refactor: extract boxing logic into dedicated modules with tests

- boxing_models.dart: add BoxingMode, BoxingPhase, BoxingPageArguments
- boxing_box_mutations.dart: box item add/replace/remove operations
- boxing_calculations.dart: pure calculation helpers (quantities, validation)
- boxing_status_presenter.dart: status bar text/dot determination
- dialogs/cross_paichan_dialog.dart: cross-paichan confirmation dialog
- widgets/boxing_notice_banners.dart: notice banner widgets
- Add unit tests for mutations, calculations, and status presenter

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

lib/pages/boxing/boxing_box_mutations.dart

@@ -0,0 +1,135 @@
+import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+import 'package:pad_scanner/services/api_service.dart';
+
+class BoxMutationResult {
+  final List<BoxDetailData> boxes;
+  final int maxBoxNo;
+
+  const BoxMutationResult({required this.boxes, required this.maxBoxNo});
+}
+
+int maxBoxNoFor(List<BoxDetailData> boxes) {
+  return boxes.fold<int>(0, (max, box) => box.boxNo > max ? box.boxNo : max);
+}
+
+BoxMutationResult addExistingBoxItem({
+  required List<BoxDetailData> existingBoxes,
+  required int boxNo,
+  required int quantity,
+  required int? boxItemId,
+  required String zongpaiNo,
+  required String? workOrderNo,
+  required int? totalQuantity,
+}) {
+  final item = BoxItemData(
+    boxItemId: boxItemId,
+    zongpaiNo: zongpaiNo,
+    workOrderNo: workOrderNo,
+    quantity: quantity,
+    totalQuantity: totalQuantity,
+  );
+  final index = existingBoxes.indexWhere((box) => box.boxNo == boxNo);
+  if (index < 0) {
+    final boxes = [
+      ...existingBoxes,
+      BoxDetailData(boxNo: boxNo, items: [item]),
+    ]..sort((a, b) => a.boxNo.compareTo(b.boxNo));
+    return BoxMutationResult(boxes: boxes, maxBoxNo: maxBoxNoFor(boxes));
+  }
+
+  final boxes = List<BoxDetailData>.from(existingBoxes);
+  final box = boxes[index];
+  boxes[index] = BoxDetailData(boxNo: box.boxNo, items: [...box.items, item]);
+  return BoxMutationResult(boxes: boxes, maxBoxNo: maxBoxNoFor(boxes));
+}
+
+BoxMutationResult replaceExistingBoxItem({
+  required List<BoxDetailData> existingBoxes,
+  required CurrentZongpaiBoxData editing,
+  required int boxNo,
+  required int quantity,
+  required String zongpaiNo,
+  required String? workOrderNo,
+  required int? totalQuantity,
+}) {
+  final updatedItem = BoxItemData(
+    boxItemId: editing.boxItemId,
+    zongpaiNo: zongpaiNo,
+    workOrderNo: workOrderNo,
+    quantity: quantity,
+    totalQuantity: totalQuantity,
+  );
+  return _replaceItemById(
+    existingBoxes: existingBoxes,
+    boxItemId: editing.boxItemId,
+    targetBoxNo: boxNo,
+    updatedItem: updatedItem,
+  );
+}
+
+BoxMutationResult replaceExistingPackedItem({
+  required List<BoxDetailData> existingBoxes,
+  required ManyToOnePackedItem item,
+  required int boxNo,
+  required int quantity,
+}) {
+  final updatedItem = BoxItemData(
+    boxItemId: item.boxItemId,
+    zongpaiNo: item.zongpaiNo,
+    workOrderNo: item.workOrderNo,
+    quantity: quantity,
+    totalQuantity: item.totalQuantity,
+  );
+  return _replaceItemById(
+    existingBoxes: existingBoxes,
+    boxItemId: item.boxItemId,
+    targetBoxNo: boxNo,
+    updatedItem: updatedItem,
+  );
+}
+
+BoxMutationResult removeExistingBoxItem({
+  required List<BoxDetailData> existingBoxes,
+  required int boxItemId,
+}) {
+  final boxes = <BoxDetailData>[];
+  for (final box in existingBoxes) {
+    final items = box.items
+        .where((item) => item.boxItemId != boxItemId)
+        .toList();
+    if (items.isNotEmpty) {
+      boxes.add(BoxDetailData(boxNo: box.boxNo, items: items));
+    }
+  }
+  return BoxMutationResult(boxes: boxes, maxBoxNo: maxBoxNoFor(boxes));
+}
+
+BoxMutationResult _replaceItemById({
+  required List<BoxDetailData> existingBoxes,
+  required int boxItemId,
+  required int targetBoxNo,
+  required BoxItemData updatedItem,
+}) {
+  final boxes = <BoxDetailData>[];
+  for (final box in existingBoxes) {
+    final items = box.items.where((item) {
+      return item.boxItemId != boxItemId;
+    }).toList();
+    if (items.isNotEmpty) {
+      boxes.add(BoxDetailData(boxNo: box.boxNo, items: items));
+    }
+  }
+
+  final targetIndex = boxes.indexWhere((box) => box.boxNo == targetBoxNo);
+  if (targetIndex >= 0) {
+    final target = boxes[targetIndex];
+    boxes[targetIndex] = BoxDetailData(
+      boxNo: target.boxNo,
+      items: [...target.items, updatedItem],
+    );
+  } else {
+    boxes.add(BoxDetailData(boxNo: targetBoxNo, items: [updatedItem]));
+  }
+  boxes.sort((a, b) => a.boxNo.compareTo(b.boxNo));
+  return BoxMutationResult(boxes: boxes, maxBoxNo: maxBoxNoFor(boxes));
+}

lib/pages/boxing/boxing_calculations.dart

@@ -0,0 +1,101 @@
+import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+import 'package:pad_scanner/services/api_service.dart';
+
+int packedQuantity(List<CurrentZongpaiBoxData> items) {
+  return items.fold<int>(0, (sum, item) => sum + item.quantity);
+}
+
+int remainingQuantity({
+  required int? totalQuantity,
+  required List<CurrentZongpaiBoxData> currentBoxes,
+}) {
+  return (totalQuantity ?? 0) - packedQuantity(currentBoxes);
+}
+
+bool quantityTooHigh({
+  required int remainingQuantity,
+  required String quantityText,
+}) {
+  if (remainingQuantity <= 0) return false;
+  final quantity = int.tryParse(quantityText);
+  return quantity != null && quantity > remainingQuantity;
+}
+
+bool canSubmitBoxing({
+  required bool isSubmitting,
+  required BoxingPhase phase,
+  required String? zongpaiNo,
+  required String boxNoText,
+  required String quantityText,
+  required int remainingQuantity,
+  required bool quantityTooHigh,
+  required bool isDuplicateBoxNo,
+}) {
+  if (isSubmitting || phase != BoxingPhase.scanned) return false;
+  if (zongpaiNo == null) return false;
+  final boxNo = int.tryParse(boxNoText);
+  final quantity = int.tryParse(quantityText);
+  if (boxNo == null || boxNo <= 0 || quantity == null || quantity <= 0) {
+    return false;
+  }
+  if (remainingQuantity <= 0) return false;
+  if (quantityTooHigh) return false;
+  if (isDuplicateBoxNo) return false;
+  return true;
+}
+
+int? currentManyToOneBoxNo(String boxNoText) {
+  final boxNo = int.tryParse(boxNoText.trim());
+  if (boxNo == null || boxNo <= 0) return null;
+  return boxNo;
+}
+
+bool singleCodeBoxNoIsDuplicate({
+  required String boxNoText,
+  required List<CurrentZongpaiBoxData> currentBoxes,
+  required int? editingBoxItemId,
+}) {
+  final boxNo = int.tryParse(boxNoText);
+  if (boxNo == null) return false;
+  return currentBoxes.any((box) {
+    if (box.boxNo != boxNo) return false;
+    return editingBoxItemId == null || box.boxItemId != editingBoxItemId;
+  });
+}
+
+List<ManyToOnePackedItem> visibleManyToOnePackedItems({
+  required int? boxNo,
+  required List<BoxDetailData> existingBoxes,
+  required List<ManyToOnePackedItem> packedItems,
+  required String? paichanNo,
+}) {
+  if (boxNo == null) return const [];
+  final byItemId = <int, ManyToOnePackedItem>{};
+  for (final box in existingBoxes.where((box) => box.boxNo == boxNo)) {
+    for (final item in box.items) {
+      final boxItemId = item.boxItemId;
+      if (boxItemId == null) continue;
+      byItemId[boxItemId] = ManyToOnePackedItem(
+        boxItemId: boxItemId,
+        zongpaiNo: item.zongpaiNo,
+        paichanNo: paichanNo,
+        workOrderNo: item.workOrderNo,
+        boxNo: boxNo,
+        quantity: item.quantity,
+        totalQuantity: item.totalQuantity,
+      );
+    }
+  }
+  for (final item in packedItems.where((item) => item.boxNo == boxNo)) {
+    byItemId[item.boxItemId] = item;
+  }
+  return byItemId.values.toList(growable: false);
+}
+
+int maxAssignedQuantity({
+  required int? totalQuantity,
+  required int packedQuantity,
+  required int itemQuantity,
+}) {
+  return (totalQuantity ?? 0) - (packedQuantity - itemQuantity);
+}

