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

/**
 * Classe di utility
 */
public class HashUtil {

	/*
	 * Visualizza il grafico points
	 */
	public static void show(java.util.List<int[]> plot) throws Exception {

			JFrame f     = new JFrame();
			Container cp = f.getContentPane();
			MyJPanel mp  = new MyJPanel(plot);
			
			cp.add(mp, BorderLayout.CENTER);
			mp.setPreferredSize(new Dimension(800, 600));
			
			f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
			f.pack();
			f.setVisible(true);
	}
	
	/*
	 * Metodo di generazione delle chiavi esadecimali
	 */
    public static String randomKey() {
		String uuid = UUID.randomUUID().toString();
		return uuid.substring(0,8);
    }
	
	/*
	 * Classe grafica
	 */	
	static class MyJPanel extends JPanel {
	
	    private static final int     ticlen = 20;
		private static final Color[] colors = {Color.BLACK, Color.RED, Color.GREEN};
	
		java.util.List<int[]> plot;

		public MyJPanel(java.util.List<int[]> plot) {
			super();
			this.plot = plot;
		}
		
		public void paintComponent(Graphics g) {
			super.paintComponent(g);
			Graphics2D g2 = (Graphics2D) g;
			g2.setStroke(new BasicStroke(10));
			g2.scale(1,-1);
			g2.translate(0,-getHeight());
			int c = 0;
			
			for (int[] points : plot) {
				g2.setColor(colors[c++ % colors.length]);
				for (int i = 0; i < points.length-1; i++) {
					g.drawLine(   i *ticlen,   points[i]*ticlen,
							   (i+1)*ticlen, points[i+1]*ticlen);
				}
			}
		}
	
	}

}