fix: use custom discriminator

Model/IWhen.cs

@@ -1,6 +1,6 @@
 using YamlDotNet.Core;
 using YamlDotNet.Core.Events;
-using YamlDotNet.Serialization;
+using YamlDotNet.Serialization.BufferedDeserialization.TypeDiscriminators;
 
 namespace TimePasses.Model;
 
@@ -11,35 +11,28 @@ public interface IWhen {
     bool IsValid(Plugin plugin);
 }
 
-public class WhenConverter : IYamlTypeConverter {
-    public bool Accepts(Type type) {
-        // FIXME? typeof(IWhen).IsAssignableFrom(type)
-        return typeof(IWhen) == type;
-    }
+public class WhenDiscriminator : ITypeDiscriminator {
+    public Type BaseType => typeof(IWhen);
 
-    public object? ReadYaml(IParser parser, Type type) {
-        parser.Consume<MappingStart>();
-        var name = parser.Consume<Scalar>();
+    public bool TryDiscriminate(IParser buffer, out Type? suggestedType) {
+        buffer.Consume<MappingStart>();
+        var name = buffer.Consume<Scalar>();
         if (!name.IsKey) {
-            throw new YamlException("invalid when: missing key");
+            suggestedType = null;
+            return false;
         }
 
-        IWhen when;
         switch (name.Value) {
             case "quest": {
-                when = Plugin.Deserializer.Deserialize<WhenQuest>(parser);
+                suggestedType = typeof(WhenQuest);
                 break;
             }
             default: {
-                throw new YamlException($"invalid when: unknown type {name.Value}");
+                suggestedType = null;
+                return false;
             }
         }
 
-        parser.Consume<MappingEnd>();
-        return when;
-    }
-
-    public void WriteYaml(IEmitter emitter, object? value, Type type) {
-        throw new NotImplementedException();
+        return true;
     }
 }

Plugin.cs

@@ -29,11 +29,7 @@ public class Plugin : IDalamudPlugin {
         .WithNamingConvention(UnderscoredNamingConvention.Instance)
         // .WithTypeConverter(new WhenConverter())
         .WithTypeDiscriminatingNodeDeserializer(o => {
-            var keyMappings = new Dictionary<string, Type> {
-                ["quest"] = typeof(WhenQuest),
-            };
-
-            o.AddUniqueKeyTypeDiscriminator<IWhen>(keyMappings);
+            o.AddTypeDiscriminator(new WhenDiscriminator());
         })
         .Build();