PdfEngine

using System;
using System.Web;

/// Autor: Raphael A. F. Cardoso - www.csharpbrasil.com.br
namespace Br.CsharpBrasil
{

    public class PdfEngine
    {
        private iTextSharp.text.Rectangle rectangle = iTextSharp.text.PageSize.A4;

        #region Enumeration

        public enum Orientation
        {
            Portrait = 0,
            Landscape = 0
        }

        public enum PageSize
        {
            A4 = 0,
            LETTER = 1
        }

        #endregion

        #region Constructor

        public PdfEngine()
        {
            this.rectangle = new iTextSharp.text.Rectangle(iTextSharp.text.PageSize.A4);
        }

        public PdfEngine(PageSize pageSize)
        {
            var pSize = getPageSize(pageSize);
            this.rectangle = new iTextSharp.text.Rectangle(pSize);
        }

        public PdfEngine(Orientation orientation)
        {
            this.rectangle = new iTextSharp.text.Rectangle(iTextSharp.text.PageSize.A4);
            if (orientation == Orientation.Landscape) this.rectangle = this.rectangle.Rotate();
        }

        public PdfEngine(Orientation orientation, PageSize pageSize)
        {
            var pSize = getPageSize(pageSize);
            this.rectangle = new iTextSharp.text.Rectangle(pSize);
            if (orientation == Orientation.Landscape) this.rectangle = this.rectangle.Rotate();
        }

        #endregion

        #region Private Methods

        private iTextSharp.text.Rectangle getPageSize(PageSize pageSize)
        {
            var pSize = iTextSharp.text.PageSize.A4;

            switch (pageSize)
            {
                case PageSize.A4:
                    pSize = iTextSharp.text.PageSize.A4;
                    break;
                case PageSize.LETTER:
                    pSize = iTextSharp.text.PageSize.LETTER;
                    break;
                default:
                    pSize = iTextSharp.text.PageSize.A4;
                    break;
            }

            return pSize;
        }

        private string getImage(string input)
        {
            if (input == null) return string.Empty;

            string tempInput = input;
            string pattern = @"<img(.|\n)+?>";
            string src = string.Empty;
            HttpContext context = HttpContext.Current;

            foreach (System.Text.RegularExpressions.Match m in System.Text.RegularExpressions.Regex.Matches(input, pattern, System.Text.RegularExpressions.RegexOptions.IgnoreCase | System.Text.RegularExpressions.RegexOptions.Multiline | System.Text.RegularExpressions.RegexOptions.RightToLeft))
            {
                if (m.Success)
                {
                    string tempM = m.Value;
                    string pattern1 = "src=[\'|\"](.+?)[\'|\"]";
                    System.Text.RegularExpressions.Regex reImg = new System.Text.RegularExpressions.Regex(pattern1, System.Text.RegularExpressions.RegexOptions.IgnoreCase | System.Text.RegularExpressions.RegexOptions.Multiline);
                    System.Text.RegularExpressions.Match mImg = reImg.Match(m.Value);

                    if (mImg.Success)
                    {
                        src = mImg.Value.ToLower().Replace("src=", "").Replace("\"", "");

                        if (src.ToLower().Contains("http://") == false)
                        {
                            src = "src=\"" + context.Request.Url.Scheme + "://" + System.IO.Path.Combine(context.Request.Url.Authority, src).Replace("\\", "/") + "\"";
                            try
                            {
                                tempM = tempM.Remove(mImg.Index, mImg.Length);
                                tempM = tempM.Insert(mImg.Index, src);

                                tempInput = tempInput.Remove(m.Index, m.Length);
                                tempInput = tempInput.Insert(m.Index, tempM);
                            }
                            catch (Exception e)
                            {

                            }
                        }
                    }
                }
            }
            return tempInput;
        }

        private string getHtmlSourceCode(string htmlPath)
        {
            string htmlText = string.Empty;

            if (htmlPath.Contains("http://") || htmlPath.Contains("https://"))
            {
                HtmlAgilityPack.HtmlWeb web = new HtmlAgilityPack.HtmlWeb();
                HtmlAgilityPack.HtmlDocument html = web.Load(htmlPath);
                html.OptionOutputAsXml = true;
                htmlText = html.DocumentNode.InnerHtml;
            }
            else
            {
                using (var htmlStream = System.IO.File.OpenText(htmlPath))
                {
                    htmlText = htmlStream.ReadToEnd();
                    htmlStream.Close();
                }
            }

            return htmlText;
        }

        private string getCssSourceCode(string cssPath)
        {
            string cssText = string.Empty;

            if (!string.IsNullOrEmpty(cssPath))
            {
                using (var cssStream = System.IO.File.OpenText(cssPath))
                {
                    cssText = cssStream.ReadToEnd();
                    cssStream.Close();
                }
            }

            return cssText;
        }

        #endregion

        #region Public Methods

        public void CreatePDF(string htmlFilePath, string pdfFilePath, string cssFilePath)
        {
            byte[] pdf = new byte[0];

            if (!string.IsNullOrEmpty(pdfFilePath))
            {
                pdf = CreatePDF(htmlFilePath, cssFilePath);

                using (var pdfStream = new System.IO.FileStream(pdfFilePath, System.IO.FileMode.OpenOrCreate))
                {
                    pdfStream.Write(pdf, 0, pdf.Length);
                    pdfStream.Close();
                }
            }
        }

        public byte[] CreatePDF(string htmlFilePath, string cssFilePath)
        {
            if (string.IsNullOrEmpty(htmlFilePath)) return new byte[0];

            byte[] pdf = new byte[0];
            string htmlText = getHtmlSourceCode(htmlFilePath);
            string cssText = getCssSourceCode(cssFilePath);

            if (!string.IsNullOrEmpty(htmlText))
            {
                htmlText = getImage(htmlText);

                System.IO.MemoryStream msHtml = new System.IO.MemoryStream(System.Text.Encoding.UTF8.GetBytes(htmlText));
                System.IO.MemoryStream msCss = new System.IO.MemoryStream(System.Text.Encoding.UTF8.GetBytes(cssText));

                using (var pdfStream = new System.IO.MemoryStream())
                {
                    using (iTextSharp.text.Document doc = new iTextSharp.text.Document(this.rectangle))
                    {
                        using (var pdfWriter = iTextSharp.text.pdf.PdfWriter.GetInstance(doc, pdfStream))
                        {
                            doc.Open();

                            if (msCss.Length == 0)
                            {
                                iTextSharp.tool.xml.XMLWorkerHelper.GetInstance().ParseXHtml(pdfWriter, doc, msHtml, System.Text.Encoding.UTF8);
                            }
                            else
                            {
                                iTextSharp.tool.xml.XMLWorkerHelper.GetInstance().ParseXHtml(pdfWriter, doc, msHtml, msCss, System.Text.Encoding.UTF8);
                            }

                            doc.Close();
                            pdfWriter.Close();
                        }
                    }

                    pdf = pdfStream.ToArray();
                }
            }

            return pdf;
        }

        #endregion
    }
}