C-Sharp to JavaScript Quest Script help!

Unity Engine
1

Hey guys, I made a C# Quest script. However, I want to convert it into JavaScript because I have more knowledge with JavaScript and I need some scripting Guru to tell me what is wrong with this Script. I know it contains SOME C# coding but I need that to be changed into JavaScript.

2 
private var showDialog = false;
private var doQuest = false;

function OnGUI() {

GUILayout.BeginArea(Rect(200, 200, 200, 200));
	if(showDialog!doQuest){
	
		GUILayout.Label("Hello, my name is Gerald!");
		GUILayout.Label("Is it possible if you deliver a message to my Brother William?");
		if (GUILayout.Button ("Sure, I can do that!")){
		
		doQuest = true;
		
		showDialog = false;
		
		Debug.Log("Quest Accepted");
		}
		
			if (GUILayout.Button ("Sorry, not now.")){
			
				showDialog = false;
				
				Debug.Log("Quest Declined");
			
			}
		}
		if (showDialog&doQuest){
		
		GUILayout.Label("Thank you my good friend, you'll find William located near the east side of the chapel!");
		if (GUILayout.Button ("Continue Quest")){
		
		showDialog = false;
		
		Debug.Log("Quest Accepted");
		}
	}
	
	GUILayout.EndArea();

}

	function OnTriggerEnter() {
	
		showDialog = true;
	}
	
	function OnTriggerExit() {
	
		showDialog = false;
	
	}