lib/pages/boxing/boxing_models.dart

@@ -1,3 +1,24 @@
+enum BoxingMode {
+  singleCode, // 单码装箱
+  multiCode, // 多码凑箱
+}
+
+enum BoxingPhase {
+  waiting, // 等待扫码
+  scanned, // 已扫码，显示信息
+  submitted, // 已提交成功
+}
+
+class BoxingPageArguments {
+  final BoxingMode initialMode;
+  final List<String> autoScanCodes;
+
+  const BoxingPageArguments({
+    required this.initialMode,
+    required this.autoScanCodes,
+  });
+}
+
 class ManyToOnePackedItem {
   final int boxItemId;
   final String zongpaiNo;

lib/pages/boxing/boxing_status_presenter.dart

@@ -0,0 +1,97 @@
+import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+import 'package:pad_scanner/widgets/status_bar.dart';
+
+class BoxingStatusPresentation {
+  final StatusDotColor dot;
+  final String text;
+
+  const BoxingStatusPresentation({required this.dot, required this.text});
+}
+
+BoxingStatusPresentation boxingStatusFor({
+  required bool isAutoProcessing,
+  required bool isSubmitting,
+  required bool isDuplicateBoxNo,
+  required bool quantityTooHigh,
+  required bool isEditingAssigned,
+  required bool isDeletingAssigned,
+  required bool hasPaichanSwitchNotice,
+  required BoxingPhase phase,
+  required bool isMultiCode,
+  required bool hasVisibleManyToOneItems,
+  required int remainingQuantity,
+  required String boxNoText,
+}) {
+  if (isAutoProcessing) {
+    return const BoxingStatusPresentation(
+      dot: StatusDotColor.orange,
+      text: '正在同步转运数据...',
+    );
+  }
+  if (isSubmitting) {
+    return const BoxingStatusPresentation(
+      dot: StatusDotColor.orange,
+      text: '正在提交…',
+    );
+  }
+  if (isDuplicateBoxNo && phase == BoxingPhase.scanned) {
+    return BoxingStatusPresentation(
+      dot: StatusDotColor.amber,
+      text: '箱号 $boxNoText 已存在，请重新输入',
+    );
+  }
+  if (quantityTooHigh && phase == BoxingPhase.scanned) {
+    return const BoxingStatusPresentation(
+      dot: StatusDotColor.red,
+      text: '超出可装数量上限',
+    );
+  }
+  if (isEditingAssigned) {
+    return const BoxingStatusPresentation(
+      dot: StatusDotColor.amber,
+      text: '正在编辑已分配记录',
+    );
+  }
+  if (isDeletingAssigned) {
+    return const BoxingStatusPresentation(
+      dot: StatusDotColor.red,
+      text: '请确认是否删除该箱记录',
+    );
+  }
+  if (hasPaichanSwitchNotice) {
+    return const BoxingStatusPresentation(
+      dot: StatusDotColor.blue,
+      text: '排产号已切换，箱号已重置',
+    );
+  }
+
+  switch (phase) {
+    case BoxingPhase.waiting:
+      if (isMultiCode && hasVisibleManyToOneItems) {
+        return const BoxingStatusPresentation(
+          dot: StatusDotColor.blue,
+          text: '请继续扫码或完成本箱',
+        );
+      }
+      return const BoxingStatusPresentation(
+        dot: StatusDotColor.blue,
+        text: '等待扫码',
+      );
+    case BoxingPhase.scanned:
+      if (remainingQuantity <= 0) {
+        return const BoxingStatusPresentation(
+          dot: StatusDotColor.red,
+          text: '该总排号已全部装箱完毕',
+        );
+      }
+      return const BoxingStatusPresentation(
+        dot: StatusDotColor.blue,
+        text: '数量已填入，请确认或修改',
+      );
+    case BoxingPhase.submitted:
+      return BoxingStatusPresentation(
+        dot: StatusDotColor.green,
+        text: isMultiCode ? '请扫描下一个总排号' : '装箱成功，可继续扫码',
+      );
+  }
+}

lib/pages/boxing/dialogs/cross_paichan_dialog.dart

@@ -0,0 +1,126 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+Future<bool> showCrossPaichanDialog({
+  required BuildContext context,
+  required String currentPaicha,
+  required String newPaicha,
+}) async {
+  final dialogFocus = FocusNode();
+  var selectedIndex = 0; // 0 = "否" (default), 1 = "是"
+
+  final dialogFuture = showDialog<bool>(
+    context: context,
+    barrierDismissible: false,
+    builder: (ctx) => StatefulBuilder(
+      builder: (ctx, setDialogState) {
+        void dismissAsNo() => Navigator.of(ctx).pop(false);
+        void confirmSwitch() => Navigator.of(ctx).pop(true);
+
+        return KeyboardListener(
+          focusNode: dialogFocus,
+          onKeyEvent: (event) {
+            if (event is! KeyDownEvent) return;
+            if (event.logicalKey == LogicalKeyboardKey.arrowUp) {
+              setDialogState(() => selectedIndex = 0);
+            } else if (event.logicalKey == LogicalKeyboardKey.arrowDown) {
+              setDialogState(() => selectedIndex = 1);
+            } else if (event.logicalKey == LogicalKeyboardKey.enter) {
+              selectedIndex == 0 ? dismissAsNo() : confirmSwitch();
+            } else if (event.logicalKey == LogicalKeyboardKey.escape) {
+              dismissAsNo();
+            }
+          },
+          child: PopScope(
+            canPop: false,
+            onPopInvokedWithResult: (didPop, _) {
+              if (!didPop) dismissAsNo();
+            },
+            child: AlertDialog(
+              backgroundColor: Colors.orange.shade50,
+              title: Row(
+                children: [
+                  Icon(Icons.warning_amber, color: Colors.orange.shade800),
+                  const SizedBox(width: 8),
+                  Text(
+                    '跨排产号扫描',
+                    style: TextStyle(color: Colors.orange.shade900),
+                  ),
+                ],
+              ),
+              content: Column(
+                mainAxisSize: MainAxisSize.min,
+                crossAxisAlignment: CrossAxisAlignment.stretch,
+                children: [
+                  Text(
+                    '当前排产号：$currentPaicha\n'
+                    '新排产号：$newPaicha\n\n'
+                    '是否切换到新的排产号？\n\n'
+                    '选择「是」将放弃当前已扫描的所有数据。',
+                    style: const TextStyle(fontSize: 14),
+                  ),
+                  const SizedBox(height: 16),
+                  _DialogOptionButton(
+                    label: '否',
+                    selected: selectedIndex == 0,
+                    onTap: dismissAsNo,
+                  ),
+                  const SizedBox(height: 8),
+                  _DialogOptionButton(
+                    label: '是，切换排产号',
+                    selected: selectedIndex == 1,
+                    onTap: confirmSwitch,
+                  ),
+                ],
+              ),
+            ),
+          ),
+        );
+      },
+    ),
+  );
+
+  WidgetsBinding.instance.addPostFrameCallback((_) {
+    dialogFocus.requestFocus();
+  });
+
+  final result = await dialogFuture;
+  dialogFocus.dispose();
+  return result ?? false;
+}
+
+class _DialogOptionButton extends StatelessWidget {
+  final String label;
+  final bool selected;
+  final VoidCallback onTap;
+
+  const _DialogOptionButton({
+    required this.label,
+    required this.selected,
+    required this.onTap,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return SizedBox(
+      width: double.infinity,
+      height: 40,
+      child: ElevatedButton(
+        onPressed: onTap,
+        style: ElevatedButton.styleFrom(
+          backgroundColor: selected
+              ? Colors.blue.shade700
+              : Colors.grey.shade200,
+          foregroundColor: selected ? Colors.white : Colors.black87,
+          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
+        ),
+        child: Text(
+          label,
+          style: TextStyle(
+            fontWeight: selected ? FontWeight.w800 : FontWeight.w600,
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/pages/boxing/widgets/boxing_notice_banners.dart

