import 'dart:async';

import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:miaoji_zhang/shared/api/api_client.dart';
import 'package:miaoji_zhang/shared/api/business_api.dart';
import 'package:miaoji_zhang/shared/api/config_api.dart';
import 'package:miaoji_zhang/shared/services/current_ledger_store.dart';
import 'package:miaoji_zhang/shared/services/session_store.dart';
import 'package:miaoji_zhang/shared/services/transaction_events.dart';
import 'package:miaoji_zhang/shared/theme/app_theme.dart';
import 'package:miaoji_zhang/shared/widgets/category_icon.dart';
import 'package:miaoji_zhang/shared/widgets/app_icons.dart';
import 'package:miaoji_zhang/shared/widgets/async_error_view.dart';
import 'package:miaoji_zhang/shared/widgets/backend_status_icon.dart';
import 'package:miaoji_zhang/features/home/pages/tx_detail_page.dart';
import 'package:miaoji_zhang/features/home/pages/ledger_sheet.dart';
import 'package:miaoji_zhang/shared/services/shanghai_time.dart';

/// 首页明细（P1 / P20 空状态）
class HomePage extends StatefulWidget {
  const HomePage({super.key});

  @override
  State<HomePage> createState() => HomePageState();
}

class HomePageState extends State<HomePage> {
  MonthSummary? _summary;
  BudgetsData? _budgets;
  bool _loading = true;
  String? _error;
  late DateTime _month;
  int _loadRevision = 0;

  @override
  void initState() {
    super.initState();
    _month = ShanghaiTime.now;
    PublicConfigApi.companionNotifier.addListener(_refreshCompanion);
    TransactionEvents.revision.addListener(_refreshTransactions);
    CurrentLedgerStore.instance.addListener(_refreshLedger);
    unawaited(refresh());
  }

  void _refreshCompanion() {
    if (mounted) setState(() {});
  }

  void _refreshTransactions() {
    if (mounted) refresh();
  }

  void _refreshLedger() {
    if (mounted) refresh();
  }

  @override
  void dispose() {
    PublicConfigApi.companionNotifier.removeListener(_refreshCompanion);
    TransactionEvents.revision.removeListener(_refreshTransactions);
    CurrentLedgerStore.instance.removeListener(_refreshLedger);
    super.dispose();
  }

  Future<void> refresh() async {
    final revision = ++_loadRevision;
    setState(() {
      _loading = true;
      _error = null;
    });
    try {
      await CurrentLedgerStore.instance.loadCached();
      final localSummary = TxApi.monthLocal(_month.year, _month.month);
      final localBudgets = BudgetApi.getLocal(_month.year, _month.month);
      if (mounted && revision == _loadRevision) {
        setState(() {
          _summary = localSummary;
          _budgets = localBudgets;
        });
      }
    } catch (error) {
      if (mounted && revision == _loadRevision) {
        setState(() {
          _error = apiErrorMessage(error);
          _loading = false;
        });
      }
      return;
    }

