import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../../../models/app_version.dart';
import '../../../services/app_service.dart';
import '../../../services/api_client.dart';
import '../../../utils/formatters.dart';

/// 应用版本管理页。
class AppVersionPage extends ConsumerStatefulWidget {
  const AppVersionPage({super.key});

  @override
  ConsumerState<AppVersionPage> createState() => _AppVersionPageState();
}

class _AppVersionPageState extends ConsumerState<AppVersionPage> {
  final _searchController = TextEditingController();
  final _scrollController = ScrollController();

  List<AppVersion> _items = [];
  bool _loading = false;
  bool _hasMore = true;
  int _page = 1;
  String? _error;
  String _keyword = '';

  @override
  void initState() {
    super.initState();
    _scrollController.addListener(_onScroll);
    _loadData();
  }

  @override
  void dispose() {
    _searchController.dispose();
    _scrollController.removeListener(_onScroll);
    _scrollController.dispose();
    super.dispose();
  }

  void _onScroll() {
    if (_scrollController.position.pixels >=
            _scrollController.position.maxScrollExtent - 200 &&
        !_loading &&
        _hasMore) {
      _loadMore();
    }
  }

  Future<void> _loadData() async {
    setState(() {
      _loading = true;
      _error = null;
    });
    try {
      final list = await AppService().getAppVersionList(page: 1, limit: 20);
      if (!mounted) return;
      setState(() {
        _items = list;
        _loading = false;
        _hasMore = list.length >= 20;
        _page = 1;
      });
    } catch (e) {
      if (!mounted) return;
      setState(() {
        _loading = false;
        _error = _friendlyError(e);
      });
    }
  }

  Future<void> _loadMore() async {
    if (_loading) return;
    setState(() => _loading = true);
    try {
      final list = await AppService().getAppVersionList(page: _page + 1, limit: 20);
      if (!mounted) return;
      setState(() {
        _items.addAll(list);
        _loading = false;
        _hasMore = list.length >= 20;
        _page++;
      });
    } catch (_) {
      if (!mounted) return;
      setState(() => _loading = false);
    }
  }

  Future<void> _refresh() async {
    _page = 1;
    _hasMore = true;
    await _loadData();
  }

  String _friendlyError(Object e) {
    if (e is ApiException) return e.message;
    final msg = e.toString();
    if (msg.contains('404') ||
        msg.contains('DioException') ||
        msg.contains('SocketException')) {
      return '应用版本接口暂不可用，请联系管理员确认权限或接口地址';
    }
    return '加载失败：$msg';
  }

  void _showForm({AppVersion? editing}) {
    final isEdit = editing != null;
    final appNameCtrl = TextEditingController(text: editing?.appName ?? '');
    final packageCtrl = TextEditingController(text: editing?.packageName ?? '');
    final versionNameCtrl = TextEditingController(text: editing?.versionName ?? '');
    final versionCodeCtrl =
        TextEditingController(text: editing?.versionCode.toString() ?? '');
    final apkUrlCtrl = TextEditingController(text: editing?.apkUrl ?? '');
    final orgIdCtrl = TextEditingController(text: editing?.orgId ?? '');
    final groupIdCtrl = TextEditingController(text: editing?.groupId ?? '');
    int statusValue = editing?.status ?? 0;

    showModalBottomSheet(
          useSafeArea: true,
      context: context,
      isScrollControlled: true,
      builder: (ctx) => StatefulBuilder(
        builder: (ctx, setSheet) => Padding(
          padding: EdgeInsets.only(
            bottom: MediaQuery.of(ctx).viewInsets.bottom,
          ),
          child: Padding(
            padding: const EdgeInsets.all(16),
            child: SingleChildScrollView(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  Text(isEdit ? '编辑版本' : '新增版本',
                      style: Theme.of(ctx).textTheme.titleMedium),
                  const SizedBox(height: 16),
                  TextField(
                      controller: appNameCtrl,
                      decoration: const InputDecoration(
                          labelText: '应用名称', border: OutlineInputBorder())),
                  const SizedBox(height: 12),
                  TextField(
                      controller: packageCtrl,
                      decoration: const InputDecoration(
                          labelText: '包名', border: OutlineInputBorder())),
                  const SizedBox(height: 12),
                  TextField(
                      controller: versionNameCtrl,
                      decoration: const InputDecoration(
                          labelText: '版本名', border: OutlineInputBorder())),
                  const SizedBox(height: 12),
                  TextField(
                      controller: versionCodeCtrl,
                      keyboardType: TextInputType.number,
                      decoration: const InputDecoration(
                          labelText: '版本号', border: OutlineInputBorder())),
                  const SizedBox(height: 12),
                  TextField(
                      controller: apkUrlCtrl,
                      decoration: const InputDecoration(
                          labelText: 'APK下载地址', border: OutlineInputBorder())),
                  const SizedBox(height: 12),
                  TextField(
                      controller: orgIdCtrl,
                      decoration: const InputDecoration(
                          labelText: '组织ID', border: OutlineInputBorder())),
                  const SizedBox(height: 12),
                  TextField(
                      controller: groupIdCtrl,
                      decoration: const InputDecoration(
                          labelText: '分组ID', border: OutlineInputBorder())),
                  const SizedBox(height: 12),
                  DropdownButtonFormField<int>(
                    value: statusValue,
                    decoration: const InputDecoration(
                        labelText: '状态', border: OutlineInputBorder()),
                    items: const [
                      DropdownMenuItem(value: 0, child: Text('正常')),
                      DropdownMenuItem(value: 1, child: Text('禁用')),
                    ],
                    onChanged: (v) {
                      if (v != null) setSheet(() => statusValue = v);
                    },
                  ),
                  const SizedBox(height: 16),
                  FilledButton(
                    onPressed: () async {
                      final data = <String, dynamic>{
                        if (isEdit) 'id': editing!.id,
                        'appName': appNameCtrl.text,
                        'packageName': packageCtrl.text,
                        'versionName': versionNameCtrl.text,
                        'versionCode': int.tryParse(versionCodeCtrl.text) ?? 0,
                        'apkUrl': apkUrlCtrl.text,
                        'orgId': orgIdCtrl.text,
                        'groupId': groupIdCtrl.text,
                        'status': statusValue,
                      };
                      try {
                        if (isEdit) {
                          await AppService().updateAppVersion(data);
                        } else {
                          await AppService().saveAppVersion(data);
                        }
                        if (!ctx.mounted) return;
                        Navigator.pop(ctx);
                        _refresh();
                        if (!mounted) return;
                        ScaffoldMessenger.of(context).showSnackBar(
                          const SnackBar(content: Text('保存成功')),
                        );
                      } catch (e) {
                        if (!ctx.mounted) return;
                        ScaffoldMessenger.of(ctx).showSnackBar(
                          SnackBar(content: Text(e is ApiException ? e.message : '保存失败')),
                        );
                      }
                    },
                    child: const Text('保存'),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }

