function SystemOperation() {
  var that=this;
  
  this.moveBigCircle = function(x, y) {
    moveBigCircle(x, y);
  }

  function moveBigCircle(x, y) {
    if (parseInt(get("bigCircle").style.left) + x == 250) {
      x = -1;
    }

    if (parseInt(get("bigCircle").style.left) + x == 82) {
      x = 1;
    }

    if (parseInt(get("bigCircle").style.top) + y == 300) {
      y = -1;
    }

    if (parseInt(get("bigCircle").style.top) + y == 82) {
      y = 1;
    }

    var left = parseInt(get("bigCircle").style.left) + x + "px";
    var top = parseInt(get("bigCircle").style.top) + y + "px";
    
    
    if ( (parseInt(left) < 382) && (parseInt(left) > 0) ) {
      get("bigCircle").style.left = left;
    }
    if ( (parseInt(top) < 392) && (parseInt(top) > 0) ) {
      get("bigCircle").style.top = top;
    }
  }

  this.moveSmallCircle = function(x, y, angle) {
    moveSmallCircle(x, y, angle);
  };

  function moveSmallCircle(x, y, angle) {
    if (parseInt(get("smallCircle").style.left) + x == 250) {
      x = -1;
    }

    if (parseInt(get("smallCircle").style.left) + x == 82) {
      x = 1;
    }

    if (parseInt(get("smallCircle").style.top) + y == 300) {
      y = -1;
    }

    if (parseInt(get("smallCircle").style.top) + y == 82) {
      y = 1;
    }

    get("smallCircle").src = "images/laboratory/nuke/smallcircle/smallcircleAngle." + angle + ".png";
    var left = parseInt(get("smallCircle").style.left) + x + "px";
    var top = parseInt(get("smallCircle").style.top) + y + "px";
    if ( (parseInt(left) < 382) && (parseInt(left) > 0) ) {
      get("smallCircle").style.left = left;
    }
    if ( (parseInt(top) < 392) && (parseInt(top) > 0) ) {
      get("smallCircle").style.top = top;
    }
  }

}

systemOperation = new SystemOperation();