feat: Source generated Serialization/Deserialization (#550)

### Features
* Fully abstracts serialization by using compile-time attributes.
* Supports serializing the following:
  - Primitives (integers, strings, etc)
  - IP Addresses
  - BigDecimal
  - DateTime, Delta DateTimes
  - TimeSpan
  - Server.Race
  - Server.Map
  - Point2D, Point3D, Rect2D, Rect3D
  - Existing/New `ISerializable` references
  - Lists/Sets of serializable types
  - Type with a `Serialize` method and constructor that takes an `IGenericReader`
* Supports forward-only migration
* Supports existing RunUO deserialization for older versions by changing to the following signature:
  - `public void OldDeserialize(IGenericReader reader, int version)`
  - Must remove deserializing the version since this is already done
* Supports serializing from private fields or custom made properties.
* Types do not require inheriting Item/Mobile. Code gen will fully create `ISerializable` information.
  - This is not recommended yet, since it requires wiring to `Persistence` which will cause lots of unresolved symbol errors until code gen is built.

### Example
```cs
using System.Collections.Generic;

namespace Server.Items
{
    [Serializable(1)]
    public partial class TestItem1 : Item
    {
        [SerializableField(1)]
        [SerializableFieldAttr("[CommandProperty(AccessLevel.Administrator)]")]
        private List<Item> _someProperty;

        private void Deserialize(IGenericReader reader, int version)
        {
        }
    }
}
```

Generates this:
```cs
namespace Server.Items
{
    public partial class TestItem1
    {
#pragma warning disable 0414
        private const int _version = 1;
#pragma warning restore 0414

        [CommandProperty(AccessLevel.Administrator)]
        public System.Collections.Generic.List<Server.Item> SomeProperty
        {
            get => _someProperty;
            set
            {
                if (value != _someProperty)
                {
                    ((ISerializable)this).MarkDirty();
                    _someProperty = value;
                }
            }
        }

        public TestItem1(Serial serial) : base(serial)
        {
        }

        public override void Serialize(IGenericWriter writer)
        {
            var savePosition = ((Server.ISerializable)this).SavePosition;
            if (savePosition > -1)
            {
                writer.Seek(savePosition, System.IO.SeekOrigin.Begin);
                return;
            }
            writer.WriteEncodedInt(_version);
            writer.Write(_someProperty);
        }

        public override void Deserialize(IGenericReader reader)
        {
            var version = reader.ReadEncodedInt();
            if (version < 1)
            {
                OldDeserialize(reader, version);
                ((Server.ISerializable)this).MarkDirty();
                return;
            }
            SomeProperty = reader.ReadEntityList<Server.Item>();
        }
    }
}
```

And this:
```json
{
  "version": 1,
  "type": "TestItem1",
  "properties": [
    {
      "name": "SomeProperty",
      "type": "System.Collections.Generic.List\u003CServer.Item\u003E",
      "rule": "ListMigrationRule",
      "ruleArguments": [
        "Server.Item",
        "SerializableInterfaceMigrationRule"
      ]
    }
  ]
}
```

Projects/SerializationGenerator/SerializableMigration/ISerializableMigrationRule.cs

@@ -0,0 +1,46 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializableMigrationRule.cs                                    *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public interface ISerializableMigrationRule
+    {
+        string RuleName { get; }
+
+        bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        );
+
+        void GenerateDeserializationMethod(
+            StringBuilder source,
+            string indent,
+            SerializableProperty property
+        );
+
+        void GenerateSerializationMethod(
+            StringBuilder source,
+            string indent,
+            SerializableProperty property
+        );
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/ArrayMigrationRule.cs

