refactor(BurnPdfCommand): extract GdPicture and math helpers into extension classes and simplify BurnPdfCommandHandler

- Refactored BurnPdfCommandHandler to use new extension methods for cleaner annotation handling.
- Introduced ITextStyle interface to generalize font styling for text annotations.
- Updated PDFBurnerParams to implement ITextStyle for consistent font settings reuse.
- Added MathematExtensions for coordinate and unit conversion (ToInches, ToPointF).
- Added GdPictureExtensions to encapsulate annotation-related logic (form fields, images, ink).
- Improved readability and maintainability by removing redundant helper methods.

EnvelopeGenerator.Application/Common/Configurations/PDFBurnerParams.cs

@@ -1,4 +1,5 @@
-using System.Diagnostics.CodeAnalysis;
+using EnvelopeGenerator.Application.Common.Interfaces.Model;
+using System.Diagnostics.CodeAnalysis;
 using System.Drawing;
 
 namespace EnvelopeGenerator.Application.Common.Configurations;
@@ -6,7 +7,7 @@ namespace EnvelopeGenerator.Application.Common.Configurations;
 /// <summary>
 /// 
 /// </summary>
-public class PDFBurnerParams
+public class PDFBurnerParams : ITextStyle
 {
     /// <summary>
     /// 

EnvelopeGenerator.Application/Common/Extensions/GdPictureExtensions.cs

@@ -0,0 +1,176 @@
+using EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+using EnvelopeGenerator.Domain.Constants;
+using GdPicture14;
+using Microsoft.Extensions.Logging;
+using Newtonsoft.Json;
+using SixLabors.ImageSharp;
+using System.Drawing;
+using EnvelopeGenerator.Application.Common.Extensions;
+using EnvelopeGenerator.Application.Common.Interfaces.Model;
+using EnvelopeGenerator.Application.Common.Configurations;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class GdPictureExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="x"></param>
+    /// <param name="y"></param>
+    /// <param name="width"></param>
+    /// <param name="height"></param>
+    /// <param name="page"></param>
+    /// <param name="value"></param>
+    /// <param name="textStyle"></param>
+    public static void AddFormFieldValue(this AnnotationManager manager, double x, double y, double width, double height, int page, string value, ITextStyle textStyle)
+    {
+        manager.SelectPage(page);
+
+        // Add the text annotation
+        var ant = manager.AddTextAnnot((float)x, (float)y, (float)width, (float)height, value);
+
+        // Set the font properties
+        ant.FontName = textStyle.FontName;
+        ant.FontSize = textStyle.FontSize;
+        ant.FontStyle = textStyle.FontStyle;
+
+        manager.SaveAnnotationsToPage();
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="pAnnotation"></param>
+    /// <param name="formFieldValue"></param>
+    /// <param name="options"></param>
+    public static void AddFormFieldValue(this AnnotationManager manager, Annotation pAnnotation, FormFieldValue formFieldValue, PDFBurnerParams options)
+    {
+        var ffIndex = options.GetAnnotationIndex(pAnnotation.EgName);
+
+        // Convert pixels to Inches
+        var oBounds = pAnnotation.Bbox?.Select(points => points.ToInches()).ToList();
+
+        if (oBounds is null || oBounds.Count < 4)
+            return;
+
+        double oX = oBounds[0];
+        double oY = oBounds[1] + options.YOffset * ffIndex + options.TopMargin;
+        double oWidth = oBounds[2];
+        double oHeight = oBounds[3];
+
+        manager.SelectPage(pAnnotation.PageIndex + 1);
+
+        // Add the text annotation
+        var ant = manager.AddTextAnnot((float)oX, (float)oY, (float)oWidth, (float)oHeight, formFieldValue.Value);
+
+        // Set the font properties
+        ant.FontName = options.FontName;
+        ant.FontSize = options.FontSize;
+        ant.FontStyle = options.FontStyle;
+
+        manager.SaveAnnotationsToPage();
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="x"></param>
+    /// <param name="y"></param>
+    /// <param name="width"></param>
+    /// <param name="height"></param>
+    /// <param name="page"></param>
+    /// <param name="base64"></param>
+    public static void AddImageAnnotation(this AnnotationManager manager, double x, double y, double width, double height, int page, string base64)
+    {
+        manager.SelectPage(page);
+        manager.AddEmbeddedImageAnnotFromBase64(base64, (float)x, (float)y, (float)width, (float)height);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="pAnnotation"></param>
+    /// <param name="pAttachments"></param>
+    public static void AddImageAnnotation(this AnnotationManager manager, Annotation pAnnotation, Dictionary<string, Attachment> pAttachments)
+    {
+        var oAttachment = pAttachments
+            .Where(a => a.Key == pAnnotation.ImageAttachmentId)
+            .SingleOrDefault();
+
+        if (oAttachment.Value == null)
+            return;
+
+        // Convert pixels to Inches
+        var oBounds = pAnnotation.Bbox?.Select(post => post.ToInches()).ToList();
+
+        if (oBounds is null || oBounds.Count < 4)
+            return;
+
+        var oX = oBounds[0];
+        var oY = oBounds[1];
+        var oWidth = oBounds[2];
+        var oHeight = oBounds[3];
+
+        manager.SelectPage(pAnnotation.PageIndex + 1);
+        manager.AddEmbeddedImageAnnotFromBase64(oAttachment.Value.Binary, (float)oX, (float)oY, (float)oWidth, (float)oHeight);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="page"></param>
+    /// <param name="value"></param>
+    public static void AddInkAnnotation(this AnnotationManager manager, int page, string value)
+    {
+        var ink = JsonConvert.DeserializeObject<Ink>(value);
+
+        var oSegments = ink?.Lines.Points;
+        var oColor = ColorTranslator.FromHtml(ink?.StrokeColor ?? "#000000");
+        manager.SelectPage(page);
+
+        if (oSegments is null)
+            return;
+
+        foreach (var oSegment in oSegments)
+        {
+            var oPoints = oSegment
+                .Select(points => points.ToPointF())
+                .ToArray();
+
+            manager.AddFreeHandAnnot(oColor, oPoints);
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="pAnnotation"></param>
+    public static void AddInkAnnotation(this AnnotationManager manager, Annotation pAnnotation)
+    {
+        var oSegments = pAnnotation.Lines?.Points;
+        var oColor = ColorTranslator.FromHtml(pAnnotation.StrokeColor ?? "#000000");
+        manager.SelectPage(pAnnotation.PageIndex + 1);
+
+        if (oSegments is null)
+            return;
+
+        foreach (var oSegment in oSegments)
+        {
+            var oPoints = oSegment
+                .Select(points => points.ToPointF())
+                .ToArray();
+
+            manager.AddFreeHandAnnot(oColor, oPoints);
+        }
+    }
+}

