SmartFlagEnumNameResolver.cs

using System;
using global::Utf8Json;
using global::Utf8Json.Formatters;

namespace Ardalis.SmartEnum.Utf8Json;

/// <summary>
/// 
/// </summary>
public class SmartFlagEnumNameResolver : IJsonFormatterResolver
{
    /// <summary>
    /// 
    /// </summary>
    public static readonly SmartFlagEnumNameResolver Instance = new SmartFlagEnumNameResolver();

    private SmartFlagEnumNameResolver()
    {
    }

    /// <summary>
    /// 
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <returns></returns>
    public IJsonFormatter<T> GetFormatter<T>() =>
        FormatterCache<T>.Formatter;

    private static class FormatterCache<T>
    {
        public static readonly IJsonFormatter<T> Formatter;

#pragma warning disable S3963 // "static" fields should be initialized inline
        static FormatterCache()
        {
            if (typeof(T).IsSmartFlagEnum(out var genericArguments))
            {
                var formatterType = typeof(SmartFlagEnumNameFormatter<,>).MakeGenericType(genericArguments);
                Formatter = (IJsonFormatter<T>)Activator.CreateInstance(formatterType);
            }
        }
#pragma warning restore S3963 // "static" fields should be initialized inline
    }
}