@@ -0,0 +1,121 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: ArrayMigrationRule.cs                                           *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class ArrayMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(ArrayMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            if (symbol is not IArrayTypeSymbol arrayTypeSymbol)
+            {
+                ruleArguments = null;
+                return false;
+            }
+
+            var serializableArrayType = SerializableMigrationRulesEngine.GenerateSerializableProperty(
+                compilation,
+                "ArrayEntry",
+                arrayTypeSymbol.ElementType,
+                attributes,
+                serializableTypes
+            );
+
+            var length = serializableArrayType.RuleArguments.Length;
+            ruleArguments = new string[length + 2];
+            ruleArguments[0] = arrayTypeSymbol.ElementType.ToDisplayString();
+            ruleArguments[1] = serializableArrayType.Rule;
+            Array.Copy(serializableArrayType.RuleArguments, 0, ruleArguments, 2, length);
+
+            return true;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(ArrayMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+            var ruleArguments = property.RuleArguments;
+            var arrayElementRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var arrayElementRuleArguments = new string[ruleArguments.Length - 2];
+            Array.Copy(ruleArguments, 2, arrayElementRuleArguments, 0, ruleArguments.Length - 2);
+
+            var propertyIndex = $"{property.Name}Index";
+            source.AppendLine($"{indent}{property.Name} = new {ruleArguments[0]}[reader.ReadEncodedInt()];");
+            source.AppendLine($"{indent}for (var {propertyIndex} = 0; {propertyIndex} < {property.Name}.Length; {propertyIndex}++)");
+            source.AppendLine($"{indent}{{");
+
+            var serializableArrayElement = new SerializableProperty
+            {
+                Name = $"{property.Name}[{propertyIndex}]",
+                Type = ruleArguments[0],
+                Rule = arrayElementRule.RuleName,
+                RuleArguments = arrayElementRuleArguments
+            };
+
+            arrayElementRule.GenerateDeserializationMethod(source, $"{indent}    ", serializableArrayElement);
+
+            source.AppendLine($"{indent}}}");
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(ArrayMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var ruleArguments = property.RuleArguments;
+            var arrayElementRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var arrayElementRuleArguments = new string[ruleArguments.Length - 2];
+            Array.Copy(ruleArguments, 2, arrayElementRuleArguments, 0, ruleArguments.Length - 2);
+
+            var propertyIndex = $"{property.Name}Index";
+            source.AppendLine($"{indent}writer.WriteEncodedInt({property.Name}.Length);");
+            source.AppendLine($"{indent}for (var {propertyIndex} = 0; {propertyIndex} < {property.Name}.Length; {propertyIndex}++)");
+            source.AppendLine($"{indent}{{");
+
+            var serializableArrayElement = new SerializableProperty
+            {
+                Name = $"{property.Name}[{propertyIndex}]",
+                Type = ruleArguments[0],
+                Rule = arrayElementRule.RuleName,
+                RuleArguments = arrayElementRuleArguments
+            };
+
+            arrayElementRule.GenerateSerializationMethod(source, $"{indent}    ", serializableArrayElement);
+
+            source.AppendLine($"{indent}}}");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/HashSetMigrationRule.cs

