Correctly preserved the graphic state & some xml comments

Author: synercoder

src/Synercoding.FileFormats.Pdf/Extensions/IContentContextExtensions.cs

@@ -2,12 +2,30 @@
 using System.Threading.Tasks;
 
 namespace Synercoding.FileFormats.Pdf.Extensions;
+
+/// <summary>
+/// Extension class for <see cref="IContentContext{TSelf}"/>
+/// </summary>
 public static class IContentContextExtensions
 {
+    /// <summary>
+    /// Wraps the operations in <paramref name="contentOperations"/> in save state and restore state operators.
+    /// </summary>
+    /// <typeparam name="TContext">The context type where this extension applies to.</typeparam>
+    /// <param name="context">The content context where that will be wrapped.</param>
+    /// <param name="contentOperations">The operations to be wrapped.</param>
+    /// <returns>The same <typeparamref name="TContext"/> to enable method chaining.</returns>
     public static TContext WrapInState<TContext>(this TContext context, Action<TContext> contentOperations)
         where TContext : IContentContext<TContext>
         => context.WrapInState(contentOperations, static (operations, context) => operations(context));
 
+    /// <summary>
+    /// Wraps the operations in <paramref name="contentOperations"/> in save state and restore state operators.
+    /// </summary>
+    /// <typeparam name="TContext">The context type where this extension applies to.</typeparam>
+    /// <param name="context">The content context where that will be wrapped.</param>
+    /// <param name="contentOperations">The async operations to be wrapped.</param>
+    /// <returns>Task that resolves to the same <typeparamref name="TContext"/> to enable method chaining.</returns>
     public static Task<TContext> WrapInStateAsync<TContext>(this TContext context, Func<TContext, Task> contentOperations)
         where TContext : IContentContext<TContext>
         => context.WrapInStateAsync(contentOperations, static (operations, context) => operations(context));

src/Synercoding.FileFormats.Pdf/Extensions/IPageContentContextExtensions.cs

@@ -71,10 +71,10 @@ public static IPageContentContext AddImage(this IPageContentContext context, Ima
         });
     }
 
-    public static IPageContentContext AddShapes(this IPageContentContext context, Action<IShapeContext> shapeOperations)
+    public static IPageContentContext AddShapes(this IPageContentContext context, Action<IShapeContentContext> shapeOperations)
         => context.AddShapes(shapeOperations, static (operations, context) => operations(context));
 
-    public static Task<IPageContentContext> AddShapesAsync(this IPageContentContext context, Func<IShapeContext, Task> shapeOperations)
+    public static Task<IPageContentContext> AddShapesAsync(this IPageContentContext context, Func<IShapeContentContext, Task> shapeOperations)
         => context.AddShapesAsync(shapeOperations, static (operations, context) => operations(context));
 
     public static IPageContentContext AddText(this IPageContentContext context, Action<ITextContentContext> textOperations)
@@ -104,7 +104,7 @@ public static IPageContentContext AddText<T>(this IPageContentContext context, s
             var lines = StringHelper.SplitOnNewLines(text).ToArray();
 
             // if no leading parameter is set, and the text spans multiple lines, set textleading to the font size.
-            if (lines.Length > 1 && context.TextLeading == default)
+            if (lines.Length > 1 && context.GraphicState.TextLeading == default)
                 context.SetTextLeading(size);
 
             for (int i = 0; i < lines.Length; i++)

src/Synercoding.FileFormats.Pdf/Extensions/IShapeContextExtensions.cs

@@ -4,6 +4,6 @@
 namespace Synercoding.FileFormats.Pdf.Extensions;
 public static class IShapeContextExtensions
 {
-    public static IShapeContext Rectangle(this IShapeContext context, Rectangle rectangle)
+    public static IShapeContentContext Rectangle(this IShapeContentContext context, Rectangle rectangle)
         => context.Rectangle(rectangle.LLX.AsRaw(Unit.Points), rectangle.LLY.AsRaw(Unit.Points), rectangle.Width.AsRaw(Unit.Points), rectangle.Height.AsRaw(Unit.Points));
 }

