import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import '../../core/network/api_client.dart';
import '../../core/network/signalr_service.dart';
import '../../core/theme/app_theme.dart';
import '../../core/theme/theme_cubit.dart';
import '../../features/admin/views/admin_evaluation_history_screen.dart';
import '../../features/admin/views/admin_users_screen.dart';
import '../../features/auth/models/user_model.dart';
import '../../features/bot/views/bot_control_panel_screen.dart';
import '../../features/calendar/views/corporate_calendar_screen.dart';
import '../../features/dashboard/views/dashboard_screen.dart';
import '../../features/discovery/cubit/discovery_cubit.dart';
import '../../features/favorites/cubit/favorites_cubit.dart';

import '../../features/favorites/views/favorites_screen.dart';
import '../../features/news/views/news_feed_screen.dart';
import '../../features/simulation/views/backtest_visualizer_screen.dart';
import '../../features/trades/views/trades_feed_screen.dart';
import 'global_app_bar.dart';

/// Main Responsive Shell consuming root FavoritesCubit and ThemeCubit state.
class ResponsiveScaffold extends StatefulWidget {
  final UserModel user;
  final ApiClient apiClient;
  final SignalRService signalRService;

  const ResponsiveScaffold({
    super.key,
    required this.user,
    required this.apiClient,
    required this.signalRService,
  });

  @override
  State<ResponsiveScaffold> createState() => _ResponsiveScaffoldState();
}

class _ResponsiveScaffoldState extends State<ResponsiveScaffold> {
  int _selectedIndex = 0;

  @override
  void initState() {
    super.initState();
    // Load favorites immediately after auth is confirmed and widget is mounted.
    // Using addPostFrameCallback ensures the BlocProvider tree is fully built.
    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (mounted) {
        context.read<FavoritesCubit>().loadFavorites();
        context.read<DiscoveryCubit>().loadDiscovery();
      }
    });

  }

  List<String> get _tabTitles => [
        'Dashboard',
        'News Feed',
        'Favoriten',
        'Kalender',
        'Live Trades',
        if (widget.user.isAdmin) 'Bot Panel',
        if (widget.user.isAdmin) 'Backtest',
        if (widget.user.isAdmin) 'Admin Panel',
        if (widget.user.isAdmin) 'Evaluierungs-Historie',
      ];

  @override
  Widget build(BuildContext context) {
    final bool isDesktop = MediaQuery.of(context).size.width >= 800;
    final titles = _tabTitles;
    final activeTitle = _selectedIndex < titles.length ? titles[_selectedIndex] : 'Dashboard';

    final List<Widget> pages = [
      DashboardScreen(apiClient: widget.apiClient, signalRService: widget.signalRService),
      NewsFeedScreen(apiClient: widget.apiClient),
      FavoritesScreen(apiClient: widget.apiClient),
      CorporateCalendarScreen(apiClient: widget.apiClient),
      TradesFeedScreen(apiClient: widget.apiClient, signalRService: widget.signalRService),
      if (widget.user.isAdmin) BotControlPanelScreen(apiClient: widget.apiClient, signalRService: widget.signalRService),
      if (widget.user.isAdmin) BacktestVisualizerScreen(apiClient: widget.apiClient),
      if (widget.user.isAdmin) AdminUsersScreen(apiClient: widget.apiClient, signalRService: widget.signalRService),
      if (widget.user.isAdmin) AdminEvaluationHistoryScreen(apiClient: widget.apiClient),
    ];

    return BlocBuilder<ThemeCubit, ThemeState>(
      builder: (context, themeState) {
        final activeTheme = themeState.preset;

