import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:tdesign_flutter/tdesign_flutter.dart';
import '../../core/theme/app_colors.dart';
import '../../core/i18n/app_localizations.dart';
import '../../shared/widgets/action_bar.dart';
import '../../shared/widgets/form_section.dart';
import '../../shared/widgets/form_field_row.dart';
import '../shell/nav_bar_config.dart';

class ExpenseApplicationApplyPage extends ConsumerStatefulWidget {
  final String? id;
  const ExpenseApplicationApplyPage({super.key, this.id});

  @override
  ConsumerState<ExpenseApplicationApplyPage> createState() =>
      _ExpenseApplicationApplyPageState();
}

class _ExpenseApplicationApplyPageState
    extends ConsumerState<ExpenseApplicationApplyPage> {
  // ── 基本信息 ──
  int _urgency = 0; // 0=普通, 1=紧急, 2=特急
  static const _urgencyLabels = ['普通', '紧急', '特急'];
  final Set<String> _expenseTypes = {};
  static const _expenseTypeOptions = [
    ('travel', '差旅费'),
    ('entertainment', '业务招待费'),
    ('procurement', '日常采购'),
    ('activity', '活动经费'),
    ('office', '办公费'),
    ('meeting', '会议费'),
    ('training', '培训费'),
  ];

  bool _isTaxIncluded = false;
  final _purposeController = TextEditingController();

  // ── 关联管控 ──
  String? _selectedProjectName;
  int? _selectedProjectId;
  String? _selectedSubjectName;
  int? _selectedSubjectId;
  final _availableBudget = 50000.00;
  final _referenceNoController = TextEditingController();

  // ── 费用明细 ──
  final List<_DetailItem> _details = [];
  int _detailIdCounter = 1;

  // ── 附件 ──
  final List<String> _attachments = []; // mock file names

  // ── 专用字段 ──
  String _estimatedStartDate = '';
  String _estimatedEndDate = '';
  String _entertainmentTarget = '';
  String _venue = '';

  @override
  void dispose() {
    _purposeController.dispose();
    _referenceNoController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);

    ref.read(navBarConfigProvider.notifier).update(
          NavBarConfig(
            title: l10n.get('expenseApplyRequest'),
            showBack: true,
            onBack: () {
              if (_hasUnsaved()) {
                _showConfirmDialog('确认退出', '当前内容尚未保存，是否退出？', '继续编辑', '放弃并退出', () => context.pop());
              } else {
                context.pop();
              }
            },
          ),
        );

    return PopScope(
      canPop: false,
      onPopInvokedWithResult: (didPop, _) {
        if (!didPop) {
          if (_hasUnsaved()) {
            _showConfirmDialog('确认退出', '当前内容尚未保存，是否退出？', '继续编辑', '放弃并退出', () => context.pop());
          } else {
            context.pop();
          }
        }
      },
      child: Column(
        children: [
          Expanded(
            child: SingleChildScrollView(
              padding: const EdgeInsets.all(16),
              child: Column(
                children: [
                  _buildBasicInfo(l10n),
                  const SizedBox(height: 16),
                  _buildTypeSpecificFields(l10n),
                  const SizedBox(height: 16),
                  _buildControlSection(l10n),
                  const SizedBox(height: 16),
                  _buildDetailsSection(l10n),
                  const SizedBox(height: 16),
                  _buildAttachmentSection(l10n),
                  const SizedBox(height: 80),
                ],
              ),
            ),
          ),
          _buildBottomBar(l10n),
        ],
      ),
    );
  }

