// Copyright (c) 2023 Tudor Stanciu

using Correo.Abstractions;
using Correo.Abstractions.Extensions;
using Correo.SendGrid.Extensions;
using Correo.SendGrid.Models;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Newtonsoft.Json;
using SendGrid;
using System;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace Correo.SendGrid
{
    internal class SendGridService : IMailer
    {
        private readonly IOptions<SendGridOptions> _optionsAccessor;
        private readonly SendGridClient _client;
        private readonly ILogger<SendGridService> _logger;

        public SendGridService(IOptions<SendGridOptions> optionsAccessor, ILogger<SendGridService> logger)
        {
            _optionsAccessor = optionsAccessor;
            _logger = logger;
            _client = new SendGridClient(_optionsAccessor.Value.ApiKey);
        }

        public void SendEmail(EmailMessage message)
        {
            SendEmailAsync(message).GetAwaiter().GetResult();
        }

        public async Task SendEmailAsync(EmailMessage message, CancellationToken token = default)
        {
            var mailMessage = message.ToSendGridMessage();
            var response = await _client.SendEmailAsync(mailMessage, token);
            if (response.IsSuccessStatusCode)
                _logger.LogInformation(message.Log());
            else
            {
                var body = await response.DeserializeResponseBodyAsync();
                var found = body.TryGetValue("errors", out var jsonData);
                if (found)
                {
                    string errorsString = Convert.ToString(jsonData);
                    var errors = JsonConvert.DeserializeObject<Error[]>(errorsString);
                    var errorMessage = string.Join("; ", errors.Select(z => z.Message));
                    throw new Exception(errorMessage);
                }

                throw new Exception(response.StatusCode.ToString());
            }
        }
    }
}