EnvelopeGenerator.Application/Common/Extensions/MathematExtensions.cs

@@ -0,0 +1,40 @@
+using System.Drawing;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class MathematExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="points"></param>
+    /// <returns></returns>
+    public static PointF ToPointF(this List<float> points)
+    {
+        var pointsInch = points.Select(ToInches).ToList();
+        return new PointF(pointsInch[0], pointsInch[1]);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="value"></param>
+    /// <returns></returns>
+    public static double ToInches(this double value)
+    {
+        return value / 72.0;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="value"></param>
+    /// <returns></returns>
+    public static float ToInches(this float value)
+    {
+        return value / 72f;
+    }
+}

EnvelopeGenerator.Application/Common/Interfaces/Model/ITextStyle.cs

@@ -0,0 +1,27 @@
+using System.Diagnostics.CodeAnalysis;
+using System.Drawing;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Model;
+
+/// <summary>
+/// 
+/// </summary>
+public interface ITextStyle
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public string FontName { get; set; }
+
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int FontSize { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    [SuppressMessage("Interoperability", "CA1416:Validate platform compatibility", Justification = "<Pending>")]
+    public FontStyle FontStyle { get; set; }
+}

EnvelopeGenerator.Application/Pdf/BurnPdfCommand.cs

@@ -10,7 +10,7 @@ using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
-using System.Drawing;
+using EnvelopeGenerator.Application.Common.Extensions;
 
 namespace EnvelopeGenerator.Application.Pdf;
 
@@ -24,10 +24,7 @@ public record BurnPdfCommand(byte[] SourceBuffer, List<string> InstantJSONList,
 /// </summary>
 public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand, byte[]>
 {
-    /// <summary>
+    private readonly PDFBurnerParams _options;
-    /// 
-    /// </summary>
-    private readonly PDFBurnerParams _pdfBurnerParams;
 
     private readonly AnnotationManager _manager;
 
