Large scale refactor to add class support!

Instance classes are now strongly typed with real property fields that
are derived from the JSON API Dump! This required a lot of reworking
across the board:

- Classes and Enums are auto-generated in the 'Generated' folder now.
This is done using a custom built-in plugin, which can be found in
the Plugins folder of this project.
- Property objects are now tied to .NET's reflection system. Reading
and writing from them will try to redirect into a field of the
Instance they are bound to.
- Property types that were loosely defined now have proper data types
(such as Color3uint8, Content, ProtectedString, SharedString, etc)
- Fixed an error with the CFrame directional vectors.
- The binary PRNT chunk now writes instances in child->parent order.
- Enums are now generated correctly, with up-to-date values.
- INST chunks are now referred to as 'Classes' instead of 'Types'.
- Unary operator added to Vector2 and Vector3.
- CollectionService tags can now be manipulated per-instance using
the Instance.Tags member.
- The Instance.Archivable property now works correctly.
- XML files now save/load metadata correctly.
- Cleaned up the property tokens directory.

I probably missed a few things, but that's a general overview of
everything that changed.

XmlFormat/IO/XmlFileReader.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Xml;
 
+using RobloxFiles.DataTypes;
+
 namespace RobloxFiles.XmlFormat
 {
     public static class XmlRobloxFileReader
@@ -35,11 +37,35 @@ namespace RobloxFiles.XmlFormat
                     string key = md5Node.InnerText;
                     string value = sharedString.InnerText.Replace("\n", "");
 
-                    file.SharedStrings.Add(key, value);
+                    byte[] buffer = Convert.FromBase64String(value);
+                    SharedString record = SharedString.FromBase64(value);
+
+                    if (record.MD5_Key != key)
+                        throw error("The provided md5 hash did not match with the md5 hash computed for the value!");
+
+                    file.SharedStrings.Add(key);
                 }
             }
         }
 
+        public static void ReadMetadata(XmlNode meta, XmlRobloxFile file)
+        {
+            var error = createErrorHandler("ReadMetadata");
+
+            if (meta.Name != "Meta")
+                throw error("Provided XmlNode's class should be 'Meta'!");
+
+            XmlNode propName = meta.Attributes.GetNamedItem("name");
+
+            if (propName == null)
+                throw error("Got a Meta node without a 'name' attribute!");
+
+            string key = propName.InnerText;
+            string value = meta.InnerText;
+
+            file.Metadata[key] = value;
+        }
+
         public static void ReadProperties(Instance instance, XmlNode propsNode)
         {
             var error = createErrorHandler("ReadProperties");
@@ -53,7 +79,12 @@ namespace RobloxFiles.XmlFormat
                 XmlNode propName = propNode.Attributes.GetNamedItem("name");
 
                 if (propName == null)
+                {
+                    if (propNode.Name == "Item")
+                        continue;
+
                     throw error("Got a property node without a 'name' attribute!");
+                }
 
                 IXmlPropertyToken tokenHandler = XmlPropertyTokens.GetHandler(propType);
 
@@ -90,8 +121,12 @@ namespace RobloxFiles.XmlFormat
             if (classToken == null)
                 throw error("Got an Item without a defined 'class' attribute!");
 
-            Instance inst = new Instance() { ClassName = classToken.InnerText };
 
+            string className = classToken.InnerText;
+
+            Type instType = Type.GetType($"RobloxFiles.{className}") ?? typeof(Instance);
+            Instance inst = Activator.CreateInstance(instType) as Instance;
+            
             // The 'referent' attribute is optional, but should be defined if a Ref property needs to link to this Instance.
             XmlNode refToken = instNode.Attributes.GetNamedItem("referent");
 

XmlFormat/IO/XmlFileWriter.cs

@@ -1,9 +1,8 @@
 using System;
-using System.Linq;
-using System.Security.Cryptography;
 using System.Text;
 using System.Xml;
 
