PortBlog.API/PortBlog.API/Services/MailService.cs

using AutoMapper;
using KBR.Shared.Mail;
using PortBlog.API.Common.Constants;
using PortBlog.API.Entities;
using PortBlog.API.Models;
using PortBlog.API.Repositories.Contracts;
using PortBlog.API.Services.Contracts;
using System.Net;
using System.Net.Mail;

namespace PortBlog.API.Services
{
    /// <summary>
    /// Provides functionality for sending emails and logging message activity.
    /// </summary>
    /// <remarks>
    /// Initializes a new instance of the <see cref="MailService"/> class.
    /// </remarks>
    /// <param name="configuration">The application configuration.</param>
    /// <param name="logger">The logger instance.</param>
    /// <param name="mailRepository">The mail repository for storing messages.</param>
    /// <param name="mapper">The AutoMapper instance.</param>
    public class MailService(IConfiguration configuration, ILogger<MailService> logger, IMailRepository mailRepository, IMapper mapper) : IMailService
    {

        /// <summary>
        /// Sends an email message asynchronously using the provided message details.
        /// </summary>
        /// <param name="messageSendDto">The message details to send.</param>
        /// <returns>A task representing the asynchronous operation.</returns>
        public async Task SendAsync(MessageSendDto messageSendDto)
        {
            logger.LogInformation("Sending message from {Name} ({FromEmail}).", messageSendDto.Name, messageSendDto.FromEmail);
            messageSendDto.Subject = $"Message from {messageSendDto.Name}: Portfolio";
            var messageEntity = mapper.Map<Message>(messageSendDto);
            try
            {
                var mailSettings = configuration.GetSection("MailSettings").Get<MailSettingsDto>();

                if (mailSettings != null && mailSettings.Enable)
                {
                    using (var client = new SmtpClient())
                    {
                        client.Host = mailSettings.Host;
                        client.Port = mailSettings.Port;
                        client.DeliveryMethod = SmtpDeliveryMethod.Network;
                        client.UseDefaultCredentials = false;
                        client.EnableSsl = true;
                        client.Credentials = new NetworkCredential(mailSettings.Email, mailSettings.Password);

                        using var mailMessage = new MailMessage(
                                from: new MailAddress(mailSettings.Email),
                                to: new MailAddress(MailHelpers.ReplaceEmailDomain(messageSendDto.ToEmail, mailSettings.Domain), messageSendDto.Name)
                        );

                        mailMessage.Subject = messageSendDto.Subject;
                        mailMessage.Body = messageSendDto.Content;
                        mailMessage.IsBodyHtml = true;

                        client.Send(mailMessage);
                        messageSendDto.SentStatus = (int)MailConstants.MailStatus.Success;
                    }

                    mailRepository.AddMessage(messageEntity);
                    await mailRepository.SaveChangesAsync();
                }
            }
            catch (Exception ex)
            {
                // Log full exception and persist failed message.
                logger.LogCritical(ex, "Exception while sending mail from {FromEmail} ({Name}).", messageSendDto.FromEmail, messageSendDto.Name);
                messageSendDto.SentStatus = (int)MailConstants.MailStatus.Failed;
                mailRepository.AddMessage(messageEntity);
                await mailRepository.SaveChangesAsync();

                // Throw a descriptive exception so callers can return an error message to the client.
                throw new InvalidOperationException($"Failed to send email to '{messageSendDto.ToEmail}'. See inner exception for details.", ex);
            }
        }
    }
}