// lib/pages/new/main_page.dart
import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart' show rootBundle;
import 'package:qhd_prevention/common/route_service.dart';
import 'package:qhd_prevention/http/modules/appmenu_api.dart';
import 'package:qhd_prevention/pages/badge_manager.dart';
import 'package:qhd_prevention/pages/home/home_page.dart';
import 'package:qhd_prevention/pages/my_appbar.dart';
import 'package:qhd_prevention/pages/notif/notif_page.dart';
import 'package:qhd_prevention/services/heartbeat_service.dart';
import 'package:qhd_prevention/tools/tools.dart';

import 'mine/mine_page.dart';

/// 用于向子树公布当前 tab 索引
class CurrentTabNotifier extends InheritedWidget {
  final int currentIndex;
  const CurrentTabNotifier({
    required this.currentIndex,
    required Widget child,
    Key? key,
  }) : super(key: key, child: child);

  static CurrentTabNotifier? of(BuildContext context) {
    return context.dependOnInheritedWidgetOfExactType<CurrentTabNotifier>();
  }

  @override
  bool updateShouldNotify(covariant CurrentTabNotifier oldWidget) {
    return oldWidget.currentIndex != currentIndex;
  }
}

class MainPage extends StatefulWidget {
  const MainPage({Key? key, required this.isChooseFirm}) : super(key: key);
  final bool isChooseFirm;

  @override
  _MainPageState createState() => _MainPageState();
}

class _MainPageState extends State<MainPage> with WidgetsBindingObserver {
  int _currentIndex = 0;
  final GlobalKey<HomePageState> _homeKey = GlobalKey<HomePageState>();
  final GlobalKey<NotifPageState> _notifKey = GlobalKey<NotifPageState>();
  final GlobalKey<MinePageState> _mineKey = GlobalKey<MinePageState>();

  // 固定页面顺序（不要修改顺序，否则对应 _tabVisibility 的索引会错）
  late final List<Widget> _pages;

  // 存储每个固定Tab是否可见（对应 _pages 的顺序）
  // [首页, 通知, 我的]
  late List<bool> _tabVisibility;

  // 添加 BadgeManager 实例
  late final BadgeManager _badgeManager;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
    _badgeManager = BadgeManager();
    _badgeManager.addListener(_onBadgeChanged);
    // 初始化 BadgeManager
    if (widget.isChooseFirm) {
      _badgeManager.initAllModules();
    }


    // 初始化固定页面（顺序固定） — **这里保持你要求的构造不变**
    _pages = <Widget>[
      HomePage(key: _homeKey, isChooseFirm: widget.isChooseFirm),
      NotifPage(key: _notifKey),
      MinePage(key: _mineKey, isChooseFirm: widget.isChooseFirm),
    ];

    // 初始化时默认隐藏，等待路由加载后再决定显示哪些 tab
    _tabVisibility = [false, false, false];

    // 监听 RouteService 的更新：当路由数据加载/变更时更新可见性
    RouteService().addListener(_onRoutesUpdated);

    // 拉取路由（优先接口，失败则回退本地 assets）
    _getRoute();
  }

  /// 拉取路由：优先通过接口获取；如果接口失败或返回异常，回退到 assets/route/routes.txt
  Future<void> _getRoute() async {
    try {
      Map? route;
      // 接口获取
      // try {
      // LoadingDialogHelper.show(message: '加载中...');

      //   final res = await AppMenuApi.getAppMenu();
      //   if (res != null && res['success'] == true && res['data'] is List) {
      //     route = res;
      //   } else {
      //     debugPrint('AppMenuApi.getAppMenu returned no data or failed; fallback to local assets.');
      //   }
      // } catch (e) {
      //   debugPrint('AppMenuApi.getAppMenu error: $e -> fallback to local assets.');
      // }
      // 本地获取
      try {
        final routeString = await loadFromAssets();
        route = jsonDecode(routeString) as Map<String, dynamic>;
      } catch (e) {
        debugPrint('loadFromAssets error: $e');
      }

      if (route != null && route['data'] is List) {
        final data = route['data'] as List<dynamic>;
        RouteService().initializeRoutes(data);
        // initializeRoutes 内部会 notifyListeners -> _onRoutesUpdated 被调用
      } else {
        debugPrint('No valid route data to initialize RouteService.');
      }
    } catch (e) {
      debugPrint('获取路由配置失败: $e');
    } finally {
      LoadingDialogHelper.hide();
    }
  }

  Future<String> loadFromAssets() async {
    return await rootBundle.loadString('assets/route/routes.txt');
  }

  void _onRoutesUpdated() {
    // 路由服务更新时重新计算三个模块的可见性
    _updateTabVisibilityFromRoutes();
  }

