Allow rendering with Docnet PDF

TODO.txt

@@ -1,3 +1,32 @@
+magick "2026-01-29 — \$210 — WORK PERMIT.pdf" -background white -alpha background -alpha off -density 288 -resize 25% page-%03d.jpg
+https://github.com/dlemstra/Magick.NET/blob/main/docs/ConvertPDF.md
+https://stackoverflow.com/questions/65089839/add-an-external-pdf-page-to-pdfsharp-migradoc
+https://github.com/mephraim/ghostscriptsharp
+https://stackoverflow.com/a/71485279/3938401
+
+need a PDF viewer that works with annotations
+https://github.com/BobLd/PdfPig.Rendering.Skia/ works but quality is low for some reason, I don't know why. probably need a bug report or some option that is hidden.
+                using (var document = UglyToad.PdfPig.PdfDocument.Open(filePath, UglyToad.PdfPig.Rendering.Skia.SkiaRenderingParsingOptions.Instance))
+                {
+
+                    document.AddSkiaPageFactory(); // Same as document.AddPageFactory<SKPicture, SkiaPageFactory>() and document.AddPageFactory<PdfPageSize, PageSizeFactory>()
+
+                    for (int p = 1; p <= document.NumberOfPages; p++)
+                    {
+                        using var skBitmap = document.GetPageAsSKBitmap(p, 1);
+                        using (var fs = new FileStream(Path.Combine(convertedDir, $"{fileName}_{p}PIG.jpeg"), FileMode.Create))
+                        using (var ms = document.GetPageAsPng(p, 1, 4))
+                        {
+                            MemoryStream memoryStream = new MemoryStream();
+                            skBitmap.Encode(memoryStream, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
+                            memoryStream.Position = 0L;
+
+                            ms.WriteTo(fs);
+                        }
+                    }
+                }
+https://github.com/GowenGit/docnet -- may need to fork this and publish our own package if some OS doesn't work
+
 *-add more items
 *-save last opened folder to settings somewhere
 

src/MayShow.csproj

@@ -51,5 +51,7 @@
     <PackageReference Include="Deadpikle.AvaloniaProgressRing" Version="0.10.11-preview20251127001" />
     <PackageReference Include="DialogHost.Avalonia" Version="0.10.4" />
     <PackageReference Include="Xaml.Behaviors.Interactions.DragAndDrop.DataGrid" Version="11.3.9.5" />
+    <PackageReference Include="Docnet.Core" Version="2.6.0" />
+    <PackageReference Include="SixLabors.ImageSharp" Version="3.1.12" />
   </ItemGroup>
 </Project>

src/Models/Settings.cs

@@ -12,10 +12,12 @@ namespace MayShow.Models;
 class Settings : ChangeNotifier
 {
     private string _lastUsedPath;
+    private bool _useDocnetPDFImageRendering;
 
     public Settings()
     {
         _lastUsedPath = "";
+        _useDocnetPDFImageRendering = true;
     }
 
     [JsonInclude]
@@ -25,6 +27,13 @@ class Settings : ChangeNotifier
         set { _lastUsedPath = value; NotifyPropertyChanged(); }
     }
 
+    [JsonInclude]
+    public bool UseDocnetPFDImageRendering
+    {
+        get => _useDocnetPDFImageRendering;
+        set { _useDocnetPDFImageRendering = value; NotifyPropertyChanged(); }
+    }
+
     public static string GetSettingsFileName()
     {
         return "settings.json";

src/ViewModels/MainViewModel.cs

@@ -21,6 +21,14 @@ using MayShow.Interfaces;
 using MayShow.Models;
 using MayShows.Helpers;
 
+using Docnet.Core.Models;
+using Docnet.Core;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.PixelFormats;
+using SixLabors.ImageSharp.Processing;
+using System.Reflection.Metadata.Ecma335;
+using Docnet.Core.Readers;
+
 namespace MayShow.ViewModels;
 
