refactor: standardize annotation types and clean up PDF burn handler

- Introduced `AnnotationType.PSPDFKit` constants for consistent annotation type references.
- Updated `BurnPdfCommandHandler` to use new PSPDFKit annotation types.
- Refactored method signatures and local variables for clarity (e.g., using 'var', null-coalescing for annotation properties).
- Streamlined `using` statements and memory management in PDF burning process.
- Added placeholder methods for form fields, image, and ink annotations to centralize future implementations.

EnvelopeGenerator.Application/Pdf/BurnPdfCommand.cs

@@ -1,6 +1,7 @@
 using DigitalData.Core.Abstraction.Application.Repository;
 using EnvelopeGenerator.Application.Common.Configurations;
 using EnvelopeGenerator.Application.Exceptions;
+using EnvelopeGenerator.Domain.Constants;
 using EnvelopeGenerator.Domain.Entities;
 using EnvelopeGenerator.PdfEditor;
 using GdPicture14;
@@ -72,93 +73,86 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand>
     public byte[] BurnElementAnnotsToPDF(byte[] pSourceBuffer, List<Signature> elements)
     {
         // Add background
-        using (var doc = PdfEditor.Pdf.FromMemory(pSourceBuffer))
+        using var doc = PdfEditor.Pdf.FromMemory(pSourceBuffer);
+        // TODO: take the length from the largest y
+        pSourceBuffer = doc.Background(elements, 1.9500000000000002 * 0.93, 2.52 * 0.67)
+                        .ExportStream()
+                        .ToArray();
+
+        GdPictureStatus oResult;
+        using var oSourceStream = new MemoryStream(pSourceBuffer);
+        // Open PDF
+        oResult = _manager.InitFromStream(oSourceStream);
+        if (oResult != GdPictureStatus.OK)
+            throw new BurnAnnotationException($"Could not open document for burning: [{oResult}]");
+
+        // Imported from background (add to configuration)
+        var margin = 0.2;
+        var inchFactor = 72;
+
+        // Y offset of form fields
+        var keys = new[] { "position", "city", "date" }; // add to configuration
+        var unitYOffsets = 0.2;
+
+        var yOffsetsOfFF = keys
+            .Select((k, i) => new { Key = k, Value = unitYOffsets * i + 1 })
+            .ToDictionary(x => x.Key, x => x.Value);
+
+        // Add annotations
+        foreach (var element in elements)
         {
-            // TODO: take the length from the largest y
+            var frameX = element.Left - 0.7 - margin;
-            pSourceBuffer = doc.Background(elements, 1.9500000000000002 * 0.93, 2.52 * 0.67)
-                            .ExportStream()
-                            .ToArray();
 
-            GdPictureStatus oResult;
+            var frame = element.Annotations?.FirstOrDefault(a => a.Name == "frame");
-            using (var oSourceStream = new MemoryStream(pSourceBuffer))
+            var frameY = element.Top - 0.5 - margin;
+            var frameYShift = (frame!.Y ?? default) - frameY * inchFactor;
+            var frameXShift = (frame.X ?? default) - frameX * inchFactor;
+
+            foreach (var annot in element.Annotations!)
             {
-                // Open PDF
+                if (!yOffsetsOfFF.TryGetValue(annot.Name, out var yOffsetofFF))
-                oResult = _manager.InitFromStream(oSourceStream);
+                    yOffsetofFF = 0;
-                if (oResult != GdPictureStatus.OK)
-                    throw new BurnAnnotationException($"Could not open document for burning: [{oResult}]");
 
-                // Imported from background (add to configuration)
+                var y = frameY + yOffsetofFF;
-                double margin = 0.2;
-                double inchFactor = 72;
 
