package painting;

import javax.swing.SwingUtilities;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.BorderFactory;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseAdapter;

public class SwingPaintDemo4 {

    public static void main(String[] args) {

        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }

    private static void createAndShowGUI() {
        System.out.println("Created GUI on EDT? "+
                SwingUtilities.isEventDispatchThread());
        JFrame f = new JFrame("Swing Paint Demo");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(new MyPanel3());
        f.setSize(250,250);
        f.setVisible(true);
    }

}

class MyPanel3 extends JPanel {

    RedSquare redSquare = new RedSquare();
    RedSquare redSquare2 = new RedSquare();

    public MyPanel3() {

        setBorder(BorderFactory.createLineBorder(Color.black));

        addMouseListener(new MouseAdapter(){
            public void mousePressed(MouseEvent e){
                moveSquare(e.getX(),e.getY());
            }
        });

        addMouseMotionListener(new MouseAdapter(){
            public void mouseDragged(MouseEvent e){
                moveSquare(e.getX(),e.getY());
            }
        });

    }

    private void moveSquare(int x, int y){

        // Current square state, stored as final variables
        // to avoid repeat invocations of the same methods.
        final int CURR_X = redSquare.getX();
        final int CURR_Y = redSquare.getY();
        final int CURR_W = redSquare.getWidth();
        final int CURR_H = redSquare.getHeight();
        final int OFFSET = 1;

        if ((CURR_X!=x) || (CURR_Y!=y)) {

            // The square is moving, repaint background
            // over the old square location.
            repaint(CURR_X,CURR_Y,CURR_W+OFFSET,CURR_H+OFFSET);

            // Update coordinates.
            redSquare.setX(x);
            redSquare.setY(y);

            // Repaint the square at the new location.
            repaint(redSquare.getX(), redSquare.getY(),
                    redSquare.getWidth()+OFFSET,
                    redSquare.getHeight()+OFFSET);
        }
    }

    public Dimension getPreferredSize() {
        return new Dimension(250,200);
    }

    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.drawString("This is my custom Panel!",10,20);
        System.out.println(getSize());
        redSquare.paintSquare(g);
        redSquare2.paintSquare(g);
    }
}

class RedSquare{

    private int xPos = 50;
    private int yPos = 50;
    private int width = 20;
    private int height = 20;

    public void setX(int xPos){
        this.xPos = xPos;
    }

    public int getX(){
        return xPos;
    }

    public void setY(int yPos){
        this.yPos = yPos;
    }

    public int getY(){
        return yPos;
    }

    public int getWidth(){
        return width;
    }

    public int getHeight(){
        return height;
    }

    public void paintSquare(Graphics g){
        g.setColor(Color.RED);
        g.fillRect(xPos,yPos,width,height);
        g.setColor(Color.BLACK);
        g.drawRect(xPos,yPos,width,height);
    }
}