+using RobloxFiles.DataTypes;
 using RobloxFiles.XmlFormat.PropertyTokens;
 
 namespace RobloxFiles.XmlFormat
@@ -40,7 +39,7 @@ namespace RobloxFiles.XmlFormat
             foreach (Instance child in inst.GetChildren())
                 RecordInstances(file, child);
 
-            if (inst.Referent.Length < 35)
+            if (inst.Referent == null || inst.Referent.Length < 35)
                 inst.Referent = CreateReferent();
 
             file.Instances.Add(inst.Referent, inst);
@@ -102,19 +101,8 @@ namespace RobloxFiles.XmlFormat
 
             if (prop.Type == PropertyType.SharedString)
             {
-                string data = prop.Value.ToString();
-                byte[] buffer = Convert.FromBase64String(data);
-
-                using (MD5 md5 = MD5.Create())
-                {
-                    byte[] hash = md5.ComputeHash(buffer);
-                    string key = Convert.ToBase64String(hash);
-
-                    if (!file.SharedStrings.ContainsKey(key))
-                        file.SharedStrings.Add(key, data);
-
-                    propNode.InnerText = key;
-                }
+                SharedString value = prop.CastValue<SharedString>();
+                file.SharedStrings.Add(value.MD5_Key);
             }
 
             return propNode;
@@ -122,6 +110,9 @@ namespace RobloxFiles.XmlFormat
 
         public static XmlNode WriteInstance(Instance instance, XmlDocument doc, XmlRobloxFile file)
         {
+            if (!instance.Archivable)
+                return null;
+
             XmlElement instNode = doc.CreateElement("Item");
             instNode.SetAttribute("class", instance.ClassName);
             instNode.SetAttribute("referent", instance.Referent);
@@ -129,7 +120,7 @@ namespace RobloxFiles.XmlFormat
             XmlElement propsNode = doc.CreateElement("Properties");
             instNode.AppendChild(propsNode);
 
-            var props = instance.Properties;
+            var props = instance.RefreshProperties();
             
             foreach (string propName in props.Keys)
             {
@@ -140,8 +131,11 @@ namespace RobloxFiles.XmlFormat
 
             foreach (Instance child in instance.GetChildren())
             {
-                XmlNode childNode = WriteInstance(child, doc, file);
-                instNode.AppendChild(childNode);
+                if (child.Archivable)
+                {
+                    XmlNode childNode = WriteInstance(child, doc, file);
+                    instNode.AppendChild(childNode);
+                }
             }
 
             return instNode;
@@ -152,18 +146,15 @@ namespace RobloxFiles.XmlFormat
             XmlElement sharedStrings = doc.CreateElement("SharedStrings");
 
             var binaryWriter = XmlPropertyTokens.GetHandler<BinaryStringToken>();
-            var bufferProp = new Property("SharedString", PropertyType.String);
+            var binaryBuffer = new Property("SharedString", PropertyType.String);
 
-            foreach (string md5 in file.SharedStrings.Keys)
+            foreach (string md5 in file.SharedStrings)
             {
                 XmlElement sharedString = doc.CreateElement("SharedString");
                 sharedString.SetAttribute("md5", md5);
 
-                string data = file.SharedStrings[md5];
-                byte[] buffer = Convert.FromBase64String(data);
-
-                bufferProp.RawBuffer = buffer;
-                binaryWriter.WriteProperty(bufferProp, doc, sharedString);
+                binaryBuffer.RawBuffer = SharedString.FindRecord(md5);
+                binaryWriter.WriteProperty(binaryBuffer, doc, sharedString);
 
                 sharedStrings.AppendChild(sharedString);
             }

XmlFormat/PropertyTokens/Tokens/Enum.cs

@@ -1,19 +0,0 @@
-using System.Xml;
-
-namespace RobloxFiles.XmlFormat.PropertyTokens
-{
-    public class EnumToken : IXmlPropertyToken
-    {
-        public string Token => "token";
-
-        public bool ReadProperty(Property prop, XmlNode token)
-        {
-            return XmlPropertyTokens.ReadPropertyGeneric<uint>(prop, PropertyType.Enum, token);
-        }
-
-        public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
-        {
-            node.InnerText = prop.Value.ToString();
-        }
-    }
-}

