import 'dart:async';

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

class AppScrollBehavior extends MaterialScrollBehavior {
  const AppScrollBehavior();

  @override
  Set<PointerDeviceKind> get dragDevices => const {...PointerDeviceKind.values};
}

void main() {
  runApp(const MainApp());
}

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        appBarTheme: const AppBarTheme(centerTitle: true),
        pageTransitionsTheme: PageTransitionsTheme(
          builders: {
            for (final platform in TargetPlatform.values)
              platform: const CupertinoPageTransitionsBuilder(),
          },
        ),
      ),
      scrollBehavior: const AppScrollBehavior(),
      home: const ScreenOne(),
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Screen One'),
      ),
      body: Center(
        child: TextButton(
          onPressed: () {
            Navigator.of(context).push(
              MaterialPageRoute(builder: (_) => const ScreenTwo()),
            );
          },
          child: const Text('Go to Screen Two'),
        ),
      ),
    );
  }
}

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

  @override
  State<ScreenTwo> createState() => _ScreenTwoState();
}

class _ScreenTwoState extends State<ScreenTwo> {
  int seconds = 5;
  late Timer timer;

  @override
  void initState() {
    super.initState();

    timer = Timer.periodic(
      const Duration(seconds: 1),
      (Timer timer) {
        setState(() => seconds--);

        if (seconds == 0) {
          timer.cancel();
          pop();
        }
      },
    );
  }

  @override
  void dispose() {
    timer.cancel();
    super.dispose();
  }

  void pop() {
    Navigator.of(context).pop();
  }

  void maybePop() {
    Navigator.of(context).maybePop();
  }

  void navigate() {
    Navigator.of(context).push(
      MaterialPageRoute(builder: (_) => const ScreenThree()),
    );
  }

  @override
  Widget build(BuildContext context) {
    return PopScope(
      canPop: true,
      onPopInvoked: (didPop) => print('ScreenTwo onPopInvoked didPop? $didPop'),
      child: Scaffold(
        appBar: AppBar(
          title: const Text('Screen Two'),
        ),
        body: Center(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              Text('Auto pop in: $seconds'),
              const SizedBox(height: 8),
              TextButton(
                onPressed: pop,
                child: const Text('Pop'),
              ),
              const SizedBox(height: 8),
              TextButton(
                onPressed: maybePop,
                child: const Text('Maybe Pop'),
              ),
              const SizedBox(height: 8),
              TextButton(
                onPressed: navigate,
                child: const Text('Go to Screen Three'),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return PopScope(
      canPop: true,
      onPopInvoked: (didPop) =>
          print('ScreenThree onPopInvoked didPop? $didPop'),
      child: Scaffold(
        appBar: AppBar(
          title: const Text('Screen Three'),
        ),
        body: const Center(
          child: Text('Hello World!'),
        ),
      ),
    );
  }
}