  Future<void> _delete(String id) async {
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('确认删除'),
        content: const Text('确定要删除此版本吗？'),
        actions: [
          TextButton(onPressed: () => Navigator.pop(ctx, false), child: const Text('取消')),
          TextButton(onPressed: () => Navigator.pop(ctx, true), child: const Text('删除')),
        ],
      ),
    );
    if (confirmed != true) return;
    try {
      await AppService().deleteAppVersion([int.tryParse(id) ?? 0]);
      _refresh();
      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('删除成功')));
    } catch (e) {
      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(e is ApiException ? e.message : '删除失败')),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(automaticallyImplyLeading: false, title: const Text('应用版本管理')),
      body: Column(
        children: [
          Padding(
            padding: const EdgeInsets.fromLTRB(16, 8, 16, 8),
            child: TextField(
              controller: _searchController,
              decoration: InputDecoration(
                hintText: '搜索应用名称',
                prefixIcon: const Icon(Icons.search),
                suffixIcon: _keyword.isEmpty
                    ? null
                    : IconButton(
                        icon: const Icon(Icons.clear),
                        onPressed: () {
                          _searchController.clear();
                          setState(() => _keyword = '');
                        },
                      ),
              ),
              onSubmitted: (v) => setState(() => _keyword = v),
            ),
          ),
          Expanded(
            child: _error != null
                ? Center(child: Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      Text(_error!),
                      const SizedBox(height: 8),
                      FilledButton.tonal(onPressed: _refresh, child: const Text('重试')),
                    ],
                  ))
                : RefreshIndicator(
                    onRefresh: _refresh,
                    child: _items.isEmpty && !_loading
                        ? const Center(child: Text('暂无数据'))
                        : ListView.builder(
                            controller: _scrollController,
                            physics: const AlwaysScrollableScrollPhysics(),
                            itemCount: _items.length + (_loading ? 1 : 0),
                            itemBuilder: (ctx, i) {
                              if (i >= _items.length) {
                                return const Padding(
                                  padding: EdgeInsets.all(16),
                                  child: Center(child: CircularProgressIndicator()),
                                );
                              }
                              final item = _items[i];
                              if (_keyword.isNotEmpty &&
                                  !item.appName.toLowerCase().contains(_keyword.toLowerCase())) {
                                return const SizedBox.shrink();
                              }
                              return Card(
                                child: ListTile(
                                  title: Text(item.appName,
                                      style: const TextStyle(fontWeight: FontWeight.w600)),
                                  subtitle: Column(
                                    crossAxisAlignment: CrossAxisAlignment.start,
                                    children: [
                                      const SizedBox(height: 4),
                                      Text('包名: ${item.packageName}'),
                                      Text('版本: ${item.versionName} (${item.versionCode})'),
                                      if (item.createTime != null)
                                        Text('创建: ${Formatters.formatDateTime(item.createTime!)}'),
                                      const SizedBox(height: 4),
                                      Chip(
                                        label: Text(item.status == 0 ? '正常' : '禁用'),
                                        visualDensity: VisualDensity.compact,
                                      ),
                                    ],
                                  ),
                                  trailing: PopupMenuButton<String>(
                                    onSelected: (v) {
                                      if (v == 'edit') _showForm(editing: item);
                                      if (v == 'delete') _delete(item.id);
                                    },
                                    itemBuilder: (_) => [
                                      const PopupMenuItem(value: 'edit', child: Text('编辑')),
                                      const PopupMenuItem(value: 'delete', child: Text('删除')),
                                    ],
                                  ),
                                ),
                              );
                            },
                          ),
                  ),
          ),
        ],
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () => _showForm(),
        child: const Icon(Icons.add),
      ),
    );
  }
}