Query.cs

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using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Xml;
using System.Xml.XPath;
using System.Xml.Xsl;
 
namespace MS.Internal.Xml.XPath;
 
[DebuggerDisplay("{ToString()}")]
internal abstract class Query : ResetableIterator
{
    public override int Count
    {
        get
        {
            if (count == -1)
            {
                Query query = (Query)Clone();
                query.Reset();
                count = 0;
                while (query.MoveNext())
                {
                    count++;
                }
            }
            return count;
        }
    }
 
    public virtual double XsltDefaultPriority => 0.5;
 
    public abstract XPathResultType StaticType { get; }
 
    public virtual QueryProps Properties => QueryProps.Merge;
 
    public Query()
    {
    }
 
    protected Query(Query other)
        : base(other)
    {
    }
 
    public override bool MoveNext()
    {
        return Advance() != null;
    }
 
    public virtual void SetXsltContext(XsltContext context)
    {
    }
 
    public abstract object Evaluate(XPathNodeIterator nodeIterator);
 
    public abstract XPathNavigator Advance();
 
    public virtual XPathNavigator MatchNode(XPathNavigator current)
    {
        throw XPathException.Create(System.SR.Xp_InvalidPattern);
    }
 
    [return: NotNullIfNotNull("input")]
    public static Query Clone(Query input)
    {
        if (input != null)
        {
            return (Query)input.Clone();
        }
        return null;
    }
 
    [return: NotNullIfNotNull("input")]
    protected static XPathNodeIterator Clone(XPathNodeIterator input)
    {
        return input?.Clone();
    }
 
    [return: NotNullIfNotNull("input")]
    protected static XPathNavigator Clone(XPathNavigator input)
    {
        return input?.Clone();
    }
 
    public static bool Insert(List<XPathNavigator> buffer, XPathNavigator nav)
    {
        int num = 0;
        int num2 = buffer.Count;
        if (num2 != 0)
        {
            switch (CompareNodes(buffer[num2 - 1], nav))
            {
            case XmlNodeOrder.Same:
                return false;
            case XmlNodeOrder.Before:
                buffer.Add(nav.Clone());
                return true;
            }
            num2--;
        }
        while (num < num2)
        {
            int median = GetMedian(num, num2);
            switch (CompareNodes(buffer[median], nav))
            {
            case XmlNodeOrder.Same:
                return false;
            case XmlNodeOrder.Before:
                num = median + 1;
                break;
            default:
                num2 = median;
                break;
            }
        }
        buffer.Insert(num, nav.Clone());
        return true;
    }
 
    private static int GetMedian(int l, int r)
    {
        return l + r >>> 1;
    }
 
    public static XmlNodeOrder CompareNodes(XPathNavigator l, XPathNavigator r)
    {
        XmlNodeOrder xmlNodeOrder = l.ComparePosition(r);
        if (xmlNodeOrder == XmlNodeOrder.Unknown)
        {
            XPathNavigator xPathNavigator = l.Clone();
            xPathNavigator.MoveToRoot();
            string baseURI = xPathNavigator.BaseURI;
            if (!xPathNavigator.MoveTo(r))
            {
                xPathNavigator = r.Clone();
            }
            xPathNavigator.MoveToRoot();
            string baseURI2 = xPathNavigator.BaseURI;
            int num = string.CompareOrdinal(baseURI, baseURI2);
            xmlNodeOrder = ((num >= 0) ? ((num > 0) ? XmlNodeOrder.After : XmlNodeOrder.Unknown) : XmlNodeOrder.Before);
        }
        return xmlNodeOrder;
    }
 
    protected XPathResultType GetXPathType(object value)
    {
        if (value is XPathNodeIterator)
        {
            return XPathResultType.NodeSet;
        }
        if (value is string)
        {
            return XPathResultType.String;
        }
        if (value is double)
        {
            return XPathResultType.Number;
        }
        if (value is bool)
        {
            return XPathResultType.Boolean;
        }
        return (XPathResultType)4;
    }
}