// <copyright file="FloatArrayOrSingleConverter.cs" company="Smart Energia">
// Copyright (c) Smart Energia. All rights reserved.
// </copyright>

namespace Faturas
{
    using System;
    using System.Text.Json;
    using System.Text.Json.Serialization;

    /// <summary>
    /// Custom JSON converter to handle float arrays or single float values.
    /// </summary>
    public class FloatArrayOrSingleConverter : JsonConverter<float[]>
    {
        /// <summary>
        /// Reads and converts the JSON to either a float array or a single float value.
        /// </summary>
        /// <param name="reader">The reader to read from.</param>
        /// <param name="typeToConvert">The type to convert.</param>
        /// <param name="options">Serialization options.</param>
        /// <returns>The converted float array.</returns>
        /// <exception cref="JsonException">Thrown when the JSON token is not an array or a number.</exception>
        public override float[]? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
        {
            if (reader.TokenType == JsonTokenType.StartArray)
            {
                // Se for um array, desserializa como array de floats
                return JsonSerializer.Deserialize<float[]>(ref reader, options);
            }
            else if (reader.TokenType == JsonTokenType.Number)
            {
                // Se for um único valor, cria um array com esse valor
                return [reader.GetSingle()];
            }
            else
            {
                throw new JsonException($"Unexpected token {reader.TokenType} when parsing a float array or single float.");
            }
        }

        /// <summary>
        /// Writes the float array or single float value to JSON.
        /// </summary>
        /// <param name="writer">The writer to write to.</param>
        /// <param name="value">The float array value to write.</param>
        /// <param name="options">Serialization options.</param>
        public override void Write(Utf8JsonWriter writer, float[] value, JsonSerializerOptions options)
        {
            if (value.Length == 1)
            {
                // Se o array tiver apenas um valor, escreve como um único número
                writer.WriteNumberValue(value[0]);
            }
            else
            {
                // Se o array tiver múltiplos valores, escreve como array
                JsonSerializer.Serialize(writer, value, options);
            }
        }
    }
}