// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Collections;
using MS.Internal.Xml.XPath;
 
namespace System.Xml.XPath
{
    public enum XmlSortOrder
    {
        Ascending = 1,
        Descending = 2,
    }
 
    public enum XmlCaseOrder
    {
        None = 0,
        UpperFirst = 1,
        LowerFirst = 2,
    }
 
    public enum XmlDataType
    {
        Text = 1,
        Number = 2,
    }
 
    public enum XPathResultType
    {
        Number = 0,
        String = 1,
        Boolean = 2,
        NodeSet = 3,
        Navigator = XPathResultType.String,
        Any = 5,
        Error
    };
 
    public abstract class XPathExpression
    {
        internal XPathExpression() { }
 
        public abstract string Expression { get; }
 
        public abstract void AddSort(object expr, IComparer comparer);
 
        public abstract void AddSort(object expr, XmlSortOrder order, XmlCaseOrder caseOrder, string lang, XmlDataType dataType);
 
        public abstract XPathExpression Clone();
 
        public abstract void SetContext(XmlNamespaceManager nsManager);
 
        public abstract void SetContext(IXmlNamespaceResolver? nsResolver);
 
        public abstract XPathResultType ReturnType { get; }
 
        public static XPathExpression Compile(string xpath)
        {
            return Compile(xpath, /*nsResolver:*/null);
        }
 
        public static XPathExpression Compile(string xpath, IXmlNamespaceResolver? nsResolver)
        {
            bool hasPrefix;
            Query query = new QueryBuilder().Build(xpath, out hasPrefix);
            CompiledXpathExpr expr = new CompiledXpathExpr(query, xpath, hasPrefix);
            if (null != nsResolver)
            {
                expr.SetContext(nsResolver);
            }
            return expr;
        }
    }
}