import 'package:lucide_icons_flutter/lucide_icons.dart';
import 'dart:async';

import '../core/utils/dialog_util.dart';
import 'package:flutter/material.dart';
import '../core/responsive/responsive.dart';
import 'package:lpinyin/lpinyin.dart';
import '../core/theme/context_tokens.dart';
import 'ds/ds_atoms.dart';
import 'ds/ds_toast.dart';

class OptionItem {
  final int id;
  final String name;
  final String? code;
  // 拼音索引，构造时预计算
  late final String _fullPinyin;
  late final String _initials;

  OptionItem({required this.id, required this.name, this.code}) {
    _fullPinyin = PinyinHelper.getPinyinE(name, separator: '', defPinyin: '')
        .toLowerCase();
    _initials = PinyinHelper.getShortPinyin(name).toLowerCase();
  }

  bool matches(String kw) {
    final k = kw.toLowerCase();
    return name.toLowerCase().contains(k) ||
        (_fullPinyin.isNotEmpty && _fullPinyin.contains(k)) ||
        (_initials.isNotEmpty && _initials.contains(k)) ||
        (code?.toLowerCase().contains(k) ?? false);
  }
}

/// 点击后弹出搜索对话框的下拉选择框
class SearchableOptionField extends StatelessWidget {
  final List<OptionItem> options;
  final int? selectedId;
  final String hint;
  final String dialogTitle;
  final ValueChanged<int?> onChanged;
  final bool isRequired;
  final bool isDense;

  /// 带框样式（OutlineInputBorder）；默认 false 沿用主题下划线。
  /// 详细搜索等「表单里与文本框并列」的场景传 true，视觉统一为带框。
  final bool bordered;

  /// 可选：搜索无匹配时「新增到基础数据」。回调收到当前关键字（用户可在确认框里改），
  /// 创建成功返回新选项 id（自动选中），失败/取消返回 null。为空则不显示新增入口。
  final Future<int?> Function(String keyword)? onCreate;

  /// 可选：服务端搜索。提供时搜索框输入会 debounce 调它取结果（替代本地过滤）。
  final Future<List<OptionItem>> Function(String keyword)? onSearch;

  const SearchableOptionField({
    super.key,
    required this.options,
    required this.selectedId,
    required this.hint,
    required this.dialogTitle,
    required this.onChanged,
    this.isRequired = false,
    this.isDense = true,
    this.bordered = false,
    this.onCreate,
    this.onSearch,
  });

  String get _displayText {
    if (selectedId == null) return '';
    return options.where((o) => o.id == selectedId).firstOrNull?.name ?? '';
  }

  Future<void> _openDialog(BuildContext context) async {
    final result = await showDialog<int?>(
      context: context,
      builder: (_) => _SearchDialog(
        title: dialogTitle,
        options: options,
        selectedId: selectedId,
        onCreate: onCreate,
        onSearch: onSearch,
      ),
    );
    // result == -1 means "clear selection"
    if (result == -1) {
      onChanged(null);
    } else if (result != null) {
      onChanged(result);
    }
  }

  @override
  Widget build(BuildContext context) {
    final selected = selectedId != null;
    return FormField<int>(
      initialValue: selectedId,
      validator: isRequired ? (v) => (selectedId == null ? '请选择' : null) : null,
      builder: (state) {
        return InkWell(
          onTap: () => _openDialog(context),
          borderRadius: BorderRadius.circular(4),
          child: InputDecorator(
            decoration: InputDecoration(
              isDense: isDense,
              border: bordered ? const OutlineInputBorder() : null,
              errorText: state.errorText,
              suffixIcon: selected
                  ? GestureDetector(
                      onTap: () => onChanged(null),
                      child: Icon(LucideIcons.x,
                          size: 14, color: context.tokens.muted),
                    )
                  : Icon(LucideIcons.chevronDown,
                      size: 16, color: context.tokens.muted),
            ),
            isEmpty: !selected,
            child: Text(
              selected ? _displayText : hint,
              style: TextStyle(
                fontSize: 12,
                color: selected ? context.tokens.text : context.tokens.muted,
              ),
              overflow: TextOverflow.ellipsis,
            ),
          ),
        );
      },
    );
  }
}

class _SearchDialog extends StatefulWidget {
  final String title;
  final List<OptionItem> options;
  final int? selectedId;
  final Future<int?> Function(String keyword)? onCreate;
  final Future<List<OptionItem>> Function(String keyword)? onSearch;
  const _SearchDialog({
    required this.title,
    required this.options,
    this.selectedId,
    this.onCreate,
    this.onSearch,
  });

  @override
  State<_SearchDialog> createState() => _SearchDialogState();
}

class _SearchDialogState extends State<_SearchDialog> {
  final _ctrl = TextEditingController();
  String _keyword = '';
  bool _creating = false;
  List<OptionItem>? _serverItems; // 服务端搜索结果（null=尚未搜索，用 widget.options）
  bool _searching = false;
  Timer? _debounce;

  void _onSearchChanged(String v) {
    setState(() => _keyword = v);
    if (widget.onSearch == null) return;
    _debounce?.cancel();
    _debounce = Timer(const Duration(milliseconds: 300), () async {
      setState(() => _searching = true);
      try {
        final res = await widget.onSearch!(v.trim());
        if (mounted) setState(() => _serverItems = res);
      } finally {
        if (mounted) setState(() => _searching = false);
      }
    });
  }