@@ -0,0 +1,178 @@
+import 'package:flutter/material.dart';
+import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+
+class BoxingNoticeBanners extends StatelessWidget {
+  final bool isAutoProcessing;
+  final List<String> autoWarnings;
+  final String? paichanSwitchNotice;
+  final bool isDuplicateBoxNo;
+  final bool quantityTooHigh;
+  final BoxingPhase phase;
+  final String boxNoText;
+  final int remainingQuantity;
+  final String? zongpaiNo;
+  final int? completedJumpBoxNo;
+  final VoidCallback onJumpToCompletedBox;
+
+  const BoxingNoticeBanners({
+    super.key,
+    required this.isAutoProcessing,
+    required this.autoWarnings,
+    required this.paichanSwitchNotice,
+    required this.isDuplicateBoxNo,
+    required this.quantityTooHigh,
+    required this.phase,
+    required this.boxNoText,
+    required this.remainingQuantity,
+    required this.zongpaiNo,
+    required this.completedJumpBoxNo,
+    required this.onJumpToCompletedBox,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final banners = <Widget>[];
+    if (isAutoProcessing) {
+      banners.add(
+        _NoticeBanner(
+          icon: SizedBox(
+            width: 12,
+            height: 12,
+            child: CircularProgressIndicator(
+              strokeWidth: 1.5,
+              color: Colors.orange.shade700,
+            ),
+          ),
+          text: '正在同步转运数据...',
+          background: Colors.orange.shade50,
+          foreground: Colors.orange.shade900,
+          border: Colors.orange.shade100,
+        ),
+      );
+    }
+    if (autoWarnings.isNotEmpty) {
+      banners.add(
+        _NoticeBanner(
+          icon: Icon(
+            Icons.warning_amber,
+            size: 14,
+            color: Colors.amber.shade900,
+          ),
+          text: autoWarnings.join('；'),
+          background: Colors.amber.shade100,
+          foreground: Colors.amber.shade900,
+          border: Colors.amber.shade200,
+        ),
+      );
+    }
+    if (paichanSwitchNotice != null) {
+      banners.add(
+        _NoticeBanner(
+          icon: Icon(Icons.info_outline, size: 14, color: Colors.blue.shade900),
+          text: paichanSwitchNotice!,
+          background: Colors.blue.shade50,
+          foreground: Colors.blue.shade900,
+          border: Colors.blue.shade100,
+        ),
+      );
+    }
+    if (isDuplicateBoxNo && phase == BoxingPhase.scanned) {
+      banners.add(
+        _NoticeBanner(
+          icon: Icon(
+            Icons.warning_amber,
+            size: 14,
+            color: Colors.amber.shade900,
+          ),
+          text: '箱号 $boxNoText 已存在，请重新输入',
+          background: Colors.amber.shade100,
+          foreground: Colors.amber.shade900,
+          border: Colors.amber.shade200,
+        ),
+      );
+    }
+    if (quantityTooHigh && phase == BoxingPhase.scanned) {
+      banners.add(
+        _NoticeBanner(
+          icon: Icon(Icons.close, size: 14, color: Colors.red.shade800),
+          text: '超出可装数量上限（最多可装 $remainingQuantity 件）',
+          background: Colors.red.shade50,
+          foreground: Colors.red.shade800,
+          border: Colors.red.shade100,
+        ),
+      );
+    }
+    if (phase == BoxingPhase.scanned &&
+        zongpaiNo != null &&
+        remainingQuantity <= 0) {
+      final jumpBoxNo = completedJumpBoxNo;
+      if (jumpBoxNo != null) {
+        banners.add(
+          GestureDetector(
+            onTap: onJumpToCompletedBox,
+            behavior: HitTestBehavior.opaque,
+            child: _NoticeBanner(
+              icon: Icon(Icons.warning, size: 14, color: Colors.amber.shade800),
+              text: '$zongpaiNo 已完成装箱。(P4跳转所在箱号)',
+              background: Colors.amber.shade50,
+              foreground: Colors.amber.shade800,
+              border: Colors.amber.shade200,
+            ),
+          ),
+        );
+      } else {
+        banners.add(
+          _NoticeBanner(
+            icon: Icon(Icons.warning, size: 14, color: Colors.red.shade800),
+            text: '$zongpaiNo 已全部装箱完毕，无需操作',
+            background: Colors.red.shade50,
+            foreground: Colors.red.shade800,
+            border: Colors.red.shade100,
+          ),
+        );
+      }
+    }
+    return Column(mainAxisSize: MainAxisSize.min, children: banners);
+  }
+}
+
+class _NoticeBanner extends StatelessWidget {
+  final Widget icon;
+  final String text;
+  final Color background;
+  final Color foreground;
+  final Color border;
+
+  const _NoticeBanner({
+    required this.icon,
+    required this.text,
+    required this.background,
+    required this.foreground,
+    required this.border,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      width: double.infinity,
+      padding: const EdgeInsets.symmetric(vertical: 6, horizontal: 12),
+      decoration: BoxDecoration(
+        color: background,
+        border: Border(bottom: BorderSide(color: border)),
+      ),
+      child: Row(
+        children: [
+          icon,
+          const SizedBox(width: 6),
+          Expanded(
+            child: Text(
+              text,
+              style: TextStyle(fontSize: 12, color: foreground),
+              overflow: TextOverflow.ellipsis,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/pages/boxing_page.dart

