changes for intital InusualZ review

src/UglyToad.PdfPig/Writer/PdfDedupStreamWriter.cs

@@ -1,33 +1,19 @@
 namespace UglyToad.PdfPig.Writer
 {
-using Core;
-    using Graphics.Operations;
-    using System;
     using System.Collections.Generic;
-    using System.Globalization;
     using System.IO;
-    using System.Text;
     using Tokens;
 
-    internal class PdfDedupStreamWriter : IPdfStreamWriter
+    internal class PdfDedupStreamWriter : PdfStreamWriter
     {
-
-        public Stream Stream { get; }
-        private int CurrentNumber { get; set; } = 1;
-        private bool DisposeStream { get; set; }
-        private const decimal DefaultVersion = 1.2m;
-        private bool Initialized { get; set; }
-        private readonly Dictionary<IndirectReference, long> offsets = new Dictionary<IndirectReference, long>();
         private readonly Dictionary<byte[], IndirectReferenceToken> hashes = new Dictionary<byte[], IndirectReferenceToken>(new FNVByteComparison());
 
-        public PdfDedupStreamWriter(Stream stream, bool dispose)
+        public PdfDedupStreamWriter(Stream stream, bool dispose) : base(stream, dispose)
         {
-            Stream = stream;
-            DisposeStream = dispose;
         }
 
-        private MemoryStream ms = new MemoryStream();
+        private readonly MemoryStream ms = new MemoryStream();
-        public IndirectReferenceToken WriteToken(IToken token)
+        public override IndirectReferenceToken WriteToken(IToken token)
         {
             if (!Initialized)
             {
@@ -51,7 +37,7 @@ using Core;
             return ir;
         }
 
-        public IndirectReferenceToken WriteToken(IToken token, IndirectReferenceToken indirectReference)
+        public override IndirectReferenceToken WriteToken(IToken token, IndirectReferenceToken indirectReference)
         {
             if (!Initialized)
             {
@@ -68,45 +54,10 @@ using Core;
             return indirectReference;
         }
 
-        public IndirectReferenceToken ReserveObjectNumber()
+        public new void Dispose()
         {
-            return new IndirectReferenceToken(new IndirectReference(CurrentNumber++, 0));
-        }
-
-        public void InitializePdf(decimal version)
-        {
-            WriteString($"%PDF-{version.ToString("0.0", CultureInfo.InvariantCulture)}", Stream);
-
-            Stream.WriteText("%");
-            Stream.WriteByte(169);
-            Stream.WriteByte(205);
-            Stream.WriteByte(196);
-            Stream.WriteByte(210);
-            Stream.WriteNewLine();
-
-            Initialized = true;
-        }
-
-        public void CompletePdf(IndirectReferenceToken catalogReference, IndirectReferenceToken documentInformationReference=null)
-        {
-            TokenWriter.WriteCrossReferenceTable(offsets, catalogReference.Data, Stream, documentInformationReference?.Data);
-        }
-
-        private static void WriteString(string text, Stream stream)
-        {
-            var bytes = OtherEncodings.StringAsLatin1Bytes(text);
-            stream.Write(bytes, 0, bytes.Length);
-            stream.WriteNewLine();
-        }
-
-        public void Dispose()
-        {
-            if (DisposeStream)
-            {
-                Stream.Dispose();
-            }
-
             hashes.Clear();
+            base.Dispose();
         }
 
         class FNVByteComparison : IEqualityComparer<byte[]>

src/UglyToad.PdfPig/Writer/PdfDocumentBuilder.cs

@@ -284,7 +284,7 @@ namespace UglyToad.PdfPig.Writer
         internal class PageInfo
         {
             public DictionaryToken Page { get; set; }
-            public List<DictionaryToken> Parents { get; set; }
+            public IReadOnlyList<DictionaryToken> Parents { get; set; }
         }
         private readonly ConditionalWeakTable<IPdfTokenScanner, Dictionary<IndirectReference, IndirectReferenceToken>> existingCopies = 
             new ConditionalWeakTable<IPdfTokenScanner, Dictionary<IndirectReference, IndirectReferenceToken>>();
@@ -320,18 +320,15 @@ namespace UglyToad.PdfPig.Writer
                 existingTrees.Add(document, pagesInfos);
             }
 