-                // Y offset of form fields
+                if (annot.Type == AnnotationType.PSPDFKit.FormField)
-                var keys = new[] { "position", "city", "date" }; // add to configuration
-                double unitYOffsets = 0.2;
-
-                var yOffsetsOfFF = keys
-                    .Select((k, i) => new { Key = k, Value = unitYOffsets * i + 1 })
-                    .ToDictionary(x => x.Key, x => x.Value);
-
-                // Add annotations
-                foreach (var element in elements)
                 {
-                    double frameX = element.Left - 0.7 - margin;
+                    AddFormFieldValue(
-
+                        (annot.X ?? default) / inchFactor,
-                    var frame = element.Annotations?.FirstOrDefault(a => a.Name == "frame");
+                        y,
-                    double frameY = element.Top - 0.5 - margin;
+                        (annot.Width ?? default) / inchFactor,
-                    double frameYShift = (frame!.Y ?? default) - frameY * inchFactor;
+                        (annot.Height ?? default) / inchFactor,
-                    double frameXShift = (frame.X ?? default) - frameX * inchFactor;
+                        element.Page,
-
+                        annot.Value
-                    foreach (var annot in element.Annotations!)
+                    );
-                    {
-                        double yOffsetofFF;
-                        if (!yOffsetsOfFF.TryGetValue(annot.Name, out yOffsetofFF))
-                            yOffsetofFF = 0;
-
-                        double y = frameY + yOffsetofFF;
-
-                        if (annot.Type == AnnotationType.FormField)
-                        {
-                            AddFormFieldValue(
-                                annot.X / inchFactor,
-                                y,
-                                annot.Width / inchFactor,
-                                annot.Height / inchFactor,
-                                element.Page,
-                                annot.Value
-                            );
-                        }
-                        else if (annot.Type == AnnotationType.Image)
-                        {
-                            AddImageAnnotation(
-                                annot.X / inchFactor,
-                                annot.Name == "signature" ? (annot.Y - frameYShift) / inchFactor : y,
-                                annot.Width / inchFactor,
-                                annot.Height / inchFactor,
-                                element.Page,
-                                annot.Value
-                            );
-                        }
-                        else if (annot.Type == AnnotationType.Ink)
-                        {
-                            AddInkAnnotation(element.Page, annot.Value);
-                        }
-                    }
                 }
-
+                else if (annot.Type == AnnotationType.PSPDFKit.Image)
-                // Save PDF
-                using (var oNewStream = new MemoryStream())
                 {
-                    oResult = _manager.SaveDocumentToPDF(oNewStream);
+                    AddImageAnnotation(
-                    if (oResult != GdPictureStatus.OK)
+                        (annot.X ?? default) / inchFactor,
-                        throw new BurnAnnotationException($"Could not save document to stream: [{oResult}]");
+                        annot.Name == "signature" ? ((annot.Y ?? default) - frameYShift) / inchFactor : y,
-
+                        (annot.Width ?? default) / inchFactor,
-                    _manager.Close();
+                        (annot.Height ?? default) / inchFactor,
-
+                        element.Page,
-                    return oNewStream.ToArray();
+                        annot.Value
+                    );
+                }
+                else if (annot.Type == AnnotationType.PSPDFKit.Ink)
+                {
+                    AddInkAnnotation(element.Page, annot.Value);
                 }
             }
         }
+
+        // Save PDF
+        using var oNewStream = new MemoryStream();
+        oResult = _manager.SaveDocumentToPDF(oNewStream);
+        if (oResult != GdPictureStatus.OK)
+            throw new BurnAnnotationException($"Could not save document to stream: [{oResult}]");
+
+        _manager.Close();
+
+        return oNewStream.ToArray();
     }
 
     /// <summary>
@@ -169,7 +163,38 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand>
     /// <returns></returns>
     public byte[] BurnInstantJSONAnnotsToPDF(byte[] pSourceBuffer, List<string> pInstantJSONList)
     {
-        return Enumerable.Empty<byte>().ToArray();
+        throw new NotImplementedException();
+    }
+
+    private void AddFormFieldValue(double x, double y, double width, double height, int page, string value)
+    {
+        throw new NotImplementedException();
+    }
+
+
+    private void AddFormFieldValue(Annotation pAnnotation, FormFieldValue formFieldValue)
+    {
+        throw new NotImplementedException();
+    }
+
+    private void AddImageAnnotation(double x, double y, double width, double height, int page, string base64)
+    {
+        throw new NotImplementedException();
+    }
+
+    private void AddImageAnnotation(Annotation pAnnotation, Dictionary<string, Attachment> pAttachments)
+    {
+        throw new NotImplementedException();
+    }
+
+    private void AddInkAnnotation(int page, string value)
+    {
+        throw new NotImplementedException();
+    }
+
+    private void AddInkAnnotation(Annotation pAnnotation)
+    {
+        throw new NotImplementedException();
     }
 
     /// <summary>

EnvelopeGenerator.Domain/Constants/AnnotationType.cs

@@ -0,0 +1,13 @@
+namespace EnvelopeGenerator.Domain.Constants
+{
+    public static class AnnotationType
+    {
+        public static class PSPDFKit
+        {
+            public const string Image = "pspdfkit/image";
+            public const string Ink = "pspdfkit/ink";
+            public const string Widget = "pspdfkit/widget";
+            public const string FormField = "pspdfkit/form-field-value";
+        }
+    }
+}