import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.ArrayList;
import javax.swing.*;

class Draw extends JFrame implements ActionListener, ItemListener {

  static final ArrayList<MyShape> shapes = new ArrayList<>();

  // Initial Frame size
  static final int FWIDTH = 600;  // frame width
  static final int FHEIGHT = 450; // frame height

  // Color choices
  static final String COLOR_NAMES[] = {"None", "Red", "Blue", "Green"};
  static final Color COLORS[] = {null, Color.red, Color.blue, Color.green};

  // Button control
  JButton circle;
  JButton roundRec;
  JButton threeDRec;

  // Color choice box
  JComboBox<String> colorChoice;
  JList<String> jList1;
  JScrollPane jScrollPane2;

  // the canvas
  DrawCanvas canvas;

  /**
   * Constructor
   */
public
  Draw() {
    super("Java Draw");
    setLayout(new BorderLayout());

    // create panel for controls
    JPanel topPanel = new JPanel(new GridLayout(2, 1));
    add(topPanel, BorderLayout.NORTH);

    // create button control
    JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
    topPanel.add(buttonPanel);

    circle = new JButton("Circle");
    buttonPanel.add(circle);
    roundRec = new JButton("Rounded Rectangle");
    buttonPanel.add(roundRec);
    threeDRec = new JButton("3D Rectangle");
    buttonPanel.add(threeDRec);

    // add button listener
    circle.addActionListener(this);
    roundRec.addActionListener(this);
    threeDRec.addActionListener(this);

    // create panel for color choices
    JPanel colorPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
    topPanel.add(colorPanel);
    JLabel label = new JLabel("Filled Color:");
    colorPanel.add(label);
    colorChoice = new JComboBox();

    for (int i = 0; i < COLOR_NAMES.length; i++) {
      colorChoice.addItem(COLOR_NAMES[i]);
    }
    colorPanel.add(colorChoice);
    colorChoice.addItemListener(this);

    JPanel listPanel = getListPanel();
    add(listPanel, BorderLayout.WEST);

    // create the canvas
    canvas = new DrawCanvas();
    add(canvas, BorderLayout.CENTER);
  } // end of constructor

  /**
   * Implementing ActionListener
   */
  @Override public void actionPerformed(ActionEvent event) {
    if (event.getSource() == circle) { // circle button
      canvas.setShape(DrawCanvas.CIRCLE);
    } else if (event.getSource() == roundRec) { // rounded rectangle button
      canvas.setShape(DrawCanvas.ROUNDED_RECTANGLE);
    } else if (event.getSource() == threeDRec) { // 3D rectangle button
      canvas.setShape(DrawCanvas.RECTANGLE_3D);
    } else if (event.getActionCommand().equals("Clear All")) {
      for (int i = 0; i < shapes.size(); i++) {
        shapes.remove(i);
      }
      updateShapeList();
      canvas.repaint();
    } else if (event.getActionCommand().equals("Remove Shape")) {
      String name = jList1.getSelectedValue();
      for (int i = 0; i < shapes.size(); i++) {
        if (shapes.get(i).toString().equals(name)) {
          shapes.remove(i);
          break;
        }
      }
      updateShapeList();
      canvas.repaint();
    }
  }

  /**
   * Implementing ItemListener
   * @param event
   */
  @Override public void itemStateChanged(ItemEvent event) {
    Color color = COLORS[colorChoice.getSelectedIndex()];
    canvas.setFilledColor(color);
  }

  /**
   * the main method
   */
public
  static void main(String[] argv) {
    // Create a frame
    Draw frame = new Draw();
    frame.setSize(FWIDTH, FHEIGHT);
    frame.setLocation(150, 100);

    // add window closing listener
        frame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent event) {
                System.exit(0);
  }
});

// Show the frame
frame.setVisible(true);
}

private
JPanel getListPanel() {
  JPanel p = new JPanel(new GridLayout(3, 1));
  p.setSize(100, 300);
  jScrollPane2 = new JScrollPane();
  jList1 = new JList<>();

  updateShapeList();
  jScrollPane2.setViewportView(jList1);
  p.add(jScrollPane2);

  JButton removeShape = new JButton("Remove Shape");
  removeShape.addActionListener(this);
  p.add(removeShape);

  JButton Clearall = new JButton("Clear All");
  Clearall.addActionListener(this);
  p.add(Clearall);
  return p;
}