-            if (!pagesInfos.ContainsKey(pageNumber))
+            if (!pagesInfos.TryGetValue(pageNumber, out PageInfo pageInfo))
             {
                 throw new KeyNotFoundException($"Page {pageNumber} was not found in the source document.");
             }
 
-            var pageInfo = pagesInfos[pageNumber];
-
             // copy content streams
             var streams = new List<PdfPageBuilder.CopiedContentStream>();
-            if (pageInfo.Page.ContainsKey(NameToken.Contents))
+            if (pageInfo.Page.TryGet(NameToken.Contents, out IToken token))
             {
-                var token = pageInfo.Page.Data[NameToken.Contents];
                 if (token is ArrayToken array)
                 {
                     foreach (var item in array.Data)
@@ -358,9 +355,9 @@ namespace UglyToad.PdfPig.Writer
             // just put all parent resources into new page
             foreach (var dict in pageInfo.Parents)
             {
-                if (dict.TryGet(NameToken.Resources, out var token))
+                if (dict.TryGet(NameToken.Resources, out var resourceToken))
                 {
-                    CopyResourceDict(token, resources);
+                    CopyResourceDict(resourceToken, resources);
                 }
             }
 
@@ -382,6 +379,8 @@ namespace UglyToad.PdfPig.Writer
                     WriterUtil.CopyToken(context, kvp.Value, document.Structure.TokenScanner, refs);
             }
 
+            // LocalizeFontAndXObject(resources); TODO work in progress
+
             copiedPageDict[NameToken.Resources] = new DictionaryToken(resources);
 
             var builder = new PdfPageBuilder(pages.Count + 1, this, streams, copiedPageDict);
@@ -453,7 +452,7 @@ namespace UglyToad.PdfPig.Writer
                 font.Value.FontProgram.WriteFont(context, font.Value.FontKey.Reference);
             }
 
-            int desiredLeafSize = 25;
+            const int desiredLeafSize = 25; // allow customization at some point?
             var numLeafs = (int) Math.Ceiling(Decimal.Divide(Pages.Count, desiredLeafSize));
 
             var leafRefs = new List<IndirectReferenceToken>();

src/UglyToad.PdfPig/Writer/PdfPageBuilder.cs

@@ -747,15 +747,6 @@
             return value;
         }
 
-        internal interface IPageContentStream : IContentStream
-        {
-            bool ReadOnly { get; }
-            bool HasContent { get; }
-            void Add(IGraphicsStateOperation operation);
-            IndirectReferenceToken Write(IPdfStreamWriter writer);
-
-        }
-
         /// <summary>
         /// Provides access to the raw page data structures for advanced editing use cases.
         /// </summary>
@@ -767,6 +758,15 @@
             List<IGraphicsStateOperation> Operations { get; }
         }
 
+        internal interface IPageContentStream : IContentStream
+        {
+            bool ReadOnly { get; }
+            bool HasContent { get; }
+            void Add(IGraphicsStateOperation operation);
+            IndirectReferenceToken Write(IPdfStreamWriter writer);
+
+        }
+
         internal class DefaultContentStream : IPageContentStream
         {
             private readonly List<IGraphicsStateOperation> operations;

src/UglyToad.PdfPig/Writer/PdfStreamWriter.cs

@@ -13,16 +13,13 @@
     /// </summary>
     internal class PdfStreamWriter : IPdfStreamWriter
     {
-        private Dictionary<IndirectReference, long> offsets = new Dictionary<IndirectReference, long>();
+        protected const decimal DefaultVersion = 1.2m;
-        private const decimal DefaultVersion = 1.2m;
+        protected Dictionary<IndirectReference, long> offsets = new Dictionary<IndirectReference, long>();
-        private bool Initialized { get; set; }
+        protected bool DisposeStream { get; set; }
-        private int CurrentNumber { get; set; } = 1;
+        protected bool Initialized { get; set; }
+        protected int CurrentNumber { get; set; } = 1;
 
-        public Stream Stream { get; set; }
+        internal PdfStreamWriter(Stream baseStream, bool disposeStream = true)
-
-        private bool DisposeStream { get; set; }
-
-        public PdfStreamWriter(Stream baseStream, bool disposeStream = true)
         {
             Stream = baseStream ?? throw new ArgumentNullException(nameof(baseStream));
             if (!baseStream.CanWrite)
@@ -33,40 +30,9 @@
             DisposeStream = disposeStream;
         }
 