@@ -8,37 +8,22 @@ import 'package:pad_scanner/services/code_parser.dart';
 import 'package:pad_scanner/services/api_service.dart';
 import 'package:pad_scanner/services/boxing_context.dart';
 import 'package:pad_scanner/services/feedback_service.dart';
+import 'package:pad_scanner/pages/boxing/boxing_box_mutations.dart'
+    as box_mutations;
+import 'package:pad_scanner/pages/boxing/boxing_calculations.dart'
+    as boxing_calculations;
 import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+import 'package:pad_scanner/pages/boxing/boxing_status_presenter.dart';
+import 'package:pad_scanner/pages/boxing/dialogs/cross_paichan_dialog.dart';
 import 'package:pad_scanner/pages/boxing/widgets/boxing_shared_widgets.dart';
+import 'package:pad_scanner/pages/boxing/widgets/boxing_notice_banners.dart';
 import 'package:pad_scanner/pages/boxing/widgets/multi_code_body.dart';
 import 'package:pad_scanner/pages/boxing/widgets/single_code_body.dart';
 import 'package:pad_scanner/pages/boxing_detail_page.dart';
 import 'package:pad_scanner/widgets/status_bar.dart';
 
-// === 装箱模式 ===
+export 'package:pad_scanner/pages/boxing/boxing_models.dart'
-
+    show BoxingMode, BoxingPageArguments;
-enum BoxingMode {
-  singleCode, // 单码装箱
-  multiCode, // 多码凑箱
-}
-
-class BoxingPageArguments {
-  final BoxingMode initialMode;
-  final List<String> autoScanCodes;
-
-  const BoxingPageArguments({
-    required this.initialMode,
-    required this.autoScanCodes,
-  });
-}
-
-// === 页面阶段 ===
-
-enum _Phase {
-  waiting, // 等待扫码
-  scanned, // 已扫码，显示信息
-  submitted, // 已提交成功
-}
 
 // === 主页面 ===
 
@@ -62,7 +47,7 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
   BoxingMode _mode = BoxingMode.singleCode;
 
   // 阶段
-  _Phase _phase = _Phase.waiting;
+  BoxingPhase _phase = BoxingPhase.waiting;
 
   // 当前总排号
   String? _zongpaiNo;
@@ -221,7 +206,7 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
   }
 
   void _resetState() {
-    _phase = _Phase.waiting;
+    _phase = BoxingPhase.waiting;
     _zongpaiNo = null;
     _paichanNo = null;
     _workOrderNo = null;
@@ -334,7 +319,7 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
       _currentZongpaiBoxes = result.currentZongpaiBoxes;
       _existingBoxes = result.existingBoxes;
       _maxBoxNo = result.maxBoxNo;
-      _phase = _Phase.scanned;
+      _phase = BoxingPhase.scanned;
       _isDuplicateBoxNo = false;
       _editingBox = null;
       _editingAssignedItemId = null;
@@ -469,98 +454,16 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
 
   // === 跨排产号确认对话框 ===
 
-  void _showCrossPaichaDialog() {
+  Future<void> _showCrossPaichaDialog() async {
     final currentPaicha = _lastScannedPaichanNo ?? '--';
     final newPaicha = _paichanNo ?? '--';
-    final dialogFocus = FocusNode();
+    final confirmed = await showCrossPaichanDialog(
-    var dismissed = false;
-    var selectedIndex = 0; // 0 = "否" (default), 1 = "是"
-
-    void dismissAsNo() {
-      if (dismissed) return;
-      dismissed = true;
-      Navigator.of(context).pop();
-      _cancelPaichanSwitch();
-    }
-
-    void confirmSwitch() {
-      if (dismissed) return;
-      dismissed = true;
-      Navigator.of(context).pop();
-      _confirmPaichanSwitch();
-    }
-
-    showDialog(
       context: context,
-      barrierDismissible: false,
+      currentPaicha: currentPaicha,
-      builder: (ctx) => StatefulBuilder(
+      newPaicha: newPaicha,
-        builder: (ctx, setDialogState) {
-          return KeyboardListener(
-            focusNode: dialogFocus,
-            onKeyEvent: (event) {
-              if (event is! KeyDownEvent) return;
-              if (event.logicalKey == LogicalKeyboardKey.arrowUp) {
-                setDialogState(() => selectedIndex = 0);
-              } else if (event.logicalKey == LogicalKeyboardKey.arrowDown) {
-                setDialogState(() => selectedIndex = 1);
-              } else if (event.logicalKey == LogicalKeyboardKey.enter) {
-                selectedIndex == 0 ? dismissAsNo() : confirmSwitch();
-              } else if (event.logicalKey == LogicalKeyboardKey.escape) {
-                dismissAsNo();
-              }
-            },
-            child: PopScope(
-              canPop: false,
-              onPopInvokedWithResult: (didPop, _) {
-                if (!didPop) dismissAsNo();
-              },
-              child: AlertDialog(
-                backgroundColor: Colors.orange.shade50,
-                title: Row(
-                  children: [
-                    Icon(Icons.warning_amber, color: Colors.orange.shade800),
-                    const SizedBox(width: 8),
-                    Text(
-                      '跨排产号扫描',
-                      style: TextStyle(color: Colors.orange.shade900),
-                    ),
-                  ],
-                ),
-                content: Column(
-                  mainAxisSize: MainAxisSize.min,
-                  crossAxisAlignment: CrossAxisAlignment.stretch,
-                  children: [
-                    Text(
-                      '当前排产号：$currentPaicha\n'
-                      '新排产号：$newPaicha\n\n'
-                      '是否切换到新的排产号？\n\n'
-                      '选择「是」将放弃当前已扫描的所有数据。',
-                      style: const TextStyle(fontSize: 14),
-                    ),
-                    const SizedBox(height: 16),
-                    _dialogOptionBtn(
-                      label: '否',
-                      selected: selectedIndex == 0,
-                      onTap: dismissAsNo,
-                    ),
-                    const SizedBox(height: 8),
-                    _dialogOptionBtn(
-                      label: '是，切换排产号',
-                      selected: selectedIndex == 1,
-                      onTap: confirmSwitch,
-                    ),
-                  ],
-                ),
-              ),
-            ),
-          );
-        },
-      ),
     );
-
+    if (!mounted) return;
-    WidgetsBinding.instance.addPostFrameCallback((_) {
+    confirmed ? _confirmPaichanSwitch() : _cancelPaichanSwitch();
-      dialogFocus.requestFocus();
-    });
   }
 
   void _confirmPaichanSwitch() {
@@ -609,50 +512,20 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
       _crossPaichaPending = false;
       _zongpaiNo = null;
       _paichanNo = _lastScannedPaichanNo;
-      _phase = _Phase.waiting;
+      _phase = BoxingPhase.waiting;
     });
   }
 
-  Widget _dialogOptionBtn({
-    required String label,
-    required bool selected,
-    required VoidCallback onTap,
-  }) {
-    return SizedBox(
-      width: double.infinity,
-      height: 40,
-      child: ElevatedButton(
-        onPressed: onTap,
-        style: ElevatedButton.styleFrom(
-          backgroundColor: selected
-              ? Colors.blue.shade700
-              : Colors.grey.shade200,
-          foregroundColor: selected ? Colors.white : Colors.black87,
-          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
-        ),
-        child: Text(
-          label,
-          style: TextStyle(
-            fontWeight: selected ? FontWeight.w800 : FontWeight.w600,
-          ),
-        ),
-      ),
-    );
-  }
-
   // === 重复箱号检测 ===
 
   bool _boxNoIsDuplicate() {
-    final boxNo = int.tryParse(_boxNoController.text);
-    if (boxNo == null) {
-      return false;
-    }
     return switch (_mode) {
       BoxingMode.multiCode => false,
-      BoxingMode.singleCode => _currentZongpaiBoxes.any((b) {
+      BoxingMode.singleCode => boxing_calculations.singleCodeBoxNoIsDuplicate(
-        if (b.boxNo != boxNo) return false;
+        boxNoText: _boxNoController.text,
-        return _editingBox == null || b.boxItemId != _editingBox!.boxItemId;
+        currentBoxes: _currentZongpaiBoxes,
-      }),
+        editingBoxItemId: _editingBox?.boxItemId,
+      ),
     };
   }
 
