import 'package:lucide_icons_flutter/lucide_icons.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

import '../../core/responsive/responsive.dart';
import '../../core/theme/app_dims.g.dart';
import '../../core/theme/app_tokens.dart';
import '../../core/theme/context_tokens.dart';
import '../../core/utils/date_util.dart';
import '../../widgets/wheel_date_picker.dart';
import '../../core/theme/app_fonts.dart';

/// 录单页整体版式（对齐原型 stock-in.html：`.page-head` + `.form-wrap` + `.form-foot`）。
///
/// 出库 / 入库两屏共用此壳：固定顶部页头、可滚动的表单主区（提示条 + 单据信息 +
/// 商品明细）、固定底部合计栏。窄屏自动收窄内边距、页头/底栏动作切到 [mobileActions]。
class OrderFormShell extends StatelessWidget {
  final String title;
  final Widget? statusBadge;
  final VoidCallback onBack;

  /// 桌面页头 / 底栏动作（同一组按钮两处呈现，对齐原型 desk 组）。
  final List<Widget> deskActions;

  /// 窄屏页头动作（主操作 + 溢出菜单）。
  final List<Widget> mobileActions;

  final Widget? notice;
  final Widget docHead;
  final Widget detailHead;
  final Widget detail;
  final String rowsLabel; // 明细 N 行
  final String totalText; // 已格式化 ¥
  final String? profitText; // 合计利润（出库·仅管理员；null 不渲染）
  final bool loading;

  const OrderFormShell({
    super.key,
    required this.title,
    required this.onBack,
    required this.deskActions,
    required this.mobileActions,
    required this.docHead,
    required this.detailHead,
    required this.detail,
    required this.rowsLabel,
    required this.totalText,
    this.profitText,
    this.statusBadge,
    this.notice,
    this.loading = false,
  });

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    final mobile = context.isMobile;
    return Scaffold(
      backgroundColor: t.bg,
      body: Column(
        children: [
          // ── 页头（.page-head）──
          Padding(
            padding: mobile
                ? const EdgeInsets.fromLTRB(8, 13, 16, 10)
                : const EdgeInsets.fromLTRB(18, 16, 26, 14),
            child: Row(
              children: [
                IconButton(
                  icon: Icon(LucideIcons.chevronLeft, size: 22, color: t.muted),
                  onPressed: onBack,
                  tooltip: '返回',
                  visualDensity: VisualDensity.compact,
                ),
                const SizedBox(width: 6),
                Text(title,
                    style: TextStyle(
                        fontSize: mobile ? AppDims.fsH2 : AppDims.fsH1,
                        fontWeight: FontWeight.w700,
                        color: t.title)),
                if (statusBadge != null) ...[
                  const SizedBox(width: 12),
                  statusBadge!,
                ],
                const Spacer(),
                if (mobile)
                  ...mobileActions
                else
                  Wrap(spacing: 10, children: deskActions),
              ],
            ),
          ),
          // ── 表单主区（.form-wrap，可滚动）──
          Expanded(
            child: loading
                ? const Center(child: CircularProgressIndicator())
                : SingleChildScrollView(
                    padding: mobile
                        ? const EdgeInsets.fromLTRB(16, 0, 16, 14)
                        : const EdgeInsets.fromLTRB(26, 0, 26, 18),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.stretch,
                      children: [
                        if (notice != null) notice!,
                        docHead,
                        const SizedBox(height: 4),
                        detailHead,
                        detail,
                      ],
                    ),
                  ),
          ),
          // ── 底部合计栏（.form-foot）──
          Container(
            padding: mobile
                ? const EdgeInsets.symmetric(horizontal: 16, vertical: 12)
                : const EdgeInsets.symmetric(horizontal: 26, vertical: 13),
            decoration: BoxDecoration(
              color: t.surface,
              border: Border(top: BorderSide(color: t.border)),
            ),
            child: Row(
              children: [
                Text(rowsLabel,
                    style: TextStyle(fontSize: AppDims.fsSm, color: t.muted)),
                const Spacer(),
                if (profitText != null) ...[
                  Text('合计利润 ',
                      style:
                          TextStyle(fontSize: AppDims.fsBody, color: t.muted)),
                  Text(profitText!,
                      style: TextStyle(
                          fontSize: AppDims.fsTitle,
                          color:
                              profitText!.contains('-') ? t.danger : t.success,
                          fontFamily: AppFonts.mono,
                          fontFamilyFallback: AppFonts.monoFallback,
                          fontWeight: FontWeight.w700)),
                  const SizedBox(width: 18),
                ],
                Text('合计金额 ',
                    style: TextStyle(fontSize: AppDims.fsBody, color: t.muted)),
                Text(totalText,
                    style: TextStyle(
                        fontSize: 24,
                        color: t.accent,
                        fontFamily: AppFonts.mono,
                        fontFamilyFallback: AppFonts.monoFallback,
                        fontWeight: FontWeight.w700,
                        letterSpacing: 0.3)),
                if (!mobile) ...[
                  const SizedBox(width: 16),
                  Wrap(spacing: 10, children: deskActions),
                ],
              ],
            ),
          ),
        ],
      ),
    );
  }
}