        return Scaffold(
          backgroundColor: activeTheme.darkBackground,
          appBar: GlobalAppBar(
            user: widget.user,
            apiClient: widget.apiClient,
            signalRService: widget.signalRService,
            currentTabTitle: activeTitle,
          ),
          body: isDesktop
              ? Row(
                  children: [
                    _DesktopSidebar(
                      selectedIndex: _selectedIndex,
                      isAdmin: widget.user.isAdmin,
                      onDestinationSelected: (idx) => setState(() => _selectedIndex = idx),
                    ),
                    VerticalDivider(width: 1, color: activeTheme.glassBorder),
                    Expanded(
                      child: AnimatedSwitcher(
                        duration: const Duration(milliseconds: 200),
                        child: pages[_selectedIndex],
                      ),
                    ),
                  ],
                )
              : AnimatedSwitcher(
                  duration: const Duration(milliseconds: 200),
                  child: pages[_selectedIndex],
                ),
          bottomNavigationBar: isDesktop
              ? null
              : BottomNavigationBar(
                  currentIndex: _selectedIndex,
                  onTap: (idx) => setState(() => _selectedIndex = idx),
                  backgroundColor: activeTheme.cardSurface,
                  selectedItemColor: activeTheme.primaryColor,
                  unselectedItemColor: activeTheme.textMuted,
                  type: BottomNavigationBarType.fixed,
                  items: [
                    const BottomNavigationBarItem(icon: Icon(Icons.dashboard_rounded), label: 'Dashboard'),
                    const BottomNavigationBarItem(icon: Icon(Icons.newspaper_rounded), label: 'News'),
                    const BottomNavigationBarItem(icon: Icon(Icons.star_rounded), label: 'Favoriten'),
                    const BottomNavigationBarItem(icon: Icon(Icons.calendar_month_rounded), label: 'Kalender'),
                    const BottomNavigationBarItem(icon: Icon(Icons.candlestick_chart_rounded), label: 'Trades'),
                    if (widget.user.isAdmin)
                      const BottomNavigationBarItem(icon: Icon(Icons.smart_toy_outlined), label: 'Bot'),
                    if (widget.user.isAdmin)
                      const BottomNavigationBarItem(icon: Icon(Icons.query_stats_rounded), label: 'Backtest'),
                    if (widget.user.isAdmin)
                      const BottomNavigationBarItem(icon: Icon(Icons.admin_panel_settings_outlined), label: 'Admin'),
                    if (widget.user.isAdmin)
                      const BottomNavigationBarItem(icon: Icon(Icons.history_rounded), label: 'Historie'),
                  ],
                ),
        );
      },
    );
  }
}

class _DesktopSidebar extends StatelessWidget {
  final int selectedIndex;
  final bool isAdmin;
  final ValueChanged<int> onDestinationSelected;

  const _DesktopSidebar({
    required this.selectedIndex,
    required this.isAdmin,
    required this.onDestinationSelected,
  });

  @override
  Widget build(BuildContext context) {
    final activeTheme = AppTheme.activePreset;

    return Container(
      width: 220,
      color: activeTheme.cardSurface,
      child: ListView(
        padding: const EdgeInsets.symmetric(vertical: 12),
        children: [
          _navTile(activeTheme, 0, Icons.dashboard_rounded, 'Dashboard'),
          _navTile(activeTheme, 1, Icons.newspaper_rounded, 'News Feed'),
          _navTile(activeTheme, 2, Icons.star_rounded, 'Favoriten'),
          _navTile(activeTheme, 3, Icons.calendar_month_rounded, 'Kalender'),
          _navTile(activeTheme, 4, Icons.candlestick_chart_rounded, 'Live Trades'),
          if (isAdmin) _navTile(activeTheme, 5, Icons.smart_toy_outlined, 'Bot Panel'),
          if (isAdmin) _navTile(activeTheme, 6, Icons.query_stats_rounded, 'Backtest'),
          if (isAdmin) _navTile(activeTheme, 7, Icons.admin_panel_settings_outlined, 'Admin Panel'),
          if (isAdmin) _navTile(activeTheme, 8, Icons.history_rounded, 'Evaluierungs-Historie'),
        ],
      ),
    );
  }

  Widget _navTile(ThemePreset activeTheme, int index, IconData icon, String label) {
    final isSelected = selectedIndex == index;
    return Container(
      margin: const EdgeInsets.symmetric(horizontal: 12, vertical: 3),
      child: ListTile(
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(activeTheme.borderRadius * 0.7)),
        selected: isSelected,
        selectedTileColor: activeTheme.primaryColor.withValues(alpha: 0.15),
        leading: Icon(icon, color: isSelected ? activeTheme.primaryColor : activeTheme.textSecondary, size: 20),
        title: Text(
          label,
          style: TextStyle(
            color: isSelected ? activeTheme.primaryColor : activeTheme.textSecondary,
            fontWeight: isSelected ? FontWeight.bold : FontWeight.normal,
            fontSize: 13,
          ),
        ),
        onTap: () => onDestinationSelected(index),
      ),
    );
  }
}