import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';

class AppShell extends StatelessWidget {
  final Widget child;

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

  // Calcoliamo l'indice attivo in base all'URL corrente!
  int _calculateSelectedIndex(BuildContext context) {
    final String location = GoRouterState.of(context).uri.path;
    if (location.startsWith('/master-data')) return 1;
    if (location.startsWith('/settings')) return 2;
    return 0; // Default: Dashboard
  }

  void _onItemTapped(int index, BuildContext context) {
    switch (index) {
      case 0:
        context.go('/');
        break;
      case 1:
        context.go('/master-data');
        break;
      case 2:
        context.go('/settings');
        break;
    }
  }

  @override
  Widget build(BuildContext context) {
    final currentIndex = _calculateSelectedIndex(context);
    // Breakpoint: se lo schermo è più largo di 600px, usiamo la Rail laterale
    final isDesktop = MediaQuery.sizeOf(context).width >= 600;

    return Scaffold(
      body: isDesktop
          ? Row(
              children: [
                NavigationRail(
                  selectedIndex: currentIndex,
                  onDestinationSelected: (index) =>
                      _onItemTapped(index, context),
                  labelType: NavigationRailLabelType.all,
                  destinations: const [
                    NavigationRailDestination(
                      icon: Icon(Icons.dashboard_outlined),
                      selectedIcon: Icon(Icons.dashboard),
                      label: Text('Dashboard'),
                    ),
                    NavigationRailDestination(
                      icon: Icon(Icons.folder_special_outlined),
                      selectedIcon: Icon(Icons.folder_special),
                      label: Text('Anagrafiche'),
                    ),
                    NavigationRailDestination(
                      icon: Icon(Icons.settings_outlined),
                      selectedIcon: Icon(Icons.settings),
                      label: Text('Impostazioni'),
                    ),
                  ],
                ),
                const VerticalDivider(thickness: 1, width: 1),
                // Il contenuto della pagina
                Expanded(child: child),
              ],
            )
          : child, // Su mobile il contenuto prende tutto lo schermo...
      // ... e mettiamo la barra in basso!
      bottomNavigationBar: isDesktop
          ? null
          : NavigationBar(
              selectedIndex: currentIndex,
              onDestinationSelected: (index) => _onItemTapped(index, context),
              destinations: const [
                NavigationDestination(
                  icon: Icon(Icons.dashboard_outlined),
                  selectedIcon: Icon(Icons.dashboard),
                  label: 'Dashboard',
                ),
                NavigationDestination(
                  icon: Icon(Icons.folder_special_outlined),
                  selectedIcon: Icon(Icons.folder_special),
                  label: 'Anagrafiche',
                ),
                NavigationDestination(
                  icon: Icon(Icons.settings_outlined),
                  selectedIcon: Icon(Icons.settings),
                  label: 'Impostazioni',
                ),
              ],
            ),
    );
  }
}