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

namespace Pal.Client.Net;

public sealed class JwtDateConverter : JsonConverter<DateTimeOffset>
{
    static readonly DateTimeOffset Zero = new(1970, 1, 1, 0, 0, 0, TimeSpan.Zero);

    public override DateTimeOffset Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
    {
        if (reader.TokenType != JsonTokenType.Number)
            throw new JsonException("bad token type");

        return Zero.AddSeconds(reader.GetInt64());
    }

    public override void Write(Utf8JsonWriter writer, DateTimeOffset value, JsonSerializerOptions options) => throw new NotImplementedException();
}