more tidy up of api for type 1 fonts

src/UglyToad.PdfPig/Fonts/Parser/Handlers/Type1FontHandler.cs

@@ -13,7 +13,6 @@
     using Tokenization.Tokens;
     using Type1;
     using Type1.Parser;
-    using Util;
 
     internal class Type1FontHandler : IFontHandler
     {

src/UglyToad.PdfPig/Fonts/Type1/CharStrings/Type1CharStrings.cs

@@ -8,6 +8,9 @@
 
     internal class Type1CharStrings
     {
+        private readonly object locker = new object();
+        private readonly Dictionary<string, CommandSequence> charStrings = new Dictionary<string, CommandSequence>();
+
         public IReadOnlyDictionary<string, CommandSequence> CharStrings { get; }
 
         public IReadOnlyDictionary<int, CommandSequence> Subroutines { get; }
@@ -18,8 +21,39 @@
             Subroutines = subroutines ?? throw new ArgumentNullException(nameof(subroutines));
         }
 
+        public void Generate(string name)
+        {
+            lock (locker)
+            {
+                if (charStrings.TryGetValue(name, out var result))
+                {
+                    return;
+                }
+            }
+
+            if (!CharStrings.TryGetValue(name, out var sequence))
+            {
+                throw new InvalidOperationException($"No charstring sequence with the name /{name} in this font.");
+            }
+
+            Run(sequence);
+
+            lock (locker)
+            {
+                charStrings[name] = sequence;
+            }
+        }
+
+        private void Run(CommandSequence sequence)
+        {
+
+        }
+
         public class CommandSequence
         {
+            /// <summary>
+            /// The ordered list of numbers and commands for a Type 1 charstring or subroutine.
+            /// </summary>
             public IReadOnlyList<DiscriminatedUnion<decimal, LazyType1Command>> Commands { get; }
 
             public CommandSequence(IReadOnlyList<DiscriminatedUnion<decimal, LazyType1Command>> commands)

src/UglyToad.PdfPig/Fonts/Type1/Parser/Type1EncryptedPortionParser.cs

@@ -7,7 +7,6 @@
     using IO;
     using PdfPig.Parser.Parts;
     using Tokenization.Tokens;
-    using Util;
 
     internal class Type1EncryptedPortionParser
     {
@@ -17,7 +16,7 @@
         private const int Password = 5839;
         private const int CharstringEncryptionKey = 4330;
 
-        public IReadOnlyList<byte> Parse(IReadOnlyList<byte> bytes, bool isLenientParsing)
+        public (Type1PrivateDictionary, Type1CharStrings) Parse(IReadOnlyList<byte> bytes, bool isLenientParsing)
         {
             if (!IsBinary(bytes))
             {
@@ -26,10 +25,8 @@
 
             var decrypted = Decrypt(bytes, EexecEncryptionKey, EexecRandomBytes);
             
-            // line 461 of type1parser.java
-            var str = OtherEncodings.BytesAsLatin1String(decrypted.ToArray());
-
             var tokenizer = new Type1Tokenizer(new ByteArrayInputBytes(decrypted));
+
             /*
              * After 4 random characters follows the /Private dictionary and the /CharString dictionary.
              * The first defines a number of technical terms involving character construction, and contains also an array of subroutines used in character paths.
@@ -54,8 +51,8 @@
 
             var length = next.AsInt();
             ReadExpected(tokenizer, Type1Token.TokenType.Name, "dict");
-            // actually could also be "/Private 10 dict def Private begin"
-            // instead of the "dup"
+            
+            // Could also be "/Private 10 dict def Private begin" instead of the "dup"
             ReadExpectedAfterOptional(tokenizer, Type1Token.TokenType.Name, "def", Type1Token.TokenType.Name, "dup");
             ReadExpected(tokenizer, Type1Token.TokenType.Name, "begin");
 
