package test;

import java.awt.*;
import javax.swing.*;

public class TestGrid extends JFrame{

    public static void main(String[] args) {  
        TestGrid game = new TestGrid();  
        game.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
        game.setVisible(true);  
    } 
    
    public TestGrid(){
        super();
        this.setTitle("just a test!");
        this.setSize(600, 400);
        this.getContentPane().setLayout(new BorderLayout());

        DrawGrid(resultPanel);
        this.add(resultPanel,BorderLayout.CENTER);
    }
    

    private void DrawGrid(JPanel panel) {
        width = panel.getWidth();
        height = panel.getHeight();

        section_width = width / 20;
        section_height = height / 20;

        remainder_width = width - section_width * 20;
        remainder_height = height - section_height * 20;

        Graphics graphics = panel.getGraphics();
        graphics.clearRect(0, 0, width, height);
                
        for (int i = 0; i <= 20; i++) {
            graphics.drawLine(remainder_width / 2 + section_width * i,
                    remainder_height / 2, 
                    remainder_width / 2 + section_width * i,
                    height - remainder_height / 2);
        }

        for (int i = 0; i <= 20; i++) {
            graphics.drawLine(remainder_width / 2, 
                    remainder_height / 2 + section_height * i,
                    width - remainder_width / 2,
                    remainder_height / 2 + section_height * i);
        }
    }
    
    private int width ;
    private int height ;
    private int section_width;
    private int section_height;
    private int remainder_width;
    private int remainder_height;
    private JPanel resultPanel = new JPanel();
}