package lab7;

import java.util.Random;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Graphics;

public class PadajacySnieg extends Canvas{

    int height;
    int width;
    int snieg[];
    int warstwaSniegu[];
    Random generator = new Random();
    boolean painting = false;

    public PadajacySnieg() {
        height = getHeight();
        width = getWidth();
        snieg = new int[height];
        warstwaSniegu = new int[width];
        for ( int i = 0; i < width; i++) {
            warstwaSniegu[i] = 0;
        }
        for (int i = 0; i < height; ++i) {
            snieg[i] = -1;
        }
    }

    public void scroll() {
        if (painting) {
            return;
        }
        for (int i = height - 1; i > 0; --i) {
            snieg[i] = snieg[i - 1];
        }
        snieg[0] = Math.abs((generator.nextInt() % (2 * width)) / 2);
        repaint();
    }

    protected void paint(Graphics g) {
        painting = true;
        g.setColor(128, 128, 128);
        g.fillRect(0, 0, width, height);
        g.setColor(255, 255, 255);
        for (int y = 0; y < height; ++y) {
            int x = snieg[y];
            if (x == -1) {
                continue;
            }
            g.drawLine(x, y, x, y);
            if(y == height - 1) {
                warstwaSniegu[x]++;
            }
        }
        for (int i = 0; i < warstwaSniegu.length; i++) {
            if(warstwaSniegu[i] != 0) {
                g.drawLine(i, height - warstwaSniegu[i], i, height);

            }
        }
        painting = false;
    }

}