/// 单据信息卡（.dochead）：可折叠，标题行 + 收起态摘要 + 4 列字段网格 + 备注。
class DocHeadCard extends StatefulWidget {
  final List<Widget> fields; // 4 个 DocField
  final Widget remark;
  final String summary; // 折叠态摘要（仓库 · 往来单位 · 日期）
  const DocHeadCard({
    super.key,
    required this.fields,
    required this.remark,
    required this.summary,
  });

  @override
  State<DocHeadCard> createState() => _DocHeadCardState();
}

class _DocHeadCardState extends State<DocHeadCard> {
  bool _folded = false;

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    final mobile = context.isMobile;
    return Container(
      margin: const EdgeInsets.only(top: 0, bottom: 14),
      padding:
          EdgeInsets.symmetric(horizontal: 18, vertical: _folded ? 13 : 16),
      decoration: BoxDecoration(
        color: t.surface,
        border: Border.all(color: t.border),
        borderRadius: BorderRadius.circular(AppDims.rLg),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          Row(
            children: [
              Text('单据信息',
                  style: TextStyle(
                      fontSize: AppDims.fsTitle,
                      fontWeight: FontWeight.w600,
                      color: t.heading)),
              if (_folded) ...[
                const SizedBox(width: 18),
                Expanded(
                  child: Text(widget.summary,
                      overflow: TextOverflow.ellipsis,
                      style:
                          TextStyle(fontSize: AppDims.fsBody, color: t.muted)),
                ),
              ] else
                const Spacer(),
              InkWell(
                onTap: () => setState(() => _folded = !_folded),
                child: Padding(
                  padding:
                      const EdgeInsets.symmetric(horizontal: 4, vertical: 2),
                  child: Row(mainAxisSize: MainAxisSize.min, children: [
                    Text(_folded ? '展开' : '收起',
                        style:
                            TextStyle(fontSize: AppDims.fsSm, color: t.muted)),
                    const SizedBox(width: 5),
                    Icon(
                        _folded
                            ? LucideIcons.chevronDown
                            : LucideIcons.chevronUp,
                        size: 14,
                        color: t.muted),
                  ]),
                ),
              ),
            ],
          ),
          if (!_folded) ...[
            const SizedBox(height: 14),
            if (mobile)
              Column(
                children: [
                  for (final f in widget.fields)
                    Padding(
                        padding: const EdgeInsets.only(bottom: 14), child: f),
                ],
              )
            else
              LayoutBuilder(builder: (context, c) {
                const gap = 14.0;
                final w = (c.maxWidth - gap * 3) / 4;
                return Wrap(
                  spacing: gap,
                  runSpacing: gap,
                  children: [
                    for (final f in widget.fields) SizedBox(width: w, child: f),
                  ],
                );
              }),
            const SizedBox(height: 14),
            widget.remark,
          ],
        ],
      ),
    );
  }
}

