public void currentScreen() {
        if (stage == play) {
            if (controller.target.hp < 1 || controller.target.isZombie())
                stage = lose;
            else if (world.ticks >= world.ticksPerMinute * 720)
                stage = win;
        }

        switch (stage) {
            case start: startScreen(); break;
            case win: winScreen(); break;
            case lose: loseScreen(); break;
            case play: playScreen(); break;
            case help: helpScreen(); break;
            default: wtfScreen(); break;
        }
        panel.repaint();
    }