import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'providers/app_provider.dart';
import 'pages/settings/settings_page.dart';
import 'pages/home/home_page.dart';
import 'pages/search/search_page.dart';
import 'pages/carts/cart_list_page.dart';

class TikuApp extends ConsumerStatefulWidget {
  const TikuApp({super.key});

  @override
  ConsumerState<TikuApp> createState() => _TikuAppState();
}

class _TikuAppState extends ConsumerState<TikuApp> {
  @override
  void initState() {
    super.initState();
    Future.microtask(() => ref.read(connectionProvider.notifier).initialize());
  }

  @override
  Widget build(BuildContext context) {
    final connState = ref.watch(connectionProvider);

    return MaterialApp(
      title: '某人的题库',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        colorSchemeSeed: Colors.blue,
        useMaterial3: true,
        brightness: Brightness.light,
        appBarTheme: const AppBarTheme(centerTitle: true),
      ),
      home: connState.status == ConnectionStatus.configured
          ? const MainShell()
          : const SettingsPage(),
    );
  }
}

/// 主界面 Shell — 底部标签导航
class MainShell extends ConsumerStatefulWidget {
  const MainShell({super.key});

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

class _MainShellState extends ConsumerState<MainShell> {
  int _currentIndex = 0;

  final _pages = const [
    HomePage(),
    SearchPage(),
    CartListPage(),
    SettingsPage(),
  ];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: IndexedStack(index: _currentIndex, children: _pages),
      bottomNavigationBar: NavigationBar(
        selectedIndex: _currentIndex,
        onDestinationSelected: (i) => setState(() => _currentIndex = i),
        destinations: const [
          NavigationDestination(icon: Icon(Icons.library_books), label: '题库'),
          NavigationDestination(icon: Icon(Icons.search), label: '搜索'),
          NavigationDestination(icon: Icon(Icons.shopping_cart), label: '试题篮'),
          NavigationDestination(icon: Icon(Icons.settings), label: '设置'),
        ],
      ),
    );
  }
}