/// 单据信息里单个字段（label + 必填星 + 控件），对齐 `.field`。
class DocField extends StatelessWidget {
  final String label;
  final bool required;
  final Widget child;
  const DocField(
      {super.key,
      required this.label,
      required this.child,
      this.required = false});

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      mainAxisSize: MainAxisSize.min,
      children: [
        Row(children: [
          Text(label, style: TextStyle(fontSize: AppDims.fsSm, color: t.muted)),
          if (required)
            Text(' *',
                style: TextStyle(fontSize: AppDims.fsSm, color: t.danger)),
        ]),
        const SizedBox(height: 6),
        child,
      ],
    );
  }
}

/// 只读值框（.ro-val）：入库员/出库员等只读展示。
class RoValue extends StatelessWidget {
  final String text;
  const RoValue(this.text, {super.key});
  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    return Container(
      height: 38,
      alignment: Alignment.centerLeft,
      padding: const EdgeInsets.symmetric(horizontal: 11),
      decoration: BoxDecoration(
        color: t.bg,
        border: Border.all(color: t.borderSubtle),
        borderRadius: BorderRadius.circular(AppDims.rMd),
      ),
      child:
          Text(text, style: TextStyle(fontSize: AppDims.fsBody, color: t.text)),
    );
  }
}

/// 明细区标题行（.detail-head）：标题 + 键盘提示 + 右侧动作。
class DetailHead extends StatelessWidget {
  final List<Widget> actions;
  const DetailHead({super.key, required this.actions});

  static String modKey() =>
      (defaultTargetPlatform == TargetPlatform.macOS && !kIsWeb) ? '⌘' : 'Ctrl';

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    final mobile = context.isMobile;
    final mod = modKey();
    return Padding(
      padding: const EdgeInsets.only(bottom: 10),
      child: Row(
        children: [
          Text('商品明细',
              style: TextStyle(
                  fontSize: AppDims.fsTitle,
                  fontWeight: FontWeight.w600,
                  color: t.heading)),
          if (!mobile) ...[
            const SizedBox(width: 12),
            Flexible(
              child: Wrap(
                crossAxisAlignment: WrapCrossAlignment.center,
                spacing: 6,
                children: [
                  const _Kbd('Enter'),
                  _hintTxt(t, '下一格 · 末格自动加行 ·'),
                  _Kbd('$mod D'),
                  _hintTxt(t, '复制行 ·'),
                  _Kbd('$mod Enter'),
                  _hintTxt(t, '提交'),
                ],
              ),
            ),
          ],
          const Spacer(),
          ...actions,
        ],
      ),
    );
  }

  Widget _hintTxt(AppTokens t, String s) =>
      Text(s, style: TextStyle(fontSize: AppDims.fsSm, color: t.faint));
}

class _Kbd extends StatelessWidget {
  final String label;
  const _Kbd(this.label);
  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 5, vertical: 1),
      decoration: BoxDecoration(
        color: t.bg,
        border: Border.all(color: t.border),
        borderRadius: BorderRadius.circular(AppDims.rSm),
      ),
      child: Text(label,
          style: TextStyle(
              fontSize: AppDims.fsXs,
              fontFamily: AppFonts.mono,
              fontFamilyFallback: AppFonts.monoFallback,
              color: t.muted)),
    );
  }
}

/// 明细网格列描述（表头 + 宽度 + 对齐 + 必填星）。
class GridCol {
  final String key;
  final String label;
  final double? width; // null → 占满剩余（grow）
  final bool num;
  final bool req;
  const GridCol(this.key, this.label,
      {this.width, this.num = false, this.req = false});
}

/// 明细网格表（.grid）：粘性表头 + 行 + 底部「添加商品」。
/// 列内容由 [cellBuilder] 按 (rowIndex, colKey) 提供，两屏各自实现。
class OrderGridTable extends StatelessWidget {
  final List<GridCol> columns;
  final int rowCount;
  final Widget Function(int rowIndex, String colKey) cellBuilder;
  final bool Function(int rowIndex) rowHasError;
  final VoidCallback? onAddRow;
  const OrderGridTable({
    super.key,
    required this.columns,
    required this.rowCount,
    required this.cellBuilder,
    required this.rowHasError,
    this.onAddRow,
  });

  double get _minWidth {
    double fixed = 0;
    int grows = 0;
    for (final c in columns) {
      if (c.width != null) {
        fixed += c.width!;
      } else {
        grows++;
      }
    }
    return fixed + grows * 180;
  }