-        public void InitializePdf(decimal version)
+        public Stream Stream { get; protected set; }
-        {
-            WriteString($"%PDF-{version.ToString("0.0", CultureInfo.InvariantCulture)}", Stream);
 
-            Stream.WriteText("%");
+        public virtual IndirectReferenceToken WriteToken(IToken token)
-            Stream.WriteByte(169);
-            Stream.WriteByte(205);
-            Stream.WriteByte(196);
-            Stream.WriteByte(210);
-            Stream.WriteNewLine();
-            Initialized = true;
-        }
-
-        public void Dispose()
-        {
-            if (!DisposeStream)
-            {
-                Stream = null;
-                return;
-            }
-
-            Stream?.Dispose();
-            Stream = null;
-        }
-
-
-        private static void WriteString(string text, Stream stream)
-        {
-            var bytes = OtherEncodings.StringAsLatin1Bytes(text);
-            stream.Write(bytes, 0, bytes.Length);
-            stream.WriteNewLine();
-        }
-
-        public IndirectReferenceToken WriteToken(IToken token)
         {
             if (!Initialized)
             {
@@ -80,7 +46,7 @@
             return ir;
         }
 
-        public IndirectReferenceToken WriteToken(IToken token, IndirectReferenceToken indirectReference)
+        public virtual IndirectReferenceToken WriteToken(IToken token, IndirectReferenceToken indirectReference)
         {
             if (!Initialized)
             {
@@ -98,10 +64,39 @@
             return new IndirectReferenceToken(new IndirectReference(CurrentNumber++, 0));
         }
 
+        public void InitializePdf(decimal version)
+        {
+            WriteString($"%PDF-{version.ToString("0.0", CultureInfo.InvariantCulture)}", Stream);
+
+            Stream.WriteText("%");
+            Stream.WriteByte(169);
+            Stream.WriteByte(205);
+            Stream.WriteByte(196);
+            Stream.WriteByte(210);
+            Stream.WriteNewLine();
+            Initialized = true;
+        }
 
         public void CompletePdf(IndirectReferenceToken catalogReference, IndirectReferenceToken documentInformationReference = null)
         {
             TokenWriter.WriteCrossReferenceTable(offsets, catalogReference.Data, Stream, documentInformationReference?.Data);
         }
+
+        private static void WriteString(string text, Stream stream)
+        {
+            var bytes = OtherEncodings.StringAsLatin1Bytes(text);
+            stream.Write(bytes, 0, bytes.Length);
+            stream.WriteNewLine();
+        }
+
+        public void Dispose()
+        {
+            if (DisposeStream)
+            {
+                Stream?.Dispose();
+            }
+            
+            Stream = null;
+        }
     }
 }

src/UglyToad.PdfPig/Writer/WriterUtil.cs

@@ -14,9 +14,8 @@
     {
         public static Dictionary<string, IToken> GetOrCreateDict(this Dictionary<NameToken, IToken> dict,  NameToken key)
         {
-            if (dict.ContainsKey(key))
+            if (dict.TryGetValue(key, out var item))
             {
-                var item = dict[key];
                 if (!(item is DictionaryToken dt))
                 {
                     throw new ApplicationException("Expected dictionary token, got " + item.GetType());
@@ -40,9 +39,8 @@
 
         public static Dictionary<string, IToken> GetOrCreateDict(this Dictionary<string, IToken> dict,  string key)
         {
-            if (dict.ContainsKey(key))
+            if (dict.TryGetValue(key, out var item))
             {
-                var item = dict[key];
                 if (!(item is DictionaryToken dt))
                 {
                     throw new ApplicationException("Expected dictionary token, got " + item.GetType());
@@ -161,7 +159,7 @@
             return tokenToCopy;
         }
 
-        internal static IEnumerable<(DictionaryToken, List<DictionaryToken>)> WalkTree(PageTreeNode node, List<DictionaryToken> parents=null)
+        internal static IEnumerable<(DictionaryToken, IReadOnlyList<DictionaryToken>)> WalkTree(PageTreeNode node, List<DictionaryToken> parents=null)
         {
             if (parents == null)
             {