using System;
using System.Collections.Generic;

namespace AspClassic.Parser;

/// <summary>
/// A parse tree for an Else If statement.
/// </summary>
public sealed class ElseIfStatement : Statement
{
	private readonly Expression _Expression;

	private readonly Location _ThenLocation;

	/// <summary>
	/// The conditional expression.
	/// </summary>
	public Expression Expression => _Expression;

	/// <summary>
	/// The location of the 'Then', if any.
	/// </summary>
	public Location ThenLocation => _ThenLocation;

	/// <summary>
	/// Constructs a new parse tree for an Else If statement.
	/// </summary>
	/// <param name="expression">The conditional expression.</param>
	/// <param name="thenLocation">The location of the 'Then', if any.</param>
	/// <param name="span">The location of the parse tree.</param>
	/// <param name="comments">The comments for the parse tree.</param>
	public ElseIfStatement(Expression expression, Location thenLocation, Span span, IList<Comment> comments)
		: base(TreeType.ElseIfStatement, span, comments)
	{
		if (expression == null)
		{
			throw new ArgumentNullException("expression");
		}
		SetParent(expression);
		_Expression = expression;
		_ThenLocation = thenLocation;
	}

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