    await Future.wait([
      () async {
        try {
          await CurrentLedgerStore.instance.refreshRemote();
        } catch (_) {}
      }(),
      () async {
        try {
          final summary = await TxApi.monthRemote(_month.year, _month.month);
          if (mounted && revision == _loadRevision) {
            setState(() => _summary = summary);
          }
        } catch (_) {}
      }(),
      () async {
        try {
          final budgets = await BudgetApi.getRemote(_month.year, _month.month);
          if (mounted && revision == _loadRevision) {
            setState(() => _budgets = budgets);
          }
        } catch (_) {}
      }(),
    ]);
    if (mounted && revision == _loadRevision) {
      setState(() => _loading = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final s = _summary;
    final budgets = _budgets;
    final session = SessionStore.instance;
    final showAiEntry = session.isGuest || session.aiEnabled;
    final budgetsByCategory = <int, BudgetItem>{
      for (final item in budgets?.categories ?? const <BudgetItem>[])
        if (item.categoryId != null) item.categoryId!: item,
    };
    if (!_loading && s == null && _error != null) {
      return Scaffold(
        body: SafeArea(
          child: AsyncErrorView(message: _error!, onRetry: refresh),
        ),
      );
    }
    return Scaffold(
      body: SafeArea(
        child: RefreshIndicator(
          onRefresh: refresh,
          color: AppTheme.primary,
          child: NotificationListener<ScrollNotification>(
            onNotification: (notification) {
              if (notification is ScrollStartNotification) {
                _SwipeReveal.closeOpen();
              }
              return false;
            },
            child: ListView(
              padding: const EdgeInsets.symmetric(horizontal: 16),
              children: [
                SizedBox(height: 8),
                Row(
                  children: [
                    GestureDetector(
                      onTap: () {
                        _month = DateTime(_month.year, _month.month - 1);
                        refresh();
                      },
                      child: Transform(
                        alignment: Alignment.center,
                        transform: Matrix4.rotationY(3.1416),
                        child: AppIcons.icon(
                          AppIcons.chevronRight,
                          size: 16,
                          color: context.jz.text3,
                        ),
                      ),
                    ),
                    SizedBox(width: 6),
                    GestureDetector(
                      onTap: () =>
                          LedgerSheet.show(context).then((_) => refresh()),
                      child: Row(
                        mainAxisSize: MainAxisSize.min,
                        children: [
                          Text(
                            CurrentLedgerStore.instance.currentName,
                            style: TextStyle(
                              fontSize: 16,
                              fontWeight: FontWeight.w700,
                            ),
                          ),
                          AppIcons.icon(
                            AppIcons.chevronDown,
                            size: 16,
                            color: context.jz.text3,
                          ),
                        ],
                      ),
                    ),
                    SizedBox(width: 6),
                    GestureDetector(
                      onTap: () {
                        _month = DateTime(_month.year, _month.month + 1);
                        refresh();
                      },
                      child: AppIcons.icon(
                        AppIcons.chevronRight,
                        size: 16,
                        color: context.jz.text3,
                      ),
                    ),
                    Spacer(),
                    BackendStatusIcon(onRetry: refresh),
                    IconButton(
                      icon: AppIcons.icon(
                        AppIcons.search,
                        size: 20,
                        color: context.jz.text2,
                      ),
                      onPressed: () => context.push('/search'),
                    ),
                  ],
                ),
                Text(
                  '${_month.year}年${_month.month}月',
                  style: TextStyle(fontSize: 11, color: context.jz.text3),
                ),
                SizedBox(height: 6),
                Container(
                  padding: const EdgeInsets.all(20),
                  decoration: BoxDecoration(
                    color: AppTheme.primary,
                    borderRadius: BorderRadius.circular(18),
                  ),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(
                        '${_month.month}月结余',
                        style: TextStyle(
                          fontSize: 12,
                          color: Colors.white.withValues(alpha: 0.85),
                        ),
                      ),
                      SizedBox(height: 5),
                      Text(
                        '¥ ${(s?.balance ?? 0).toStringAsFixed(2)}',
                        style: TextStyle(
                          fontSize: 30,
                          fontWeight: FontWeight.w700,
                          color: Colors.white,
                        ),
                      ),
                      SizedBox(height: 14),
                      Row(
