mmorales.photo/back/services/engine/mailing/EmailService.cs

using back.Options;
using Microsoft.Extensions.Options;
using System.Net;
using System.Net.Mail;

namespace back.services.engine.mailing;

public class EmailService(IOptions<MailServerOptions> options) : IEmailService
{
    public async Task SendEmailAsync(List<string> tos, string from, string subject, string body, Dictionary<string, object>? attachments = null, CancellationToken cancellationToken = default)
    {
        try 
        {
            await Parallel.ForEachAsync(tos, async (to, cancellationToken) => {
                await SendEmailAsync(to, from, subject, body, attachments, cancellationToken);
            });
        }
        catch (Exception ex)
        {
            // Log the exception or handle it as needed
            Console.WriteLine($"Error sending email to multiple recipients: {ex.Message}");
        }
    }
    public async Task SendEmailAsync(string to, string from, string subject, string body, Dictionary<string, object>? attachments = null, CancellationToken cancellationToken = default)
    {
        try 
        {
            using var message = new MailMessage();
            message.From = new MailAddress(from);
            message.To.Add(to);
            message.Subject = subject;
            message.Body = body;
            message.IsBodyHtml = true;
            message.Priority = MailPriority.Normal;
            message.DeliveryNotificationOptions = DeliveryNotificationOptions.Never;
            
            if (attachments != null)
            {
                foreach (var attachment in attachments)
                {
                    if (attachment.Value is FileStream fileStream)
                    {
                        message.Attachments.Add(new Attachment(fileStream, attachment.Key));
                    }
                    if (attachment.Value is string filePath && File.Exists(filePath))
                    {
                        message.Attachments.Add(new Attachment(filePath));
                    }
                }
            }

            using var cliente = new SmtpClient(options.Value.SmtpServer, options.Value.Puerto);
            cliente.UseDefaultCredentials = false;
            cliente.Credentials = new NetworkCredential(options.Value.Usuario, options.Value.Password);
            cliente.EnableSsl = options.Value.EnableSsl;
            cliente.DeliveryMethod = SmtpDeliveryMethod.Network;

            await cliente.SendMailAsync(message, cancellationToken);
        }
        catch (Exception ex)
        {
            // Log the exception or handle it as needed
            Console.WriteLine($"Error sending email: {ex.Message}");
        }
    }
}