LegacyFileCopier.cs

using System.IO;

public class LegacyFileCopier
{
    public void CopyFile(string sourceFilePath, string destinationDirectoryPath)
    {
        if (!Directory.Exists(destinationDirectoryPath))
        {
            Directory.CreateDirectory(destinationDirectoryPath);
        }

        var fileName = Path.GetFileName(sourceFilePath);
        var destFileName = Path.Combine(destinationDirectoryPath, fileName);
        File.Copy(sourceFilePath, destFileName);
    }
}