 class MainViewModel : BaseViewModel, IFontResolver, ICanCheckShutdown
@@ -708,7 +716,7 @@ class MainViewModel : BaseViewModel, IFontResolver, ICanCheckShutdown
                     filePath = convertedOutputPath;
                     LogInfo(string.Format("Saved adjusted image to JPEG; file path is now {0}", filePath));                    
                 }
-            }
+                // write to PDF
                 var paragraph = section.AddParagraph();
                 paragraph.Format.Alignment = ParagraphAlignment.Center;
                 var image = paragraph.AddImage(filePath);
@@ -721,14 +729,67 @@ class MainViewModel : BaseViewModel, IFontResolver, ICanCheckShutdown
                 {
                     image.Width = imageWidth; // can't be too wide now...not sure why...maybe due to margins...
                 }
-            LogInfo(string.Format("Added image: {0} ({1})", file.Title, filePath));
+            }
-            if (isPDF)
+            else
             {
-                // add other PDF pages
+                // need to render PDF to images
+                if (_settings.UseDocnetPFDImageRendering)
+                {
+                    // render using Docnet library (which utilizes pdfium, the chrome renderer)
+                    string RenderPdfPageToImage(IDocReader docReader, int pgNum)
+                    {
+                        Console.WriteLine("rendering pg " + pgNum);
+                        using var pageReader = docReader.GetPageReader(pgNum);
+                        var rawBytes = pageReader.GetImage(RenderFlags.RenderAnnotations);
+                        var width = pageReader.GetPageWidth();
+                        var height = pageReader.GetPageHeight();
+                        using var img = Image.LoadPixelData<Bgra32>(rawBytes, width, height);
+                        // you are likely going to want this as well otherwise you might end up with transparent parts.
+                        img.Mutate(x => x.BackgroundColor(SixLabors.ImageSharp.Color.White));
+                        var pdfPageImageOutputPath = Path.Combine(convertedDir, info.Name + "-Page-" 
+                            + (pgNum + 1).ToString().PadLeft(3, '0') + ".jpg");
+                        img.Save(pdfPageImageOutputPath);
+                        return pdfPageImageOutputPath;
+                    }
+                    // render all pages to images
+                    using var docReader = DocLib.Instance.GetDocReader(
+                        filePath,
+                        new PageDimensions(1080, 1920)); // TODO: are these dims right?
+                    // add to document
+                    var pgCount = docReader.GetPageCount();
+                    if (pgCount > 0)
+                    {
+                        var convertedPdfImagePath = RenderPdfPageToImage(docReader, 0);
+                        imageTitlePar.AddText(string.Format(" (PDF with {0} page{1}) ", 
+                            pgCount, 
+                            pgCount == 1 ? "" : "s"));
+                        var paragraph = section.AddParagraph();
+                        paragraph.Format.Alignment = ParagraphAlignment.Center;
+                        var image = paragraph.AddImage(convertedPdfImagePath);
+                        for (var j = 1; j < pgCount; j++)
+                        {
+                            section.AddPageBreak();
+                            paragraph = section.AddParagraph();
+                            paragraph.Format.Alignment = ParagraphAlignment.Center;
+                            convertedPdfImagePath = RenderPdfPageToImage(docReader, j);
+                            image = paragraph.AddImage(convertedPdfImagePath);
+                            image.LockAspectRatio = true;
+                            image.Width = imageWidth;
+                        }
+                    }
+                }
+                else
+                {
+                    // render first page (eventually need to improve code to just do everything in a loop)
+                    var paragraph = section.AddParagraph();
+                    paragraph.Format.Alignment = ParagraphAlignment.Center;
+                    var image = paragraph.AddImage(filePath);
+                    image.LockAspectRatio = true;
+                    image.Width = imageWidth; // can't be too wide now...not sure why...maybe due to margins...
+                    // render other PDF pages, if any
                     // see: https://stackoverflow.com/a/65091204/3938401
                     var pdfFileToAdd = PdfReader.Open(filePath, PdfDocumentOpenMode.Import);
                     var pgCount = pdfFileToAdd.PageCount;
-                pdfFileToAdd.Close();
                     imageTitlePar.AddText(string.Format(" (PDF with {0} page{1}) ", 
                         pgCount, 
                         pgCount == 1 ? "" : "s"));
@@ -742,6 +803,8 @@ class MainViewModel : BaseViewModel, IFontResolver, ICanCheckShutdown
                         image.Width = imageWidth;
                     }
                 }
+            }
+            LogInfo(string.Format("Added image: {0} ({1})", file.Title, filePath));
             hasAddedData = true;
         }
         var pdfRenderer = new PdfDocumentRenderer