Unity3d code clip : auto height lable and mouse touchable scrolling

var wasScrolling : boolean = false;
var scrollPosition : Vector2;
var longString = "This is a long-ish string This is an sized label. This is an sized label. This is an sized label. This is an sized label. This is an sized label. ";
function OnGUI () {

 var rectForDescription : Rect = Rect(100,100,100,100);
 
 GUILayout.BeginArea(rectForDescription);
 scrollPosition = GUILayout.BeginScrollView (scrollPosition, GUILayout.Width (100), GUILayout.Height (100));
 GUILayout.Label (longString);
 GUILayout.EndScrollView ();
 GUILayout.EndArea();
 
 if( Event.current.type==EventType.MouseDown && rectForDescription.Contains(Event.current.mousePosition) ) {
  wasScrolling = true;
  print("down");
 }
 
 if( Event.current.type==EventType.MouseDrag && wasScrolling==true ) {
  print(Event.current.delta.y);
  scrollPosition.y+=Event.current.delta.y;
 }
 
 if( Event.current.type==EventType.MouseUp && wasScrolling == true) {
  print("end scrolling");
  wasScrolling = false;
 }
 

}