XmlFormat/Tokens/Axes.cs

@@ -1,5 +1,4 @@
-using System;
-using System.Xml;
+using System.Xml;
 using RobloxFiles.DataTypes;
 
 namespace RobloxFiles.XmlFormat.PropertyTokens
@@ -7,25 +6,20 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
     public class AxesToken : IXmlPropertyToken
     {
         public string Token => "Axes";
+
         public bool ReadProperty(Property prop, XmlNode token)
         {
-            bool success = XmlPropertyTokens.ReadPropertyGeneric<uint>(prop, PropertyType.Axes, token);
+            uint value;
 
-            if (success)
+            if (XmlPropertyTokens.ReadPropertyGeneric(token, out value))
             {
-                uint value = (uint)prop.Value;
-                try
-                {
-                    Axes axes = (Axes)value;
-                    prop.Value = axes;
-                }
-                catch
-                {
-                    success = false;
-                }
+                Axes axes = (Axes)value;
+                prop.Value = axes;
+
+                return true;
             }
 
-            return success;
+            return false;
         }
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
@@ -33,7 +27,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
             XmlElement axes = doc.CreateElement("axes");
             node.AppendChild(axes);
 
-            int value = (int)prop.Value;
+            int value = prop.CastValue<int>();
             axes.InnerText = value.ToInvariantString();
         }
     }

XmlFormat/Tokens/BinaryString.cs

@@ -11,9 +11,9 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
         {
             // BinaryStrings are encoded in base64
             string base64 = token.InnerText.Replace("\n", "");
+            prop.Value = Convert.FromBase64String(base64);
             prop.Type = PropertyType.String;
-            prop.Value = base64;
-
+            
             byte[] buffer = Convert.FromBase64String(base64);
             prop.RawBuffer = buffer;
             

XmlFormat/Tokens/BrickColor.cs

@@ -13,31 +13,23 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public bool ReadProperty(Property prop, XmlNode token)
         {
-            bool success = XmlPropertyTokens.ReadPropertyGeneric<int>(prop, PropertyType.BrickColor, token);
+            int value;
 
-            if (success)
+            if (XmlPropertyTokens.ReadPropertyGeneric(token, out value))
             {
-                int value = (int)prop.Value;
+                BrickColor brickColor = BrickColor.FromNumber(value);
+                prop.XmlToken = "BrickColor";
+                prop.Value = brickColor;
 
-                try
-                {
-                    BrickColor brickColor = BrickColor.FromNumber(value);
-                    prop.XmlToken = "BrickColor";
-                    prop.Value = brickColor;
-                }
-                catch
-                {
-                    // Invalid BrickColor Id?
-                    success = false;
-                }
+                return true;
             }
             
-            return success;
+            return false;
         }
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            BrickColor value = prop.Value as BrickColor;
+            BrickColor value = prop.CastValue<BrickColor>();
 
             XmlElement brickColor = doc.CreateElement("int");
             brickColor.InnerText = value.Number.ToInvariantString();

XmlFormat/Tokens/CFrame.cs

@@ -46,7 +46,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            CFrame cf = prop.Value as CFrame;
+            CFrame cf = prop.CastValue<CFrame>();
             float[] components = cf.GetComponents();
 
             for (int i = 0; i < 12; i++)

XmlFormat/Tokens/Color3.cs

@@ -51,26 +51,18 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            if (prop.Name == "Color3uint8")
+            Color3 color = prop.CastValue<Color3>();
+            float[] rgb = new float[3] { color.R, color.G, color.B };
+
+            for (int i = 0; i < 3; i++)
             {
-                var handler = XmlPropertyTokens.GetHandler<Color3uint8Token>();
-                handler.WriteProperty(prop, doc, node);
-            }
-            else
-            {
-                Color3 color = prop.Value as Color3;
-                float[] rgb = new float[3] { color.R, color.G, color.B };
+                string field = Fields[i];
+                float value = rgb[i];
 
