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

void main() {
  GoRouter.optionURLReflectsImperativeAPIs = true;
  runApp(const MyApp());
}

final GoRouter _router = GoRouter(
  routerNeglect: false,
  routes: <RouteBase>[
    GoRoute(
      path: '/',
      builder: (BuildContext context, GoRouterState state) {
        return const HomeScreen();
      },
      routes: <RouteBase>[
        GoRoute(
          name: 'page_1',
          path: 'page_1',
          builder: (BuildContext context, GoRouterState state) {
            return PageScreen1(pageKey: state.pageKey);
          },
        ),
        GoRoute(
          name: 'page_2',
          path: 'page_2',
          builder: (BuildContext context, GoRouterState state) {
            return const PageScreen2();
          },
        ),
      ],
    ),
  ],
);

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp.router(
      routerConfig: _router,
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Home Screen')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            ElevatedButton(
              onPressed: () async {
                GoRouter.of(context).push('/page_1');
              },
              child: const Text('Go to the page 1 screen'),
            ),
          ],
        ),
      ),
    );
  }
}

class PageScreen1 extends StatefulWidget {
  const PageScreen1({super.key, required this.pageKey});
  final ValueKey<String> pageKey;
  @override
  State<PageScreen1> createState() => _PageScreen1State();
}

class _PageScreen1State extends State<PageScreen1> {
  bool isLoaded = false;
  @override
  void initState() {
    super.initState();
    print('initState');
  }

  @override
  void didChangeDependencies() {
    Future<void>.delayed(const Duration(seconds: 2), () {
      setState(() {
        isLoaded = true;
      });
    });
    super.didChangeDependencies();
  }

  @override
  Widget build(BuildContext context) {
    return WillPopScope(
      onWillPop: () async => true,
      child: Scaffold(
        appBar: AppBar(title: const Text('Page Screen 1')),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              isLoaded
                  ? Text(
                      'Page key: ${widget.pageKey.toString()}',
                      style: const TextStyle(
                          fontSize: 20, fontWeight: FontWeight.bold),
                    )
                  : const CircularProgressIndicator(),
              const SizedBox(
                height: 40,
              ),
              ElevatedButton(
                onPressed: () {
                  GoRouter.of(context).pushNamed('page_2');
                },
                child: const Text('Go back Page 2 screen'),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class PageScreen2 extends StatelessWidget {
  const PageScreen2({super.key});

  @override
  Widget build(BuildContext context) {
    return WillPopScope(
      onWillPop: () async => true,
      child: Scaffold(
        appBar: AppBar(title: const Text('Page Screen 2')),
        body: const Center(child: Text('Page 2')),
      ),
    );
  }
}