  // ═══ 1. 基本信息 ═══
  Widget _buildBasicInfo(AppLocalizations l10n) {
    return FormSection(
      title: l10n.get('basicInfo'),
      children: [
        FormFieldRow(label: l10n.get('applicant'), value: '张三', readOnly: true, showArrow: false),
        FormFieldRow(label: l10n.get('department'), value: '技术部', readOnly: true, showArrow: false),
        FormFieldRow(label: l10n.get('date'), value: _today(), readOnly: true, showArrow: false),
        const SizedBox(height: 12),
        _label(l10n.get('emergencyLevel')),
        const SizedBox(height: 6),
        _buildUrgencyRadio(),
        const SizedBox(height: 12),
        _label(l10n.get('expenseType')),
        const SizedBox(height: 6),
        Wrap(
          spacing: 8, runSpacing: 8,
          children: _expenseTypeOptions.map((opt) {
            final sel = _expenseTypes.contains(opt.$1);
            return GestureDetector(
              onTap: () => setState(() => sel ? _expenseTypes.remove(opt.$1) : _expenseTypes.add(opt.$1)),
              child: TDTag(opt.$2, size: TDTagSize.medium, theme: sel ? TDTagTheme.primary : TDTagTheme.defaultTheme, isOutline: !sel),
            );
          }).toList(),
        ),
        const SizedBox(height: 12),
        Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
          _label(l10n.get('isTaxIncluded')),
          TDSwitch(isOn: _isTaxIncluded, onChanged: (v) { setState(() => _isTaxIncluded = v); return true; }),
        ]),
        const SizedBox(height: 12),
        _label(l10n.get('feeReason')),
        const SizedBox(height: 4),
        TDTextarea(
          controller: _purposeController,
          hintText: l10n.get('enterFeeReason'),
          maxLength: 200,
          backgroundColor: AppColors.bgPage,
        ),
        const SizedBox(height: 12),
        FormFieldRow(label: l10n.get('validUntil'), hint: l10n.get('pleaseSelect'), onTap: () => _pickDate((d) {})),
      ],
    );
  }

  Widget _buildUrgencyRadio() {
    return Row(
      children: List.generate(3, (i) {
        final sel = _urgency == i;
        return Padding(
          padding: EdgeInsets.only(right: i < 2 ? 24 : 0),
          child: GestureDetector(
            onTap: () => setState(() => _urgency = i),
            child: Row(mainAxisSize: MainAxisSize.min, children: [
              Container(
                width: 18, height: 18,
                decoration: BoxDecoration(shape: BoxShape.circle, border: Border.all(color: sel ? AppColors.primary : AppColors.textPlaceholder, width: 2)),
                child: sel ? Center(child: Container(width: 8, height: 8, decoration: const BoxDecoration(shape: BoxShape.circle, color: AppColors.primary))) : null,
              ),
              const SizedBox(width: 6),
              Text(_urgencyLabels[i], style: TextStyle(fontSize: AppFontSizes.body, color: sel ? AppColors.primary : AppColors.textSecondary)),
            ]),
          ),
        );
      }),
    );
  }

  // ═══ 2. 类型专用字段 ═══
  Widget _buildTypeSpecificFields(AppLocalizations l10n) {
    final ws = <Widget>[];
    if (_expenseTypes.contains('travel')) ws.add(_buildTravelFields(l10n));
    if (_expenseTypes.contains('entertainment')) { ws.add(const SizedBox(height: 16)); ws.add(_buildEntertainmentFields(l10n)); }
    if (_expenseTypes.contains('meeting')) { ws.add(const SizedBox(height: 16)); ws.add(_buildMeetingFields(l10n)); }
    return ws.isEmpty ? const SizedBox.shrink() : Column(children: ws);
  }

  Widget _buildTravelFields(AppLocalizations l10n) {
    return FormSection(title: '差旅费专用', children: [
      FormFieldRow(label: l10n.get('estimatedStartDate'), value: _estimatedStartDate, hint: l10n.get('pleaseSelect'), onTap: () => _pickDate((d) => setState(() => _estimatedStartDate = d))),
      FormFieldRow(label: l10n.get('estimatedEndDate'), value: _estimatedEndDate, hint: l10n.get('pleaseSelect'), onTap: () => _pickDate((d) => setState(() => _estimatedEndDate = d))),
      const SizedBox(height: 8),
      Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [_label(l10n.get('isOvernight')), TDSwitch(onChanged: (_) => true)]),
      const SizedBox(height: 8),
      FormFieldRow(label: l10n.get('transportType'), value: '高铁/动车', onTap: () => _showListPicker('选择交通工具', ['飞机', '高铁/动车', '火车（普速）', '自驾'], (_) {})),
    ]);
  }

  Widget _buildEntertainmentFields(AppLocalizations l10n) {
    return FormSection(title: '招待费专用', children: [
      FormFieldRow(label: '招待对象单位', value: _entertainmentTarget, hint: '请输入', onTap: () => _showTextInput('招待对象单位', (v) => setState(() => _entertainmentTarget = v))),
      FormFieldRow(label: '招待层级', value: '普通', onTap: () => _showListPicker('选择招待层级', ['普通', '重要', 'VIP'], (_) {})),
      FormFieldRow(label: '外部人数', value: '3', onTap: () => _showNumberInput('外部人数', (_) {})),
      FormFieldRow(label: '内部陪同人数', value: '2', onTap: () => _showNumberInput('内部陪同人数', (_) {})),
      FormFieldRow(label: l10n.get('venue'), value: _venue, hint: '请输入地点', onTap: () => _showTextInput(l10n.get('venue'), (v) => setState(() => _venue = v))),
    ]);
  }

