AbcPdf in ASP.Net Mvc

AbcPdfDocumentGenerator.cs

    public class AbcPdfDocumentGenerator : IDocumentGenerator
    {
        public string ContentType
        {
            get { return "application/pdf"; }
        }

        public string FileExtension
        {
            get { return "pdf"; }
        }

        public AbcPdfDocumentGenerator(string licenceKey)
        {
            if (!string.IsNullOrEmpty(licenceKey))
                XSettings.InstallSystemLicense(licenceKey);
        }

        public Stream Generate(Uri httpAddress)
        {
            return GenerateDocumentStream(doc => doc.AddImageUrl(httpAddress.ToString(), true, 1024, true));
        }

        public Stream Generate(string html)
        {
            return GenerateDocumentStream(doc => doc.AddImageHtml(html, true, 1024, true));
        }

        public Stream Generate(Stream html, Encoding encoding)
        {
            using (var rdr = new StreamReader(html, encoding))
                return Generate(rdr.ReadToEnd());
        }

        private Stream GenerateDocumentStream(Func<Doc, int> initialPage)
        {
            using (var doc = new Doc())
            {
                doc.Rect.Inset(0, 25);

                doc.HtmlOptions.Engine = EngineType.Gecko;
                doc.HtmlOptions.ImageQuality = 70; //101 = lossless
                doc.HtmlOptions.AddLinks = true;
                doc.HtmlOptions.AddTags = true;
                doc.HtmlOptions.BrowserWidth = 1024;
                doc.HtmlOptions.FontEmbed = true;
                doc.HtmlOptions.InitialWidth = 1024;
                doc.HtmlOptions.TargetLinks = true;

                doc.Font = doc.AddFont("Arial");

                var pdfsettingsid = doc.AddObject("<< >>");
                doc.SetInfo(-1, "/Info:Ref", pdfsettingsid.ToString());
                //doc.SetInfo(pdfsettingsid, "/Title:Text", title);
                doc.SetInfo(pdfsettingsid, "/Author:Text", "Toll");
                //doc.SetInfo(pdfsettingsid, "/Subject:Text", title);
                //doc.SetInfo(pdfsettingsid, "/Keywords:Text", "Toll,Visa");
                doc.SetInfo(pdfsettingsid, "/Creator:Text", "Toll");
                doc.SetInfo(pdfsettingsid, "/Producer:Text", "Toll");
                var date = string.Format("D:{0}", DateTime.Now.ToString("YYYYmmdd"));
                doc.SetInfo(pdfsettingsid, "/CreationDate:Text", date);
                doc.SetInfo(pdfsettingsid, "/ModDate:Text", date);
                doc.SetInfo(pdfsettingsid, "/Trapped:Name", "False");

                var htmlId = initialPage(doc); //Add the initial page of the pdf document
                while (true) //Until the doc is no longer chainable, loop
                {
                    if (!doc.Chainable(htmlId)) break;
                    doc.Page = doc.AddPage();
                    htmlId = doc.AddImageToChain(htmlId); //Add new page
                }

                for (var i = 1; i <= doc.PageCount; i++)
                {
                    doc.PageNumber = i;
                    doc.Flatten();
                }

                //return stream of the pdf
                var memoryStream = new MemoryStream();
                doc.Save(memoryStream);
                memoryStream.Position = 0;
                return memoryStream;
            }
        }
    }

DocumentGenerationActionFilter.cs

    public class DocumentGenerationActionFilter : IActionFilter
    {
        private readonly IDocumentGenerator _documentGenerator;

        public DocumentGenerationActionFilter(IDocumentGenerator documentGenerator)
        {
            _documentGenerator = documentGenerator;
        }

        public void OnActionExecuting(ActionExecutingContext filterContext)
        {
        }

        public void OnActionExecuted(ActionExecutedContext filterContext)
        {
            if ((filterContext.RouteData.Values["pdf"] ?? string.Empty).ToString() == "pdf" && filterContext.Result.GetType().IsAssignableFrom(typeof (ViewResult)))
            {
                var view = (ViewResult) filterContext.Result;
                var baseUrl = filterContext.HttpContext.Request.Url;
                var content = filterContext.Controller.ViewResultToString(view).Replace("<head>", "<head><base href=\"" + baseUrl + "\" />");
                var documentStream = _documentGenerator.Generate(content);
                filterContext.Result = new FileStreamResult(documentStream, _documentGenerator.ContentType)
                    {
                        FileDownloadName = Path.ChangeExtension(filterContext.RouteData.GetRequiredString("action"), _documentGenerator.FileExtension)
                    };
            }
        }
    }

IDocumentGenerator.cs

    public interface IDocumentGenerator
    {
        string ContentType { get; }
        string FileExtension { get; }
        Stream Generate(Uri httpAddress);
        Stream Generate(string html);
        Stream Generate(Stream html, Encoding encoding);
    }

MvcExtensions.cs

    public static class MvcExtensions
    {
        public static string ViewResultToString(this ControllerBase controller, ViewResult viewResult)
        {
            if (string.IsNullOrEmpty(viewResult.ViewName))
                viewResult.ViewName = controller.ControllerContext.RouteData.GetRequiredString("action");

            viewResult.View = viewResult.ViewEngineCollection.FindView(controller.ControllerContext, viewResult.ViewName, viewResult.MasterName).View;

            // init string writer
            using (var sw = new StringWriter())
            {
                // get the view context
                var viewContext = new ViewContext(controller.ControllerContext, viewResult.View, controller.ViewData, controller.TempData, sw);
                // render the view
                viewResult.View.Render(viewContext, sw);
                // return the string
                return sw.ToString();
            }
        }
    }