@@ -663,33 +536,34 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
   // === 提交 ===
 
   int get _packedQuantity {
-    return _currentZongpaiBoxes.fold<int>(
+    return boxing_calculations.packedQuantity(_currentZongpaiBoxes);
-      0,
-      (sum, item) => sum + item.quantity,
-    );
   }
 
   int get _remainingQuantity {
-    final total = _erpQuantity ?? 0;
+    return boxing_calculations.remainingQuantity(
-    return total - _packedQuantity;
+      totalQuantity: _erpQuantity,
+      currentBoxes: _currentZongpaiBoxes,
+    );
   }
 
   bool get _quantityTooHigh {
-    if (_remainingQuantity <= 0) return false;
+    return boxing_calculations.quantityTooHigh(
-    final qty = int.tryParse(_quantityController.text);
+      remainingQuantity: _remainingQuantity,
-    return qty != null && qty > _remainingQuantity;
+      quantityText: _quantityController.text,
+    );
   }
 
   bool get _canSubmit {
-    if (_isSubmitting || _phase != _Phase.scanned) return false;
+    return boxing_calculations.canSubmitBoxing(
-    if (_zongpaiNo == null) return false;
+      isSubmitting: _isSubmitting,
-    final boxNo = int.tryParse(_boxNoController.text);
+      phase: _phase,
-    final qty = int.tryParse(_quantityController.text);
+      zongpaiNo: _zongpaiNo,
-    if (boxNo == null || boxNo <= 0 || qty == null || qty <= 0) return false;
+      boxNoText: _boxNoController.text,
-    if (_remainingQuantity <= 0) return false;
+      quantityText: _quantityController.text,
-    if (_quantityTooHigh) return false;
+      remainingQuantity: _remainingQuantity,
-    if (_isDuplicateBoxNo) return false;
+      quantityTooHigh: _quantityTooHigh,
-    return true;
+      isDuplicateBoxNo: _isDuplicateBoxNo,
+    );
   }
 
   void _submitFromKeyboard() {
@@ -710,36 +584,16 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
   }
 
   int? get _currentManyToOneBoxNo {
-    final boxNo = int.tryParse(_boxNoController.text.trim());
+    return boxing_calculations.currentManyToOneBoxNo(_boxNoController.text);
-    if (boxNo == null || boxNo <= 0) return null;
-    return boxNo;
   }
 
   List<ManyToOnePackedItem> get _visibleManyToOnePackedItems {
-    final boxNo = _currentManyToOneBoxNo;
+    return boxing_calculations.visibleManyToOnePackedItems(
-    if (boxNo == null) return const [];
+      boxNo: _currentManyToOneBoxNo,
-    final byItemId = <int, ManyToOnePackedItem>{};
+      existingBoxes: _existingBoxes,
-    for (final box in _existingBoxes.where((box) => box.boxNo == boxNo)) {
+      packedItems: _manyToOnePackedItems,
-      for (final item in box.items) {
+      paichanNo: _paichanNo,
-        final boxItemId = item.boxItemId;
+    );
-        if (boxItemId == null) continue;
-        byItemId[boxItemId] = ManyToOnePackedItem(
-          boxItemId: boxItemId,
-          zongpaiNo: item.zongpaiNo,
-          paichanNo: _paichanNo,
-          workOrderNo: item.workOrderNo,
-          boxNo: boxNo,
-          quantity: item.quantity,
-          totalQuantity: item.totalQuantity,
-        );
-      }
-    }
-    for (final item in _manyToOnePackedItems.where(
-      (item) => item.boxNo == boxNo,
-    )) {
-      byItemId[item.boxItemId] = item;
-    }
-    return byItemId.values.toList(growable: false);
   }
 
   Future<bool> _submit() async {
@@ -839,7 +693,7 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
           );
         } else {
           setState(() {
-            _phase = _Phase.scanned;
+            _phase = BoxingPhase.scanned;
             _boxNoController.text = (_maxBoxNo + 1).toString();
             _quantityController.text = remaining.toString();
             _quantityController.selection = TextSelection(
@@ -872,7 +726,7 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
               ),
             );
           }
-          _phase = _Phase.waiting;
+          _phase = BoxingPhase.waiting;
           _zongpaiNo = null;
           _editingPackedItemId = null;
           _editingPackedQuantity = '';
@@ -925,62 +779,31 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
     int boxNo,
     int quantity,
   ) {
-    final nextBoxes = <BoxDetailData>[];
+    final result = box_mutations.replaceExistingBoxItem(
-    for (final box in _existingBoxes) {
+      existingBoxes: _existingBoxes,
-      final items = box.items.where((item) {
+      editing: editing,
-        return item.boxItemId != editing.boxItemId;
+      boxNo: boxNo,
-      }).toList();
+      quantity: quantity,
-      if (items.isNotEmpty) {
-        nextBoxes.add(BoxDetailData(boxNo: box.boxNo, items: items));
-      }
-    }
-
-    final targetIndex = nextBoxes.indexWhere((box) => box.boxNo == boxNo);
-    final updatedItem = BoxItemData(
-      boxItemId: editing.boxItemId,
       zongpaiNo: _zongpaiNo!,
       workOrderNo: _workOrderNo,
-      quantity: quantity,
       totalQuantity: _erpQuantity,
     );
-    if (targetIndex >= 0) {
+    _existingBoxes = result.boxes;
-      final target = nextBoxes[targetIndex];
+    _maxBoxNo = result.maxBoxNo;
-      nextBoxes[targetIndex] = BoxDetailData(
-        boxNo: target.boxNo,
-        items: [...target.items, updatedItem],
-      );
-    } else {
-      nextBoxes.add(BoxDetailData(boxNo: boxNo, items: [updatedItem]));
-    }
-    nextBoxes.sort((a, b) => a.boxNo.compareTo(b.boxNo));
-    _existingBoxes = nextBoxes;
-    _maxBoxNo = nextBoxes.fold<int>(
-      0,
-      (max, box) => box.boxNo > max ? box.boxNo : max,
-    );
   }
 
   void _addExistingBoxItem(int boxNo, int quantity, int? boxItemId) {
-    final item = BoxItemData(
+    final result = box_mutations.addExistingBoxItem(
+      existingBoxes: _existingBoxes,
+      boxNo: boxNo,
+      quantity: quantity,
       boxItemId: boxItemId,
       zongpaiNo: _zongpaiNo!,
       workOrderNo: _workOrderNo,
-      quantity: quantity,
       totalQuantity: _erpQuantity,
     );
-    final index = _existingBoxes.indexWhere((box) => box.boxNo == boxNo);
+    _existingBoxes = result.boxes;
-    if (index < 0) {
+    _maxBoxNo = result.maxBoxNo;
-      _existingBoxes = [
-        ..._existingBoxes,
-        BoxDetailData(boxNo: boxNo, items: [item]),
-      ]..sort((a, b) => a.boxNo.compareTo(b.boxNo));
-      return;
-    }
-
-    final next = List<BoxDetailData>.from(_existingBoxes);
-    final box = next[index];
-    next[index] = BoxDetailData(boxNo: box.boxNo, items: [...box.items, item]);
-    _existingBoxes = next;
   }
 
   void _finishManyToOneBox() {
@@ -990,7 +813,7 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
       _editingPackedQuantity = '';
       _deletingPackedItemId = null;
       _zongpaiNo = null;
-      _phase = _Phase.waiting;
+      _phase = BoxingPhase.waiting;
       _quantityController.clear();
       _boxNoController.text = (_maxBoxNo + 1).toString();
       _statusOverrideText = null;
@@ -1016,9 +839,11 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
   }
 
