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,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}