using System;
using System.Collections.Generic;

namespace AspClassic.Parser;

/// <summary>
/// A parse tree for a dictionary lookup expression.
/// </summary>
public sealed class DictionaryLookupExpression : Expression
{
	private readonly Expression _Qualifier;

	private readonly Location _BangLocation;

	private readonly SimpleName _Name;

	/// <summary>
	/// The dictionary expression.
	/// </summary>
	public Expression Qualifier => _Qualifier;

	/// <summary>
	/// The location of the '!'.
	/// </summary>
	public Location BangLocation => _BangLocation;

	/// <summary>
	/// The name to look up.
	/// </summary>
	public SimpleName Name => _Name;

	/// <summary>
	/// Constructs a new parse tree for a dictionary lookup expression.
	/// </summary>
	/// <param name="qualifier">The dictionary expression.</param>
	/// <param name="bangLocation">The location of the '!'.</param>
	/// <param name="name">The name to look up..</param>
	/// <param name="span">The location of the parse tree.</param>
	public DictionaryLookupExpression(Expression qualifier, Location bangLocation, SimpleName name, Span span)
		: base(TreeType.DictionaryLookupExpression, span)
	{
		if (name == null)
		{
			throw new ArgumentNullException("name");
		}
		SetParent(qualifier);
		SetParent(name);
		_Qualifier = qualifier;
		_BangLocation = bangLocation;
		_Name = name;
	}

	protected override void GetChildTrees(IList<Tree> childList)
	{
		Tree.AddChild(childList, Qualifier);
		Tree.AddChild(childList, Name);
	}
}