   int _maxAssignedQuantity(CurrentZongpaiBoxData item) {
-    final total = _erpQuantity ?? 0;
+    return boxing_calculations.maxAssignedQuantity(
-    final packedWithoutItem = _packedQuantity - item.quantity;
+      totalQuantity: _erpQuantity,
-    return total - packedWithoutItem;
+      packedQuantity: _packedQuantity,
+      itemQuantity: item.quantity,
+    );
   }
 
   void _refreshSingleCodeNewInput({bool focusQuantity = true}) {
@@ -1246,39 +1071,14 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
     int boxNo,
     int quantity,
   ) {
-    final nextBoxes = <BoxDetailData>[];
+    final result = box_mutations.replaceExistingPackedItem(
-    for (final box in _existingBoxes) {
+      existingBoxes: _existingBoxes,
-      final items = box.items.where((boxItem) {
+      item: item,
-        return boxItem.boxItemId != item.boxItemId;
+      boxNo: boxNo,
-      }).toList();
-      if (items.isNotEmpty) {
-        nextBoxes.add(BoxDetailData(boxNo: box.boxNo, items: items));
-      }
-    }
-
-    final updatedItem = BoxItemData(
-      boxItemId: item.boxItemId,
-      zongpaiNo: item.zongpaiNo,
-      workOrderNo: item.workOrderNo,
       quantity: quantity,
-      totalQuantity: item.totalQuantity,
-    );
-    final targetIndex = nextBoxes.indexWhere((box) => box.boxNo == boxNo);
-    if (targetIndex >= 0) {
-      final target = nextBoxes[targetIndex];
-      nextBoxes[targetIndex] = BoxDetailData(
-        boxNo: target.boxNo,
-        items: [...target.items, updatedItem],
-      );
-    } else {
-      nextBoxes.add(BoxDetailData(boxNo: boxNo, items: [updatedItem]));
-    }
-    nextBoxes.sort((a, b) => a.boxNo.compareTo(b.boxNo));
-    _existingBoxes = nextBoxes;
-    _maxBoxNo = nextBoxes.fold<int>(
-      0,
-      (max, box) => box.boxNo > max ? box.boxNo : max,
     );
+    _existingBoxes = result.boxes;
+    _maxBoxNo = result.maxBoxNo;
   }
 
   Future<void> _deletePackedItem(ManyToOnePackedItem item) async {
@@ -1331,20 +1131,12 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
   }
 
   void _removeExistingBoxItem(int boxItemId) {
-    final nextBoxes = <BoxDetailData>[];
+    final result = box_mutations.removeExistingBoxItem(
-    for (final box in _existingBoxes) {
+      existingBoxes: _existingBoxes,
-      final items = box.items
+      boxItemId: boxItemId,
-          .where((item) => item.boxItemId != boxItemId)
-          .toList();
-      if (items.isNotEmpty) {
-        nextBoxes.add(BoxDetailData(boxNo: box.boxNo, items: items));
-      }
-    }
-    _existingBoxes = nextBoxes;
-    _maxBoxNo = nextBoxes.fold<int>(
-      0,
-      (max, box) => box.boxNo > max ? box.boxNo : max,
     );
+    _existingBoxes = result.boxes;
+    _maxBoxNo = result.maxBoxNo;
   }
 
   // === Status bar management ===
@@ -1392,69 +1184,22 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
   // === 状态文字 ===
 
   void _updateBaseStatus() {
-    if (_isAutoProcessing) {
+    final status = boxingStatusFor(
-      _statusDot = StatusDotColor.orange;
+      isAutoProcessing: _isAutoProcessing,
-      _statusText = '正在同步转运数据...';
+      isSubmitting: _isSubmitting,
-      return;
+      isDuplicateBoxNo: _isDuplicateBoxNo,
-    }
+      quantityTooHigh: _quantityTooHigh,
-    if (_isSubmitting) {
+      isEditingAssigned: _editingAssignedItemId != null,
-      _statusDot = StatusDotColor.orange;
+      isDeletingAssigned: _deletingAssignedItemId != null,
-      _statusText = '正在提交…';
+      hasPaichanSwitchNotice: _paichanSwitchNotice != null,
-      return;
+      phase: _phase,
-    }
+      isMultiCode: _mode == BoxingMode.multiCode,
-    if (_isDuplicateBoxNo && _phase == _Phase.scanned) {
+      hasVisibleManyToOneItems: _visibleManyToOnePackedItems.isNotEmpty,
-      _statusDot = StatusDotColor.amber;
+      remainingQuantity: _remainingQuantity,
-      _statusText = '箱号 ${_boxNoController.text} 已存在，请重新输入';
+      boxNoText: _boxNoController.text,
-      return;
+    );
-    }
+    _statusDot = status.dot;
-    if (_quantityTooHigh && _phase == _Phase.scanned) {
+    _statusText = status.text;
-      _statusDot = StatusDotColor.red;
-      _statusText = '超出可装数量上限';
-      return;
-    }
-    if (_editingAssignedItemId != null) {
-      _statusDot = StatusDotColor.amber;
-      _statusText = '正在编辑已分配记录';
-      return;
-    }
-    if (_deletingAssignedItemId != null) {
-      _statusDot = StatusDotColor.red;
-      _statusText = '请确认是否删除该箱记录';
-      return;
-    }
-    if (_paichanSwitchNotice != null) {
-      _statusDot = StatusDotColor.blue;
-      _statusText = '排产号已切换，箱号已重置';
-      return;
-    }
-    switch (_phase) {
-      case _Phase.waiting:
-        _statusDot = StatusDotColor.blue;
-        if (_mode == BoxingMode.multiCode &&
-            _visibleManyToOnePackedItems.isNotEmpty) {
-          _statusText = '请继续扫码或完成本箱';
-        } else {
-          _statusText = '等待扫码';
-        }
-      case _Phase.scanned:
-        _statusDot = StatusDotColor.blue;
-        if (_remainingQuantity <= 0) {
-          _statusDot = StatusDotColor.red;
-          _statusText = '该总排号已全部装箱完毕';
-          return;
-        }
-        _statusText = _mode == BoxingMode.multiCode
-            ? '数量已填入，请确认或修改'
-            : '数量已填入，请确认或修改';
-      case _Phase.submitted:
-        _statusDot = StatusDotColor.green;
-        switch (_mode) {
-          case BoxingMode.singleCode:
-            _statusText = '装箱成功，可继续扫码';
-          case BoxingMode.multiCode:
-            _statusText = '请扫描下一个总排号';
-        }
-    }
   }
 
   // === Build ===
@@ -1487,12 +1232,25 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
         ),
         body: Column(
           children: [
-            ..._buildNoticeBanners(),
+            BoxingNoticeBanners(
+              isAutoProcessing: _isAutoProcessing,
+              autoWarnings: _autoWarnings,
+              paichanSwitchNotice: _paichanSwitchNotice,
+              isDuplicateBoxNo: _isDuplicateBoxNo,
+              quantityTooHigh: _quantityTooHigh,
+              phase: _phase,
+              boxNoText: _boxNoController.text,
+              remainingQuantity: _remainingQuantity,
+              zongpaiNo: _zongpaiNo,
+              completedJumpBoxNo: _completedJumpBoxNo,
+              onJumpToCompletedBox: _jumpToCompletedBox,
+            ),
 