-                for (int i = 0; i < 3; i++)
-                {
-                    string field = Fields[i];
-                    float value = rgb[i];
+                XmlElement channel = doc.CreateElement(field);
+                channel.InnerText = value.ToInvariantString();
 
-                    XmlElement channel = doc.CreateElement(field);
-                    channel.InnerText = value.ToInvariantString();
-
-                    node.AppendChild(channel);
-                }
+                node.AppendChild(channel);
             }
         }
     }

XmlFormat/Tokens/Color3uint8.cs

@@ -1,5 +1,4 @@
-using System;
-using System.Xml;
+using System.Xml;
 using RobloxFiles.DataTypes;
 
 namespace RobloxFiles.XmlFormat.PropertyTokens
@@ -10,29 +9,30 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public bool ReadProperty(Property prop, XmlNode token)
         {
-            bool success = XmlPropertyTokens.ReadPropertyGeneric<uint>(prop, PropertyType.Color3, token);
+            uint value;
 
-            if (success)
+            if (XmlPropertyTokens.ReadPropertyGeneric(token, out value))
             {
-                uint value = (uint)prop.Value;
-
                 uint r = (value >> 16) & 0xFF;
                 uint g = (value >> 8) & 0xFF;
                 uint b = value & 0xFF;
 
-                prop.Value = Color3.FromRGB(r, g, b);
+                Color3uint8 result = Color3.FromRGB(r, g, b);
+                prop.Value = result;
+
+                return true;
             }
             
-            return success;
+            return false;
         }
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            Color3 color = prop.Value as Color3;
+            Color3uint8 color = prop.CastValue<Color3uint8>();
 
-            uint r = (uint)(color.R * 256);
-            uint g = (uint)(color.G * 256);
-            uint b = (uint)(color.B * 256);
+            uint r = color.R,
+                 g = color.G,
+                 b = color.B;
 
             uint rgb = (255u << 24) | (r << 16) | (g << 8) | b;
             node.InnerText = rgb.ToString();

XmlFormat/Tokens/ColorSequence.cs

@@ -47,7 +47,8 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            node.InnerText = prop.Value.ToString() + ' ';
+            ColorSequence value = prop.CastValue<ColorSequence>();
+            node.InnerText = value.ToString() + ' ';
         }
     }
 }

XmlFormat/Tokens/Content.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Xml;
 
+using RobloxFiles.DataTypes;
+
 namespace RobloxFiles.XmlFormat.PropertyTokens
 {
     public class ContentToken : IXmlPropertyToken
@@ -9,9 +11,9 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public bool ReadProperty(Property prop, XmlNode token)
         {
-            string content = token.InnerText;
+            string data = token.InnerText;
+            prop.Value = new Content(data);
             prop.Type = PropertyType.String;
-            prop.Value = content;
 
             if (token.HasChildNodes)
             {
@@ -23,12 +25,12 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
                     try
                     {
                         // Roblox technically doesn't support this anymore, but load it anyway :P
-                        byte[] buffer = Convert.FromBase64String(content);
+                        byte[] buffer = Convert.FromBase64String(data);
                         prop.RawBuffer = buffer;
                     }
                     catch
                     {
-                        Console.WriteLine("ContentToken: Got illegal base64 string: {0}", content);
+                        Console.WriteLine("ContentToken: Got illegal base64 string: {0}", data);
                     }
                 }
             }
@@ -38,7 +40,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            string content = prop.Value.ToString();
+            string content = prop.CastValue<Content>();
             string type = "null";
 
             if (prop.HasRawBuffer)

