#26 add missing operation and expose the content stream directly to the user through the page

src/UglyToad.PdfPig.Tests/Parser/PageContentParserTests.cs

@@ -2,6 +2,7 @@
 {
     using System;
     using System.IO;
+    using System.Text.RegularExpressions;
     using PdfPig.Graphics;
     using PdfPig.Graphics.Core;
     using PdfPig.Graphics.Operations.General;
@@ -11,6 +12,7 @@
     using PdfPig.Graphics.Operations.TextState;
     using PdfPig.Parser;
     using PdfPig.Tokens;
+    using PdfPig.Util;
     using Xunit;
 
     public class PageContentParserTests
@@ -29,6 +31,64 @@
             Assert.NotEmpty(result);
         }
 
+        [Fact]
+        public void CorrectlyWritesOperations()
+        {
+            var path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Parser", "SimpleGoogleDocPageContent.txt");
+            var content = File.ReadAllText(path);
+            var input = StringBytesTestConverter.Convert(content, false);
+
+            var result = parser.Parse(input.Bytes);
+
+            var replacementRegex = new Regex(@"\s(\.\d+)\b");
+
+            using (var stream = new MemoryStream())
+            {
+                foreach (var operation in result)
+                {
+                    operation.Write(stream);
+                }
+
+                var text = OtherEncodings.BytesAsLatin1String(stream.ToArray());
+
+                text = text.Replace("\n", " ");
+                content = content.Replace("\r\n", " ");
+                content = replacementRegex.Replace(content, " 0$1");
+
+                Assert.Equal(content, text);
+            }
+        }
+
+        [Fact]
+        public void CorrectlyWritesSmallTextContent()
+        {
+            const string s = @"BT
+/F13 48 Tf
+20 38 Td
+1 Tr
+2 w
+(ABC) Tj
+ET";
+            var input = StringBytesTestConverter.Convert(s, false);
+
+            var result = parser.Parse(input.Bytes);
+
+            using (var stream = new MemoryStream())
+            {
+                foreach (var operation in result)
+                {
+                    operation.Write(stream);
+                }
+
+                var text = OtherEncodings.BytesAsLatin1String(stream.ToArray());
+
+                text = text.Replace("\n", " ").Trim();
+                var expected = s.Replace("\r\n", " ");
+
+                Assert.Equal(expected, text);
+            }
+        }
+
         [Fact]
         public void CorrectlyExtractsOptionsInTextContext()
         {

src/UglyToad.PdfPig.Tests/PublicApiScannerTests.cs

@@ -92,6 +92,7 @@
                 "UglyToad.PdfPig.Graphics.Operations.SpecialGraphicsState.ModifyCurrentTransformationMatrix",
                 "UglyToad.PdfPig.Graphics.Operations.SpecialGraphicsState.Pop",
                 "UglyToad.PdfPig.Graphics.Operations.SpecialGraphicsState.Push",
+                "UglyToad.PdfPig.Graphics.Operations.SpecialGraphicsState.SetGraphicsStateParametersFromDictionary",
                 "UglyToad.PdfPig.Graphics.Operations.StrokePath",
                 "UglyToad.PdfPig.Graphics.Operations.TextObjects.BeginText",
                 "UglyToad.PdfPig.Graphics.Operations.TextObjects.EndText",

src/UglyToad.PdfPig/Content/Page.cs

@@ -4,6 +4,7 @@
     using System.Collections.Generic;
     using System.Linq;
     using Annotations;
+    using Graphics.Operations;
     using Tokens;
     using Util;
     using Util.JetBrains.Annotations;
@@ -52,6 +53,11 @@
         /// </summary>
         public PageSize Size { get; }
 
+        /// <summary>
+        /// The parsed graphics state operations in the content stream for this page. 
+        /// </summary>
+        public IReadOnlyList<IGraphicsStateOperation> Operations => Content.GraphicsStateOperations;
+
         /// <summary>
         /// Access to members whose future locations within the API will change without warning.
         /// </summary>

src/UglyToad.PdfPig/Graphics/Operations/SpecialGraphicsState/SetGraphicsStateOperatorsFromDictionary.cs

@@ -0,0 +1,54 @@
+namespace UglyToad.PdfPig.Graphics.Operations.SpecialGraphicsState
+{
+    using System.IO;
+    using Tokens;
+
+    /// <inheritdoc />
+    /// <summary>
+    ///  Set the specified parameters in the graphics state using the ExtGState subdictionary with the given name.
+    /// </summary>
+    public class SetGraphicsStateParametersFromDictionary : IGraphicsStateOperation
+    {
+        /// <summary>
+        /// The symbol for this operation in a stream.
+        /// </summary>
+        public const string Symbol = "gs";
+
+        /// <inheritdoc />
+        public string Operator => Symbol;
+
+        /// <summary>
+        /// The name of a graphics state parameter dictionary in the ExtGState subdictionary of the current resource dictionary.
+        /// </summary>
+        public NameToken Name { get; }
+
+        /// <summary>
+        /// Create a new <see cref="SetGraphicsStateParametersFromDictionary"/>.
+        /// </summary>
+        /// <param name="name">The name of the ExtGState dictionary.</param>
+        public SetGraphicsStateParametersFromDictionary(NameToken name)
+        {
+            Name = name;
+        }
+
+        /// <inheritdoc />
+        public void Run(IOperationContext operationContext)
+        {
+        }
+
+        /// <inheritdoc />
+        public void Write(Stream stream)
+        {
+            stream.WriteText($"/{Name.Data}");
+            stream.WriteWhiteSpace();
+            stream.WriteText(Symbol);
+            stream.WriteNewLine();
+        }
+
+        /// <inheritdoc />
+        public override string ToString()
+        {
+            return $"{Name} {Symbol}";
+        }
+    }
+}