             Expanded(
               child: _mode == BoxingMode.multiCode
                   ? MultiCodeBody(
-                      hasScan: _zongpaiNo != null && _phase == _Phase.scanned,
+                      hasScan:
+                          _zongpaiNo != null && _phase == BoxingPhase.scanned,
                       zongpaiNo: _zongpaiNo,
                       paichanNo: _paichanNo,
                       workOrderNo: _workOrderNo,
@@ -1532,9 +1290,10 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
                           setState(() => _deletingPackedItemId = null),
                     )
                   : SingleCodeBody(
-                      isWaiting: _phase == _Phase.waiting && _zongpaiNo == null,
+                      isWaiting:
+                          _phase == BoxingPhase.waiting && _zongpaiNo == null,
                       isFinished:
-                          _phase == _Phase.scanned &&
+                          _phase == BoxingPhase.scanned &&
                           _zongpaiNo != null &&
                           _remainingQuantity <= 0,
                       zongpaiNo: _zongpaiNo,
@@ -1586,139 +1345,4 @@ class _BoxingPageState extends State<BoxingPage> with WidgetsBindingObserver {
       ),
     );
   }
-
-  List<Widget> _buildNoticeBanners() {
-    final banners = <Widget>[];
-    if (_isAutoProcessing) {
-      banners.add(
-        _noticeBanner(
-          icon: SizedBox(
-            width: 12,
-            height: 12,
-            child: CircularProgressIndicator(
-              strokeWidth: 1.5,
-              color: Colors.orange.shade700,
-            ),
-          ),
-          text: '正在同步转运数据...',
-          background: Colors.orange.shade50,
-          foreground: Colors.orange.shade900,
-          border: Colors.orange.shade100,
-        ),
-      );
-    }
-    if (_autoWarnings.isNotEmpty) {
-      banners.add(
-        _noticeBanner(
-          icon: Icon(
-            Icons.warning_amber,
-            size: 14,
-            color: Colors.amber.shade900,
-          ),
-          text: _autoWarnings.join('；'),
-          background: Colors.amber.shade100,
-          foreground: Colors.amber.shade900,
-          border: Colors.amber.shade200,
-        ),
-      );
-    }
-    if (_paichanSwitchNotice != null) {
-      banners.add(
-        _noticeBanner(
-          icon: Icon(Icons.info_outline, size: 14, color: Colors.blue.shade900),
-          text: _paichanSwitchNotice!,
-          background: Colors.blue.shade50,
-          foreground: Colors.blue.shade900,
-          border: Colors.blue.shade100,
-        ),
-      );
-    }
-    if (_isDuplicateBoxNo && _phase == _Phase.scanned) {
-      banners.add(
-        _noticeBanner(
-          icon: Icon(
-            Icons.warning_amber,
-            size: 14,
-            color: Colors.amber.shade900,
-          ),
-          text: '箱号 ${_boxNoController.text} 已存在，请重新输入',
-          background: Colors.amber.shade100,
-          foreground: Colors.amber.shade900,
-          border: Colors.amber.shade200,
-        ),
-      );
-    }
-    if (_quantityTooHigh && _phase == _Phase.scanned) {
-      banners.add(
-        _noticeBanner(
-          icon: Icon(Icons.close, size: 14, color: Colors.red.shade800),
-          text: '超出可装数量上限（最多可装 $_remainingQuantity 件）',
-          background: Colors.red.shade50,
-          foreground: Colors.red.shade800,
-          border: Colors.red.shade100,
-        ),
-      );
-    }
-    if (_phase == _Phase.scanned &&
-        _zongpaiNo != null &&
-        _remainingQuantity <= 0) {
-      final jumpBoxNo = _completedJumpBoxNo;
-      if (jumpBoxNo != null) {
-        banners.add(
-          GestureDetector(
-            onTap: _jumpToCompletedBox,
-            behavior: HitTestBehavior.opaque,
-            child: _noticeBanner(
-              icon: Icon(Icons.warning, size: 14, color: Colors.amber.shade800),
-              text: '${_zongpaiNo!} 已完成装箱。(P4跳转所在箱号)',
-              background: Colors.amber.shade50,
-              foreground: Colors.amber.shade800,
-              border: Colors.amber.shade200,
-            ),
-          ),
-        );
-      } else {
-        banners.add(
-          _noticeBanner(
-            icon: Icon(Icons.warning, size: 14, color: Colors.red.shade800),
-            text: '${_zongpaiNo!} 已全部装箱完毕，无需操作',
-            background: Colors.red.shade50,
-            foreground: Colors.red.shade800,
-            border: Colors.red.shade100,
-          ),
-        );
-      }
-    }
-    return banners;
-  }
-
-  Widget _noticeBanner({
-    required Widget icon,
-    required String text,
-    required Color background,
-    required Color foreground,
-    required Color border,
-  }) {
-    return Container(
-      width: double.infinity,
-      padding: const EdgeInsets.symmetric(vertical: 6, horizontal: 12),
-      decoration: BoxDecoration(
-        color: background,
-        border: Border(bottom: BorderSide(color: border)),
-      ),
-      child: Row(
-        children: [
-          icon,
-          const SizedBox(width: 6),
-          Expanded(
-            child: Text(
-              text,
-              style: TextStyle(fontSize: 12, color: foreground),
-              overflow: TextOverflow.ellipsis,
-            ),
-          ),
-        ],
-      ),
-    );
-  }
 }

test/pages/boxing/boxing_box_mutations_test.dart

@@ -0,0 +1,88 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pad_scanner/pages/boxing/boxing_box_mutations.dart';
+import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+import 'package:pad_scanner/services/api_service.dart';
+
+void main() {
+  group('boxing box mutations', () {
+    test('adds item to a new sorted box', () {
+      final result = addExistingBoxItem(
+        existingBoxes: [BoxDetailData(boxNo: 3, items: const [])],
+        boxNo: 2,
+        quantity: 5,
+        boxItemId: 22,
+        zongpaiNo: 'ZP022',
+        workOrderNo: 'WO022',
+        totalQuantity: 5,
+      );
+
+      expect(result.boxes.map((box) => box.boxNo), [2, 3]);
+      expect(result.maxBoxNo, 3);
+      expect(result.boxes.first.items.single.zongpaiNo, 'ZP022');
+    });
+
+    test('replaces single code item and removes empty source box', () {
+      final result = replaceExistingBoxItem(
+        existingBoxes: [
+          BoxDetailData(
+            boxNo: 1,
+            items: [BoxItemData(boxItemId: 1, zongpaiNo: 'ZP001', quantity: 2)],
+          ),
+        ],
+        editing: CurrentZongpaiBoxData(boxItemId: 1, boxNo: 1, quantity: 2),
+        boxNo: 4,
+        quantity: 3,
+        zongpaiNo: 'ZP001',
+        workOrderNo: 'WO001',
+        totalQuantity: 5,
+      );
+
+      expect(result.boxes.map((box) => box.boxNo), [4]);
+      expect(result.boxes.single.items.single.quantity, 3);
+      expect(result.maxBoxNo, 4);
+    });
+
+    test('moves packed item to a different box', () {
+      final result = replaceExistingPackedItem(
+        existingBoxes: [
+          BoxDetailData(
+            boxNo: 2,
+            items: [BoxItemData(boxItemId: 9, zongpaiNo: 'ZP009', quantity: 1)],
+          ),
+        ],
+        item: const ManyToOnePackedItem(
+          boxItemId: 9,
+          zongpaiNo: 'ZP009',
+          workOrderNo: 'WO009',
+          boxNo: 2,
+          quantity: 1,
+          totalQuantity: 3,
+        ),
+        boxNo: 5,
+        quantity: 2,
+      );
+
+      expect(result.boxes.map((box) => box.boxNo), [5]);
+      expect(result.boxes.single.items.single.quantity, 2);
+    });
+
+    test('removes item and drops empty box', () {
+      final result = removeExistingBoxItem(
+        existingBoxes: [
+          BoxDetailData(
+            boxNo: 1,
+            items: [BoxItemData(boxItemId: 1, zongpaiNo: 'ZP001', quantity: 2)],
+          ),
+          BoxDetailData(
+            boxNo: 3,
+            items: [BoxItemData(boxItemId: 2, zongpaiNo: 'ZP002', quantity: 1)],
+          ),
+        ],
+        boxItemId: 1,
+      );
+
+      expect(result.boxes.map((box) => box.boxNo), [3]);
+      expect(result.maxBoxNo, 3);
+    });
+  });
+}

