MoShiro/backend/fleet/src/Fleet.Core/StringId.cs

using System.Text.Json;
using System.Text.Json.Serialization;

namespace Fleet.Core;

/// <summary>节点 ID（带类型前缀的 ULID）。MoShiro 中的 AgentId 就是 NodeId。</summary>
[JsonConverter(typeof(NodeIdJsonConverter))]
public readonly record struct NodeId(string Value)
{
    public override string ToString() => Value;
}

/// <summary>强类型字符串 ID 的 JSON 转换器基类（源生成友好，不使用反射）。</summary>
public abstract class StringIdJsonConverter<TId> : JsonConverter<TId>
{
    protected abstract TId Create(string value);

    protected abstract string GetValue(TId id);

    public sealed override TId Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) =>
        Create(reader.GetString() ?? throw new JsonException("id must be a string"));

    public sealed override void Write(Utf8JsonWriter writer, TId value, JsonSerializerOptions options) =>
        writer.WriteStringValue(GetValue(value));

    public sealed override TId ReadAsPropertyName(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) =>
        Create(reader.GetString() ?? throw new JsonException("id must be a string"));

    public sealed override void WriteAsPropertyName(Utf8JsonWriter writer, TId value, JsonSerializerOptions options) =>
        writer.WritePropertyName(GetValue(value));
}

public sealed class NodeIdJsonConverter : StringIdJsonConverter<NodeId>
{
    protected override NodeId Create(string value) => new(value);

    protected override string GetValue(NodeId id) => id.Value;
}