jiu/client/lib/widgets/ds/m_sheet.dart

// widgets/ds/m_sheet.dart — 统一移动底部 sheet（镜像原型 mobile-atoms .m-sheet）。
// 结构：grip(36×4) + 标题行(m-sheet-h：标题 + X) + 滚动体(m-sheet-b) + 可选底部操作条。
// max 高 86vh、顶部 r-xl 圆角、SelectionArea 可选中复制；键盘弹出自动避让。
import 'package:flutter/material.dart';
import 'package:lucide_icons_flutter/lucide_icons.dart';

import '../../core/responsive/responsive.dart';
import '../../core/theme/app_chrome.g.dart';
import '../../core/theme/app_dims.g.dart';
import '../../core/theme/context_tokens.dart';
import '../../core/utils/dialog_util.dart';

/// 打开中的移动 sheet 关闭器栈：壳层横滑手势据此判定——有 sheet 开着时
/// 「从左往右滑」关顶层 sheet，而不是切 tab / 退二级屏（2026-07-04 拍板）。
final List<VoidCallback> _openSheetClosers = [];
bool get hasOpenMSheet => _openSheetClosers.isNotEmpty;
void closeTopMSheet() {
  if (_openSheetClosers.isNotEmpty) _openSheetClosers.last();
}

/// 打开移动底部 sheet（对齐原型 mobile-shell openSheet）。
/// - [title] 为 null 时只渲染 grip，内容自带头部（详情抽屉复用场景）。
/// - [scrollable] true：内容包 SingleChildScrollView；false：内容自管布局
///   （需自带定界高度，如 SizedBox(height:…)，供 Column/Expanded 正常工作）。
/// - [actions] 底部固定操作条（原型 .m-actionbar 形态：横排等分按钮）。
Future<T?> showMSheet<T>(
  BuildContext context, {
  String? title,
  required WidgetBuilder builder,
  bool scrollable = true,
  double maxHeightFactor = 0.86,
  List<Widget>? actions,
}) {
  // 登记关闭器（壳层手势用）；sheet 结束（任何方式关闭）时注销。
  final nav = Navigator.of(context);
  void closer() {
    if (nav.canPop()) nav.pop();
  }

  _openSheetClosers.add(closer);
  return _showMSheetInner<T>(
    context,
    title: title,
    builder: builder,
    scrollable: scrollable,
    maxHeightFactor: maxHeightFactor,
    actions: actions,
  ).whenComplete(() => _openSheetClosers.remove(closer));
}

Future<T?> _showMSheetInner<T>(
  BuildContext context, {
  String? title,
  required WidgetBuilder builder,
  bool scrollable = true,
  double maxHeightFactor = 0.86,
  List<Widget>? actions,
}) {
  return showModalBottomSheet<T>(
    context: context,
    isScrollControlled: true,
    useSafeArea: true,
    backgroundColor: Colors.transparent,
    barrierColor: AppChrome.scrim, // .m-sheet-mask --scrim
    builder: (ctx) {
      final t = ctx.tokens;
      final maxH = MediaQuery.of(ctx).size.height * maxHeightFactor;
      final viewInsets = MediaQuery.of(ctx).viewInsets.bottom;
      return Padding(
        // 键盘弹出时整体上移（sheet 内含输入框场景）
        padding: EdgeInsets.only(bottom: viewInsets),
        child: Container(
          clipBehavior: Clip.antiAlias,
          constraints: BoxConstraints(maxHeight: maxH),
          decoration: BoxDecoration(
            color: t.surface,
            borderRadius:
                const BorderRadius.vertical(top: Radius.circular(AppDims.rXl)),
          ),
          // sheet 是独立 overlay（在 app_shell 的 SelectionArea 之外）→ 自带一层
          child: SelectionArea(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              crossAxisAlignment: CrossAxisAlignment.stretch,
              children: [
                // .grip
                Center(
                  child: Container(
                    width: 36,
                    height: 4,
                    margin: const EdgeInsets.only(top: 8, bottom: 2),
                    decoration: BoxDecoration(
                      color: t.border,
                      borderRadius: BorderRadius.circular(AppDims.rPill),
                    ),
                  ),
                ),
                if (title != null)
                  Container(
                    padding: const EdgeInsets.fromLTRB(16, 10, 16, 12),
                    decoration: BoxDecoration(
                      border:
                          Border(bottom: BorderSide(color: t.borderSubtle)),
                    ),
                    child: Row(children: [
                      Expanded(
                        child: Text(title,
                            style: TextStyle(
                                fontSize: AppDims.fsTitle,
                                fontWeight: FontWeight.w700,
                                color: t.heading)),
                      ),
                      InkWell(
                        onTap: () => Navigator.of(ctx).pop(),
                        child: Icon(LucideIcons.x, size: 20, color: t.muted),
                      ),
                    ]),
                  ),
                Flexible(
                  child: scrollable
                      ? SingleChildScrollView(
                          padding: const EdgeInsets.fromLTRB(16, 14, 16, 14),
                          child: Builder(builder: builder),
                        )
                      : Builder(builder: builder),
                ),
                if (actions != null)
                  Container(
                    padding: const EdgeInsets.fromLTRB(16, 12, 16, 12),
                    decoration: BoxDecoration(
                      border: Border(top: BorderSide(color: t.borderSubtle)),
                    ),
                    child: Row(children: [
                      for (var i = 0; i < actions.length; i++) ...[
                        if (i > 0) const SizedBox(width: 10),
                        Expanded(child: actions[i]),
                      ],
                    ]),
                  ),
              ],
            ),
          ),
        ),
      );
    },
  );
}

/// 自适应弹层：窄屏走底部 sheet，宽屏走既有 showAppDialog（Dialog 卡）。
/// 供各屏的筛选 / 轻表单 / 选项选择统一调用，减少 isMobile 样板分支。
Future<T?> showAdaptiveSheet<T>(
  BuildContext context, {
  required String title,
  required WidgetBuilder builder,
  List<Widget>? actions,
  double desktopWidth = 480,
}) {
  if (context.isMobile) {
    return showMSheet<T>(context,
        title: title, builder: builder, actions: actions);
  }
  return showAppDialog<T>(
    context: context,
    builder: (ctx) {
      final t = ctx.tokens;
      return Dialog(
        shape:
            RoundedRectangleBorder(borderRadius: BorderRadius.circular(AppDims.rLg)),
        child: SizedBox(
          width: ctx.dialogWidth(desktopWidth),
          child: Column(
            mainAxisSize: MainAxisSize.min,
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              Padding(
                padding: const EdgeInsets.fromLTRB(20, 18, 20, 0),
                child: Row(children: [
                  Expanded(
                    child: Text(title,
                        style: TextStyle(
                            fontSize: AppDims.fsTitle,
                            fontWeight: FontWeight.w700,
                            color: t.heading)),
                  ),
                  InkWell(
                    onTap: () => Navigator.of(ctx).pop(),
                    child: Icon(LucideIcons.x, size: 18, color: t.muted),
                  ),
                ]),
              ),
              Flexible(
                child: SingleChildScrollView(
                  padding: const EdgeInsets.fromLTRB(20, 14, 20, 18),
                  child: Builder(builder: builder),
                ),
              ),
              if (actions != null)
                Padding(
                  padding: const EdgeInsets.fromLTRB(20, 0, 20, 18),
                  child: Row(children: [
                    for (var i = 0; i < actions.length; i++) ...[
                      if (i > 0) const SizedBox(width: 10),
                      Expanded(child: actions[i]),
                    ],
                  ]),
                ),
            ],
          ),
        ),
      );
    },
  );
}