@@ -0,0 +1,134 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: HashSetMigrationRule.cs                                         *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class HashSetMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(HashSetMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            if (symbol is not INamedTypeSymbol namedTypeSymbol || !symbol.IsHashSet(compilation))
+            {
+                ruleArguments = null;
+                return false;
+            }
+
+            var setTypeSymbol = namedTypeSymbol.TypeArguments[0];
+
+            var serializableSetType = SerializableMigrationRulesEngine.GenerateSerializableProperty(
+                compilation,
+                "SetEntry",
+                setTypeSymbol,
+                attributes,
+                serializableTypes
+            );
+
+            var length = serializableSetType.RuleArguments.Length;
+            ruleArguments = new string[length + 2];
+            ruleArguments[0] = setTypeSymbol.ToDisplayString();
+            ruleArguments[1] = serializableSetType.Rule;
+            Array.Copy(serializableSetType.RuleArguments, 0, ruleArguments, 2, length);
+
+            return true;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(HashSetMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var ruleArguments = property.RuleArguments;
+            var setElementRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var setElementRuleArguments = new string[ruleArguments.Length - 2];
+            Array.Copy(ruleArguments, 2, setElementRuleArguments, 0, ruleArguments.Length - 2);
+
+            var propertyName = property.Name;
+            var propertyVarPrefix = $"{char.ToLower(propertyName[0])}{propertyName.Substring(1, propertyName.Length - 1)}";
+            var propertyIndex = $"{propertyVarPrefix}Index";
+            var propertyEntry = $"{propertyVarPrefix}Entry";
+            var propertyCount = $"{propertyVarPrefix}Count";
+
+            source.AppendLine($"{indent}{ruleArguments[0]} {propertyEntry};");
+            source.AppendLine($"{indent}var {propertyCount} = reader.ReadEncodedInt();");
+            source.AppendLine($"{indent}{property.Name} = new System.Collections.Generic.HashSet<{ruleArguments[0]}>({propertyCount});");
+            source.AppendLine($"{indent}for (var {propertyIndex} = 0; i < {propertyCount}; {propertyIndex}++)");
+            source.AppendLine($"{indent}{{");
+
+            var serializableSetElement = new SerializableProperty
+            {
+                Name = propertyEntry,
+                Type = ruleArguments[0],
+                Rule = setElementRule.RuleName,
+                RuleArguments = setElementRuleArguments
+            };
+
+            setElementRule.GenerateDeserializationMethod(source, $"{indent}    ", serializableSetElement);
+            source.AppendLine($"{indent}    {property.Name}.Add({propertyEntry});");
+
+            source.AppendLine($"{indent}}}");
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(HashSetMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var ruleArguments = property.RuleArguments;
+            var setElementRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var setElementRuleArguments = new string[ruleArguments.Length - 2];
+            Array.Copy(ruleArguments, 2, setElementRuleArguments, 0, ruleArguments.Length - 2);
+
+            var propertyName = property.Name;
+            var propertyVarPrefix = $"{char.ToLower(propertyName[0])}{propertyName.Substring(1, propertyName.Length - 1)}";
+            var propertyEntry = $"{propertyVarPrefix}Entry";
+            source.AppendLine($"{indent}writer.WriteEncodedInt({property.Name}.Count);");
+            source.AppendLine($"{indent}foreach (var {propertyEntry} in {property.Name});");
+            source.AppendLine($"{indent}{{");
+
+            var serializableSetElement = new SerializableProperty
+            {
+                Name = propertyEntry,
+                Type = ruleArguments[0],
+                Rule = setElementRule.RuleName,
+                RuleArguments = setElementRuleArguments
+            };
+
+            setElementRule.GenerateSerializationMethod(source, $"{indent}    ", serializableSetElement);
+
+            source.AppendLine($"{indent}}}");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/KeyValuePairMigrationRule.cs