                        children: [
                          _HeroCol(label: '收入', value: s?.income ?? 0),
                          _HeroCol(label: '支出', value: s?.expense ?? 0),
                          _HeroCol(
                            label: '笔数',
                            value: (s?.count ?? 0).toDouble(),
                            isCount: true,
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
                SizedBox(height: 12),
                if (budgets != null) ...[
                  _BudgetSummaryCard(
                    data: budgets,
                    onTap: () async {
                      await context.push('/budget');
                      refresh();
                    },
                  ),
                  SizedBox(height: 12),
                ],
                if (showAiEntry) ...[
                  GestureDetector(
                    onTap: () => context.go('/chat'),
                    child: Container(
                      padding: const EdgeInsets.symmetric(
                        horizontal: 13,
                        vertical: 11,
                      ),
                      decoration: BoxDecoration(
                        color: context.jz.card,
                        borderRadius: BorderRadius.circular(14),
                        border: Border.all(color: context.jz.line, width: 0.5),
                      ),
                      child: Row(
                        children: [
                          CircleAvatar(
                            radius: 19,
                            backgroundColor: AppTheme.ai,
                            child: AppIcons.icon(
                              AppIcons.avatarAsset(
                                PublicConfigApi.companionAvatarKey,
                              ),
                              size: 20,
                              color: Colors.white,
                            ),
                          ),
                          SizedBox(width: 11),
                          Expanded(
                            child: Column(
                              crossAxisAlignment: CrossAxisAlignment.start,
                              children: [
                                Text(
                                  PublicConfigApi.companionName,
                                  style: TextStyle(
                                    fontSize: 13,
                                    fontWeight: FontWeight.w600,
                                  ),
                                ),
                                Text(
                                  SessionStore.instance.shouldUseLocalOnly
                                      ? '登录并连接云端后可使用 AI 记账'
                                      : '说句话就能记账',
                                  style: TextStyle(
                                    fontSize: 11,
                                    color: context.jz.text2,
                                  ),
                                ),
                              ],
                            ),
                          ),
                          Container(
                            padding: const EdgeInsets.symmetric(
                              horizontal: 12,
                              vertical: 6,
                            ),
                            decoration: BoxDecoration(
                              color: context.jz.aiBackground,
                              borderRadius: BorderRadius.circular(16),
                            ),
                            child: Text(
                              '去聊天',
                              style: TextStyle(
                                fontSize: 12,
                                color: AppTheme.ai,
                                fontWeight: FontWeight.w600,
                              ),
                            ),
                          ),
                        ],
                      ),
                    ),
                  ),
                  SizedBox(height: 15),
                ],
                if (_loading && s == null)
                  Padding(
                    padding: EdgeInsets.only(top: 60),
                    child: Center(
                      child: CircularProgressIndicator(
                        color: AppTheme.primary,
                        strokeWidth: 2,
                      ),
                    ),
                  )
                else if (s == null || s.days.isEmpty)
                  _EmptyState(
                    aiEnabled: showAiEntry,
                    onAction: showAiEntry
                        ? () => context.go('/chat')
                        : () => context.push('/add'),
                    companionName: PublicConfigApi.companionName,
                    avatarKey: PublicConfigApi.companionAvatarKey,
                  )
                else ...[
                  Padding(
                    padding: EdgeInsets.only(left: 2, bottom: 9),
                    child: Text(
                      '最近账单',
                      style: TextStyle(
                        fontSize: 14,
                        fontWeight: FontWeight.w700,
                      ),
                    ),
                  ),
                  ...s.days.map(
                    (d) => _DayCard(
                      day: d,
                      onDeleted: refresh,
                      budgetsByCategory: budgetsByCategory,
                    ),
                  ),
                ],
                SizedBox(height: 12),
              ],
            ),
          ),
        ),
      ),
    );
  }
}