  Widget _buildMeetingFields(AppLocalizations l10n) {
    return FormSection(title: '会议费专用', children: [
      FormFieldRow(label: l10n.get('estimatedStartDate'), hint: l10n.get('pleaseSelect'), onTap: () => _pickDate((_) {})),
      FormFieldRow(label: l10n.get('estimatedEndDate'), hint: l10n.get('pleaseSelect'), onTap: () => _pickDate((_) {})),
      FormFieldRow(label: l10n.get('venue'), value: _venue, hint: '请输入会议地点', onTap: () => _showTextInput('会议地点', (_) {})),
    ]);
  }

  // ═══ 3. 关联管控 ═══
  static const _mockProjects = [('华东市场拓展', 100), ('ERP系统升级', 101), ('新产品研发', 102), ('华南渠道建设', 103)];
  static const _mockSubjects = [('差旅费', 5), ('招待费', 6), ('办公费', 7), ('培训费', 8)];

  Widget _buildControlSection(AppLocalizations l10n) {
    return FormSection(title: l10n.get('relatedControl'), children: [
      FormFieldRow(label: l10n.get('relatedProject'), value: _selectedProjectName, hint: l10n.get('selectProject'), onTap: () {
        _showListPicker('选择关联项目', _mockProjects.map((p) => p.$1).toList(), (v) {
          final p = _mockProjects.firstWhere((x) => x.$1 == v);
          setState(() { _selectedProjectId = p.$2; _selectedProjectName = p.$1; _selectedSubjectName = null; _selectedSubjectId = null; });
        });
      }),
      FormFieldRow(
        label: l10n.get('budgetSubject'),
        value: _selectedSubjectName,
        hint: l10n.get('selectSubject'),
        onTap: _selectedProjectId != null
            ? () {
                _showListPicker('选择预算科目', _mockSubjects.map((s) => s.$1).toList(), (v) {
                  final s = _mockSubjects.firstWhere((x) => x.$1 == v);
                  setState(() { _selectedSubjectId = s.$2; _selectedSubjectName = s.$1; });
                });
              }
            : null,
      ),
      _buildBudgetRow(l10n),
      const SizedBox(height: 8),
      FormFieldRow(label: '关联合同号', value: _referenceNoController.text, hint: '选填', onTap: () => _showTextInput('关联合同号', (v) => setState(() { _referenceNoController.text = v; _referenceNoController.selection = TextSelection.fromPosition(TextPosition(offset: v.length)); }))),
    ]);
  }

  Widget _buildBudgetRow(AppLocalizations l10n) {
    final over = _totalAmount() > _availableBudget;
    return SizedBox(
      height: 44,
      child: Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
        Text(l10n.get('availableBudget'), style: const TextStyle(fontSize: AppFontSizes.body, color: AppColors.textSecondary)),
        Text('¥${_availableBudget.toStringAsFixed(2)}', style: TextStyle(fontSize: AppFontSizes.subtitle, fontWeight: FontWeight.w700, color: over ? AppColors.danger : AppColors.amountPrimary)),
      ]),
    );
  }

