XPathSortComparer.cs

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using System.Collections;
using System.Collections.Generic;
using System.Xml.XPath;
 
namespace MS.Internal.Xml.XPath;
 
internal sealed class XPathSortComparer : IComparer<SortKey>
{
    private Query[] _expressions;
 
    private IComparer[] _comparers;
 
    private int _numSorts;
 
    public int NumSorts => _numSorts;
 
    public XPathSortComparer(int size)
    {
        if (size <= 0)
        {
            size = 3;
        }
        _expressions = new Query[size];
        _comparers = new IComparer[size];
    }
 
    public XPathSortComparer()
        : this(3)
    {
    }
 
    public void AddSort(Query evalQuery, IComparer comparer)
    {
        if (_numSorts == _expressions.Length)
        {
            Query[] array = new Query[_numSorts * 2];
            IComparer[] array2 = new IComparer[_numSorts * 2];
            for (int i = 0; i < _numSorts; i++)
            {
                array[i] = _expressions[i];
                array2[i] = _comparers[i];
            }
            _expressions = array;
            _comparers = array2;
        }
        if (evalQuery.StaticType == XPathResultType.NodeSet || evalQuery.StaticType == XPathResultType.Any)
        {
            evalQuery = new StringFunctions(Function.FunctionType.FuncString, new Query[1] { evalQuery });
        }
        _expressions[_numSorts] = evalQuery;
        _comparers[_numSorts] = comparer;
        _numSorts++;
    }
 
    public Query Expression(int i)
    {
        return _expressions[i];
    }
 
    int IComparer<SortKey>.Compare(SortKey x, SortKey y)
    {
        int num = 0;
        for (int i = 0; i < x.NumKeys; i++)
        {
            num = _comparers[i].Compare(x[i], y[i]);
            if (num != 0)
            {
                return num;
            }
        }
        return x.OriginalPosition - y.OriginalPosition;
    }
 
    internal XPathSortComparer Clone()
    {
        XPathSortComparer xPathSortComparer = new XPathSortComparer(_numSorts);
        for (int i = 0; i < _numSorts; i++)
        {
            xPathSortComparer._comparers[i] = _comparers[i];
            xPathSortComparer._expressions[i] = (Query)_expressions[i].Clone();
        }
        xPathSortComparer._numSorts = _numSorts;
        return xPathSortComparer;
    }
}