Preparation fo Mystery rolling

ALttPRandomizer/Serialization/YamlStringEnumConverter.cs

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+namespace ALttPRandomizer.Serialization {
+    using System;
+    using System.Collections.Generic;
+    using System.Reflection;
+    using System.Text.Json.Serialization;
+    using YamlDotNet.Core;
+    using YamlDotNet.Core.Events;
+    using YamlDotNet.Serialization;
+    using YamlDotNet.Serialization.NamingConventions;
+
+    public class YamlStringEnumConverter : IYamlTypeConverter {
+        private readonly Dictionary<Type, Dictionary<string, object>> deserializationMap;
+        private readonly Dictionary<Type, Dictionary<object, string>> serializationMap;
+
+        public YamlStringEnumConverter() {
+            this.deserializationMap = new();
+            this.serializationMap = new();
+        }
+
+        public bool Accepts(Type type) => type.IsEnum;
+
+        private void RegisterType(Type type) {
+            if (this.serializationMap.ContainsKey(type) && this.deserializationMap.ContainsKey(type)) {
+                return;
+            }
+
+            this.deserializationMap[type] = new();
+            this.serializationMap[type] = new();
+
+            var fields = type.GetFields(BindingFlags.Public | BindingFlags.Static);
+
+            foreach (var field in fields) {
+                var alias = UnderscoredNamingConvention.Instance.Apply(field.Name);
+                var value = Enum.Parse(type, field.Name);
+                var att = field.GetCustomAttribute<JsonStringEnumMemberNameAttribute>();
+                if (att != null) {
+                    alias = att.Name;
+                }
+
+                this.deserializationMap[type][alias] = value;
+                this.serializationMap[type][value] = alias;
+            }
+        }
+
+        public object? ReadYaml(IParser parser, Type type, ObjectDeserializer rootDeserializer) {
+            this.RegisterType(type);
+
+            var stringValue = parser.Consume<Scalar>().Value;
+
+            if (this.deserializationMap[type].TryGetValue(stringValue, out var value)) {
+                return value;
+            }
+
+            throw new YamlException($"Invalid value \"{stringValue}\" for type {type}");
+        }
+
+        public void WriteYaml(IEmitter emitter, object? value, Type type, ObjectSerializer serializer) {
+            this.RegisterType(type);
+
+            if (value is null) {
+                throw new YamlException($"Unexpected null value of type {type}");
+            }
+
+            if (this.serializationMap[type].TryGetValue(value, out var stringValue)) {
+                emitter.Emit(new Scalar(stringValue));
+                return;
+            }
+
+            throw new YamlException($"Invalid value \"{value}\" for type {type}");
+        }
+    }
+}