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: .fromSeed(seedColor: Colors.deepPurple),
      ),
      showPerformanceOverlay: true, // Enables the performance overlay
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

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

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  static const double _minRadius = 1;
  static const double _maxRadius = 500;
  static const double _defaultRadius = 150;

  double _turns = 0;
  double _radius = _defaultRadius;
  final _controller = TextEditingController(text: '$_defaultRadius');

  void _turn() {
    setState(() {
      _turns += 5;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: .center,
          children: [
            AnimatedRotation(
              turns: _turns,
              duration: Duration(seconds: 10),
              child: CustomPaint(
                foregroundPainter: _MyCirclePainter(rows: 50, cols: 50, radius: _radius),
                size: Size(400, 400),
              ),
            )
          ],
        ),
      ),
      bottomNavigationBar: BottomAppBar(
        child: Row(
          mainAxisAlignment: .center,
          children: <Widget>[
            ElevatedButton(onPressed: _turn, child: Text('Turn')),
            SizedBox(width: 20),
            Text('Radius'),
            Slider(
              value: _radius,
              min: _minRadius,
              max: _maxRadius,
              onChanged: (value) {
                setState(() {
                  _radius = value;
                  _controller.text = _radius.toStringAsFixed(1);
                });
              },
            ),
            SizedBox(
              width: 100,
              child: TextField(
                controller: _controller,
                keyboardType: .number,
                onSubmitted: (newString) {
                  double? newValue = double.tryParse(newString);
                  if (newValue != null) {
                    setState(() {
                      _radius = newValue.clamp(_minRadius, _maxRadius);
                    });
                  }
                },
                decoration: InputDecoration(
                  filled: true,
                  fillColor: Colors.white,
                  border: OutlineInputBorder(),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _MyCirclePainter extends CustomPainter {
  static final List<Color> colors = <Color>[
    Colors.purple,
    Colors.blue,
    Colors.green,
    Colors.yellow,
    Colors.orange,
    Colors.red,
  ];

  _MyCirclePainter({required this.rows, required this.cols, required this.radius});

  final int rows;
  final int cols;
  final double radius;

  @override
  void paint(Canvas canvas, Size size) {
    Paint paint = Paint()
        ..style = PaintingStyle.fill;
    paint.color = Colors.white;
    canvas.drawRect(Offset.zero & size, paint);
    Size gridSize = Size(2 * radius * cols, 2 * radius * rows);
    Size gridSpace = Size(
      size.width - gridSize.width,
      size.height - gridSize.height,
    );
    Size cellPadding = Size(
      gridSpace.width / (cols + 1),
      gridSpace.height / (rows + 1),
    );
    canvas.translate(cellPadding.width + radius, cellPadding.height + radius);

    int colorIndex = 0;
    for (int y = 0; y < rows; y++) {
      double circleY = (cellPadding.height + radius * 2) * y;
      for (int x = 0; x < cols; x++) {
        double circleX = (cellPadding.width + radius * 2) * x;
        paint.color = colors[colorIndex++ % colors.length];
        canvas.drawCircle(Offset(circleX, circleY), radius, paint);
      }
    }
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) => true;
}