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    return Container(
      decoration: BoxDecoration(
        color: t.surface,
        border: Border.all(color: t.border),
        borderRadius: BorderRadius.circular(AppDims.rLg),
      ),
      clipBehavior: Clip.antiAlias,
      child: LayoutBuilder(builder: (context, c) {
        final overflow = c.maxWidth < _minWidth;
        final width = overflow ? _minWidth : c.maxWidth;
        final table = SizedBox(
          width: width,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              _header(t),
              for (var i = 0; i < rowCount; i++) _row(t, i),
            ],
          ),
        );
        return Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            overflow
                ? SingleChildScrollView(
                    scrollDirection: Axis.horizontal, child: table)
                : table,
            if (onAddRow != null) _addRow(t),
          ],
        );
      }),
    );
  }

  Widget _cellWrap(GridCol col, Widget child) {
    final aligned = Align(
      alignment: col.num ? Alignment.centerRight : Alignment.centerLeft,
      child: child,
    );
    if (col.width != null) return SizedBox(width: col.width, child: aligned);
    return Expanded(child: aligned);
  }

  Widget _header(AppTokens t) {
    return Container(
      color: t.thBg,
      padding: const EdgeInsets.symmetric(vertical: 10),
      child: Row(
        children: [
          for (final col in columns)
            _cellWrap(
              col,
              Padding(
                padding: const EdgeInsets.symmetric(horizontal: 10),
                child: Text.rich(
                  TextSpan(
                    children: [
                      TextSpan(text: col.label),
                      if (col.req)
                        TextSpan(text: ' *', style: TextStyle(color: t.danger)),
                    ],
                  ),
                  textAlign: col.num ? TextAlign.right : TextAlign.left,
                  style: TextStyle(
                      fontSize: AppDims.fsSm,
                      color: t.muted,
                      fontWeight: FontWeight.w600),
                ),
              ),
            ),
        ],
      ),
    );
  }

  Widget _row(AppTokens t, int i) {
    final err = rowHasError(i);
    return Container(
      decoration: BoxDecoration(
        border: Border(bottom: BorderSide(color: t.borderSubtle)),
        boxShadow: err
            ? [
                BoxShadow(
                    color: t.danger,
                    offset: const Offset(3, 0),
                    spreadRadius: -2)
              ]
            : null,
      ),
      child: IntrinsicHeight(
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.center,
          children: [
            for (final col in columns)
              _cellWrap(
                col,
                Padding(
                  padding: EdgeInsets.symmetric(
                      horizontal: col.key == 'act' ? 0 : 6, vertical: 4),
                  child: cellBuilder(i, col.key),
                ),
              ),
          ],
        ),
      ),
    );
  }

  Widget _addRow(AppTokens t) {
    return InkWell(
      onTap: onAddRow,
      child: Container(
        padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 11),
        decoration: BoxDecoration(
            border: Border(top: BorderSide(color: t.borderSubtle))),
        child: Row(children: [
          Icon(LucideIcons.plus, size: 16, color: t.primary),
          const SizedBox(width: 8),
          Text('添加商品',
              style: TextStyle(
                  fontSize: AppDims.fsBody,
                  color: t.primary,
                  fontWeight: FontWeight.w600)),
          const SizedBox(width: 8),
          Text('末格 Enter 自动加行',
              style: TextStyle(
                  fontSize: AppDims.fsXs,
                  fontFamily: AppFonts.mono,
                  fontFamilyFallback: AppFonts.monoFallback,
                  color: t.faint)),
        ]),
      ),
    );
  }
}