  /// 根据 RouteService 中解析的路由来设置 _tabVisibility
  /// 规则：
  /// - 首页：menuPerms == 'dashboard'
  /// - 通知：menuPerms == 'notice'
  /// - 我的：menuPerms == 'my-center'
  void _updateTabVisibilityFromRoutes() {
    final routeService = RouteService();

    // 使用 mainTabs，如果为空（尚未有路由或后端返回空），保持当前 _tabVisibility（即不自动显示）
    final mainTabs = routeService.mainTabs;
    if (mainTabs.isEmpty) {
      return;
    }

    bool homeVisible = false;
    bool notifVisible = false;
    bool mineVisible = false;

    for (final m in mainTabs) {
      final perms = (m.menuPerms ?? '').toString();
      if (!homeVisible && perms == 'dashboard' && m.visible) {
        homeVisible = true;
      }
      if (!notifVisible && perms == 'notice'&& m.visible) {
        notifVisible = true;
      }
      if (!mineVisible && perms == 'my-center'&& m.visible) {
        mineVisible = true;
      }
      if (homeVisible && notifVisible && mineVisible) break;
    }

    // 后端未匹配到就隐藏（不兜底）
    setState(() {
      _tabVisibility = [homeVisible, widget.isChooseFirm ? notifVisible : false, mineVisible];

      // 若当前激活的 tab 被隐藏，则切换到第一个可见 tab（若没有可见 tab，则保持当前索引为 0）
      if (!_isIndexVisible(_currentIndex)) {
        final first = _firstVisibleIndexOrDefault(_currentIndex);
        _currentIndex = first;
      }
    });
  }

  // 返回第一个可见 tab 的索引；如果没有可见项，返回给定的 fallback（默认0）
  int _firstVisibleIndexOrDefault([int fallback = 0]) {
    for (int i = 0; i < _tabVisibility.length; i++) {
      if (_tabVisibility[i]) return i;
    }
    return fallback;
  }

  bool _isIndexVisible(int index) {
    if (index < 0 || index >= _tabVisibility.length) return false;
    return _tabVisibility[index];
  }

  @override
  void dispose() {
    // 移除监听
    _badgeManager.removeListener(_onBadgeChanged);
    RouteService().removeListener(_onRoutesUpdated);
    WidgetsBinding.instance.removeObserver(this);
    HeartbeatService().stop();
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    super.didChangeAppLifecycleState(state);
    switch (state) {
      case AppLifecycleState.resumed:
        HeartbeatService().resume();
        break;
      case AppLifecycleState.paused:
      case AppLifecycleState.inactive:
      case AppLifecycleState.detached:
      case AppLifecycleState.hidden:
        HeartbeatService().pause();
        break;
    }
  }

  Widget _buildIconWithBadge({required Widget icon, required int badgeCount}) {
    if (badgeCount <= 0) return icon;
    return Stack(
      clipBehavior: Clip.none,
      children: [
        icon,
        Positioned(
          right: -12,
          top: -4,
          child: Container(
            padding: const EdgeInsets.symmetric(horizontal: 5, vertical: 1),
            decoration: BoxDecoration(
              color: Colors.red,
              borderRadius: BorderRadius.circular(8),
            ),
            constraints: const BoxConstraints(minWidth: 16, minHeight: 16),
            child: Center(
              child: Text(
                '$badgeCount',
                style: const TextStyle(
                  color: Colors.white,
                  fontSize: 11,
                  height: 1,
                ),
                textAlign: TextAlign.center,
              ),
            ),
          ),
        ),
      ],
    );
  }

  // 将原始索引(固定顺序 0..n) 转为 可见索引 (visiblePages 索引)
  // 若 originalIndex 在当前不可见，则返回第一个可见的索引（若无可见则返回 0）
  int _originalToVisibleIndex(int originalIndex, List<bool> visibility) {
    int visibleIndex = 0;
    for (int i = 0; i < visibility.length; i++) {
      if (!visibility[i]) continue;
      if (i == originalIndex) return visibleIndex;
      visibleIndex++;
    }
    // originalIndex 不可见 -> 返回第一个可见索引（如果没有可见返回 0）
    return visibility.contains(true) ? 0 : 0;
  }

  // 将可见索引映射回原始索引（用于 BottomNavigationBar 的 onTap）
  // 若 visibleIndex 超界，返回第一个可见原始索引或 0
  int _visibleToOriginalIndex(int visibleIndex, List<bool> visibility) {
    int count = 0;
    for (int i = 0; i < visibility.length; i++) {
      if (!visibility[i]) continue;
      if (count == visibleIndex) return i;
      count++;
    }
    // 若没有找到，返回第一个可见原始索引或 0
    for (int i = 0; i < visibility.length; i++) {
      if (visibility[i]) return i;
    }
    return 0;
  }

