using System;
using System.Collections.Generic;

namespace AspClassic.Parser;

/// <summary>
/// A parse tree for an Imports statement that aliases a type or namespace.
/// </summary>
public sealed class AliasImport : Import
{
	private readonly SimpleName _Name;

	private readonly Location _EqualsLocation;

	private readonly TypeName _AliasedTypeName;

	/// <summary>
	/// The alias name.
	/// </summary>
	public SimpleName Name => _Name;

	/// <summary>
	/// The location of the '='.
	/// </summary>
	public Location EqualsLocation => _EqualsLocation;

	/// <summary>
	/// The name being aliased.
	/// </summary>
	public TypeName AliasedTypeName => _AliasedTypeName;

	/// <summary>
	/// Constructs a new aliased import parse tree.
	/// </summary>
	/// <param name="name">The name of the alias.</param>
	/// <param name="equalsLocation">The location of the '='.</param>
	/// <param name="aliasedTypeName">The name being aliased.</param>
	/// <param name="span">The location of the parse tree.</param>
	public AliasImport(SimpleName name, Location equalsLocation, TypeName aliasedTypeName, Span span)
		: base(TreeType.AliasImport, span)
	{
		if (aliasedTypeName == null)
		{
			throw new ArgumentNullException("aliasedTypeName");
		}
		if (name == null)
		{
			throw new ArgumentNullException("name");
		}
		SetParent(name);
		SetParent(aliasedTypeName);
		_Name = name;
		_EqualsLocation = equalsLocation;
		_AliasedTypeName = aliasedTypeName;
	}

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