  // ═══ 4. 费用明细 ═══
  Widget _buildDetailsSection(AppLocalizations l10n) {
    return FormSection(title: l10n.get('expenseDetails'), showAction: true, actionText: l10n.get('add'), onActionTap: _showDetailDialog, children: [
      if (_details.isEmpty)
        Padding(padding: const EdgeInsets.symmetric(vertical: 8), child: Text(l10n.get('noDetailHint'), style: const TextStyle(fontSize: AppFontSizes.body, color: AppColors.textPlaceholder)))
      else
        ..._details.asMap().entries.map((e) {
          final d = e.value;
          return Container(
            padding: const EdgeInsets.symmetric(vertical: 6),
            decoration: BoxDecoration(border: e.key < _details.length - 1 ? const Border(bottom: BorderSide(color: AppColors.border)) : null),
            child: Row(children: [
              Expanded(flex: 3, child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
                Text(d.categoryName, style: const TextStyle(fontSize: AppFontSizes.body, color: AppColors.textPrimary)),
                if (d.remark.isNotEmpty) Text(d.remark, style: const TextStyle(fontSize: AppFontSizes.caption, color: AppColors.textPlaceholder)),
              ])),
              Text('${d.quantity}×¥${d.unitPrice.toStringAsFixed(2)}', style: const TextStyle(fontSize: AppFontSizes.caption, color: AppColors.textSecondary)),
              const SizedBox(width: 8),
              Text('¥${d.amount.toStringAsFixed(2)}', style: const TextStyle(fontSize: AppFontSizes.body, fontWeight: FontWeight.w600, color: AppColors.amountPrimary)),
              GestureDetector(onTap: () => setState(() => _details.removeAt(e.key)), child: const Icon(Icons.close, size: 16, color: AppColors.textPlaceholder)),
            ]),
          );
        }),
      Container(height: 1, color: AppColors.border),
      Container(height: 36, padding: const EdgeInsets.symmetric(vertical: 8), child: Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
        Text(l10n.get('total'), style: const TextStyle(fontSize: AppFontSizes.body, fontWeight: FontWeight.w600, color: AppColors.textPrimary)),
        Text('¥${_totalAmount().toStringAsFixed(2)}', style: const TextStyle(fontSize: AppFontSizes.subtitle, fontWeight: FontWeight.w700, color: AppColors.amountPrimary)),
      ])),
      if (_totalAmount() > _availableBudget)
        Padding(padding: const EdgeInsets.only(top: 8), child: Row(children: [
          const Icon(Icons.warning_amber, size: 14, color: AppColors.danger), const SizedBox(width: 6),
          Expanded(child: Text('您的申请金额已超支，提交后将自动触发高管特批流程', style: const TextStyle(fontSize: AppFontSizes.caption, color: AppColors.danger))),
        ])),
    ]);
  }

  double _totalAmount() => _details.fold(0, (s, d) => s + d.amount);

  static const _detailCategories = [('transport', '交通费'), ('hotel', '住宿费'), ('office_supplies', '办公用品'), ('meals', '餐饮费'), ('materials', '材料费'), ('service', '服务费'), ('other', '其他')];
  static const _units = ['张', '间', '人', '天', '套', '个'];

  void _showDetailDialog() {
    String cat = 'transport';
    String unit = '张';
    final qtyCtrl = TextEditingController(text: '1');
    final priceCtrl = TextEditingController();
    final remarkCtrl = TextEditingController();

    showDialog(
      context: context,
      builder: (ctx) => StatefulBuilder(
        builder: (ctx, setDlg) => TDAlertDialog(
          title: '添加费用明细',
          contentWidget: Column(mainAxisSize: MainAxisSize.min, crossAxisAlignment: CrossAxisAlignment.start, children: [
            _label('费用类别'),
            const SizedBox(height: 4),
            GestureDetector(
              onTap: () {
                Navigator.pop(ctx);
                _showListPicker('选择费用类别', _detailCategories.map((c) => c.$2).toList(), (v) {
                  cat = _detailCategories.firstWhere((c) => c.$2 == v).$1;
                  _showDetailDialog();
                });
              },
              child: Container(
                height: 44, padding: const EdgeInsets.symmetric(horizontal: 12),
                decoration: BoxDecoration(color: AppColors.bgPage, borderRadius: BorderRadius.circular(4)),
                child: Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
                  Text(_detailCategories.firstWhere((c) => c.$1 == cat).$2, style: const TextStyle(fontSize: AppFontSizes.body)),
                  const Icon(Icons.arrow_drop_down, color: AppColors.textPlaceholder),
                ]),
              ),
            ),
            const SizedBox(height: 12),
            Row(children: [
              Expanded(child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
                _label('数量'), const SizedBox(height: 4),
                TDInput(controller: qtyCtrl, hintText: '>0'),
              ])),
              const SizedBox(width: 12),
              Expanded(child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
                _label('单位'), const SizedBox(height: 4),
                GestureDetector(
                  onTap: () {
                    Navigator.pop(ctx);
                    _showListPicker('选择单位', _units, (v) { unit = v; _showDetailDialog(); });
                  },
                  child: Container(
                    height: 44, padding: const EdgeInsets.symmetric(horizontal: 12),
                    decoration: BoxDecoration(color: AppColors.bgPage, borderRadius: BorderRadius.circular(4)),
                    child: Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
                      Text(unit, style: const TextStyle(fontSize: AppFontSizes.body)),
                      const Icon(Icons.arrow_drop_down, color: AppColors.textPlaceholder),
                    ]),
                  ),
                ),
              ])),
            ]),
            const SizedBox(height: 12),
            _label('单价'), const SizedBox(height: 4),
            TDInput(controller: priceCtrl, hintText: '>0'),
            const SizedBox(height: 12),
            _label('明细说明'), const SizedBox(height: 4),
            TDInput(controller: remarkCtrl, hintText: '选填'),
          ]),
          leftBtn: TDDialogButtonOptions(title: '取消', action: () => Navigator.pop(ctx)),
          rightBtn: TDDialogButtonOptions(title: '确定', titleColor: AppColors.primary, action: () {
            final q = int.tryParse(qtyCtrl.text) ?? 0;
            final p = double.tryParse(priceCtrl.text) ?? 0;
            if (q <= 0 || p <= 0) { TDToast.showText('数量和单价必须大于0', context: context); return; }
            setState(() => _details.add(_DetailItem(id: _detailIdCounter++, category: cat, categoryName: _detailCategories.firstWhere((c) => c.$1 == cat).$2, quantity: q, unit: unit, unitPrice: p, amount: q * p, remark: remarkCtrl.text)));
            Navigator.pop(ctx);
          }),
        ),
      ),
    );
  }