@@ -85,6 +82,7 @@
                     case Type1Symbols.RdProcedureAlt:
                         {
                             var procedureTokens = ReadProcedure(tokenizer);
+                            builder.Rd = procedureTokens;
                             ReadTillDef(tokenizer);
                             break;
                         }
@@ -92,6 +90,7 @@
                     case Type1Symbols.NoAccessDefAlt:
                         {
                             var procedureTokens = ReadProcedure(tokenizer);
+                            builder.NoAccessDef = procedureTokens;
                             ReadTillDef(tokenizer);
                             break;
                         }
@@ -99,6 +98,7 @@
                     case Type1Symbols.NoAccessPutAlt:
                         {
                             var procedureTokens = ReadProcedure(tokenizer);
+                            builder.NoAccessPut = procedureTokens;
                             ReadTillDef(tokenizer);
                             break;
                         }
@@ -290,14 +290,15 @@
                 charStrings = new Type1CharstringDecryptedBytes[0];
             }
 
+            var privateDictionary = builder.Build();
+
             var instructions = Type1CharStringParser.Parse(charStrings, builder.Subroutines ?? new Type1CharstringDecryptedBytes[0]);
 
-            return decrypted;
+            return (privateDictionary, instructions);
         }
 
         /// <summary>
-        /// To distinguish between binary and hex the first 4 bytes (of the ciphertext) for hex must
-        /// obey these restrictions:
+        /// To distinguish between binary and hex the first 4 bytes (of the ciphertext) for hex must obey these restrictions:
         /// The first byte must not be whitespace.
         /// One of the first four ciphertext bytes must not be an ASCII hex character.
         /// </summary>

src/UglyToad.PdfPig/Fonts/Type1/Parser/Type1FontParser.cs

@@ -146,9 +146,9 @@
             var matrix = GetFontMatrix(dictionaries);
             var boundingBox = GetBoundingBox(dictionaries);
 
-            var binaryPortion = encryptedPortionParser.Parse(eexecPortion, false);
+            var (privateDictionary, charStrings) = encryptedPortionParser.Parse(eexecPortion, false);
 
-            return new Type1Font(name, encoding, matrix, boundingBox ?? new PdfRectangle());
+            return new Type1Font(name, encoding, matrix, boundingBox ?? new PdfRectangle(), privateDictionary);
         }
 
         /// <summary>

src/UglyToad.PdfPig/Fonts/Type1/Type1Font.cs

@@ -1,7 +1,7 @@
 namespace UglyToad.PdfPig.Fonts.Type1
 {
+    using System;
     using System.Collections.Generic;
-    using Cos;
     using Geometry;
     using Tokenization.Tokens;
     using Util.JetBrains.Annotations;
@@ -21,12 +21,16 @@
         [CanBeNull]
         public PdfRectangle BoundingBox { get; }
 
-        public Type1Font(string name, IReadOnlyDictionary<int, string> encoding, ArrayToken fontMatrix, PdfRectangle boundingBox)
+        public Type1PrivateDictionary PrivateDictionary { get; }
+
+        public Type1Font(string name, IReadOnlyDictionary<int, string> encoding, ArrayToken fontMatrix, PdfRectangle boundingBox,
+            Type1PrivateDictionary privateDictionary)
         {
             Name = name;
             Encoding = encoding;
             FontMatrix = fontMatrix;
             BoundingBox = boundingBox;
+            PrivateDictionary = privateDictionary ?? throw new ArgumentNullException(nameof(privateDictionary));
         }
     }
 }

src/UglyToad.PdfPig/Fonts/Type1/Type1PrivateDictionary.cs

@@ -321,6 +321,15 @@
             /// <see cref="Type1PrivateDictionary.ExpansionFactor"/>.
             /// </summary>
             public decimal? ExpansionFactor { get; set; }
+
+            /// <summary>
+            /// Generate a <see cref="Type1PrivateDictionary"/> from the values in this builder.
+            /// </summary>
+            /// <returns>The generated <see cref="Type1PrivateDictionary"/>.</returns>
+            public Type1PrivateDictionary Build()
+            {
+                return new Type1PrivateDictionary(this);
+            }
         }
     }
 }