src/Synercoding.FileFormats.Pdf/GraphicState.cs

@@ -0,0 +1,70 @@
+using Synercoding.FileFormats.Pdf.LowLevel.Colors;
+using Synercoding.FileFormats.Pdf.LowLevel.Graphics;
+using Synercoding.FileFormats.Pdf.LowLevel.Text;
+using System.Linq;
+
+namespace Synercoding.FileFormats.Pdf;
+
+public sealed class GraphicState
+{
+    internal GraphicState()
+    {
+        CTM = Matrix.Identity;
+        FillColor = PredefinedColors.Black;
+        StrokeColor = PredefinedColors.Black;
+        LineWidth = 1.0;
+        LineCap = LineCapStyle.ButtCap;
+        LineJoin = LineJoinStyle.MiterJoin;
+        MiterLimit = 10.0;
+        DashPattern = new Dash();
+        CharacterSpacing = 0.0;
+        WordSpacing = 0.0;
+        HorizontalScaling = 100.0;
+        TextLeading = 0.0;
+        Font = null;
+        FontSize = null;
+        TextRenderingMode = TextRenderingMode.Fill;
+        TextRise = 0.0;
+    }
+
+    public Matrix CTM { get; internal set; } 
+    public Color FillColor { get; internal set; } 
+    public Color StrokeColor { get; internal set; } 
+    public double LineWidth { get; internal set; } 
+    public LineCapStyle LineCap { get; internal set; } 
+    public LineJoinStyle LineJoin { get; internal set; }
+    public double MiterLimit { get; internal set; }
+    public Dash DashPattern { get; internal set; } 
+    public double CharacterSpacing { get; internal set; } 
+    public double WordSpacing { get; internal set; } 
+    public double HorizontalScaling { get; internal set; }
+    public double TextLeading { get; internal set; }
+    public Font? Font { get; internal set; }
+    public double? FontSize { get; internal set; }
+    public TextRenderingMode TextRenderingMode { get; internal set; }
+    public double TextRise { get; internal set; }
+
+    internal GraphicState Clone()
+    {
+        return new GraphicState()
+        {
+            CTM = CTM,
+            FillColor = FillColor,
+            StrokeColor = StrokeColor,
+            LineWidth = LineWidth,
+            LineCap = LineCap,
+            LineJoin = LineJoin,
+            MiterLimit = MiterLimit,
+            DashPattern = new Dash(DashPattern.Array.ToArray(), DashPattern.Phase),
+            CharacterSpacing = CharacterSpacing,
+            WordSpacing = WordSpacing,
+            HorizontalScaling = HorizontalScaling,
+            TextLeading = TextLeading,
+            Font = Font,
+            FontSize = FontSize,
+            TextRenderingMode = TextRenderingMode,
+            TextRise = TextRise
+        };
+    }
+}
+

src/Synercoding.FileFormats.Pdf/IContentContext.cs

@@ -11,19 +11,12 @@ public interface IContentContext<TSelf>
 {
     ContentStream RawContentStream { get; }
 
+    GraphicState GraphicState { get; }
+
     TSelf WrapInState<T>(T data, Action<T, TSelf> contentOperations);
 
     Task<TSelf> WrapInStateAsync<T>(T data, Func<T, TSelf, Task> contentOperations);
 
-    Matrix CTM { get; }
-    Color FillColor { get; }
-    Color StrokeColor { get; }
-    double LineWidth { get; }
-    LineCapStyle LineCap { get; }
-    LineJoinStyle LineJoin { get; }
-    double MiterLimit { get; }
-    Dash DashPattern { get; }
-
     TSelf ConcatenateMatrix(Matrix matrix);
 
     TSelf SetStroke(Color stroke);

src/Synercoding.FileFormats.Pdf/IPageContentContext.cs

@@ -10,6 +10,6 @@ public interface IPageContentContext : IContentContext<IPageContentContext>
     IPageContentContext AddText<T>(T data, Action<T, ITextContentContext> textOperations);
     Task<IPageContentContext> AddTextAsync<T>(T data, Func<T, ITextContentContext, Task> textOperations);
 
-    IPageContentContext AddShapes<T>(T data, Action<T, IShapeContext> shapeOperations);
-    Task<IPageContentContext> AddShapesAsync<T>(T data, Func<T, IShapeContext, Task> shapeOperations);
+    IPageContentContext AddShapes<T>(T data, Action<T, IShapeContentContext> shapeOperations);
+    Task<IPageContentContext> AddShapesAsync<T>(T data, Func<T, IShapeContentContext, Task> shapeOperations);
 }

src/Synercoding.FileFormats.Pdf/IShapeContext.cs renamed to src/Synercoding.FileFormats.Pdf/IShapeContentContext.cs

