import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../../core/theme/app_colors.dart';
import 'package:go_router/go_router.dart';
import 'package:tdesign_flutter/tdesign_flutter.dart';
import '../../core/i18n/app_localizations.dart';
import '../../core/theme/app_colors_extension.dart';
import 'nav_bar_config.dart';

/// 应用级 Scaffold：NavBar + body + 可选 BottomTabBar
class AppScaffold extends ConsumerWidget {
  final Widget body;
  final bool showTabBar;
  final bool resizeToAvoidBottomInset;
  final NavBarConfig? navConfig;

  const AppScaffold({
    super.key,
    required this.body,
    this.showTabBar = false,
    this.resizeToAvoidBottomInset = true,
    this.navConfig,
  });

  bool _isRootTab(String location) {
    final path = location.split('?').first;
    return path == '/' || path == '/messages' || path == '/profile';
  }

  String? _titleForRoute(String location, AppLocalizations l10n) {
    final path = location.split('?').first;
    if (path == '/') {
      return l10n.get('appName');
    }
    if (path == '/messages') {
      return l10n.get('tabMessages');
    }
    if (path == '/profile') {
      return l10n.get('tabProfile');
    }
    if (path.startsWith('/expense/list')) {
      return l10n.get('expenseList');
    }
    if (path.startsWith('/expense/import-apply')) {
      return l10n.get('importExpenseApply');
    }
    if (path.startsWith('/expense/detail')) {
      return l10n.get('expenseDetail');
    }
    if (path.startsWith('/expense/edit')) {
      return l10n.get('editExpense');
    }
    if (path.startsWith('/expense/create')) {
      return l10n.get('expenseApply');
    }
    if (path.startsWith('/expense-apply/list')) {
      return l10n.get('expenseApplyList');
    }
    if (path.startsWith('/expense-apply/detail')) {
      return l10n.get('expenseApplyDetail');
    }
    if (path.startsWith('/expense-apply/edit')) {
      return l10n.get('editApply');
    }
    if (path.startsWith('/expense-apply/create')) {
      return l10n.get('expenseApplyRequest');
    }
    if (path.startsWith('/overtime-apply/list')) {
      return l10n.get('overtimeList');
    }
    if (path.startsWith('/overtime-apply/detail')) {
      return l10n.get('overtimeDetail');
    }
    if (path.startsWith('/overtime-apply/create')) {
      return l10n.get('overtimeRequest');
    }
    if (path.startsWith('/overtime-apply/edit')) {
      return l10n.get('editOvertime');
    }
    if (path.startsWith('/vehicle-apply/list')) {
      return l10n.get('vehicleList');
    }
    if (path.startsWith('/vehicle-apply/detail')) {
      return l10n.get('vehicleDetail');
    }
    if (path.startsWith('/vehicle-apply/create')) {
      return l10n.get('vehicleRequest');
    }
    if (path.startsWith('/vehicle-apply/edit')) {
      return l10n.get('editVehicle');
    }
    if (path.startsWith('/outing-log/list')) {
      return l10n.get('outingLogList');
    }
    if (path.startsWith('/outing-log/detail')) {
      return l10n.get('outingLogDetail');
    }
    if (path.startsWith('/outing-log/create')) {
      return l10n.get('outingLogCreate');
    }
    if (path.startsWith('/announcement/list')) {
      return l10n.get('announcementList');
    }
    if (path.startsWith('/announcement/detail')) {
      return l10n.get('announcementDetail');
    }
    if (path.startsWith('/announcement/create')) {
      return l10n.get('announcementCreate');
    }
    if (path.startsWith('/report/expense-detail')) {
      return l10n.get('reportExpenseDetail');
    }
    if (path.startsWith('/report/expense-apply-detail')) {
      return l10n.get('reportExpenseApplyDetail');
    }
    if (path.startsWith('/report/overtime-apply')) {
      return l10n.get('reportOvertimeDetail');
    }
    if (path.startsWith('/report/vehicle-apply')) {
      return l10n.get('reportVehicleDetail');
    }
    if (path.startsWith('/report/outing-log')) {
      return l10n.get('reportOutingLogDetail');
    }
    if (path.startsWith('/admin/permissions')) {
      return l10n.get('permissionManagement');
    }
    return null;
  }