class _BudgetSummaryCard extends StatelessWidget {
  final BudgetsData data;
  final VoidCallback onTap;

  const _BudgetSummaryCard({required this.data, required this.onTap});

  @override
  Widget build(BuildContext context) {
    final total = data.total;
    final amount =
        total?.amount ??
        data.categories.fold<double>(0, (sum, item) => sum + item.amount);
    final spent =
        total?.spent ??
        data.categories.fold<double>(0, (sum, item) => sum + item.spent);
    final rawRatio = amount <= 0 ? 0.0 : spent / amount;
    final ratio = rawRatio.clamp(0.0, 1.0);
    final warningColor = rawRatio >= 1
        ? AppTheme.red
        : rawRatio >= 0.8
        ? AppTheme.orange
        : AppTheme.primary;

    return Material(
      color: context.jz.card,
      borderRadius: BorderRadius.circular(14),
      child: InkWell(
        onTap: onTap,
        borderRadius: BorderRadius.circular(14),
        child: Container(
          padding: const EdgeInsets.all(14),
          decoration: BoxDecoration(
            borderRadius: BorderRadius.circular(14),
            border: Border.all(color: context.jz.line, width: 0.5),
          ),
          child: amount <= 0
              ? Row(
                  children: [
                    Icon(
                      Icons.donut_small_rounded,
                      size: 22,
                      color: AppTheme.primary,
                    ),
                    SizedBox(width: 10),
                    Expanded(
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Text(
                            '本月预算',
                            style: TextStyle(
                              fontSize: 13,
                              fontWeight: FontWeight.w700,
                            ),
                          ),
                          Text(
                            '设一个可执行的消费边界',
                            style: TextStyle(
                              fontSize: 11,
                              color: context.jz.text3,
                            ),
                          ),
                        ],
                      ),
                    ),
                    Text(
                      '去设置',
                      style: TextStyle(
                        fontSize: 12,
                        color: AppTheme.primary,
                        fontWeight: FontWeight.w700,
                      ),
                    ),
                  ],
                )
              : Column(
                  children: [
                    Row(
                      children: [
                        Text(
                          total?.isRecurring == true ? '周期预算' : '本月预算',
                          style: TextStyle(
                            fontSize: 13,
                            fontWeight: FontWeight.w700,
                          ),
                        ),
                        Spacer(),
                        Text(
                          rawRatio >= 1
                              ? '已超 ¥${(spent - amount).toStringAsFixed(0)}'
                              : '剩余 ¥${(amount - spent).toStringAsFixed(0)}',
                          style: TextStyle(
                            fontSize: 11.5,
                            color: warningColor,
                            fontWeight: FontWeight.w700,
                          ),
                        ),
                      ],
                    ),
                    SizedBox(height: 9),
                    ClipRRect(
                      borderRadius: BorderRadius.circular(3),
                      child: LinearProgressIndicator(
                        value: ratio,
                        minHeight: 6,
                        backgroundColor: context.jz.line,
                        color: warningColor,
                      ),
                    ),
                    SizedBox(height: 7),
                    Row(
                      children: [
                        Text(
                          '已用 ¥${spent.toStringAsFixed(0)}',
                          style: TextStyle(
                            fontSize: 10.5,
                            color: context.jz.text3,
                          ),
                        ),
                        Spacer(),
                        Text(
                          '预算 ¥${amount.toStringAsFixed(0)} · ${(rawRatio * 100).toStringAsFixed(0)}%',
                          style: TextStyle(
                            fontSize: 10.5,
                            color: context.jz.text3,
                          ),
                        ),
                      ],
                    ),
                  ],
                ),
        ),
      ),
    );
  }
}

class _HeroCol extends StatelessWidget {
  final String label;
  final double value;
  final bool isCount;
  const _HeroCol({
    required this.label,
    required this.value,
    this.isCount = false,
  });
  @override
  Widget build(BuildContext context) {
    return Expanded(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            label,
            style: TextStyle(
              fontSize: 11,
              color: Colors.white.withValues(alpha: 0.85),
            ),
          ),
          SizedBox(height: 2),
          Text(
            isCount
                ? value.toInt().toString()
                : '¥ ${value.toStringAsFixed(2)}',
            style: TextStyle(
              fontSize: 14,
              fontWeight: FontWeight.w600,
              color: Colors.white,
            ),
          ),
        ],
      ),
    );
  }
}

class _EmptyState extends StatelessWidget {
  final VoidCallback onAction;
  final String companionName, avatarKey;
  final bool aiEnabled;

  const _EmptyState({
    required this.onAction,
    required this.aiEnabled,
    required this.companionName,
    required this.avatarKey,
  });

