// <copyright file="DefaultDateTimeConverter.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 for DateTime to handle default values.
    /// </summary>
    public class DefaultDateTimeConverter : JsonConverter<DateTime>
    {
        /// <summary>
        /// Reads and converts the JSON to DateTime, returning DateTime.MinValue for invalid or empty strings.
        /// </summary>
        /// <param name="reader">The Utf8JsonReader instance to read JSON tokens from.</param>
        /// <param name="typeToConvert">The target type to convert to (expected DateTime).</param>
        /// <param name="options">The serializer options that may affect parsing behavior.</param>
        /// <returns>The parsed DateTime value, or DateTime.MinValue when the input is null, empty, or invalid.</returns>
        public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
        {
            if (reader.TokenType == JsonTokenType.String)
            {
                string? str = reader.GetString();

                if (string.IsNullOrWhiteSpace(str))
                {
                    return DateTime.MinValue;
                }

                if (DateTime.TryParse(str, out var date))
                {
                    return date;
                }
            }

            return DateTime.MinValue;
        }

        /// <summary>
        /// Writes the DateTime value as a string in JSON.
        /// </summary>
        /// <param name="writer">The Utf8JsonWriter instance to write JSON tokens to.</param>
        /// <param name="value">The DateTime value to write.</param>
        /// <param name="options">The serializer options that may affect writing behavior.</param>
        public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
        {
            // Write DateTime in round-trip ISO 8601 format so JSON consumers can parse it reliably.
            writer.WriteStringValue(value.ToString("o"));
        }
    }
}