/**
 * When ever a new item added or removed from the list
 * then we need to update the model of the list.
 */
public
void updateShapeList() {
  jList1.setModel(new javax.swing.AbstractListModel<String>() {
    String[] shapenames = getMenuNames();
  private
    String[] getMenuNames() {
      int i = 0;
      String[] names = new String[shapes.size() + 1];
      for (MyShape m : shapes) {
        names[i++] = m.toString();
      }
      return names;
    }

  public
    int getSize() { return shapenames.length; }
    @Override public String getElementAt(int i) {
      return shapenames[i];
    }
  });
}

class DrawCanvas extends Canvas implements MouseListener, MouseMotionListener {
  // Constants for shapes
public
  static final int CIRCLE = 1;
public
  static final int ROUNDED_RECTANGLE = 2;
public
  static final int RECTANGLE_3D = 3;

  // Coordinates of points to draw
private
  int x1, y1, x2, y2;

  // shape to draw
private
  int shape = CIRCLE;
private
  final int PAINT = 0; // do we need to draw current component
private
  final int NOPAINT = 1; // we dont need to draw current componet
private
  int paintOrRepaint = NOPAINT; // at the beginning we dont need to draw
                                /**
                              *Method to set the shape
                              *@param shape
                             */
public
  void setShape(int shape) { this.shape = shape; }

  // filled color
private
  Color filledColor = null;
  /**
*Method to set filled color
*@param color
*/
public
  void setFilledColor(Color color) { filledColor = color; }

  /**
*Constructor
*/
public
  DrawCanvas() {
    addMouseListener(this);
    addMouseMotionListener(this);
  } // end of constructor

  /**
*painting the component
*/
public
  void paint(Graphics g) {

    // the drawing area
    int x, y, width, height;

    // determine the upper-left corner of bounding rectangle
    x = Math.min(x1, x2);
    y = Math.min(y1, y2);

    // determine the width and height of bounding rectangle
    width = Math.abs(x1 - x2);
    height = Math.abs(y1 - y2);

    // current shape : by default it is a line after using a switch we update
    // this to
    // circle of rectangle
    Shape cur_shape = new Line2D.Double(x1, y1, x2, y2);
    switch (shape) {
    case ROUNDED_RECTANGLE:
      cur_shape = new RoundRectangle2D.Double(x, y, width, height, width / 4,
                                              height / 4);
      break;
    case CIRCLE:
      int diameter = Math.max(width, height);
      cur_shape = new Ellipse2D.Double(x, y, diameter, diameter);
      break;
    case RECTANGLE_3D:
      cur_shape = new Rectangle2D.Double(x, y, width, height);
      break;
    }

    // if we need to paint this component
    // first add it to the shapes list in the Draw class
    if (paintOrRepaint == PAINT) {
      MyShape sh = new MyShape(cur_shape, filledColor, shape);
      Draw.shapes.add(sh);
    }

    Graphics2D graphics = (Graphics2D)g;
    for (MyShape s : Draw.shapes) {
      if (s.fill != null)
        g.setColor(s.fill);
      else
        g.setColor(Color.BLACK);
      if (s.fill != null)
        graphics.fill(s.shape);
      else
        graphics.draw(s.shape);
    }
    updateShapeList(); // update the Jlist in the GUI
    setPaintOrRepaint(
        NOPAINT); // make the current componet not to draw next time
  }

  /**
*Implementing MouseListener
*@param event
*/
public
  void mousePressed(MouseEvent event) {
    x1 = event.getX();
    y1 = event.getY();
  }

public
  void mouseReleased(MouseEvent event) {
    x2 = event.getX();
    y2 = event.getY();
    // we have a new shape(componet) to draw
    // so set the paintOrRepaint to PAINT
    // so that repaint method can draw this
    // shape on the canvas
    setPaintOrRepaint(PAINT);
    repaint();
  }

public
  void mouseClicked(MouseEvent e) {}
public
  void mouseEntered(MouseEvent e) {}
public
  void mouseExited(MouseEvent e) {}

  /**
*Implementing MouseMotionListener
*@param event
*/
  @Override public void mouseDragged(MouseEvent event) {
    x2 = event.getX();
    y2 = event.getY();
  }

public
  void mouseMoved(MouseEvent e) {}

private
  void setPaintOrRepaint(int option) { paintOrRepaint = option; }
}
}

// class shape will store the details about the
// shape that we want to draw and do we need to
// fill it or not
class MyShape {
  Shape shape;
  Color fill;
  String shapeName;

  MyShape(Shape shape, Color filledColor, int shapeName) {
    this.shape = shape;
    this.fill = filledColor;
    this.shapeName = getName(shapeName);
  }

private
  String getName(int shapeName) {
    switch (shapeName) {
    case 1:
      return "Circle";
    case 2:
      return "Round Rectangle";
    case 3:
      return "Rectangle 3D";
    default:
      return "NoshapeName";
    }
  }
public
  String toString() {
    return shapeName + "(" + shape.getBounds().x + "," + shape.getBounds().y +
           ")";
  }
}