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 40),
      child: Column(
        children: [
          Container(
            width: 100,
            height: 100,
            decoration: BoxDecoration(
              shape: BoxShape.circle,
              color: aiEnabled
                  ? context.jz.aiBackground
                  : context.jz.primaryBackground,
            ),
            child: AppIcons.icon(
              aiEnabled ? AppIcons.avatarAsset(avatarKey) : AppIcons.wallet,
              size: 48,
              color: aiEnabled ? AppTheme.ai : AppTheme.primary,
            ),
          ),
          SizedBox(height: 16),
          Text(
            '还没有账单',
            style: TextStyle(fontSize: 15, fontWeight: FontWeight.w700),
          ),
          SizedBox(height: 6),
          Text(
            aiEnabled
                ? '跟我说句话就能记账，比如\n"早饭包子豆浆 6 块" · "打车 45"'
                : '点击下方按钮手动记录第一笔账单',
            textAlign: TextAlign.center,
            style: TextStyle(
              fontSize: 11.5,
              color: context.jz.text2,
              height: 1.7,
            ),
          ),
          SizedBox(height: 18),
          ElevatedButton.icon(
            style: ElevatedButton.styleFrom(
              backgroundColor: aiEnabled ? AppTheme.ai : AppTheme.primary,
              padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
            ),
            onPressed: onAction,
            icon: AppIcons.icon(
              aiEnabled ? AppIcons.chat : AppIcons.plus,
              size: 16,
              color: Colors.white,
            ),
            label: Text(aiEnabled ? '和${companionName}聊聊' : '记一笔'),
          ),
        ],
      ),
    );
  }
}

class _DayCard extends StatelessWidget {
  final DayGroup day;
  final VoidCallback onDeleted;
  final Map<int, BudgetItem> budgetsByCategory;
  const _DayCard({
    required this.day,
    required this.onDeleted,
    required this.budgetsByCategory,
  });
  @override
  Widget build(BuildContext context) {
    final now = ShanghaiTime.now;
    final isToday =
        day.date.year == now.year &&
        day.date.month == now.month &&
        day.date.day == now.day;
    return Container(
      margin: const EdgeInsets.only(bottom: 10),
      padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 2),
      decoration: BoxDecoration(
        color: context.jz.card,
        borderRadius: BorderRadius.circular(14),
        border: Border.all(color: context.jz.line, width: 0.5),
      ),
      child: Column(
        children: [
          Padding(
            padding: const EdgeInsets.symmetric(vertical: 9),
            child: Row(
              children: [
                Text(
                  isToday
                      ? '今天 · ${day.date.month}月${day.date.day}日'
                      : '${day.date.month}月${day.date.day}日',
                  style: TextStyle(fontSize: 11, color: context.jz.text3),
                ),
                Spacer(),
                Text(
                  [
                    if (day.income > 0) '收 ¥${day.income.toStringAsFixed(2)}',
                    if (day.expense > 0) '支 ¥${day.expense.toStringAsFixed(2)}',
                  ].join(' · '),
                  style: TextStyle(fontSize: 11, color: context.jz.text3),
                ),
              ],
            ),
          ),
          Divider(height: 0.5, color: context.jz.line),
          ...day.items.map(
            (t) => _TxRow(
              tx: t,
              onDeleted: onDeleted,
              budget: budgetsByCategory[t.categoryId],
            ),
          ),
        ],
      ),
    );
  }
}

class _TxRow extends StatelessWidget {
  final TxItem tx;
  final VoidCallback onDeleted;
  final BudgetItem? budget;
  const _TxRow({required this.tx, required this.onDeleted, this.budget});