  // ═══ 5. 附件上传 ═══
  Widget _buildAttachmentSection(AppLocalizations l10n) {
    return FormSection(title: l10n.get('attachmentUpload'), children: [
      Text(l10n.get('maxAttachment'), style: const TextStyle(fontSize: AppFontSizes.caption, color: AppColors.textPlaceholder)),
      const SizedBox(height: 12),
      Wrap(spacing: 8, runSpacing: 8, children: [
        ..._attachments.asMap().entries.map((e) => Stack(
          clipBehavior: Clip.none,
          children: [
            Container(width: 80, height: 80, decoration: BoxDecoration(color: AppColors.primaryLight, borderRadius: BorderRadius.circular(4)),
              child: const Center(child: Icon(Icons.image, color: AppColors.primary, size: 32)),
            ),
            Positioned(right: -4, top: -4, child: GestureDetector(
              onTap: () => setState(() => _attachments.removeAt(e.key)),
              child: Container(width: 20, height: 20, decoration: const BoxDecoration(color: AppColors.danger, shape: BoxShape.circle),
                child: const Icon(Icons.close, size: 12, color: Colors.white),
              ),
            )),
          ],
        )),
        if (_attachments.length < 9)
          GestureDetector(
            onTap: () {
              // Mock: add attachment
              setState(() => _attachments.add('附件_${DateTime.now().millisecondsSinceEpoch}.jpg'));
              TDToast.showText('已添加附件（mock）', context: context);
            },
            child: Container(width: 80, height: 80, decoration: BoxDecoration(color: AppColors.bgPage, borderRadius: BorderRadius.circular(4), border: Border.all(color: AppColors.border)),
              child: const Center(child: Icon(Icons.add, size: 24, color: AppColors.textPlaceholder)),
            ),
          ),
      ]),
    ]);
  }

  // ═══ 6. 底部操作栏 ═══
  Widget _buildBottomBar(AppLocalizations l10n) {
    final isDraft = widget.id != null;
    return ActionBar(
      leftLabel: isDraft ? l10n.get('reset') : null,
      centerLabel: l10n.get('saveDraft'),
      rightLabel: l10n.get('submitApproval'),
      showLeft: isDraft,
      onLeftTap: isDraft ? () => _showConfirmDialog('确认重置', '将清空所有已填内容，此操作不可撤销', '取消', '确认重置', _resetAll) : null,
      onCenterTap: () {
        TDToast.showSuccess('已保存为草稿', context: context);
        context.pop();
      },
      onRightTap: () {
        final err = _validate();
        if (err.isNotEmpty) { TDToast.showText(err.first, context: context); return; }
        TDToast.showSuccess('已提交，等待审批', context: context);
        context.pop();
      },
    );
  }

