using System;
using System.Collections.Generic;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace Questionable.Model.Common.Converter;

public sealed class StringListOrValueConverter : JsonConverter<List<string>>
{
	public override List<string> Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
	{
		if (reader.TokenType == JsonTokenType.String)
		{
			return new List<string>(1) { reader.GetString() };
		}
		if (reader.TokenType != JsonTokenType.StartArray)
		{
			throw new JsonException();
		}
		reader.Read();
		List<string> list = new List<string>();
		while (reader.TokenType != JsonTokenType.EndArray)
		{
			list.Add(reader.GetString());
			reader.Read();
		}
		return list;
	}

	public override void Write(Utf8JsonWriter writer, List<string>? value, JsonSerializerOptions options)
	{
		if (value == null)
		{
			writer.WriteNullValue();
			return;
		}
		if (value.Count == 1)
		{
			writer.WriteStringValue(value[0]);
			return;
		}
		writer.WriteStartArray();
		foreach (string item in value)
		{
			writer.WriteStringValue(item);
		}
		writer.WriteEndArray();
	}
}