@@ -0,0 +1,179 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: KeyValuePairMigrationRule.cs                                    *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class KeyValuePairMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(KeyValuePairMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            if (symbol is not INamedTypeSymbol namedTypeSymbol || !symbol.IsKeyValuePair(compilation))
+            {
+                ruleArguments = null;
+                return false;
+            }
+
+            var typeArguments = namedTypeSymbol.TypeArguments;
+
+            var keySerializedProperty = SerializableMigrationRulesEngine.GenerateSerializableProperty(
+                compilation,
+                "key",
+                typeArguments[0],
+                attributes,
+                serializableTypes
+            );
+
+            var valueSerializedProperty = SerializableMigrationRulesEngine.GenerateSerializableProperty(
+                compilation,
+                "value",
+                typeArguments[1],
+                attributes,
+                serializableTypes
+            );
+
+            // Key
+            ruleArguments = new string[5 + keySerializedProperty.RuleArguments.Length + valueSerializedProperty.RuleArguments.Length];
+            ruleArguments[0] = typeArguments[0].ToDisplayString();
+            ruleArguments[1] = keySerializedProperty.Rule;
+            ruleArguments[2] = keySerializedProperty.RuleArguments.Length.ToString();
+            Array.Copy(keySerializedProperty.RuleArguments, 0, ruleArguments, 2, keySerializedProperty.RuleArguments.Length);
+
+            // Value
+            var valueIndex = 3 + keySerializedProperty.RuleArguments.Length;
+            ruleArguments[valueIndex++] = typeArguments[1].ToDisplayString();
+            ruleArguments[valueIndex++] = valueSerializedProperty.Rule;
+            Array.Copy(valueSerializedProperty.RuleArguments, 0, ruleArguments, valueIndex, valueSerializedProperty.RuleArguments.Length);
+
+            return true;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(KeyValuePairMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var ruleArguments = property.RuleArguments;
+            var keyType = ruleArguments[0];
+            var keyRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var keyRuleArguments = new string[int.Parse(ruleArguments[2])];
+            Array.Copy(ruleArguments, 3, keyRuleArguments, 0, keyRuleArguments.Length);
+
+            var serializableKeyProperty = new SerializableProperty
+            {
+                Name = "key",
+                Type = keyType,
+                Rule = keyRule.RuleName,
+                RuleArguments = keyRuleArguments
+            };
+
+            keyRule.GenerateDeserializationMethod(
+                source,
+                indent,
+                serializableKeyProperty
+            );
+
+            var valueIndex = 3 + keyRuleArguments.Length;
+            var valueType = ruleArguments[valueIndex++];
+            var valueRule = SerializableMigrationRulesEngine.Rules[ruleArguments[valueIndex++]];
+            var valueRuleArguments = new string[ruleArguments.Length - valueIndex];
+            Array.Copy(ruleArguments, valueIndex, valueRuleArguments, 0, valueRuleArguments.Length);
+
+            var serializableValueProperty = new SerializableProperty
+            {
+                Name = "value",
+                Type = valueType,
+                Rule = valueRule.RuleName,
+                RuleArguments = valueRuleArguments
+            };
+
+            keyRule.GenerateDeserializationMethod(
+                source,
+                indent,
+                serializableValueProperty
+            );
+
+            source.AppendLine(
+                $"{indent}{property.Name} = new {SerializableEntityGeneration.KEYVALUEPAIR_STRUCT}<{keyType}, {valueType}>(key, value);"
+            );
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(KeyValuePairMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var ruleArguments = property.RuleArguments;
+            var keyType = ruleArguments[0];
+            var keyRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var keyRuleArguments = new string[int.Parse(ruleArguments[2])];
+            Array.Copy(ruleArguments, 3, keyRuleArguments, 0, keyRuleArguments.Length);
+
+            var serializableKeyProperty = new SerializableProperty
+            {
+                Name = $"{property.Name}.Key",
+                Type = keyType,
+                Rule = keyRule.RuleName,
+                RuleArguments = keyRuleArguments
+            };
+
+            keyRule.GenerateSerializationMethod(
+                source,
+                indent,
+                serializableKeyProperty
+            );
+
+            var valueIndex = 3 + keyRuleArguments.Length;
+            var valueType = ruleArguments[valueIndex++];
+            var valueRule = SerializableMigrationRulesEngine.Rules[ruleArguments[valueIndex++]];
+            var valueRuleArguments = new string[ruleArguments.Length - valueIndex];
+            Array.Copy(ruleArguments, valueIndex, valueRuleArguments, 0, valueRuleArguments.Length);
+
+            var serializableValueProperty = new SerializableProperty
+            {
+                Name = $"{property.Name}.Value",
+                Type = valueType,
+                Rule = valueRule.RuleName,
+                RuleArguments = valueRuleArguments
+            };
+
+            keyRule.GenerateSerializationMethod(
+                source,
+                indent,
+                serializableValueProperty
+            );
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/ListMigrationRule.cs

