold<double>(0, (a, r) => a + r.$2);
+  // 文字区域：整体略低于二维码顶部，底部延伸至扫码溯源文字下方
-  double yy = topY;
+  const double kTextTop = 16.0; // 比二维码顶部(8)低一些，整体下移
+  const double kTextBot = 150.0; // 延伸至底部，减少留白
+  const double kLineH   = 1.35;         // 行高倍数（字号 × 行高 = 该行占用高度）
+  final double totalTextH = rows.fold(0.0, (s, r) => s + r.$2 * kLineH);
+  final int n = rows.length;
+  final double rawGap = n > 0 ? (kTextBot - kTextTop - totalTextH) / (n + 1) : 4.0;
+  final double gap = rawGap < 1.5 ? 1.5 : rawGap;
+
+  double yy = kTextTop + gap;
   for (final r in rows) {
-    final rowH = (botY - topY) * r.$2 / totalWeight;
+    _drawText(canvas, r.$1, lx, yy, r.$2, textMaxW, bold: r.$3);
-    final fs = _fitFont(r.$1, textMaxW, rowH * 0.84, r.$3, 30);
+    yy += r.$2 * kLineH + gap;
-    final ty = yy + (rowH - fs * 1.25) / 2;
-    _drawText(canvas, r.$1, lx, ty < yy ? yy : ty, fs, textMaxW, bold: r.$3);
-    yy += rowH;
   }
 
   return recorder.endRecording().toImage(w, h);
@@ -327,7 +339,7 @@ Future<void> printProductLabelImpl({
   final specVal   = (spec ?? '').isNotEmpty ? spec! : '';
   final seriesVal = (series ?? '').isNotEmpty ? series! : '';
   // 度数(系列) + 规格 同一行
-  final degSpecVal = [seriesVal, specVal].where((s) => s.isNotEmpty).join(' ');
+  final degSpecVal = [seriesVal, specVal].where((s) => s.isNotEmpty).join('    ');
   final dateVal   = (productionDate ?? '').isNotEmpty
       ? (productionDate!.length > 10 ? productionDate.substring(0, 10) : productionDate)
       : '—';
@@ -484,7 +496,7 @@ Future<void> printProductLabelImpl({
 Future<Uint8List> renderLabelPreviewImpl(LabelData label) async {
   final specVal = (label.spec ?? '').isNotEmpty ? label.spec! : '';
   final seriesVal = (label.series ?? '').isNotEmpty ? label.series! : '';
-  final degSpecVal = [seriesVal, specVal].where((s) => s.isNotEmpty).join(' ');
+  final degSpecVal = [seriesVal, specVal].where((s) => s.isNotEmpty).join('    ');
   final dateVal = (label.productionDate ?? '').isNotEmpty
       ? (label.productionDate!.length > 10
           ? label.productionDate!.substring(0, 10)