@@ -2,25 +2,28 @@
 
 namespace Synercoding.FileFormats.Pdf;
 
-public interface IShapeContext : IContentContext<IShapeContext>
+/// <summary>
+/// Context to enable shape operations on the content
+/// </summary>
+public interface IShapeContentContext : IContentContext<IShapeContentContext>
 {
     /// <summary>
     /// Begin a new subpath by moving the current point to the coordinates (<paramref name="x"/>, <paramref name="y"/>),
     /// omitting any connecting line segment. Appends an (m) operator to the content stream
     /// </summary>
     /// <param name="x">The X coordinate of the move</param>
     /// <param name="y">The Y coordinate of the move</param>
-    /// <returns>The calling <see cref="IShapeContext"/> to support chaining operations.</returns>
-    IShapeContext Move(double x, double y);
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext Move(double x, double y);
 
 
     /// <summary>
     /// Add a line (l) operator to the content stream
     /// </summary>
     /// <param name="x">The X coordinate of the line end point</param>
     /// <param name="y">The Y coordinate of the line end point</param>
-    /// <returns>The calling <see cref="IShapeContext"/> to support chaining operations.</returns>
-    IShapeContext LineTo(double x, double y);
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext LineTo(double x, double y);
 
     /// <summary>
     /// Add a rectangle (re) operator to the content stream
@@ -29,8 +32,8 @@ public interface IShapeContext : IContentContext<IShapeContext>
     /// <param name="y">The Y coordinate of the rectangle</param>
     /// <param name="width">The width of the rectangle</param>
     /// <param name="height">The height of the rectangle</param>
-    /// <returns>The calling <see cref="IShapeContext"/> to support chaining operations.</returns>
-    IShapeContext Rectangle(double x, double y, double width, double height);
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext Rectangle(double x, double y, double width, double height);
 
     /// <summary>
     /// Append a cubic Bézier curve to the current path. The curve shall extend from the current point to the point (<paramref name="finalX"/>, <paramref name="finalY"/>),
@@ -43,8 +46,8 @@ public interface IShapeContext : IContentContext<IShapeContext>
     /// <param name="cpY2">The Y coordinate of the second control point</param>
     /// <param name="finalX">The X coordinate of the endpoint of the curve</param>
     /// <param name="finalY">The Y coordinate of the endpoint of the curve</param>
-    /// <returns>The calling <see cref="IShapeContext"/> to support chaining operations.</returns>
-    IShapeContext CurveTo(double cpX1, double cpY1, double cpX2, double cpY2, double finalX, double finalY);
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext CurveTo(double cpX1, double cpY1, double cpX2, double cpY2, double finalX, double finalY);
 
     /// <summary>
     /// Append a cubic Bézier curve to the current path. The curve shall extend from the current point to the point (<paramref name="finalX"/>, <paramref name="finalY"/>),
@@ -55,8 +58,8 @@ public interface IShapeContext : IContentContext<IShapeContext>
     /// <param name="cpY2">The Y coordinate of the second control point</param>
     /// <param name="finalX">The X coordinate of the endpoint of the curve</param>
     /// <param name="finalY">The Y coordinate of the endpoint of the curve</param>
-    /// <returns>The calling <see cref="IShapeContext"/> to support chaining operations.</returns>
-    IShapeContext CurveToWithStartAnker(double cpX2, double cpY2, double finalX, double finalY);
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext CurveToWithStartAnker(double cpX2, double cpY2, double finalX, double finalY);
 
     /// <summary>
     /// Append a cubic Bézier curve to the current path. The curve shall extend from the current point to the point (<paramref name="finalX"/>, <paramref name="finalY"/>),
@@ -67,39 +70,59 @@ public interface IShapeContext : IContentContext<IShapeContext>
     /// <param name="cpY1">The Y coordinate of the first control point</param>
     /// <param name="finalX">The X coordinate of the endpoint of the curve</param>
     /// <param name="finalY">The Y coordinate of the endpoint of the curve</param>
-    /// <returns>The calling <see cref="IShapeContext"/> to support chaining operations.</returns>
-    IShapeContext CurveToWithEndAnker(double cpX1, double cpY1, double finalX, double finalY);
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext CurveToWithEndAnker(double cpX1, double cpY1, double finalX, double finalY);
 