@@ -44,19 +41,13 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand, byte[]>
     /// <param name="logger"></param>
     public BurnPdfCommandHandler(IOptions<PDFBurnerParams> pdfBurnerParams, AnnotationManager manager, IRepository<Signature> signRepo, ILogger<BurnPdfCommandHandler> logger)
     {
-        _pdfBurnerParams = pdfBurnerParams.Value;
+        _options = pdfBurnerParams.Value;
         _manager = manager;
         _signRepo = signRepo;
         _logger = logger;
     }
 
-    /// <summary>
+    private byte[] BurnElementAnnotsToPDF(byte[] pSourceBuffer, List<Signature> elements)
-    /// 
-    /// </summary>
-    /// <param name="pSourceBuffer"></param>
-    /// <param name="elements"></param>
-    /// <returns></returns>
-    public byte[] BurnElementAnnotsToPDF(byte[] pSourceBuffer, List<Signature> elements)
     {
         // Add background
         using var doc = PdfEditor.Pdf.FromMemory(pSourceBuffer);
@@ -103,18 +94,19 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand, byte[]>
 
                 if (annot.Type == AnnotationType.PSPDFKit.FormField)
                 {
-                    AddFormFieldValue(
+                    _manager.AddFormFieldValue(
                         (annot.X ?? default) / inchFactor,
                         y,
                         (annot.Width ?? default) / inchFactor,
                         (annot.Height ?? default) / inchFactor,
                         element.Page,
-                        annot.Value
+                        annot.Value,
+                        _options
                     );
                 }
                 else if (annot.Type == AnnotationType.PSPDFKit.Image)
                 {
-                    AddImageAnnotation(
+                    _manager.AddImageAnnotation(
                         (annot.X ?? default) / inchFactor,
                         annot.Name == "signature" ? ((annot.Y ?? default) - frameYShift) / inchFactor : y,
                         (annot.Width ?? default) / inchFactor,
@@ -125,7 +117,7 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand, byte[]>
                 }
                 else if (annot.Type == AnnotationType.PSPDFKit.Ink)
                 {
-                    AddInkAnnotation(element.Page, annot.Value);
+                    _manager.AddInkAnnotation(element.Page, annot.Value);
                 }
             }
         }
@@ -141,13 +133,7 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand, byte[]>
         return oNewStream.ToArray();
     }
 
-    /// <summary>
+    private byte[] BurnInstantJSONAnnotsToPDF(byte[] pSourceBuffer, List<string> pInstantJSONList)
-    /// 
-    /// </summary>
-    /// <param name="pSourceBuffer"></param>
-    /// <param name="pInstantJSONList"></param>
-    /// <returns></returns>
-    public byte[] BurnInstantJSONAnnotsToPDF(byte[] pSourceBuffer, List<string> pInstantJSONList)
     {
         GdPictureStatus oResult;
 
@@ -211,11 +197,11 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand, byte[]>
             {
                 case AnnotationType.PSPDFKit.Image:
                     if (annotationData?.Attachments is not null)
-                        AddImageAnnotation(annotation, annotationData.Attachments);
+                        _manager.AddImageAnnotation(annotation, annotationData.Attachments);
                     break;
 
                 case AnnotationType.PSPDFKit.Ink:
-                    AddInkAnnotation(annotation);
+                    _manager.AddInkAnnotation(annotation);
                     break;
 
                 case AnnotationType.PSPDFKit.Widget:
@@ -223,146 +209,15 @@ public class BurnPdfCommandHandler : IRequestHandler<BurnPdfCommand, byte[]>
                     var formFieldValue = annotationData?.FormFieldValues?
                         .FirstOrDefault(fv => fv.Name == annotation.Id);
 
-                    if (formFieldValue != null && !_pdfBurnerParams.IgnoredLabels.Contains(formFieldValue.Value))
+                    if (formFieldValue != null && !_options.IgnoredLabels.Contains(formFieldValue.Value))
                     {
-                        AddFormFieldValue(annotation, formFieldValue);
+                        _manager.AddFormFieldValue(annotation, formFieldValue, _options);
                     }
                     break;
             }
         }
     }
 