  @override
  void dispose() {
    _debounce?.cancel();
    _ctrl.dispose();
    super.dispose();
  }

  /// 「新增到基础数据」流程：确认（名称可改）→ onCreate → 成功则带新 id 关闭搜索框。
  Future<void> _createFlow() async {
    final kw = _keyword.trim();
    if (widget.onCreate == null || kw.isEmpty) return;
    final nameCtrl = TextEditingController(text: kw);
    final confirmed = await showAppDialog<bool>(
      context: context,
      builder: (_) => AlertDialog(
        title: const Text('新增到基础数据', style: TextStyle(fontSize: 16)),
        content: SizedBox(
          width: context.dialogWidth(320),
          child: TextField(
            controller: nameCtrl,
            autofocus: true,
            decoration: const InputDecoration(hintText: '名称', isDense: true),
          ),
        ),
        actions: [
          DsButton('取消', onPressed: () => Navigator.of(context).pop(false)),
          DsButton('确认新增',
              variant: DsBtnVariant.primary,
              onPressed: () => Navigator.of(context).pop(true)),
        ],
      ),
    );
    if (confirmed != true) return;
    final name = nameCtrl.text.trim();
    if (name.isEmpty) return;
    setState(() => _creating = true);
    try {
      final newId = await widget.onCreate!(name);
      if (!mounted) return;
      if (newId != null) {
        Navigator.of(context).pop(newId); // 回填并自动选中
      } else {
        setState(() => _creating = false);
        showDsToast(context, '新增失败，请重试');
      }
    } catch (e) {
      if (!mounted) return;
      setState(() => _creating = false);
      showDsToast(context, '新增失败：$e');
    }
  }

  @override
  Widget build(BuildContext context) {
    final filtered = widget.onSearch != null
        ? (_serverItems ?? widget.options)
        : (_keyword.isEmpty
            ? widget.options
            : widget.options.where((o) => o.matches(_keyword)).toList());
    final kw = _keyword.trim();
    final hasExact =
        filtered.any((o) => o.name.toLowerCase() == kw.toLowerCase());
    final canCreate = widget.onCreate != null && kw.isNotEmpty && !hasExact;

    return AlertDialog(
      title: Text(widget.title, style: const TextStyle(fontSize: 16)),
      contentPadding: const EdgeInsets.fromLTRB(16, 12, 16, 0),
      content: SizedBox(
        width: context.dialogWidth(300),
        height: 400,
        child: Column(
          children: [
            TextField(
              controller: _ctrl,
              autofocus: true,
              decoration: InputDecoration(
                hintText: '搜索...',
                prefixIcon: const Icon(LucideIcons.search, size: 18),
                suffixIcon: _searching
                    ? const Padding(
                        padding: EdgeInsets.all(10),
                        child: SizedBox(
                          width: 16,
                          height: 16,
                          child: CircularProgressIndicator(strokeWidth: 2),
                        ),
                      )
                    : null,
                isDense: true,
              ),
              onChanged: _onSearchChanged,
            ),
            const SizedBox(height: 8),
            Expanded(
              child: filtered.isEmpty
                  ? Center(
                      child: Text(
                        canCreate ? '无匹配结果，可新增到基础数据' : '无匹配结果',
                        style: TextStyle(color: context.tokens.muted),
                      ),
                    )
                  : ListView.builder(
                      itemCount: filtered.length,
                      itemBuilder: (_, i) {
                        final opt = filtered[i];
                        final isSelected = opt.id == widget.selectedId;
                        return ListTile(
                          dense: true,
                          title: Text(opt.name,
                              style: const TextStyle(fontSize: 13)),
                          subtitle: opt.code != null && opt.code!.isNotEmpty
                              ? Text(opt.code!,
                                  style: const TextStyle(fontSize: 11))
                              : null,
                          selected: isSelected,
                          selectedTileColor:
                              context.tokens.primary.withValues(alpha: 0.08),
                          onTap: () => Navigator.of(context).pop(opt.id),
                        );
                      },
                    ),
            ),
            if (canCreate)
              Align(
                alignment: Alignment.centerLeft,
                child: TextButton.icon(
                  onPressed: _creating ? null : _createFlow,
                  icon: _creating
                      ? const SizedBox(
                          width: 14,
                          height: 14,
                          child: CircularProgressIndicator(strokeWidth: 2),
                        )
                      : const Icon(LucideIcons.plus, size: 16),
                  label: Text('新增「$kw」到基础数据',
                      style: const TextStyle(fontSize: 12)),
                ),
              ),
          ],
        ),
      ),
      actions: [
        if (widget.selectedId != null)
          DsButton('清除选择', onPressed: () => Navigator.of(context).pop(-1)),
        DsButton('取消', onPressed: () => Navigator.of(context).pop(null)),
      ],
    );
  }
}