/// 网格内文本输入（.gci）：透明、32 高、聚焦描边。数值列右对齐等宽。
class GciField extends StatelessWidget {
  final TextEditingController controller;
  final FocusNode? focusNode;
  final bool num;
  final bool money;
  final String hint;
  final bool hasError;
  final bool enabled;
  final ValueChanged<String>? onChanged;
  final VoidCallback? onEnter; // Enter 推进下一格
  final bool Function({required bool backward})? onTab;
  const GciField({
    super.key,
    required this.controller,
    this.focusNode,
    this.num = false,
    this.money = false,
    this.hint = '',
    this.hasError = false,
    this.enabled = true,
    this.onChanged,
    this.onEnter,
    this.onTab,
  });

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    return Focus(
      focusNode: focusNode,
      onKeyEvent: (node, e) {
        if (e is! KeyDownEvent) return KeyEventResult.ignored;
        if (e.logicalKey == LogicalKeyboardKey.tab) {
          final back = HardwareKeyboard.instance.isShiftPressed;
          final handled = onTab?.call(backward: back) ?? false;
          return handled ? KeyEventResult.handled : KeyEventResult.ignored;
        }
        return KeyEventResult.ignored;
      },
      child: Builder(builder: (context) {
        return TextField(
          controller: controller,
          enabled: enabled,
          textAlign: num ? TextAlign.right : TextAlign.left,
          keyboardType:
              num ? const TextInputType.numberWithOptions(decimal: true) : null,
          inputFormatters: num
              ? [FilteringTextInputFormatter.allow(RegExp(r'^\d*\.?\d{0,2}'))]
              : null,
          onChanged: onChanged,
          onSubmitted: (_) => onEnter?.call(),
          style: TextStyle(
              fontSize: AppDims.fsBody,
              color: t.text,
              fontFamily: num ? 'monospace' : null),
          cursorColor: t.primary,
          decoration: InputDecoration(
            isCollapsed: true,
            contentPadding:
                const EdgeInsets.symmetric(horizontal: 8, vertical: 8),
            hintText: hint,
            hintStyle: TextStyle(fontSize: AppDims.fsBody, color: t.faint),
            prefixText: money ? '¥' : null,
            prefixStyle: TextStyle(fontSize: AppDims.fsBody, color: t.muted),
            filled: false,
            border: _b(Colors.transparent),
            enabledBorder: _b(hasError ? t.danger : Colors.transparent),
            focusedBorder: _b(t.primary),
          ),
        );
      }),
    );
  }

  OutlineInputBorder _b(Color c) => OutlineInputBorder(
        borderRadius: BorderRadius.circular(5),
        borderSide: BorderSide(color: c),
      );
}

/// 只读单元格文本（.ro）：系列/规格/成本价等出库只读列。
class RoCell extends StatelessWidget {
  final String text;
  final bool num;
  final Color? color;
  const RoCell(this.text, {super.key, this.num = false, this.color});
  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 8),
      child: Text(text.isEmpty ? '—' : text,
          textAlign: num ? TextAlign.right : TextAlign.left,
          style: TextStyle(
              fontSize: AppDims.fsBody,
              color: color ?? (text.isEmpty ? t.faint : t.muted),
              fontFamily: num ? 'monospace' : null)),
    );
  }
}

/// 金额单元格（.amt）：正常等宽粗体；[pending] 时橙色「待定价」。
class AmountCell extends StatelessWidget {
  final double amount;
  final bool pending;
  const AmountCell({super.key, required this.amount, this.pending = false});
  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    if (pending) {
      return Padding(
        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
        child: Text('待定价',
            textAlign: TextAlign.right,
            style: TextStyle(
                fontSize: AppDims.fsBody,
                color: t.warn,
                fontWeight: FontWeight.w600)),
      );
    }
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
      child: Text('¥${amount.toStringAsFixed(2)}',
          textAlign: TextAlign.right,
          style: TextStyle(
              fontSize: AppDims.fsBody,
              color: t.heading,
              fontFamily: AppFonts.mono,
              fontFamilyFallback: AppFonts.monoFallback,
              fontWeight: FontWeight.w600)),
    );
  }
}

