// -*- mode:java; encoding:utf-8 -*-

// vim:set fileencoding=utf-8:

// https://ateraimemo.com/Swing/AnalogClock.html

//package example;

import java.awt.*;

import java.awt.geom.AffineTransform;

import java.awt.geom.Ellipse2D;

import java.awt.geom.Line2D;

import java.time.LocalTime;

import java.time.ZoneId;

import javax.swing.*;

public final class MainPanel extends JPanel {

  private MainPanel() {

    super(new BorderLayout());

    add(new AnalogClock());

    setPreferredSize(new Dimension(250, 250));

  }

  public static void main(String[] args) {

    EventQueue.invokeLater(MainPanel::createAndShowGui);

  }

  private static void createAndShowGui() {

    try {

      UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());

    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {

      ex.printStackTrace();

      Toolkit.getDefaultToolkit().beep();

    }

    JFrame frame = new JFrame("AnalogClock");

    frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    frame.getContentPane().add(new MainPanel());

    frame.pack();

    frame.setLocationRelativeTo(null);

    frame.setVisible(true);

  }

}

class AnalogClock extends JPanel {

  protected LocalTime time;// = LocalTime.now(ZoneId.systemDefault());

  protected AnalogClock() {

    super();

    new Timer(100, e -> {

      time = LocalTime.now(ZoneId.systemDefault());

      repaint();

    }).start();

  }

  @Override protected void paintComponent(Graphics g) {

    Graphics2D g2 = (Graphics2D) g.create();

    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

    Rectangle rect = SwingUtilities.calculateInnerArea(this, null);

    g2.setColor(Color.BLACK);

    g2.fill(rect);

    float radius = Math.min(rect.width, rect.height) / 2f - 10f;

    // g2.fill(new Ellipse2D.Double(rect.getCenterX() - radius, rect.getCenterY() - radius, radius * 2f, radius * 2f));

    g2.translate(rect.getCenterX(), rect.getCenterY());

    // Drawing the hour markers

    float hourMarkerLen = radius / 6f - 10f;

    Shape hourMarker = new Line2D.Float(0f, hourMarkerLen - radius, 0f, -radius);