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 */
package lab77;

import java.util.Random;
import java.util.Timer;
import java.util.TimerTask;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Graphics;
import javax.microedition.midlet.*;

/**
 * @author admin
 */
public class Midlet extends MIDlet {

    Display ekran;
    PadajacySnieg zamiec = new PadajacySnieg();
    Grawitacja padaSnieg = new Grawitacja();
    Timer timer = new Timer();

    public Midlet() {
        ekran = Display.getDisplay(this);
    }

    public void startApp() {
        ekran.setCurrent(zamiec);
        timer.schedule(padaSnieg, 10, 10);
    }

    public void pauseApp() {
    }

    protected void exit() {
        timer.cancel();
        destroyApp(true);
        notifyDestroyed();

    }

    public void destroyApp(boolean unconditional) {
    }

    class Grawitacja extends TimerTask {

        public void run() {
            zamiec.scroll();
        }
    }

    class PadajacySnieg extends Canvas {

        int height;
        int width;
        int i = 1;
        int size;
        int[] snieg;
        int[] tab_y;
        Random generator = new Random();
        boolean painting = false;

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

        public void scroll() {
            if (painting) {
                return;
            }
            if (snieg[height - 1] > 0) {
                tab_y[snieg[height - 1]] += 1;
            }
            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);
            int y = 0, x = 0;
            for (y = 0; y < height; ++y) {
                x = snieg[y];
                if (x == -1) {
                    continue;
                }
                g.drawLine(x, y, x, y);
            }
            for (int i = 0; i < tab_y.length; i++) {
                if (i < tab_y.length - 1) {
                    if (tab_y[i + 1] > tab_y[i] + 2) {
                        g.drawLine(i, height, i, height - tab_y[i] + 1);
                    } else {
                        g.drawLine(i, height, i, height - tab_y[i]);
                    }
                }
            }
            painting = false;
        }
    }

    protected void keyPressed(int keyCode) {
        exit();
    }
}