  @override
  Widget build(BuildContext context) {
    final hh =
        '${tx.occurredAt.hour.toString().padLeft(2, '0')}:${tx.occurredAt.minute.toString().padLeft(2, '0')}';
    return _SwipeReveal(
      id: tx.id,
      onTap: () => Navigator.push(
        context,
        MaterialPageRoute(builder: (_) => TxDetailPage(tx: tx)),
      ),
      onDelete: () async {
        try {
          await TxApi.delete(tx.id);
          onDeleted();
          if (!context.mounted) return;
          ScaffoldMessenger.of(context)
            ..hideCurrentSnackBar()
            ..showSnackBar(
              SnackBar(
                behavior: SnackBarBehavior.floating,
                content: Text('已移入回收站'),
                action: SnackBarAction(
                  label: '撤销',
                  textColor: AppTheme.primary,
                  onPressed: () async {
                    try {
                      await TxApi.restore(tx.id);
                      onDeleted();
                    } catch (error) {
                      if (!context.mounted) return;
                      ScaffoldMessenger.of(context).showSnackBar(
                        SnackBar(content: Text(apiErrorMessage(error))),
                      );
                    }
                  },
                ),
              ),
            );
        } catch (error) {
          if (context.mounted) {
            ScaffoldMessenger.of(
              context,
            ).showSnackBar(SnackBar(content: Text(apiErrorMessage(error))));
          }
        }
      },
      child: Padding(
        padding: const EdgeInsets.symmetric(vertical: 10),
        child: Row(
          children: [
            CategoryIconBox(
              iconKey: tx.categoryIcon,
              colorKey: tx.categoryColor,
            ),
            SizedBox(width: 12),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text(
                    tx.note ?? tx.categoryName,
                    style: TextStyle(
                      fontSize: 13.5,
                      fontWeight: FontWeight.w500,
                    ),
                    maxLines: 1,
                    overflow: TextOverflow.ellipsis,
                  ),
                  SizedBox(height: 2),
                  Row(
                    children: [
                      Text(
                        hh,
                        style: TextStyle(
                          fontSize: 10.5,
                          color: context.jz.text3,
                        ),
                      ),
                      if (!tx.isIncome &&
                          budget != null &&
                          budget!.amount > 0 &&
                          budget!.spent / budget!.amount >= 0.8) ...[
                        SizedBox(width: 5),
                        Container(
                          padding: const EdgeInsets.symmetric(
                            horizontal: 6,
                            vertical: 1.5,
                          ),
                          decoration: BoxDecoration(
                            color: budget!.spent >= budget!.amount
                                ? context.jz.expenseBackground
                                : context.jz.warningBackground,
                            borderRadius: BorderRadius.circular(6),
                          ),
                          child: Text(
                            budget!.spent >= budget!.amount
                                ? '预算已超'
                                : '预算 ${(budget!.spent / budget!.amount * 100).toStringAsFixed(0)}%',
                            style: TextStyle(
                              fontSize: 9,
                              color: budget!.spent >= budget!.amount
                                  ? AppTheme.red
                                  : AppTheme.orange,
                              fontWeight: FontWeight.w700,
                            ),
                          ),
                        ),
                      ],
                      if (tx.isAi) ...[
                        SizedBox(width: 5),
                        Container(
                          padding: const EdgeInsets.symmetric(
                            horizontal: 6,
                            vertical: 1.5,
                          ),
                          decoration: BoxDecoration(
                            color: context.jz.aiBackground,
                            borderRadius: BorderRadius.circular(6),
                          ),
                          child: Text(
                            '✦ AI',
                            style: TextStyle(
                              fontSize: 9,
                              color: AppTheme.ai,
                              fontWeight: FontWeight.w600,
                            ),
                          ),
                        ),
                      ],
                    ],
                  ),
                ],
              ),
            ),
            Text(
              '${tx.isIncome ? '+' : '-'}${tx.amount.toStringAsFixed(2)}',
              style: TextStyle(
                fontSize: 14.5,
                fontWeight: FontWeight.w600,
                color: tx.isIncome ? AppTheme.primary : context.jz.text,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _SwipeReveal extends StatefulWidget {
  static const double actionWidth = 76;
  static final ValueNotifier<int?> _openId = ValueNotifier<int?>(null);