@@ -0,0 +1,133 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: ListMigrationRule.cs                                            *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class ListMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(ListMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            if (symbol is not INamedTypeSymbol namedTypeSymbol || !symbol.IsList(compilation))
+            {
+                ruleArguments = null;
+                return false;
+            }
+
+            var listTypeSymbol = namedTypeSymbol.TypeArguments[0];
+
+            var serializableListType = SerializableMigrationRulesEngine.GenerateSerializableProperty(
+                compilation,
+                "ListEntry",
+                listTypeSymbol,
+                attributes,
+                serializableTypes
+            );
+
+            var length = serializableListType.RuleArguments.Length;
+            ruleArguments = new string[length + 2];
+            ruleArguments[0] = listTypeSymbol.ToDisplayString();
+            ruleArguments[1] = serializableListType.Rule;
+            Array.Copy(serializableListType.RuleArguments, 0, ruleArguments, 2, length);
+
+            return true;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(ListMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var ruleArguments = property.RuleArguments;
+            var listElementRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var listElementRuleArguments = new string[ruleArguments.Length - 2];
+            Array.Copy(ruleArguments, 2, listElementRuleArguments, 0, ruleArguments.Length - 2);
+
+            var propertyName = property.Name;
+            var propertyVarPrefix = $"{char.ToLower(propertyName[0])}{propertyName.Substring(1, propertyName.Length - 1)}";
+            var propertyIndex = $"{propertyVarPrefix}Index";
+            var propertyEntry = $"{propertyVarPrefix}Entry";
+            var propertyCount = $"{propertyVarPrefix}Count";
+
+            source.AppendLine($"{indent}{ruleArguments[0]} {propertyEntry};");
+            source.AppendLine($"{indent}var {propertyCount} = reader.ReadEncodedInt();");
+            source.AppendLine($"{indent}{propertyName} = new System.Collections.Generic.List<{ruleArguments[0]}>({propertyCount});");
+            source.AppendLine($"{indent}for (var {propertyIndex} = 0; {propertyIndex} < {propertyCount}; {propertyIndex}++)");
+            source.AppendLine($"{indent}{{");
+
+            var serializableListElement = new SerializableProperty
+            {
+                Name = propertyEntry,
+                Type = ruleArguments[0],
+                Rule = listElementRule.RuleName,
+                RuleArguments = listElementRuleArguments
+            };
+
+            listElementRule.GenerateDeserializationMethod(source, $"{indent}    ", serializableListElement);
+            source.AppendLine($"{indent}    {propertyName}.Add({propertyEntry});");
+
+            source.AppendLine($"{indent}}}");
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(ListMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var ruleArguments = property.RuleArguments;
+            var listElementRule = SerializableMigrationRulesEngine.Rules[ruleArguments[1]];
+            var listElementRuleArguments = new string[ruleArguments.Length - 2];
+            Array.Copy(ruleArguments, 2, listElementRuleArguments, 0, ruleArguments.Length - 2);
+
+            var propertyName = property.Name;
+            var propertyEntry = $"{char.ToLower(propertyName[0])}{propertyName.Substring(1, propertyName.Length - 1)}Entry";
+            source.AppendLine($"{indent}writer.WriteEncodedInt({propertyName}.Count);");
+            source.AppendLine($"{indent}foreach (var {propertyEntry} in {propertyName})");
+            source.AppendLine($"{indent}{{");
+
+            var serializableListElement = new SerializableProperty
+            {
+                Name = propertyEntry,
+                Type = ruleArguments[0],
+                Rule = listElementRule.RuleName,
+                RuleArguments = listElementRuleArguments
+            };
+
+            listElementRule.GenerateSerializationMethod(source, $"{indent}    ", serializableListElement);
+
+            source.AppendLine($"{indent}}}");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/PrimitiveTypeMigrationRule.cs