  List<String> _validate() {
    final e = <String>[];
    if (_expenseTypes.isEmpty) e.add('请至少选择一项费用类型');
    if (_purposeController.text.trim().isEmpty) e.add('请填写费用事由');
    if (_selectedProjectId == null) e.add('请选择关联项目');
    if (_selectedSubjectId == null) e.add('请选择预算科目');
    if (_details.isEmpty) e.add('请至少添加一行费用明细');
    if (_expenseTypes.contains('travel')) {
      if (_estimatedStartDate.isEmpty) e.add('请选择预计开始日期');
      if (_estimatedEndDate.isEmpty) e.add('请选择预计结束日期');
    }
    return e;
  }

  void _resetAll() => setState(() {
    _purposeController.clear(); _expenseTypes.clear(); _urgency = 0; _isTaxIncluded = false;
    _selectedProjectId = null; _selectedProjectName = null; _selectedSubjectId = null; _selectedSubjectName = null;
    _referenceNoController.clear(); _details.clear(); _attachments.clear();
    _estimatedStartDate = ''; _estimatedEndDate = ''; _entertainmentTarget = ''; _venue = '';
  });

  bool _hasUnsaved() => _purposeController.text.isNotEmpty || _expenseTypes.isNotEmpty || _details.isNotEmpty || _attachments.isNotEmpty || _selectedProjectId != null;

  // ═══ 通用弹窗方法 ═══
  void _showConfirmDialog(String title, String content, String leftText, String rightText, VoidCallback onConfirm) {
    showDialog(
      context: context,
      builder: (ctx) => TDAlertDialog(
        title: title,
        content: content,
        leftBtn: TDDialogButtonOptions(title: leftText, titleColor: AppColors.primary, action: () => Navigator.pop(ctx)),
        rightBtn: TDDialogButtonOptions(title: rightText, titleColor: AppColors.danger, action: () { Navigator.pop(ctx); onConfirm(); }),
      ),
    );
  }

  void _showListPicker(String title, List<String> items, Function(String) onPick) {
    showDialog(
      context: context,
      builder: (ctx) => TDAlertDialog(
        title: title,
        contentWidget: SizedBox(width: double.maxFinite, child: ListView(shrinkWrap: true, children: items.map((item) => ListTile(title: Text(item), onTap: () { onPick(item); Navigator.pop(ctx); })).toList())),
        leftBtn: TDDialogButtonOptions(title: '取消', action: () => Navigator.pop(ctx)),
      ),
    );
  }

  void _showTextInput(String title, Function(String) onConfirm) {
    final c = TextEditingController();
    showDialog(
      context: context,
      builder: (ctx) => TDAlertDialog(
        title: title,
        contentWidget: TDInput(controller: c, hintText: '请输入'),
        leftBtn: TDDialogButtonOptions(title: '取消', action: () => Navigator.pop(ctx)),
        rightBtn: TDDialogButtonOptions(title: '确定', titleColor: AppColors.primary, action: () { onConfirm(c.text); Navigator.pop(ctx); }),
      ),
    );
  }

  void _showNumberInput(String title, Function(int) onConfirm) {
    final c = TextEditingController();
    showDialog(
      context: context,
      builder: (ctx) => TDAlertDialog(
        title: title,
        contentWidget: TextField(controller: c, keyboardType: TextInputType.number, decoration: const InputDecoration(hintText: '请输入数字')),
        leftBtn: TDDialogButtonOptions(title: '取消', action: () => Navigator.pop(ctx)),
        rightBtn: TDDialogButtonOptions(title: '确定', titleColor: AppColors.primary, action: () { onConfirm(int.tryParse(c.text) ?? 0); Navigator.pop(ctx); }),
      ),
    );
  }

  void _pickDate(Function(String) onPick) {
    showDatePicker(context: context, initialDate: DateTime.now(), firstDate: DateTime(2024), lastDate: DateTime(2028), locale: const Locale('zh'))
        .then((d) { if (d != null) onPick('${d.year}-${d.month.toString().padLeft(2, '0')}-${d.day.toString().padLeft(2, '0')}'); });
  }

  Widget _label(String t) => Text(t, style: const TextStyle(fontSize: AppFontSizes.body, color: AppColors.textSecondary));
  String _today() { final n = DateTime.now(); return '${n.year}-${n.month.toString().padLeft(2, '0')}-${n.day.toString().padLeft(2, '0')}'; }
}

class _DetailItem {
  final int id; final String category; final String categoryName; final int quantity;
  final String unit; final double unitPrice; final double amount; final String remark;
  const _DetailItem({required this.id, required this.category, required this.categoryName, required this.quantity, required this.unit, required this.unitPrice, required this.amount, required this.remark});
}