/// 行操作图标组（.gact-in）：展开(可选)/复制/删除。
class RowActions extends StatelessWidget {
  final bool? expanded; // null → 不显示展开
  final VoidCallback? onToggleExpand;
  final bool expandHighlight;
  final VoidCallback onCopy;
  final VoidCallback? onDelete;
  const RowActions({
    super.key,
    this.expanded,
    this.onToggleExpand,
    this.expandHighlight = false,
    required this.onCopy,
    this.onDelete,
  });

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    return Row(
      mainAxisAlignment: MainAxisAlignment.center,
      mainAxisSize: MainAxisSize.min,
      children: [
        if (expanded != null)
          _icon(
            expanded! ? LucideIcons.chevronUp : LucideIcons.chevronDown,
            expandHighlight ? t.primary : t.muted,
            onToggleExpand,
            '选填项',
          ),
        _icon(LucideIcons.copy, t.muted, onCopy, '复制本行'),
        _icon(LucideIcons.trash2, onDelete == null ? t.faint : t.muted,
            onDelete, '删除'),
      ],
    );
  }

  // 紧凑图标按钮：24×24 命中区，不走 IconButton 的 48px 触摸目标（会撑破窄操作列）。
  Widget _icon(IconData ic, Color color, VoidCallback? onTap, String tip) =>
      Tooltip(
        message: tip,
        child: InkWell(
          onTap: onTap,
          borderRadius: BorderRadius.circular(4),
          child: SizedBox(
            width: 24,
            height: 24,
            child: Icon(ic, size: 16, color: color),
          ),
        ),
      );
}

/// 内联日期格（.datefield / .gci-date）：点选或 Enter 打开日历，值等宽显示。
class DsDateCell extends StatefulWidget {
  final String? value; // yyyy-MM-dd
  final ValueChanged<String?> onChanged;
  final FocusNode? focusNode;
  final bool cell; // true=.gci-date 网格样式；false=.datefield 独立样式
  final bool hasError;
  final bool enabled;
  final VoidCallback? onPicked; // 选完推进下一格
  final bool Function({required bool backward})? onTab;
  const DsDateCell({
    super.key,
    required this.value,
    required this.onChanged,
    this.focusNode,
    this.cell = false,
    this.hasError = false,
    this.enabled = true,
    this.onPicked,
    this.onTab,
  });

  @override
  State<DsDateCell> createState() => _DsDateCellState();
}

class _DsDateCellState extends State<DsDateCell> {
  // 浮层锚定到字段下方（对齐原型 datewheel.js：pop.style.top = field.bottom + 4），
  // 非居中弹窗，无遮罩——点字段外任意处收起（TapRegion.onTapOutside）。
  final _link = LayerLink();
  OverlayEntry? _entry;
  bool get _open => _entry != null;

  @override
  void dispose() {
    _removeOverlay();
    super.dispose();
  }

  void _toggle() {
    if (_open) {
      _close();
    } else {
      _openOverlay();
    }
  }

  void _openOverlay() {
    if (_open || !widget.enabled) return;
    final init = parseYmd(widget.value) ?? DateTime.now();
    _entry = OverlayEntry(
      builder: (_) => Positioned(
        width: 248,
        child: CompositedTransformFollower(
          link: _link,
          showWhenUnlinked: false,
          targetAnchor: Alignment.bottomLeft,
          followerAnchor: Alignment.topLeft,
          offset: const Offset(0, 4),
          child: TapRegion(
            onTapOutside: (_) => _close(),
            child: WheelDatePanel(
              initial: init,
              onCommit: (d) {
                widget.onChanged(formatYmd(d));
                _close();
                widget.onPicked?.call();
              },
            ),
          ),
        ),
      ),
    );
    Overlay.of(context).insert(_entry!);
    setState(() {});
  }