@@ -0,0 +1,159 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: PrimitiveTypeMigrationRule.cs                                   *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Linq;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class PrimitiveTypeMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(PrimitiveTypeMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            if (symbol.IsIpAddress(compilation))
+            {
+                ruleArguments = new[] { "IPAddress" };
+                return true;
+            }
+
+            if (symbol is not ITypeSymbol typeSymbol)
+            {
+                ruleArguments = null;
+                return false;
+            }
+
+            if (
+                typeSymbol.SpecialType is
+                    SpecialType.System_Boolean or
+                    SpecialType.System_SByte or
+                    SpecialType.System_Int16 or
+                    SpecialType.System_Int32 or
+                    SpecialType.System_Int64 or
+                    SpecialType.System_Byte or
+                    SpecialType.System_UInt16 or
+                    SpecialType.System_UInt32 or
+                    SpecialType.System_UInt64 or
+                    SpecialType.System_Single or
+                    SpecialType.System_Double or
+                    SpecialType.System_String or
+                    SpecialType.System_Decimal or
+                    SpecialType.System_DateTime
+            )
+            {
+                ruleArguments = new[] { typeSymbol.SpecialType.ToString() };
+                return true;
+            }
+
+            if (typeSymbol.SpecialType == SpecialType.System_DateTime)
+            {
+                ruleArguments = attributes.Any(a => a.IsDeltaDateTime(compilation))
+                    ? new[] { typeSymbol.SpecialType.ToString(), "DeltaTime" }
+                    : new[] { typeSymbol.SpecialType.ToString() };
+
+                return true;
+            }
+
+            ruleArguments = null;
+            return false;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(PrimitiveTypeMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            var ruleType = property.RuleArguments[0];
+            string readMethod;
+
+            if (ruleType == "IPAddress")
+            {
+                readMethod = "ReadIPAddress";
+            }
+            else
+            {
+                if (!Enum.TryParse<SpecialType>(ruleType, out var specialType))
+                {
+                    throw new ArgumentException($"Invalid rule state for property {propertyName} ({ruleType})");
+                }
+
+                readMethod = specialType switch
+                {
+                    SpecialType.System_Boolean => "ReadBool",
+                    SpecialType.System_SByte   => "ReadSByte",
+                    SpecialType.System_Int16   => "ReadShort",
+                    SpecialType.System_Int32   => "ReadInt",
+                    SpecialType.System_Int64   => "ReadLong",
+                    SpecialType.System_Byte    => "ReadByte",
+                    SpecialType.System_UInt16  => "ReadUShort",
+                    SpecialType.System_UInt32  => "ReadUInt",
+                    SpecialType.System_UInt64  => "ReadULong",
+                    SpecialType.System_Single  => "ReadFloat",
+                    SpecialType.System_Double  => "ReadDouble",
+                    SpecialType.System_String  => "ReadString",
+                    SpecialType.System_Decimal => "ReadDecimal",
+                    SpecialType.System_DateTime => property.RuleArguments.Length >= 2 &&
+                                                   property.RuleArguments[1] == "DeltaTime" ?
+                        "ReadDeltaTime" :
+                        "ReadDateTime"
+                };
+            }
+
+            source.AppendLine($"{indent}{propertyName} = reader.{readMethod}()");
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(PrimitiveTypeMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            var ruleType = property.RuleArguments[0];
+
+            if (!Enum.TryParse<SpecialType>(ruleType, out var specialType))
+            {
+                throw new ArgumentException($"Invalid rule state for property {propertyName} ({ruleType})");
+            }
+
+            if (specialType == SpecialType.System_DateTime && property.RuleArguments[1] == "DeltaTime")
+            {
+                source.AppendLine($"{indent}writer.WriteDeltaTime({propertyName});");
+            }
+            else
+            {
+                source.AppendLine($"{indent}writer.Write({propertyName});");
+            }
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/PrimitiveUOTypeMigrationRule.cs

@@ -0,0 +1,75 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: PrimitiveUOTypeMigrationRule.cs                                 *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class PrimitiveUOTypeMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(PrimitiveUOTypeMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            ruleArguments = symbol switch
+            {
+                _ when symbol.IsPoint2D(compilation)     => new[] { "Point2D" },
+                _ when symbol.IsPoint3D(compilation)     => new[] { "Point3D" },
+                _ when symbol.IsRectangle2D(compilation) => new[] { "Rect2D" },
+                _ when symbol.IsRectangle3D(compilation) => new[] { "Rect3D" },
+                _ when symbol.IsRace(compilation)        => new[] { "Race" },
+                _ when symbol.IsMap(compilation)         => new[] { "Map" },
+                _ => null
+            };
+
+            return ruleArguments != null;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(PrimitiveUOTypeMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            source.AppendLine($"{indent}{propertyName} = reader.Read{property.RuleArguments[0]}()");
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(PrimitiveUOTypeMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            source.AppendLine($"{indent}writer.Write({propertyName});");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/SerializableInterfaceMigrationRule.cs

@@ -0,0 +1,71 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializableInterfaceMigrationRule.cs                           *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class SerializableInterfaceMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(SerializableInterfaceMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            if (symbol is ITypeSymbol typeSymbol && typeSymbol.HasSerializableInterface(compilation, serializableTypes))
+            {
+                ruleArguments = Array.Empty<string>();
+                return true;
+            }
+
+            ruleArguments = null;
+            return false;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(SerializableInterfaceMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            source.AppendLine($"{indent}{propertyName} = reader.ReadEntity<{property.Type}>();");
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(SerializableInterfaceMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            source.AppendLine($"{indent}writer.Write({propertyName});");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/Rules/SerializationMethodSignatureMigrationRule.cs