  @override
  Widget build(BuildContext context) {
    // 使用 _badgeManager 而不是 BadgeManager()
    final bm = _badgeManager;

    // 构建可见的底部导航项与页面（基于 _tabVisibility）
    final List<BottomNavigationBarItem> visibleItems = [];
    final List<Widget> visiblePages = [];

    for (int i = 0; i < _pages.length; i++) {
      if (_tabVisibility[i]) {
        switch (i) {
          case 0:
            visibleItems.add(BottomNavigationBarItem(
              icon: Image.asset('assets/tabbar/basics.png', width: 24, height: 24),
              activeIcon: Image.asset('assets/tabbar/basics_cur.png', width: 24, height: 24),
              label: '首页',
            ));
            visiblePages.add(_pages[i]);
            break;
          case 1:
            visibleItems.add(BottomNavigationBarItem(
              icon: _buildIconWithBadge(
                icon: Image.asset('assets/tabbar/works.png', width: 24, height: 24),
                badgeCount: bm.notifCount,
              ),
              activeIcon: _buildIconWithBadge(
                icon: Image.asset('assets/tabbar/works_cur.png', width: 24, height: 24),
                badgeCount: bm.notifCount,
              ),
              label: '通知',
            ));
            visiblePages.add(_pages[i]);
            break;
          case 2:
            visibleItems.add(BottomNavigationBarItem(
              icon: Image.asset('assets/tabbar/my.png', width: 24, height: 24),
              activeIcon: Image.asset('assets/tabbar/my_cur.png', width: 24, height: 24),
              label: '我的',
            ));
            visiblePages.add(_pages[i]);
            break;
        }
      }
    }

    // 如果没有任何可见页面，body 显示空占位（按你之前要求不兜底）
    final bool hasVisiblePages = visiblePages.isNotEmpty;

    // 将当前索引映射到可见Tab的索引（用于 IndexedStack/BottomNavigationBar）
    final visibleCurrentIndex = _originalToVisibleIndex(_currentIndex, _tabVisibility);

    // ---------- 关键：根据 visibleItems 个数选择底栏渲染方式 ----------
    Widget? bottomBarWidget;
    if (visibleItems.length >= 2) {
      // 正常使用 BottomNavigationBar（至少 2 个 item）
      bottomBarWidget = BottomNavigationBar(
        currentIndex: visibleCurrentIndex,
        type: BottomNavigationBarType.fixed,
        selectedItemColor: Colors.blue,
        unselectedItemColor: Colors.grey,
        onTap: (visibleIndex) {
          final originalIndex = _visibleToOriginalIndex(visibleIndex, _tabVisibility);
          setState(() => _currentIndex = originalIndex);
        },
        items: visibleItems,
      );
    } else if (visibleItems.length == 1) {
      // 自定义单个 tab 底栏（避免 BottomNavigationBar 的断言）
      final single = visibleItems[0];
      final singleVisibleOriginalIndex = _visibleToOriginalIndex(0, _tabVisibility);
      final isSelected = _currentIndex == singleVisibleOriginalIndex;

      // 取选中或未选中的 icon 小部件
      final Widget iconWidget = isSelected && single.activeIcon != null ? single.activeIcon! : single.icon;

      bottomBarWidget = Material(
        elevation: 8,
        child: InkWell(
          onTap: () {
            setState(() {
              _currentIndex = singleVisibleOriginalIndex;
            });
          },
          child: Container(
            height: kBottomNavigationBarHeight,
            color: Colors.white,
            child: Center(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  // 图标（上）
                  SizedBox(
                    width: 28,
                    height: 28,
                    child: Center(child: iconWidget),
                  ),
                  const SizedBox(height: 4),
                  // 文本（下）
                  Text(
                    single.label ?? '',
                    style: TextStyle(
                      color: isSelected ? Colors.blue : Colors.grey,
                      fontSize: 12,
                    ),
                  ),
                ],
              ),
            ),
          ),
        ),
      );
    } else {
      // 没有可见项 -> 不显示底栏
      bottomBarWidget = null;
    }

    return CurrentTabNotifier(
      currentIndex: _currentIndex,
      child: Scaffold(
        appBar: null,
        body: hasVisiblePages
            ? IndexedStack(
          index: visibleCurrentIndex,
          children: visiblePages,
        )
            : const SizedBox.shrink(),
        bottomNavigationBar: bottomBarWidget,
      ),
    );
  }

  void _onBadgeChanged() {
    // 当角标数据变化时，只更新需要重建的部分
    if (mounted) setState(() {});
  }
}