XmlFormat/Tokens/Double.cs

@@ -13,7 +13,8 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            node.InnerText = prop.Value.ToInvariantString();
+            double value = prop.CastValue<double>();
+            node.InnerText = value.ToInvariantString();
         }
     }
 }

XmlFormat/Tokens/Enum.cs

@@ -0,0 +1,48 @@
+using System;
+using System.Reflection;
+using System.Xml;
+
+namespace RobloxFiles.XmlFormat.PropertyTokens
+{
+    public class EnumToken : IXmlPropertyToken
+    {
+        public string Token => "token";
+
+        public bool ReadProperty(Property prop, XmlNode token)
+        {
+            uint value;
+
+            if (XmlPropertyTokens.ReadPropertyGeneric(token, out value))
+            {
+                Instance inst = prop.Instance;
+                Type instType = inst?.GetType();
+
+                FieldInfo info = instType.GetField(prop.Name, Property.BindingFlags);
+
+                if (info != null)
+                {
+                    Type enumType = info.FieldType;
+                    string item = value.ToInvariantString();
+
+                    prop.Type = PropertyType.Enum;
+                    prop.Value = Enum.Parse(enumType, item);
+
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
+        public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
+        {
+            object rawValue = prop.Value;
+            Type valueType = rawValue.GetType();
+
+            int signed = (int)rawValue;
+            uint value = (uint)signed;
+
+            node.InnerText = value.ToString();
+        }
+    }
+}

XmlFormat/Tokens/Faces.cs

@@ -9,23 +9,17 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public bool ReadProperty(Property prop, XmlNode token)
         {
-            bool success = XmlPropertyTokens.ReadPropertyGeneric<uint>(prop, PropertyType.Faces, token);
+            uint value;
 
-            if (success)
+            if (XmlPropertyTokens.ReadPropertyGeneric(token, out value))
             {
-                uint value = (uint)prop.Value;
-                try
-                {
-                    Faces faces = (Faces)value;
-                    prop.Value = faces;
-                }
-                catch
-                {
-                    success = false;
-                }
+                Faces faces = (Faces)value;
+                prop.Value = faces;
+
+                return true;
             }
 
-            return success;
+            return false;
         }
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
@@ -33,7 +27,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
             XmlElement faces = doc.CreateElement("faces");
             node.AppendChild(faces);
 
-            int value = (int)prop.Value;
+            int value = prop.CastValue<int>();
             faces.InnerText = value.ToInvariantString();
         }
     }

XmlFormat/Tokens/Float.cs

@@ -13,7 +13,8 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            node.InnerText = prop.Value.ToInvariantString();
+            float value = prop.CastValue<float>();
+            node.InnerText = value.ToInvariantString();
         }
     }
 }

XmlFormat/Tokens/Int.cs

@@ -24,7 +24,8 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            node.InnerText = prop.Value.ToInvariantString();
+            int value = prop.CastValue<int>();
+            node.InnerText = value.ToInvariantString();
         }
     }
 }

XmlFormat/Tokens/Int64.cs

@@ -13,7 +13,8 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            node.InnerText = prop.Value.ToString();
+            long value = prop.CastValue<long>();
+            node.InnerText = value.ToString();
         }
     }
 }

XmlFormat/Tokens/NumberRange.cs

@@ -35,7 +35,8 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            node.InnerText = prop.Value.ToString() + ' ';
+            NumberRange value = prop.CastValue<NumberRange>();
+            node.InnerText = value.ToString() + ' ';
         }
     }
 }

XmlFormat/Tokens/NumberSequence.cs

@@ -44,7 +44,8 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            node.InnerText = prop.Value.ToString() + ' ';
+            NumberSequence value = prop.CastValue<NumberSequence>();
+            node.InnerText = value.ToString() + ' ';
         }
     }
 }

