#if !NET8
using iTextSharp.text;
using iTextSharp.text.html.simpleparser;
using iTextSharp.text.pdf;
#endif

using System.IO;

namespace Fab2ApprovalSystem.PdfGenerator;

/// <summary>
/// This class is responsible for rendering a html text string to a PDF document using the html renderer of iTextSharp.
/// </summary>
public class StandardPdfRenderer {
    private const int HorizontalMargin = 40;
    private const int VerticalMargin = 40;

    public byte[] Render(string htmlText, string pageTitle) {
        byte[] renderedBuffer;

        using (MemoryStream outputMemoryStream = new()) {
#if !NET8
            using (Document pdfDocument = new Document(PageSize.A4, HorizontalMargin, HorizontalMargin, VerticalMargin, VerticalMargin)) {
                PdfWriter pdfWriter = PdfWriter.GetInstance(pdfDocument, outputMemoryStream);
                pdfWriter.CloseStream = false;
                pdfWriter.PageEvent = new PrintHeaderFooter { Title = pageTitle };
                pdfDocument.Open();
                using (StringReader htmlViewReader = new StringReader(htmlText)) {
                    using (HTMLWorker htmlWorker = new HTMLWorker(pdfDocument)) {
                        htmlWorker.Parse(htmlViewReader);
                    }
                }

            }
#endif

            renderedBuffer = new byte[outputMemoryStream.Position];
            outputMemoryStream.Position = 0;
            outputMemoryStream.Read(renderedBuffer, 0, renderedBuffer.Length);
        }

        return renderedBuffer;
    }
}