// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Diagnostics;
using System.Xml.XPath;
 
namespace MS.Internal.Xml.XPath
{
    internal class Axis : AstNode
    {
        private readonly AxisType _axisType;
        private AstNode? _input;
        private readonly string _prefix;
        private readonly string _name;
        private readonly XPathNodeType _nodeType;
        protected bool abbrAxis;
 
        public enum AxisType
        {
            Ancestor,
            AncestorOrSelf,
            Attribute,
            Child,
            Descendant,
            DescendantOrSelf,
            Following,
            FollowingSibling,
            Namespace,
            Parent,
            Preceding,
            PrecedingSibling,
            Self,
            None
        };
 
        // constructor
        public Axis(AxisType axisType, AstNode? input, string prefix, string name, XPathNodeType nodetype)
        {
            Debug.Assert(prefix != null);
            Debug.Assert(name != null);
            _axisType = axisType;
            _input = input;
            _prefix = prefix;
            _name = name;
            _nodeType = nodetype;
        }
 
        // constructor
        public Axis(AxisType axisType, AstNode? input)
            : this(axisType, input, string.Empty, string.Empty, XPathNodeType.All)
        {
            this.abbrAxis = true;
        }
 
        public override AstType Type { get { return AstType.Axis; } }
 
        public override XPathResultType ReturnType { get { return XPathResultType.NodeSet; } }
 
        public AstNode? Input
        {
            get { return _input; }
            set { _input = value; }
        }
 
        public string Prefix { get { return _prefix; } }
        public string Name { get { return _name; } }
        public XPathNodeType NodeType { get { return _nodeType; } }
        public AxisType TypeOfAxis { get { return _axisType; } }
        public bool AbbrAxis { get { return abbrAxis; } }
 
        // Used by AstTree in Schema
        private string? _urn = string.Empty;
        public string? Urn
        {
            get { return _urn; }
            set { _urn = value; }
        }
    }
}