XmlFormat/Tokens/PhysicalProperties.cs

@@ -61,7 +61,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
             if (hasCustomPhysics)
             {
-                var customProps = prop.Value as PhysicalProperties;
+                var customProps = prop.CastValue<PhysicalProperties>();
                 
                 var data = new Dictionary<string, float>()
                 {

XmlFormat/Tokens/ProtectedString.cs

@@ -0,0 +1,34 @@
+using System.Xml;
+using RobloxFiles.DataTypes;
+
+namespace RobloxFiles.XmlFormat.PropertyTokens
+{
+    public class ProtectedStringToken : IXmlPropertyToken
+    {
+        public string Token => "ProtectedString";
+
+        public bool ReadProperty(Property prop, XmlNode token)
+        {
+            ProtectedString contents = token.InnerText;
+            prop.Type = PropertyType.String;
+            prop.Value = contents;
+
+            return true;
+        }
+
+        public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
+        {
+            string value = prop.CastValue<ProtectedString>();
+
+            if (value.Contains("\r") || value.Contains("\n"))
+            {
+                XmlCDataSection cdata = doc.CreateCDataSection(value);
+                node.AppendChild(cdata);
+            }
+            else
+            {
+                node.InnerText = value;
+            }
+        }
+    }
+}

XmlFormat/Tokens/Ray.cs

@@ -39,7 +39,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            Ray ray = prop.Value as Ray;
+            Ray ray = prop.CastValue<Ray>();
 
             XmlElement origin = doc.CreateElement("origin");
             XmlElement direction = doc.CreateElement("direction");

XmlFormat/Tokens/Rect.cs

@@ -39,7 +39,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            Rect rect = prop.Value as Rect;
+            Rect rect = prop.CastValue<Rect>();
 
             XmlElement min = doc.CreateElement("min");
             Vector2Token.WriteVector2(doc, min, rect.Min);

XmlFormat/Tokens/Ref.cs

@@ -10,7 +10,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
         {
             string refId = token.InnerText;
             prop.Type = PropertyType.Ref;
-            prop.Value = refId;
+            prop.XmlToken = refId;
 
             return true;
         }
@@ -19,9 +19,9 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
         {
             string result = "null";
 
-            if (prop.Value != null && prop.Value.ToString() != "null")
+            if (prop.Value != null)
             {
-                Instance inst = prop.Value as Instance;
+                Instance inst = prop.CastValue<Instance>();
                 result = inst.Referent;
             }
 

XmlFormat/Tokens/SharedString.cs

@@ -1,6 +1,5 @@
-using System;
-using System.Text;
-using System.Xml;
+using System.Xml;
+using RobloxFiles.DataTypes;
 
 namespace RobloxFiles.XmlFormat.PropertyTokens
 {
@@ -10,17 +9,17 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public bool ReadProperty(Property prop, XmlNode token)
         {
-            string contents = token.InnerText;
+            string md5 = token.InnerText;
             prop.Type = PropertyType.SharedString;
-            prop.Value = contents;
+            prop.Value = new SharedString(md5);
 
             return true;
         }
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            var BinaryStringToken = XmlPropertyTokens.GetHandler<BinaryStringToken>();
-            BinaryStringToken.WriteProperty(prop, doc, node);
+            SharedString value = prop.CastValue<SharedString>();
+            node.InnerText = value.MD5_Key;
         }
     }
 }

XmlFormat/Tokens/String.cs

@@ -1,12 +1,10 @@
-using System;
-using System.Text;
-using System.Xml;
+using System.Xml;
 
 namespace RobloxFiles.XmlFormat.PropertyTokens
 {
     public class StringToken : IXmlPropertyToken
     {
-        public string Token => "string; ProtectedString";
+        public string Token => "string";
 
         public bool ReadProperty(Property prop, XmlNode token)
         {

XmlFormat/Tokens/UDim.cs

@@ -53,7 +53,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            UDim value = prop.Value as UDim;
+            UDim value = prop.CastValue<UDim>();
             WriteUDim(doc, node, value);
         }
     }

XmlFormat/Tokens/UDim2.cs

@@ -26,7 +26,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            UDim2 value = prop.Value as UDim2;
+            UDim2 value = prop.CastValue<UDim2>();
 
