using System;
using System.Diagnostics.CodeAnalysis;
using Newtonsoft.Json;

namespace Infrastructure.Functions
{

    [ExcludeFromCodeCoverage]
    public class NonEmptyStringConverter : JsonConverter
    {
        public override bool CanConvert(Type objectType) =>
            objectType == typeof(string);

        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
        {
            var stringValue = (string)value;
            writer.WriteValue(stringValue);
        }

        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
        {
            if (reader.TokenType != JsonToken.String)
            {
                throw CreateException($"Expected string value, but found {reader.TokenType}.", reader);
            }

            var stringValue = (string)reader.Value;

            if (string.IsNullOrWhiteSpace(stringValue))
            {
                throw CreateException("Non-empty string required.", reader);
            }

            return stringValue;
        }

        private static Exception CreateException(string message, JsonReader reader)
        {
            var info = (IJsonLineInfo)reader;

            return new JsonSerializationException($"{message} Path: '{reader.Path}', Line: {info.LineNumber}");
        }
    }
}