using Newtonsoft.Json;
using JsonSerializer = Newtonsoft.Json.JsonSerializer;

namespace MasstransferCommon.Convert;

public class DatetimeConverter : JsonConverter<DateTime>
{
    private static readonly DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);

    public override void WriteJson(JsonWriter writer, DateTime value, JsonSerializer serializer)
    {
        long timestamp = (long)(value.ToUniversalTime() - UnixEpoch).TotalMilliseconds;
        writer.WriteValue(timestamp < 0 ? 0 : timestamp);
    }

    public override DateTime ReadJson(JsonReader reader, Type objectType, DateTime existingValue, bool hasExistingValue,
        JsonSerializer serializer)
    {
        var value = reader.Value;

        return long.TryParse(value + "", out var timestamp)
            ? UnixEpoch.AddMilliseconds(timestamp)
            : UnixEpoch.AddMilliseconds((long)value);
    }
}