package lab7_snieg;

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.Graphics;
import javax.microedition.midlet.*;

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);

    }

    protected void destroyApp(boolean unconditional) {
    }

    protected void startApp() {

        ekran.setCurrent(zamiec);
        timer.schedule(padaSnieg, 10, 10);

    }

    protected void pauseApp() {
    }

    public void exit() {
        timer.cancel();

        destroyApp(true);
        notifyDestroyed();

    }

    class Grawitacja extends TimerTask {

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

        }

    }

    class PadajacySnieg extends Canvas {

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

        public PadajacySnieg() {

            height = getHeight();
            width = getWidth();
            snieg = new int[height];

            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);

            }

            painting = false;
        }

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

    }
}