             UDim xUDim = value.X;
             UDimToken.WriteUDim(doc, node, xUDim, "X");

XmlFormat/Tokens/Vector2.cs

@@ -58,7 +58,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            Vector2 value = prop.Value as Vector2;
+            Vector2 value = prop.CastValue<Vector2>();
             WriteVector2(doc, node, value);
         }
     }

XmlFormat/Tokens/Vector3.cs

@@ -62,7 +62,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            Vector3 value = prop.Value as Vector3;
+            Vector3 value = prop.CastValue<Vector3>();
             WriteVector3(doc, node, value);
         }
     }

XmlFormat/Tokens/Vector3int16.cs

@@ -39,7 +39,7 @@ namespace RobloxFiles.XmlFormat.PropertyTokens
 
         public void WriteProperty(Property prop, XmlDocument doc, XmlNode node)
         {
-            Vector3int16 value = prop.Value as Vector3int16;
+            Vector3int16 value = prop.CastValue<Vector3int16>();
 
             XmlElement x = doc.CreateElement("X");
             x.InnerText = value.X.ToString();

XmlFormat/XmlPropertyTokens.cs

@@ -35,38 +35,54 @@ namespace RobloxFiles.XmlFormat
             Handlers = tokenHandlers;
         }
 
-        public static bool ReadPropertyGeneric<T>(Property prop, PropertyType propType, XmlNode token) where T : struct
+        public static bool ReadPropertyGeneric<T>(XmlNode token, out T outValue) where T : struct
         {
             try
             {
                 string value = token.InnerText;
                 Type type = typeof(T);
 
-                if (type == typeof(int))
-                    prop.Value = Formatting.ParseInt(value);
-                else if (type == typeof(float))
-                    prop.Value = Formatting.ParseFloat(value);
-                else if (type == typeof(double))
-                    prop.Value = Formatting.ParseDouble(value);
+                object result = null;
 
-                if (prop.Value == null)
+                if (type == typeof(int))
+                    result = Formatting.ParseInt(value);
+                else if (type == typeof(float))
+                    result = Formatting.ParseFloat(value);
+                else if (type == typeof(double))
+                    result = Formatting.ParseDouble(value);
+
+                if (result == null)
                 {
                     Type resultType = typeof(T);
-                    TypeConverter converter = TypeDescriptor.GetConverter(resultType);
-
-                    object result = converter.ConvertFromString(token.InnerText);
-                    prop.Value = result;
+                    var converter = TypeDescriptor.GetConverter(resultType);
+                    result = converter.ConvertFromString(token.InnerText);
                 }
 
-                prop.Type = propType;
+                outValue = (T)result;
                 return true;
             }
             catch
             {
+                outValue = default(T);
                 return false;
             }
         }
 
+        public static bool ReadPropertyGeneric<T>(Property prop, PropertyType propType, XmlNode token) where T : struct
+        {
+            T result;
+
+            if (ReadPropertyGeneric(token, out result))
+            {
+                prop.Type = propType;
+                prop.Value = result;
+
+                return true;
+            }
+
+            return false;
+        }
+
         public static IXmlPropertyToken GetHandler(string tokenName)
         {
             IXmlPropertyToken result = null;

XmlFormat/XmlRobloxFile.cs

@@ -6,20 +6,26 @@ using System.Linq;
 using System.Text;
 using System.Xml;
 
-namespace RobloxFiles.XmlFormat
+using RobloxFiles.DataTypes;
+using RobloxFiles.XmlFormat;
+
+namespace RobloxFiles
 {
     public class XmlRobloxFile : RobloxFile
     {
-        // Runtime Specific
-        public readonly XmlDocument Root = new XmlDocument();
+        public readonly XmlDocument XmlDocument = new XmlDocument();
 
         internal Dictionary<string, Instance> Instances = new Dictionary<string, Instance>();
-        internal Dictionary<string, string> SharedStrings = new Dictionary<string, string>();
+        internal HashSet<string> SharedStrings = new HashSet<string>();
 
