[OneBot] Better LightApp parse (#666)

Lagrange.OneBot/Core/Entity/Common/LightApp.cs

@@ -1,4 +1,5 @@
 using System.Text.Json.Serialization;
+using Lagrange.OneBot.Core.Operation.Converters;
 
 namespace Lagrange.OneBot.Core.Entity.Common;
 #pragma warning disable CS8618
@@ -14,9 +15,9 @@ public class LightApp
 
     [JsonPropertyName("from")] public long From { get; set; }
 
-    [JsonPropertyName("meta")] public Meta Meta { get; set; }
+    [JsonPropertyName("meta")] [JsonConverter(typeof(NullIfEmptyConverter<Meta>))] public Meta Meta { get; set; }
 
-    [JsonPropertyName("extra")] public Extra? Extra { get; set; }
+    [JsonPropertyName("extra")] [JsonConverter(typeof(NullIfEmptyConverter<Extra>))] public Extra? Extra { get; set; }
 
     [JsonPropertyName("prompt")] public string Prompt { get; set; }
 

Lagrange.OneBot/Core/Operation/Converters/AutosizeConverter.cs

@@ -14,6 +14,7 @@ public override bool Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSer
             JsonTokenType.True => true,
             JsonTokenType.False => false,
             JsonTokenType.String when Utf8Parser.TryParse(reader.HasValueSequence ? reader.ValueSequence.ToArray() : reader.ValueSpan, out bool value, out _) => value,
+            JsonTokenType.String when Utf8Parser.TryParse(reader.HasValueSequence ? reader.ValueSequence.ToArray() : reader.ValueSpan, out int intValue, out _) => intValue != 0,
             JsonTokenType.Number when reader.TryGetInt32(out int val) => Convert.ToBoolean(val),
             _ => throw new JsonException()
         };

Lagrange.OneBot/Core/Operation/Converters/ForwardConverter.cs

@@ -0,0 +1,22 @@
+using System.Buffers;
+using System.Buffers.Text;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace Lagrange.OneBot.Core.Operation.Converters;
+
+public class ForwardConverter : JsonConverter<int>
+{
+    public override int Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        return reader.TokenType switch
+        {
+            JsonTokenType.True => 1,
+            JsonTokenType.False => 0, 
+            JsonTokenType.Number when reader.TryGetInt32(out int intValue) => intValue,
+            _ => throw new JsonException()
+        };
+    }
+
+    public override void Write(Utf8JsonWriter writer, int value, JsonSerializerOptions options) => writer.WriteNumberValue(value);
+}

Lagrange.OneBot/Core/Operation/Converters/NullIfEmptyConverter.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace Lagrange.OneBot.Core.Operation.Converters;
+
+public class NullIfEmptyConverter<T> : JsonConverter<T> where T : class
+{
+    public override T? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        return reader.TokenType switch
+        {
+            JsonTokenType.String when reader.ValueSpan.Length == 0 => null, 
+            JsonTokenType.StartObject => JsonSerializer.Deserialize<T>(ref reader, options),
+            _ => throw new JsonException()
+        };
+    }
+
+    public override void Write(Utf8JsonWriter writer, T? value, JsonSerializerOptions options) => JsonSerializer.Serialize(writer, value, options);
+}

Lagrange.OneBot/Message/Entity/LocationSegment.cs

@@ -24,7 +24,7 @@ public LocationSegment() : this(0f, 0f) { }
 [SegmentSubscriber(typeof(LightAppEntity), "location")]
 public partial class LocationSegment : SegmentBase
 {
-    private static readonly JsonSerializerOptions Options = new() { Converters = { new AutosizeConverter() }, DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull };
+    private static readonly JsonSerializerOptions Options = new() { Converters = { new AutosizeConverter(), new ForwardConverter() }, DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull };
 
     public override void Build(MessageBuilder builder, SegmentBase segment)
     {