using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Runtime.Serialization.Formatters;

using System.IO;

using System.Data;

using System.ComponentModel.DataAnnotations;

using System.Globalization;

using System.Reflection;

using System.Collections.ObjectModel;

​

using System.Text.Json;

using System.Text.Json.Serialization;

​

using NUnit.Framework; // Throws NUnit.Framework.AssertionException

​

//https://stackoverflow.com/questions/68682450/automatic-conversion-of-numbers-to-bools-migrating-from-newtonsoft-to-system-t

​

    public record OutputState(bool Active);

​

    public class BoolConverter : JsonConverter<bool>

    {

        public override void Write(Utf8JsonWriter writer, bool value, JsonSerializerOptions options) =>

            writer.WriteBooleanValue(value);

        public override bool Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) =>

            reader.TokenType switch

            {

                JsonTokenType.True => true,

                JsonTokenType.False => false,

                JsonTokenType.String => bool.TryParse(reader.GetString(), out var b) ? b : throw new JsonException(),

                JsonTokenType.Number => reader.TryGetInt64(out long l) ? Convert.ToBoolean(l) : reader.TryGetDouble(out double d) ? Convert.ToBoolean(d) : false,

                _ => throw new JsonException(),

            };

    }

​

    // Copied from this answer https://stackoverflow.com/a/65025191/3744182

    // By https://stackoverflow.com/users/3744182/dbc

    // To https://stackoverflow.com/questions/65022834/how-to-deserialize-an-empty-string-to-a-null-value-for-all-nullablet-value-t

    public class NullableConverterFactory : JsonConverterFactory

    {

        static readonly byte [] Empty = Array.Empty<byte>();

​

        public override bool CanConvert(Type typeToConvert) => Nullable.GetUnderlyingType(typeToConvert) != null;

​

        public override JsonConverter CreateConverter(Type type, JsonSerializerOptions options) => 

            (JsonConverter)Activator.CreateInstance(

                typeof(NullableConverter<>).MakeGenericType(

                    new Type[] { Nullable.GetUnderlyingType(type) }),

                BindingFlags.Instance | BindingFlags.Public,

                binder: null,

                args: new object[] { options },

                culture: null);

​

        class NullableConverter<T> : JsonConverter<T?> where T : struct

        {

            // DO NOT CACHE the return of (JsonConverter<T>)options.GetConverter(typeof(T)) as DoubleConverter.Read() and DoubleConverter.Write()

            // DO NOT WORK for nondefault values of JsonSerializerOptions.NumberHandling which was introduced in .NET 5

            public NullableConverter(JsonSerializerOptions options) {} 

​

            public override T? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)

            {

                if (reader.TokenType == JsonTokenType.String)

                {

                    if (reader.ValueTextEquals(Empty))

                        return null;

                }

                return JsonSerializer.Deserialize<T>(ref reader, options);

            }           

​

            public override void Write(Utf8JsonWriter writer, T? value, JsonSerializerOptions options) =>

                JsonSerializer.Serialize(writer, value.Value, options);

        }

    }

    class TestClass

    {

        public static void Test()

        {

            Console.WriteLine();

​

            Test("true");

            Test("false");

            Test("True");

            Test("False");

​

            Test("\"True\"");

            Test("\"False\"");

            Test("\"TRUE\"");

            Test("\"FALSE\"");

            Test("\"true\"");

            Test("\"false\"");

            Test("\"\"");

            Test("\"   \"");

            Test("null");

            Console.WriteLine();

            Test("0");

            Test("1");

            Test("2");

            Test("1.1");

            Test("-1");

            Test("111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111");

            Test("11111111111111111111111111111111111111111111111111111111111111111111111111111111111");

            Test("11111111111111111111111111111111111111111111111111111111111111111111111111111111111.0");

            Test("111111111111111111111111111111111111111111111111111111111111111111111111111111111112222222222222222222.0");

            Test("0.000000");

            Test("0.00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001");

            Test("4.94065645841247E-324");

            Test("4.94065645841247E-326");

            Test("1.7976931348623157E+308");

            Test("1.7976931348623157E+309");

        }

        static void Test(string boolValue)

        {

            Console.Write("Testing {0}... ", boolValue);

            var data = string.Format("{{ \"Active\": {0} }}", boolValue);

            var output = TestRecord(data);

            TestNullable(boolValue);

            Console.WriteLine("Results consistent: {0}", output == null ? "Failed" : output?.ToString());

        }

        static bool? TestRecord(string data)

        {

            OutputState systemResult = null;

            OutputState newtonsoftResult = null;

            try

            {

                var options = new JsonSerializerOptions

                {

                    Converters = { new BoolConverter(), new NullableConverterFactory() },

                };

                var s1 = System.Text.Json.JsonSerializer.Deserialize<OutputState>(data, options);

                //Console.WriteLine($"OutputState 1: {s1.Active}");

                systemResult = s1;

            }

            catch (Exception ex)

            {

                //Console.WriteLine($"System.Text.Json failed: {ex.Message}");

            }

​

            try

            {

                var s2 = Newtonsoft.Json.JsonConvert.DeserializeObject<OutputState>(data);

                //Console.WriteLine($"OutputState 2: {s2.Active}");

                newtonsoftResult = s2;

            }

            catch (Exception ex)

            {

                //Console.WriteLine($"Newtonsoft.Json failed: {ex.Message}");

            }

            Assert.AreEqual(newtonsoftResult?.Active, systemResult?.Active, "newtonsoftResult?.Active == systemResult?.Active");

            return systemResult?.Active;

        }

        static bool? TestNullable(string boolValue)

        {

            (bool succeeded, bool? result) systemResult;

            (bool succeeded, bool? result) newtonsoftResult;

​

            try

            {

                var options = new JsonSerializerOptions

                {

                    Converters = { new BoolConverter(), new NullableConverterFactory() },

                };

                var s1 = System.Text.Json.JsonSerializer.Deserialize<bool?>(boolValue, options);

                //Console.WriteLine($"OutputState 1: {s1.Active}");

                systemResult = (true, s1);

            }

            catch (Exception ex)

            {

                systemResult = (false, null);

                Console.WriteLine($"System.Text.Json failed: {ex.Message}");

            }

​

            try

            {

                var s2 = Newtonsoft.Json.JsonConvert.DeserializeObject<bool?>(boolValue);

                //Console.WriteLine($"OutputState 2: {s2.Active}");

                newtonsoftResult = (true, s2);

            }

            catch (Exception ex)

            {

                newtonsoftResult = (false, null);

                Console.WriteLine($"Newtonsoft.Json failed: {ex.Message}");

            }

            Assert.AreEqual(newtonsoftResult, systemResult, $"{systemResult} == systemResult");

            return newtonsoftResult.result;

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: {0} ({1})", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , GetNetCoreVersion());

            Console.WriteLine("System.Text.Json version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

        public static string GetNetCoreVersion()

        {

            //https://techblog.dorogin.com/how-to-detect-net-core-version-in-runtime-ecd65ad695be

            //

            var assembly = typeof(System.Runtime.GCSettings).GetTypeInfo().Assembly;

            var assemblyPath = assembly.Location.Split(new[] { '/', '\\' }, StringSplitOptions.RemoveEmptyEntries);

            int netCoreAppIndex = Array.IndexOf(assemblyPath, "Microsoft.NETCore.App");

            if (netCoreAppIndex > 0 && netCoreAppIndex < assemblyPath.Length - 2)

                return assemblyPath[netCoreAppIndex + 1];

            return "";

        }

    }

​