@@ -0,0 +1,81 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializationMethodSignatureMigrationRule.cs                    *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public class SerializationMethodSignatureMigrationRule : ISerializableMigrationRule
+    {
+        public string RuleName => nameof(SerializationMethodSignatureMigrationRule);
+
+        public bool GenerateRuleState(
+            Compilation compilation,
+            ISymbol symbol,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes,
+            out string[] ruleArguments
+        )
+        {
+            if ((symbol as ITypeSymbol)?.HasPublicSerializeMethod(compilation, serializableTypes) != true)
+            {
+                ruleArguments = null;
+                return false;
+            }
+
+            if (symbol is not INamedTypeSymbol namedTypeSymbol ||
+                !namedTypeSymbol.HasGenericReaderCtor(compilation, out var requiresParent))
+            {
+                ruleArguments = null;
+                return false;
+            }
+
+            ruleArguments = requiresParent ? new[] { "DeserializationRequiresParent" } : Array.Empty<string>();
+            return true;
+        }
+
+        public void GenerateDeserializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(SerializationMethodSignatureMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            var argument = property.RuleArguments.Length >= 1 &&
+                           property.RuleArguments[0] == "DeserializationRequiresParent" ? ", this" : "";
+
+            source.AppendLine($"{indent}{propertyName} = new {property.Type}(reader{argument})");
+        }
+
+        public void GenerateSerializationMethod(StringBuilder source, string indent, SerializableProperty property)
+        {
+            const string expectedRule = nameof(SerializationMethodSignatureMigrationRule);
+            var ruleName = property.Rule;
+            if (expectedRule != ruleName)
+            {
+                throw new ArgumentException($"Invalid rule applied to property {ruleName}. Expecting {expectedRule}, but received {ruleName}.");
+            }
+
+            var propertyName = property.Name;
+            source.AppendLine($"{indent}{propertyName}.Serialize(writer);");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/SerializableMetadata.cs

@@ -0,0 +1,32 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializableMigration.cs                                        *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System.Collections.Generic;
+using System.Text.Json.Serialization;
+
+namespace SerializationGenerator
+{
+    public class SerializableMetadata
+    {
+        [JsonPropertyName("version")]
+        public int Version { get; set; }
+
+        [JsonPropertyName("type")]
+        public string Type { get; set; }
+
+        [JsonPropertyName("properties")]
+        public List<SerializableProperty> Properties { get; set; }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/SerializableMetadataComparer.cs

@@ -0,0 +1,27 @@
+using System.Collections.Generic;
+
+namespace SerializationGenerator
+{
+    public class SerializableMetadataComparer : IComparer<SerializableMetadata>
+    {
+        public int Compare(SerializableMetadata x, SerializableMetadata y)
+        {
+            if (ReferenceEquals(x, y))
+            {
+                return 0;
+            }
+
+            if (ReferenceEquals(null, y))
+            {
+                return 1;
+            }
+
+            if (ReferenceEquals(null, x))
+            {
+                return -1;
+            }
+
+            return x.Version.CompareTo(y.Version);
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/SerializableMigration.ContentStruct.cs

@@ -0,0 +1,53 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializableMigration.ContentStruct.cs                          *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System.Text;
+
+namespace SerializationGenerator
+{
+    public static partial class SerializableMigration
+    {
+        public static void GenerateMigrationContentStruct(
+            this StringBuilder source,
+            SerializableMetadata migration
+        )
+        {
+            const string indent = "        ";
+
+            source.AppendLine($"{indent}ref struct V{migration.Version}Content");
+            source.AppendLine($"{indent}{{");
+            foreach (var serializableProperty in migration.Properties)
+            {
+                source.AppendLine($"{indent}    internal readonly {serializableProperty.Type} {serializableProperty.Name};");
+            }
+
+            source.AppendLine($"{indent}    internal V{migration.Version}Content(IGenericReader reader)");
+            source.AppendLine($"{indent}    {{");
+
+            foreach (var serializableProperty in migration.Properties)
+            {
+                SerializableMigrationRulesEngine.Rules[serializableProperty.Rule].GenerateDeserializationMethod(
+                    source,
+                    $"{indent}        ",
+                    serializableProperty
+                );
+            }
+
+            source.AppendLine($"{indent}    }}");
+
+            source.AppendLine($"{indent}}}");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/SerializableMigration.cs

