import 'dart:math';
import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import '../../core/router/routes.dart';
import '../../core/constants/app_colors.dart';
import '../../core/updater/update_service.dart';
import '../../core/updater/channels/self_hosted_updater.dart';

class MainShell extends StatefulWidget {
  final Widget child;

  const MainShell({super.key, required this.child});

  @override
  State<MainShell> createState() => _MainShellState();
}

class _MainShellState extends State<MainShell> with WidgetsBindingObserver {
  /// 下次允许检查更新的时间（static 防止 widget rebuild 重置）
  static DateTime? _nextCheckAllowedTime;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _checkForUpdateIfNeeded();
    });
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      _checkForUpdateIfNeeded();
    }
  }

  Future<void> _checkForUpdateIfNeeded() async {
    final now = DateTime.now();

    // 如果从未检查过，或者已过冷却时间，则检查
    if (_nextCheckAllowedTime == null || now.isAfter(_nextCheckAllowedTime!)) {
      // 设置下次允许检查时间（90-300秒随机间隔）
      final randomSeconds = 90 + Random().nextInt(211);
      _nextCheckAllowedTime = now.add(Duration(seconds: randomSeconds));

      // 延迟3秒，避免启动时干扰用户
      await Future.delayed(const Duration(seconds: 3));
      if (!mounted) return;

      try {
        final result = await UpdateService.instance.checkForUpdate();
        if (!mounted) return;

        if (result.hasUpdate && result.versionInfo != null) {
          await SelfHostedUpdater.show(
            context,
            versionInfo: result.versionInfo!,
            isForceUpdate: result.versionInfo!.isForceUpdate,
          );
        }
      } catch (e) {
        debugPrint('[MainShell] 检查更新失败: $e');
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final isDark = AppColors.isDark(context);

    return Scaffold(
      body: widget.child,
      bottomNavigationBar: Container(
        decoration: BoxDecoration(
          color: AppColors.cardOf(context),
          boxShadow: [
            BoxShadow(
              color: isDark
                  ? Colors.black.withOpacity(0.3)
                  : Colors.black.withOpacity(0.05),
              blurRadius: 10,
              offset: const Offset(0, -2),
            ),
          ],
        ),
        child: SafeArea(
          top: false,
          child: Container(
            height: 56,
            padding: const EdgeInsets.symmetric(horizontal: 16),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                _buildNavItem(
                  context,
                  icon: Icons.favorite_outline,
                  activeIcon: Icons.favorite,
                  label: '贡献值',
                  index: 0,
                ),
                _buildNavItem(
                  context,
                  icon: Icons.swap_horiz_outlined,
                  activeIcon: Icons.swap_horiz,
                  label: '兑换',
                  index: 1,
                ),
                _buildNavItem(
                  context,
                  icon: Icons.account_balance_wallet_outlined,
                  activeIcon: Icons.account_balance_wallet,
                  label: '资产',
                  index: 2,
                ),
                _buildNavItem(
                  context,
                  icon: Icons.person_outline,
                  activeIcon: Icons.person,
                  label: '我的',
                  index: 3,
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }

  Widget _buildNavItem(
    BuildContext context, {
    required IconData icon,
    required IconData activeIcon,
    required String label,
    required int index,
  }) {
    final currentIndex = _calculateSelectedIndex(context);
    final isSelected = currentIndex == index;
    final inactiveColor = AppColors.textMutedOf(context);

    return GestureDetector(
      onTap: () => _onItemTapped(index, context),
      behavior: HitTestBehavior.opaque,
      child: SizedBox(
        width: 64,
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Icon(
              isSelected ? activeIcon : icon,
              size: 24,
              color: isSelected ? AppColors.orange : inactiveColor,
            ),
            const SizedBox(height: 4),
            Text(
              label,
              style: TextStyle(
                fontSize: 11,
                fontWeight: isSelected ? FontWeight.w600 : FontWeight.w400,
                color: isSelected ? AppColors.orange : inactiveColor,
              ),
            ),
          ],
        ),
      ),
    );
  }

  int _calculateSelectedIndex(BuildContext context) {
    final location = GoRouterState.of(context).uri.path;
    if (location.startsWith(Routes.contribution)) return 0;
    if (location.startsWith(Routes.trading)) return 1;
    if (location.startsWith(Routes.asset)) return 2;
    if (location.startsWith(Routes.profile)) return 3;
    return 0;
  }

  void _onItemTapped(int index, BuildContext context) {
    switch (index) {
      case 0:
        context.go(Routes.contribution);
        break;
      case 1:
        context.go(Routes.trading);
        break;
      case 2:
        context.go(Routes.asset);
        break;
      case 3:
        context.go(Routes.profile);
        break;
    }
  }
}