import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flux/core/blocs/session/session_bloc.dart';
import 'package:flux/core/theme/theme.dart';
import 'package:flux/features/master_data/master_data_hub_content.dart';
import 'package:flux/features/services/blocs/services_cubit.dart';
import 'package:flux/features/services/ui/services_screen.dart';
import 'dashboard_content.dart'; // Importiamo il contenuto della dashboard

class HomeScreen extends StatefulWidget {
  const HomeScreen({super.key});

  @override
  State<HomeScreen> createState() => _HomeScreenState();
}

class _HomeScreenState extends State<HomeScreen> {
  int _selectedIndex = 0;
  bool _extendRailway = false;

  @override
  void initState() {
    super.initState();
    // Caricamento "silenzioso" all'avvio dell'app
    // Usiamo WidgetsBinding per assicurarci che il contesto sia pronto
    WidgetsBinding.instance.addPostFrameCallback((_) {
      context.read<ServicesCubit>().loadServices();
    });
  }

  @override
  Widget build(BuildContext context) {
    return BlocBuilder<SessionBloc, SessionState>(
      builder: (context, state) {
        return LayoutBuilder(
          builder: (context, constraints) {
            // Se lo schermo è più largo di 900px usiamo il layout Desktop
            final bool isLargeScreen = constraints.maxWidth > 900;

            return Scaffold(
              body: Row(
                children: [
                  // --- SIDEBAR (Desktop) ---
                  if (isLargeScreen)
                    _buildNavigationRail(constraints.maxWidth > 1200),

                  // --- CONTENUTO DINAMICO ---
                  Expanded(
                    child: _buildPageContent(_selectedIndex, isLargeScreen),
                  ),
                ],
              ),
              // --- BOTTOM BAR (Solo Mobile) ---
              bottomNavigationBar: isLargeScreen
                  ? null
                  : _buildBottomNavigationBar(_selectedIndex),
            );
          },
        );
      },
    );
  }

  // --- BOTTOM NAVIGATION BAR (Mobile) ---
  Widget _buildBottomNavigationBar(int selectedIndex) {
    return BottomNavigationBar(
      currentIndex: selectedIndex,
      onTap: (index) => setState(() => _selectedIndex = index),
      selectedItemColor: context.accent,
      unselectedItemColor: context.secondaryText,
      items: const [
        BottomNavigationBarItem(
          icon: Icon(Icons.dashboard),
          label: 'Dashboard',
        ),
        BottomNavigationBarItem(
          icon: Icon(Icons.receipt_long),
          label: 'Servizi',
        ),
        BottomNavigationBarItem(
          icon: Icon(Icons.folder_shared),
          label: 'Anagrafiche',
        ),
      ],
    );
  }

  // --- NAVIGATION RAIL (Desktop) ---
  Widget _buildNavigationRail(bool veryLargeScreen) {
    return MouseRegion(
      onEnter: (_) => setState(() => _extendRailway = true),
      onExit: (_) => setState(() => _extendRailway = false),
      child: NavigationRail(
        // Manteniamo 'extended' dinamico in base alla larghezza per un look Pro
        extended: veryLargeScreen ? true : _extendRailway,
        selectedIndex: _selectedIndex,
        onDestinationSelected: (index) =>
            setState(() => _selectedIndex = index),
        backgroundColor: context.background,
        indicatorColor: context.accent.withValues(alpha: 0.2),

        // Header con il logo FLUX o l'icona bolt
        leading: _buildRailHeader(veryLargeScreen),

        selectedIconTheme: IconThemeData(color: context.accent, size: 28),
        unselectedIconTheme: IconThemeData(
          color: context.secondaryText,
          size: 24,
        ),

        selectedLabelTextStyle: TextStyle(
          color: context.accent,
          fontWeight: FontWeight.bold,
        ),
        unselectedLabelTextStyle: TextStyle(color: context.secondaryText),

        destinations: const [
          NavigationRailDestination(
            icon: Icon(Icons.dashboard_outlined),
            selectedIcon: Icon(Icons.dashboard),
            label: Text('Dashboard'),
          ),
          NavigationRailDestination(
            icon: Icon(Icons.receipt_long_outlined),
            selectedIcon: Icon(Icons.receipt_long),
            label: Text('Servizi'),
          ),
          NavigationRailDestination(
            icon: Icon(Icons.folder_shared_outlined),
            selectedIcon: Icon(Icons.folder_shared),
            label: Text(
              'Anagrafiche',
            ), // Questo caricherà il MasterDataHubContent
          ),
        ],
      ),
    );
  }

  Widget _buildRailHeader(bool veryLargeScreen) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 24),
      child: GestureDetector(
        onTap: veryLargeScreen
            ? null
            : () => setState(() => _extendRailway = !_extendRailway),
        child: _extendRailway
            ? Text(
                'FLUX',
                style: TextStyle(
                  fontWeight: FontWeight.bold,
                  fontSize: 24,
                  color: context.accent,
                ),
              )
            : Icon(Icons.bolt, color: context.accent, size: 32),
      ),
    );
  }

  // Switch tra le sottopagine
  Widget _buildPageContent(int index, bool isLargeScreen) {
    return IndexedStack(
      index: index,
      children: [
        DashboardContent(
          isLargeScreen: isLargeScreen,
          onTabRequested: (idx) => setState(() => _selectedIndex = 2),
        ),

        ServicesScreen(),

        // L'unico punto di ingresso per tutte le anagrafiche
        MasterDataHubContent(
          // Qui gestiamo la navigazione "interna" all'hub
          onOpenPage: (widget) {
            Navigator.push(
              context,
              MaterialPageRoute(builder: (context) => widget),
            );
          },
        ),
      ],
    );
  }
}