test/pages/boxing/boxing_calculations_test.dart

@@ -0,0 +1,123 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pad_scanner/pages/boxing/boxing_calculations.dart';
+import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+import 'package:pad_scanner/services/api_service.dart';
+
+void main() {
+  group('boxing calculations', () {
+    final currentBoxes = [
+      CurrentZongpaiBoxData(boxItemId: 1, boxNo: 1, quantity: 4),
+      CurrentZongpaiBoxData(boxItemId: 2, boxNo: 2, quantity: 3),
+    ];
+
+    test('calculates packed and remaining quantity', () {
+      expect(packedQuantity(currentBoxes), 7);
+      expect(
+        remainingQuantity(totalQuantity: 10, currentBoxes: currentBoxes),
+        3,
+      );
+    });
+
+    test('detects quantity too high only when remaining is positive', () {
+      expect(quantityTooHigh(remainingQuantity: 3, quantityText: '4'), isTrue);
+      expect(quantityTooHigh(remainingQuantity: 3, quantityText: '3'), isFalse);
+      expect(quantityTooHigh(remainingQuantity: 0, quantityText: '1'), isFalse);
+    });
+
+    test('validates submit conditions', () {
+      expect(
+        canSubmitBoxing(
+          isSubmitting: false,
+          phase: BoxingPhase.scanned,
+          zongpaiNo: 'ZP001',
+          boxNoText: '1',
+          quantityText: '2',
+          remainingQuantity: 3,
+          quantityTooHigh: false,
+          isDuplicateBoxNo: false,
+        ),
+        isTrue,
+      );
+
+      expect(
+        canSubmitBoxing(
+          isSubmitting: true,
+          phase: BoxingPhase.scanned,
+          zongpaiNo: 'ZP001',
+          boxNoText: '1',
+          quantityText: '2',
+          remainingQuantity: 3,
+          quantityTooHigh: false,
+          isDuplicateBoxNo: false,
+        ),
+        isFalse,
+      );
+    });
+
+    test('detects duplicate box number in single code mode', () {
+      expect(
+        singleCodeBoxNoIsDuplicate(
+          boxNoText: '1',
+          currentBoxes: currentBoxes,
+          editingBoxItemId: null,
+        ),
+        isTrue,
+      );
+      expect(
+        singleCodeBoxNoIsDuplicate(
+          boxNoText: '1',
+          currentBoxes: currentBoxes,
+          editingBoxItemId: 1,
+        ),
+        isFalse,
+      );
+    });
+
+    test('merges visible many-to-one items by box item id', () {
+      final existingBoxes = [
+        BoxDetailData(
+          boxNo: 8,
+          items: [
+            BoxItemData(
+              boxItemId: 11,
+              zongpaiNo: 'ZP011',
+              workOrderNo: 'WO011',
+              quantity: 2,
+              totalQuantity: 6,
+            ),
+          ],
+        ),
+      ];
+      final packedItems = [
+        const ManyToOnePackedItem(
+          boxItemId: 11,
+          zongpaiNo: 'ZP011',
+          paichanNo: 'PC001',
+          workOrderNo: 'WO011',
+          boxNo: 8,
+          quantity: 3,
+          totalQuantity: 6,
+        ),
+        const ManyToOnePackedItem(
+          boxItemId: 12,
+          zongpaiNo: 'ZP012',
+          paichanNo: 'PC001',
+          workOrderNo: 'WO012',
+          boxNo: 8,
+          quantity: 1,
+          totalQuantity: 4,
+        ),
+      ];
+
+      final visible = visibleManyToOnePackedItems(
+        boxNo: 8,
+        existingBoxes: existingBoxes,
+        packedItems: packedItems,
+        paichanNo: 'PC001',
+      );
+
+      expect(visible.map((item) => item.boxItemId), [11, 12]);
+      expect(visible.first.quantity, 3);
+    });
+  });
+}

test/pages/boxing/boxing_status_presenter_test.dart

@@ -0,0 +1,81 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pad_scanner/pages/boxing/boxing_models.dart';
+import 'package:pad_scanner/pages/boxing/boxing_status_presenter.dart';
+import 'package:pad_scanner/widgets/status_bar.dart';
+
+void main() {
+  BoxingStatusPresentation status({
+    bool isAutoProcessing = false,
+    bool isSubmitting = false,
+    bool isDuplicateBoxNo = false,
+    bool quantityTooHigh = false,
+    bool isEditingAssigned = false,
+    bool isDeletingAssigned = false,
+    bool hasPaichanSwitchNotice = false,
+    BoxingPhase phase = BoxingPhase.waiting,
+    bool isMultiCode = false,
+    bool hasVisibleManyToOneItems = false,
+    int remainingQuantity = 1,
+    String boxNoText = '1',
+  }) {
+    return boxingStatusFor(
+      isAutoProcessing: isAutoProcessing,
+      isSubmitting: isSubmitting,
+      isDuplicateBoxNo: isDuplicateBoxNo,
+      quantityTooHigh: quantityTooHigh,
+      isEditingAssigned: isEditingAssigned,
+      isDeletingAssigned: isDeletingAssigned,
+      hasPaichanSwitchNotice: hasPaichanSwitchNotice,
+      phase: phase,
+      isMultiCode: isMultiCode,
+      hasVisibleManyToOneItems: hasVisibleManyToOneItems,
+      remainingQuantity: remainingQuantity,
+      boxNoText: boxNoText,
+    );
+  }
+
+  group('boxingStatusFor', () {
+    test('reports waiting and multi-code continuation states', () {
+      expect(status().text, '等待扫码');
+      final multi = status(isMultiCode: true, hasVisibleManyToOneItems: true);
+      expect(multi.text, '请继续扫码或完成本箱');
+    });
+
+    test('prioritizes transient and validation states', () {
+      expect(status(isSubmitting: true).text, '正在提交…');
+      expect(
+        status(isDuplicateBoxNo: true, phase: BoxingPhase.scanned).dot,
+        StatusDotColor.amber,
+      );
+      expect(
+        status(quantityTooHigh: true, phase: BoxingPhase.scanned).text,
+        '超出可装数量上限',
+      );
+    });
+
+    test('reports edit delete and switched paichan states', () {
+      expect(status(isEditingAssigned: true).text, '正在编辑已分配记录');
+      expect(status(isDeletingAssigned: true).dot, StatusDotColor.red);
+      expect(status(hasPaichanSwitchNotice: true).text, '排产号已切换，箱号已重置');
+    });
+
+    test('reports scanned completed and submitted states', () {
+      expect(
+        status(phase: BoxingPhase.scanned, remainingQuantity: 0).text,
+        '该总排号已全部装箱完毕',
+      );
+      expect(
+        status(phase: BoxingPhase.scanned, remainingQuantity: 2).text,
+        '数量已填入，请确认或修改',
+      );
+      expect(
+        status(phase: BoxingPhase.submitted, isMultiCode: false).text,
+        '装箱成功，可继续扫码',
+      );
+      expect(
+        status(phase: BoxingPhase.submitted, isMultiCode: true).text,
+        '请扫描下一个总排号',
+      );
+    });
+  });
+}