import 'package:flutter/material.dart';

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

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(title: 'My first app with flutter'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  int _time = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  void _startTime() {
    setState(() {
      _time = 0;
    });
    for (int i = 0; i < 20001; i++) {
      Future.delayed(Duration(milliseconds: i), () {
        if (_time == 20000) {
          _showFullScreenImage();
        } else {
          setState(() {
            _time = i;
          });
        }
      });
    }
  }

  void _showFullScreenImage() {
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (BuildContext context) {
        return Dialog(
          backgroundColor: Colors.transparent,
          insetPadding: EdgeInsets.zero,
          child: GestureDetector(
            onTap: () {
              Navigator.of(context).pop();
            },
            child: SizedBox.expand(
              child: Image.asset('assets/pict.png', fit: BoxFit.cover),
            ),
          ),
        );
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const SizedBox(height: 20),
            const Text(
              'Timer value:',
            ),
            Text(
              '$_time',
              style: Theme.of(context).textTheme.headlineMedium,
            ),
          ],
        ),
      ),
      floatingActionButton: Row(
        mainAxisAlignment: MainAxisAlignment.end,
        children: [
          const SizedBox(width: 10),
          FloatingActionButton(
            onPressed: _startTime,
            tooltip: 'Start Timer',
            child: const Icon(Icons.timer),
          ),
        ],
      ),
    );
  }
}