  final int id;
  final Widget child;
  final VoidCallback onTap;
  final Future<void> Function() onDelete;

  const _SwipeReveal({
    required this.id,
    required this.child,
    required this.onTap,
    required this.onDelete,
  });

  static void closeOpen() {
    _openId.value = null;
  }

  @override
  State<_SwipeReveal> createState() => _SwipeRevealState();
}

class _SwipeRevealState extends State<_SwipeReveal> {
  double _dragOffset = 0;
  bool _dragging = false;
  bool _deleting = false;

  void _startDrag(DragStartDetails details) {
    _dragging = true;
    _dragOffset = _SwipeReveal._openId.value == widget.id
        ? -_SwipeReveal.actionWidth
        : 0;
    if (_SwipeReveal._openId.value != widget.id) {
      _SwipeReveal.closeOpen();
    }
  }

  void _updateDrag(DragUpdateDetails details) {
    setState(() {
      _dragOffset = (_dragOffset + details.delta.dx).clamp(
        -_SwipeReveal.actionWidth,
        0,
      );
    });
  }

  void _endDrag(DragEndDetails details) {
    final reveal =
        _dragOffset <= -36 ||
        (details.primaryVelocity != null && details.primaryVelocity! < -500);
    _dragging = false;
    _SwipeReveal._openId.value = reveal ? widget.id : null;
    setState(() => _dragOffset = reveal ? -_SwipeReveal.actionWidth : 0);
  }

  Future<void> _delete() async {
    if (_deleting) return;
    setState(() => _deleting = true);
    _SwipeReveal.closeOpen();
    try {
      await widget.onDelete();
    } finally {
      if (mounted) setState(() => _deleting = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    return ValueListenableBuilder<int?>(
      valueListenable: _SwipeReveal._openId,
      builder: (_, openId, __) {
        final target = _dragging
            ? _dragOffset
            : openId == widget.id
            ? -_SwipeReveal.actionWidth
            : 0.0;
        return ClipRect(
          child: Stack(
            alignment: Alignment.centerRight,
            children: [
              Positioned.fill(
                child: Align(
                  alignment: Alignment.centerRight,
                  child: Semantics(
                    button: true,
                    label: '删除账单',
                    child: Material(
                      color: AppTheme.red,
                      child: InkWell(
                        onTap: _deleting ? null : _delete,
                        child: SizedBox(
                          width: _SwipeReveal.actionWidth,
                          child: Center(
                            child: _deleting
                                ? SizedBox(
                                    width: 18,
                                    height: 18,
                                    child: CircularProgressIndicator(
                                      strokeWidth: 2,
                                      color: Colors.white,
                                    ),
                                  )
                                : AppIcons.icon(
                                    AppIcons.trash,
                                    size: 20,
                                    color: Colors.white,
                                  ),
                          ),
                        ),
                      ),
                    ),
                  ),
                ),
              ),
              AnimatedContainer(
                duration: _dragging
                    ? Duration.zero
                    : const Duration(milliseconds: 180),
                curve: Curves.easeOutCubic,
                transform: Matrix4.translationValues(target, 0, 0),
                color: context.jz.card,
                child: GestureDetector(
                  behavior: HitTestBehavior.opaque,
                  onTap: openId == widget.id
                      ? _SwipeReveal.closeOpen
                      : widget.onTap,
                  onHorizontalDragStart: _startDrag,
                  onHorizontalDragUpdate: _updateDrag,
                  onHorizontalDragEnd: _endDrag,
                  onHorizontalDragCancel: () {
                    _dragging = false;
                    _SwipeReveal.closeOpen();
                  },
                  child: widget.child,
                ),
              ),
            ],
          ),
        );
      },
    );
  }
}