     /// <summary>
-    /// Close the active subpath in this <see cref="IShapeContext"/>
+    /// Close the active subpath in this <see cref="IShapeContentContext"/>
     /// </summary>
-    IShapeContext CloseSubPath();
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext CloseSubPath();
 
     /// <summary>
-    /// 
+    /// Mark the current path to be used as a clipping mask.
     /// </summary>
-    /// <param name="fillRule"></param>
-    /// <returns></returns>
-    IShapeContext MarkPathForClipping(FillRule fillRule);
+    /// <param name="fillRule">The <see cref="FillRule"/> to use</param>
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext MarkPathForClipping(FillRule fillRule);
 
-    IShapeContext Stroke();
+    /// <summary>
+    /// Stroke the current path
+    /// </summary>
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext Stroke();
 
     /// <summary>
     /// Close and stroke the path. 
     /// </summary>
     /// <remarks>This operator has the same effect as the sequence <see cref="CloseSubPath"/>() and then <see cref="Stroke"/>().</remarks>
-    /// <returns></returns>
-    IShapeContext CloseSubPathAndStroke();
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext CloseSubPathAndStroke();
 
-    IShapeContext Fill(FillRule fillRule);
+    /// <summary>
+    /// Fill the current path using <paramref name="fillRule"/> as the fill rule.
+    /// </summary>
+    /// <param name="fillRule">The <see cref="FillRule"/> to use</param>
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext Fill(FillRule fillRule);
 
-    IShapeContext FillThenStroke(FillRule fillRule);
+    /// <summary>
+    /// Fill the current path using <paramref name="fillRule"/> as the fill rule, and then stroke the path.
+    /// </summary>
+    /// <param name="fillRule">The <see cref="FillRule"/> to use</param>
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext FillThenStroke(FillRule fillRule);
 
-    IShapeContext CloseSubPathFillStroke(FillRule fillRule);
+    /// <summary>
+    /// Close the current path, then fill the current path using <paramref name="fillRule"/> as the fill rule, and then stroke the path.
+    /// </summary>
+    /// <param name="fillRule">The <see cref="FillRule"/> to use</param>
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext CloseSubPathFillStroke(FillRule fillRule);
 
     /// <summary>
     /// End the path object without filling or stroking it. This operator is a path-painting no-op, used primarily for the side effect of changing the current clipping path.
     /// </summary>
-    /// <returns>The calling <see cref="IShapeContext"/> to support chaining operations.</returns>
-    IShapeContext EndPathNoStrokeNoFill();
+    /// <returns>The calling <see cref="IShapeContentContext"/> to support chaining operations.</returns>
+    IShapeContentContext EndPathNoStrokeNoFill();
 }

src/Synercoding.FileFormats.Pdf/ITextContentContext.cs

@@ -1,18 +1,9 @@
-using Synercoding.FileFormats.Pdf.LowLevel.Text;
+using Synercoding.FileFormats.Pdf.LowLevel.Text;
 
 namespace Synercoding.FileFormats.Pdf;
 
 public interface ITextContentContext : IContentContext<ITextContentContext>
 {
-    double CharacterSpacing { get; }
-    double WordSpacing { get; }
-    double HorizontalScaling { get; }
-    double TextLeading { get; }
-    Font? Font { get; }
-    double? FontSize { get; }
-    TextRenderingMode TextRenderingMode { get; }
-    double TextRise { get; }
-
     ITextContentContext SetCharacterSpacing(double spacing);
     ITextContentContext SetWordSpacing(double spacing);
     ITextContentContext SetHorizontalScaling(double scaling);

src/Synercoding.FileFormats.Pdf/Image.cs

@@ -78,8 +78,14 @@ internal Image(PdfReference id, Stream jpgStream, int width, int height, PdfName
     /// </summary>
     public int Height { get; }
 
+    /// <summary>
+    /// The name of the colorspace used in this <see cref="Image"/>
+    /// </summary>
     public PdfName ColorSpace { get; }
 
+    /// <summary>
+    /// The decode array used in this <see cref="Image"/>
+    /// </summary>
     public double[] DecodeArray { get; }
 
     /// <inheritdoc />