@@ -0,0 +1,78 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializableMigration.cs                                        *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Text.Json;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public static partial class SerializableMigration
+    {
+        public static JsonSerializerOptions GetJsonSerializerOptions(Compilation compilation) =>
+            new()
+            {
+                WriteIndented = true,
+                AllowTrailingCommas = true,
+                IgnoreNullValues = true,
+                ReadCommentHandling = JsonCommentHandling.Skip
+            };
+
+        public static string GetMigrationPath(GeneratorExecutionContext context)
+        {
+            context.AnalyzerConfigOptions.GlobalOptions.TryGetValue(
+                "build_property.SerializableMigrationPath",
+                out var migrationPath
+            );
+
+            return migrationPath;
+        }
+
+        public static List<SerializableMetadata> GetMigrations(
+            string migrationPath,
+            INamedTypeSymbol typeSymbol,
+            int version,
+            JsonSerializerOptions options
+        )
+        {
+            var typeName = typeSymbol.ToDisplayString();
+
+            var migrations = new SortedSet<SerializableMetadata>(new SerializableMetadataComparer());
+            var migrationFiles = Directory.GetFiles(migrationPath, $"{typeName}.v*.json");
+
+            foreach (var migrationFile in migrationFiles)
+            {
+                var text = File.ReadAllText(migrationFile, Encoding.UTF8);
+                var migration = JsonSerializer.Deserialize<SerializableMetadata>(text, options);
+                if (typeName == migration!.Type && version > migration.Version)
+                {
+                    migrations.Add(migration);
+                }
+            }
+
+            return migrations.ToList();
+        }
+
+        public static void WriteMigration(string migrationPath, SerializableMetadata metadata, JsonSerializerOptions options)
+        {
+            Directory.CreateDirectory(migrationPath);
+            var filePath = Path.Combine(migrationPath, $"{metadata.Type}.v{metadata.Version}.json");
+            File.WriteAllText(filePath, JsonSerializer.Serialize(metadata, options));
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/SerializableMigrationRulesEngine.cs

@@ -0,0 +1,78 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializableMigrationRulesEngine.cs                             *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using Microsoft.CodeAnalysis;
+
+namespace SerializationGenerator
+{
+    public static class SerializableMigrationRulesEngine
+    {
+        public static readonly Dictionary<string, ISerializableMigrationRule> Rules = new();
+
+        static SerializableMigrationRulesEngine()
+        {
+            var rules = new ISerializableMigrationRule[]
+            {
+                new ArrayMigrationRule(),
+                new HashSetMigrationRule(),
+                new KeyValuePairMigrationRule(),
+                new ListMigrationRule(),
+                new PrimitiveTypeMigrationRule(),
+                new PrimitiveUOTypeMigrationRule(),
+                new SerializableInterfaceMigrationRule(),
+                new SerializationMethodSignatureMigrationRule()
+            };
+
+            foreach (var rule in rules)
+            {
+                Rules.Add(rule.RuleName, rule);
+            }
+        }
+
+        public static SerializableProperty GenerateSerializableProperty(
+            Compilation compilation,
+            string propertyName,
+            ISymbol propertyType,
+            ImmutableArray<AttributeData> attributes,
+            ImmutableArray<INamedTypeSymbol> serializableTypes
+        )
+        {
+            foreach (var rule in Rules.Values)
+            {
+                if (rule.GenerateRuleState(
+                    compilation,
+                    propertyType,
+                    attributes,
+                    serializableTypes,
+                    out var ruleArguments
+                ))
+                {
+                    return new SerializableProperty
+                    {
+                        Name = propertyName,
+                        Type = propertyType.ToDisplayString(),
+                        Rule = rule.RuleName,
+                        RuleArguments = ruleArguments
+                    };
+                }
+            }
+
+            throw new Exception($"No rule found for property {propertyName} of type {propertyType} ({Rules.Count})");
+        }
+    }
+}

Projects/SerializationGenerator/SerializableMigration/SerializableProperty.cs

@@ -0,0 +1,34 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2021 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: SerializableProperty.cs                                         *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System.Text.Json.Serialization;
+
+namespace SerializationGenerator
+{
+    public class SerializableProperty
+    {
+        [JsonPropertyName("name")]
+        public string Name { get; init; }
+
+        [JsonPropertyName("type")]
+        public string Type { get; init; }
+
+        [JsonPropertyName("rule")]
+        public string Rule { get; init; }
+
+        [JsonPropertyName("ruleArguments")]
+        public string[] RuleArguments { get; init; }
+    }
+}