  NavBarConfig _rootConfig(String location, AppLocalizations l10n) {
    final path = location.split('?').first;
    if (path == '/messages') {
      return NavBarConfig(
        title: l10n.get('tabMessages'),
        showBack: true,
        leadingIcon: Icons.close,
      );
    }
    if (path == '/') {
      return NavBarConfig(
        title: l10n.get('appName'),
        showBack: true,
        leadingIcon: Icons.close,
      );
    }
    if (path == '/profile') {
      return NavBarConfig(
        title: l10n.get('tabProfile'),
        showBack: true,
        leadingIcon: Icons.close,
      );
    }
    return NavBarConfig.home;
  }

  NavBarConfig _resolve(
    NavBarConfig cfg,
    String location,
    AppLocalizations l10n,
  ) {
    final routeTitle = _titleForRoute(location, l10n);
    if (routeTitle == null) return cfg;
    return NavBarConfig(
      title: routeTitle,
      showBack: cfg.showBack,
      showRight: cfg.showRight,
      rightWidget: cfg.rightWidget,
      onBack: cfg.onBack,
      leadingIcon: cfg.leadingIcon,
    );
  }

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    SystemChrome.setSystemUIOverlayStyle(
      const SystemUiOverlayStyle(
        statusBarColor: Colors.transparent,
        statusBarIconBrightness: Brightness.dark,
      ),
    );
    final colors = Theme.of(context).extension<AppColorsExtension>()!;
    final l10n = AppLocalizations.of(context);
    final location = GoRouterState.of(context).uri.toString();
    final config = navConfig != null
        ? _resolve(navConfig!, location, l10n)
        : _rootConfig(location, l10n);
    // 页面可通过 pageBackProvider 覆盖返回按钮行为（如 create 页面的 _doPop）
    final pageBack = ref.watch(pageBackProvider);

    return Scaffold(
      resizeToAvoidBottomInset: resizeToAvoidBottomInset,
      backgroundColor: colors.bgPage,
      body: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          _NavBarView(
            config: config,
            location: location,
            pageBack: pageBack,
            onBack: () {
              if (_isRootTab(location)) {
                SystemNavigator.pop();
              } else {
                final router = GoRouter.of(context);
                if (router.canPop()) {
                  router.pop();
                } else {
                  SystemNavigator.pop();
                }
              }
            },
          ),
          Expanded(child: body),
          if (showTabBar)
            Container(
              color: colors.bgCard,
              child: _AppTabBar(location: location),
            ),
        ],
      ),
    );
  }
}

class _NavBarView extends StatelessWidget {
  final NavBarConfig config;
  final String location;
  final VoidCallback? pageBack;
  final VoidCallback onBack;
  const _NavBarView({
    required this.config,
    required this.location,
    this.pageBack,
    required this.onBack,
  });

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).extension<AppColorsExtension>()!;
    List<TDNavBarItem>? leftItems;
    if (config.showBack) {
      final icon = config.leadingIcon ?? TDIcons.chevron_left;
      // config.onBack（路由级声明）优先于 pageBack（页面级 Provider），
      // 防止 Provider 残留值泄漏到不相关的页面
      final backAction = config.onBack ?? pageBack ?? onBack;
      leftItems = [
        TDNavBarItem(
          icon: icon,
          iconSize: 22,
          iconColor: colors.textPrimary,
          action: backAction,
        ),
      ];
    }
    List<TDNavBarItem>? rightItems;
    if (config.showRight && config.rightWidget != null) {
      rightItems = [TDNavBarItem(iconWidget: config.rightWidget, iconSize: 22)];
    }
    return TDNavBar(
      title: config.title,
      titleColor: colors.textPrimary,
      titleFontWeight: FontWeight.w600,
      titleFont: Font(size: AppFontSizes.title.toInt(), lineHeight: 26),
      backgroundColor: colors.bgCard,
      height: 56,
      centerTitle: true,
      useDefaultBack: false,
      screenAdaptation: true,
      leftBarItems: leftItems,
      rightBarItems: rightItems,
    );
  }
}