-    private void AddFormFieldValue(double x, double y, double width, double height, int page, string value)
-    {
-        _manager.SelectPage(page);
-
-        // Add the text annotation
-        var ant = _manager.AddTextAnnot((float)x, (float)y, (float)width, (float)height, value);
-
-        // Set the font properties
-        ant.FontName = _pdfBurnerParams.FontName;
-        ant.FontSize = _pdfBurnerParams.FontSize;
-        ant.FontStyle = _pdfBurnerParams.FontStyle;
-
-        _manager.SaveAnnotationsToPage();
-    }
-
-    private void AddFormFieldValue(Annotation pAnnotation, FormFieldValue formFieldValue)
-    {
-        var ffIndex = _pdfBurnerParams.GetAnnotationIndex(pAnnotation.EgName);
-  
-        // Convert pixels to Inches
-        var oBounds = pAnnotation.Bbox?.Select(ToInches).ToList();
-
-        if (oBounds is null || oBounds.Count < 4)
-            return;
-
-        double oX = oBounds[0];
-        double oY = oBounds[1] + _pdfBurnerParams.YOffset * ffIndex + _pdfBurnerParams.TopMargin;
-        double oWidth = oBounds[2];
-        double oHeight = oBounds[3];
-
-        _manager.SelectPage(pAnnotation.PageIndex + 1);
-
-        // Add the text annotation
-        var ant = _manager.AddTextAnnot((float)oX, (float)oY, (float)oWidth, (float)oHeight, formFieldValue.Value);
-
-        // Set the font properties
-        ant.FontName = _pdfBurnerParams.FontName;
-        ant.FontSize = _pdfBurnerParams.FontSize;
-        ant.FontStyle = _pdfBurnerParams.FontStyle;
-
-        _manager.SaveAnnotationsToPage();
-    }
-
-    private void AddImageAnnotation(double x, double y, double width, double height, int page, string base64)
-    {
-        _manager.SelectPage(page);
-        _manager.AddEmbeddedImageAnnotFromBase64(base64, (float)x, (float)y, (float)width, (float)height);
-    }
-
-    private void AddImageAnnotation(Annotation pAnnotation, Dictionary<string, Attachment> pAttachments)
-    {
-        var oAttachment = pAttachments
-            .Where(a => a.Key == pAnnotation.ImageAttachmentId)
-            .SingleOrDefault();
-
-        if (oAttachment.Value == null)
-            return;
-
-        // Convert pixels to Inches
-        var oBounds = pAnnotation.Bbox?.Select(ToInches).ToList();
-
-        if (oBounds is null || oBounds.Count < 4)
-            return;
-
-        var oX = oBounds[0];
-        var oY = oBounds[1];
-        var oWidth = oBounds[2];
-        var oHeight = oBounds[3];
-
-        _manager.SelectPage(pAnnotation.PageIndex + 1);
-        _manager.AddEmbeddedImageAnnotFromBase64(oAttachment.Value.Binary, (float)oX, (float)oY, (float)oWidth, (float)oHeight);
-    }
-
-    private void AddInkAnnotation(int page, string value)
-    {
-        var ink = JsonConvert.DeserializeObject<Ink>(value);
-
-        var oSegments = ink?.Lines.Points;
-        var oColor = ColorTranslator.FromHtml(ink?.StrokeColor ?? "#000000");
-        _manager.SelectPage(page);
-
-        if (oSegments is null)
-            return;
-
-        foreach (var oSegment in oSegments)
-        {
-            var oPoints = oSegment
-                .Select(ToPointF)
-                .ToArray();
-
-            _manager.AddFreeHandAnnot(oColor, oPoints);
-        }
-    }
-
-    private void AddInkAnnotation(Annotation pAnnotation)
-    {
-        var oSegments = pAnnotation.Lines?.Points;
-        var oColor = ColorTranslator.FromHtml(pAnnotation.StrokeColor ?? "#000000");
-        _manager.SelectPage(pAnnotation.PageIndex + 1);
-
-        if (oSegments is null)
-            return;
-
-        foreach (var oSegment in oSegments)
-        {
-            var oPoints = oSegment
-                .Select(ToPointF)
-                .ToArray();
-
-            _manager.AddFreeHandAnnot(oColor, oPoints);
-        }
-    }
-
-    #region Helpers
-    private PointF ToPointF(List<float> pPoints)
-    {
-        var oPoints = pPoints.Select(ToInches).ToList();
-        return new PointF(oPoints[0], oPoints[1]);
-    }
-
-    private double ToInches(double pValue)
-    {
-        return pValue / 72.0;
-    }
-
-    private float ToInches(float pValue)
-    {
-        return pValue / 72f;
-    }
-    #endregion
-
     /// <summary>
     /// 
     /// </summary>