// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
#if CODEANALYSIS_V3_OR_BETTER
 
using System;
using System.IO;
 
namespace Analyzer.Utilities
{
    internal static class PathHelper
    {
        private static readonly char[] DirectorySeparatorCharacters = { Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar };
 
        public static ReadOnlySpan<char> GetFileName(string? path)
        {
            if (RoslynString.IsNullOrEmpty(path))
                return ReadOnlySpan<char>.Empty;
 
            var lastSeparator = path.LastIndexOfAny(DirectorySeparatorCharacters);
            if (lastSeparator < 0)
                return path.AsSpan();
 
            return path.AsSpan()[(lastSeparator + 1)..];
        }
    }
}
 
#endif