-        internal XmlRobloxFile()
+        private Dictionary<string, string> RawMetadata = new Dictionary<string, string>();
+        public Dictionary<string, string> Metadata => RawMetadata;
+
+        public XmlRobloxFile()
         {
             Name = "XmlRobloxFile";
             ParentLocked = true;
+            Referent = "null";
         }
         
         protected override void ReadFile(byte[] buffer)
@@ -27,14 +33,14 @@ namespace RobloxFiles.XmlFormat
             try
             {
                 string xml = Encoding.UTF8.GetString(buffer);
-                Root.LoadXml(xml);
+                XmlDocument.LoadXml(xml);
             }
             catch
             {
                 throw new Exception("XmlRobloxFile: Could not read provided buffer as XML!");
             }
 
-            XmlNode roblox = Root.FirstChild;
+            XmlNode roblox = XmlDocument.FirstChild;
             
             if (roblox != null && roblox.Name == "roblox")
             {
@@ -59,6 +65,10 @@ namespace RobloxFiles.XmlFormat
                     {
                         XmlRobloxFileReader.ReadSharedStrings(child, this);
                     }
+                    else if (child.Name == "Meta")
+                    {
+                        XmlRobloxFileReader.ReadMetadata(child, this);
+                    }
                 }
 
                 // Query the properties.
@@ -71,7 +81,8 @@ namespace RobloxFiles.XmlFormat
                   
                 foreach (Property refProp in refProps)
                 {
-                    string refId = refProp.Value as string;
+                    string refId = refProp.XmlToken;
+                    refProp.XmlToken = "Ref";
 
                     if (Instances.ContainsKey(refId))
                     {
@@ -86,26 +97,13 @@ namespace RobloxFiles.XmlFormat
                     }
                 }
 
-                // Resolve shared strings.
+                // Record shared strings.
                 var sharedProps = allProps.Where(prop => prop.Type == PropertyType.SharedString);
 
                 foreach (Property sharedProp in sharedProps)
                 {
-                    string md5 = sharedProp.Value as string;
-
-                    if (SharedStrings.ContainsKey(md5))
-                    {
-                        string value = SharedStrings[md5];
-                        sharedProp.Value = value;
-
-                        byte[] data = Convert.FromBase64String(value);
-                        sharedProp.RawBuffer = data;
-                    }
-                    else
-                    {
-                        string name = sharedProp.GetFullName();
-                        Console.WriteLine("XmlRobloxFile: Could not resolve shared string for {0}", name);
-                    }
+                    SharedString shared = sharedProp.CastValue<SharedString>();
+                    SharedStrings.Add(shared.MD5_Key);
                 }
             }
             else
@@ -125,17 +123,32 @@ namespace RobloxFiles.XmlFormat
             Instances.Clear();
             SharedStrings.Clear();
 
+            // First, append the metadata
+            foreach (string key in Metadata.Keys)
+            {
+                string value = Metadata[key];
+
+                XmlElement meta = doc.CreateElement("Meta");
+                meta.SetAttribute("name", key);
+                meta.InnerText = value;
+                
+                roblox.AppendChild(meta);
+            }
+
             Instance[] children = GetChildren();
 
-            // First, record all of the instances.
+            // Record all of the instances.
             foreach (Instance inst in children)
                 XmlRobloxFileWriter.RecordInstances(this, inst);
 
             // Now append them into the document.
             foreach (Instance inst in children)
             {
-                XmlNode instNode = XmlRobloxFileWriter.WriteInstance(inst, doc, this);
-                roblox.AppendChild(instNode);
+                if (inst.Archivable)
+                {
+                    XmlNode instNode = XmlRobloxFileWriter.WriteInstance(inst, doc, this);
+                    roblox.AppendChild(instNode);
+                }
             }
 
             // Append the shared strings.