// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)

using System;

namespace ICSharpCode.NRefactory.VB
{
	/// <summary>
	/// Interface for all specials.
	/// </summary>
	public interface ISpecial
	{
		Location StartPosition { get; }
		Location EndPosition { get; }
		
		object AcceptVisitor(ISpecialVisitor visitor, object data);
	}
	
	public interface ISpecialVisitor
	{
		object Visit(ISpecial special, object data);
		object Visit(BlankLine special, object data);
		object Visit(Comment special, object data);
		object Visit(PreprocessingDirective special, object data);
	}
	
	public abstract class AbstractSpecial : ISpecial
	{
		public abstract object AcceptVisitor(ISpecialVisitor visitor, object data);
		
		protected AbstractSpecial(Location position)
		{
			this.StartPosition = position;
			this.EndPosition = position;
		}
		
		protected AbstractSpecial(Location startPosition, Location endPosition)
		{
			this.StartPosition = startPosition;
			this.EndPosition = endPosition;
		}
		
		public Location StartPosition { get; set; }
		public Location EndPosition { get; set; }
		
		public override string ToString()
		{
			return String.Format("[{0}: Start = {1}, End = {2}]",
			                     GetType().Name, StartPosition, EndPosition);
		}
	}
}