class _AppTabBar extends StatelessWidget {
  final String location;
  const _AppTabBar({required this.location});

  static int tabIndex(String location) {
    if (location.startsWith('/messages')) {
      return 0;
    }
    if (location == '/' ||
        (!location.startsWith('/messages') &&
            !location.startsWith('/profile'))) {
      return 1;
    }
    return 2;
  }

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).extension<AppColorsExtension>()!;
    final l10n = AppLocalizations.of(context);
    return LayoutBuilder(
      builder: (ctx, constraints) {
        if (constraints.maxWidth <= 0) return const SizedBox.shrink();
        final bottomPadding = MediaQuery.of(ctx).padding.bottom;
        return Padding(
          padding: EdgeInsets.only(top: 0, bottom: 8 + bottomPadding),
          child: TDBottomTabBar(
            TDBottomTabBarBasicType.iconText,
            useSafeArea: false,
            componentType: TDBottomTabBarComponentType.label,
            outlineType: TDBottomTabBarOutlineType.filled,
            backgroundColor: colors.bgCard,
            dividerColor: Colors.transparent,
            selectedBgColor: colors.primaryLight,
            unselectedBgColor: Colors.transparent,
            currentIndex: tabIndex(location),
            navigationTabs: [
              TDBottomTabBarTabConfig(
                tabText: l10n.get('tabMessages'),
                selectedIcon: Icon(
                  Icons.notifications,
                  size: 22,
                  color: colors.primary,
                ),
                unselectedIcon: Icon(
                  Icons.notifications_outlined,
                  size: 22,
                  color: colors.textSecondary,
                ),
                selectTabTextStyle: TextStyle(
                  fontSize: 10,
                  fontWeight: FontWeight.w600,
                  color: colors.primary,
                ),
                unselectTabTextStyle: TextStyle(
                  fontSize: 10,
                  color: colors.textSecondary,
                ),
                onTap: () => context.go('/messages'),
              ),
              TDBottomTabBarTabConfig(
                tabText: l10n.get('tabWorkbench'),
                selectedIcon: Icon(
                  Icons.dashboard,
                  size: 22,
                  color: colors.primary,
                ),
                unselectedIcon: Icon(
                  Icons.dashboard_outlined,
                  size: 22,
                  color: colors.textSecondary,
                ),
                selectTabTextStyle: TextStyle(
                  fontSize: 10,
                  fontWeight: FontWeight.w600,
                  color: colors.primary,
                ),
                unselectTabTextStyle: TextStyle(
                  fontSize: 10,
                  color: colors.textSecondary,
                ),
                onTap: () => context.go('/'),
              ),
              TDBottomTabBarTabConfig(
                tabText: l10n.get('tabProfile'),
                selectedIcon: Icon(
                  Icons.person,
                  size: 22,
                  color: colors.primary,
                ),
                unselectedIcon: Icon(
                  Icons.person_outline,
                  size: 22,
                  color: colors.textSecondary,
                ),
                selectTabTextStyle: TextStyle(
                  fontSize: 10,
                  fontWeight: FontWeight.w600,
                  color: colors.primary,
                ),
                unselectTabTextStyle: TextStyle(
                  fontSize: 10,
                  color: colors.textSecondary,
                ),
                onTap: () => context.go('/profile'),
              ),
            ],
          ),
        );
      },
    );
  }
}