  void _close() {
    _removeOverlay();
    if (mounted) setState(() {});
  }

  void _removeOverlay() {
    _entry?.remove();
    _entry = null;
  }

  @override
  Widget build(BuildContext context) {
    final t = context.tokens;
    final has = widget.value != null && widget.value!.isNotEmpty;
    final height = widget.cell ? 32.0 : 38.0;
    return CompositedTransformTarget(
      link: _link,
      child: Focus(
        focusNode: widget.focusNode,
        onKeyEvent: (node, e) {
          if (e is! KeyDownEvent) return KeyEventResult.ignored;
          final k = e.logicalKey;
          if (k == LogicalKeyboardKey.enter ||
              k == LogicalKeyboardKey.numpadEnter ||
              k == LogicalKeyboardKey.space) {
            _toggle();
            return KeyEventResult.handled;
          }
          if (k == LogicalKeyboardKey.escape) {
            if (_open) {
              _close();
              return KeyEventResult.handled;
            }
            return KeyEventResult.ignored;
          }
          if (k == LogicalKeyboardKey.tab) {
            final back = HardwareKeyboard.instance.isShiftPressed;
            if (_open) _close();
            final handled = widget.onTab?.call(backward: back) ?? false;
            return handled ? KeyEventResult.handled : KeyEventResult.ignored;
          }
          return KeyEventResult.ignored;
        },
        child: Builder(builder: (context) {
          final active = Focus.of(context).hasFocus || _open;
          return GestureDetector(
            behavior: HitTestBehavior.opaque,
            onTap: widget.enabled
                ? () {
                    widget.focusNode?.requestFocus();
                    _toggle();
                  }
                : null,
            child: Container(
              height: height,
              padding: const EdgeInsets.symmetric(horizontal: 10),
              decoration: BoxDecoration(
                color: widget.cell
                    ? (active ? t.surface : Colors.transparent)
                    : t.surface,
                border: Border.all(
                  color: widget.hasError
                      ? t.danger
                      : (active
                          ? t.primary
                          : (widget.cell ? Colors.transparent : t.border)),
                ),
                borderRadius:
                    BorderRadius.circular(widget.cell ? 5 : AppDims.rMd),
              ),
              child: Row(children: [
                Expanded(
                  child: Text(
                    has ? widget.value! : '选择日期',
                    overflow: TextOverflow.ellipsis,
                    style: TextStyle(
                        fontSize: AppDims.fsBody,
                        color: has ? t.text : t.faint,
                        fontFamily: has ? 'monospace' : null),
                  ),
                ),
                Icon(LucideIcons.calendar, size: 15, color: t.faint),
              ]),
            ),
          );
        }),
      ),
    );
  }
}

// ── 键盘流：跨格推进 / 回退 ─────────────────────────────────────────────────
/// 从 [fromField] 之后找本行第一个空的必填格聚焦；本行满足则找后续行；
/// 末行末格则 [onAddRow]（新行自动聚焦首格）。对齐原型 advance()。
void advanceFocus({
  required int rowIndex,
  required String fromField,
  required int rowCount,
  required List<String> fields, // 可聚焦字段顺序
  required bool Function(String field) isRequired,
  required bool Function(int row, String field) isEmpty,
  required void Function(int row, String field) focusCell,
  required VoidCallback onAddRow,
}) {
  final start = fields.indexOf(fromField) + 1;
  for (var k = start; k < fields.length; k++) {
    if (isRequired(fields[k]) && isEmpty(rowIndex, fields[k])) {
      focusCell(rowIndex, fields[k]);
      return;
    }
  }
  for (var i = rowIndex + 1; i < rowCount; i++) {
    for (final f in fields) {
      if (isRequired(f) && isEmpty(i, f)) {
        focusCell(i, f);
        return;
      }
    }
  }
  if (rowIndex == rowCount - 1) {
    onAddRow();
  } else {
    focusCell(rowIndex + 1, fields.first);
  }
}

/// 回退到上一格（本行前一格，或上一行末格）。对齐原型 retreat()。
void retreatFocus({
  required int rowIndex,
  required String fromField,
  required List<String> fields,
  required void Function(int row, String field) focusCell,
}) {
  final k = fields.indexOf(fromField) - 1;
  if (k >= 0) {
    focusCell(rowIndex, fields[k]);
  } else if (rowIndex > 0) {
    focusCell(rowIndex - 1, fields.last);
  }
}