using AutoMapper;
using DigitalData.MessagingService.Application.EmailAccount.Queries;
using DigitalData.MessagingService.Domain.Exceptions;
using DigitalData.MessagingService.Abstraction;
using MediatR;

namespace DigitalData.MessagingService.Application.EmailSending.Commands;

/// <summary>
/// Command to send an email (enqueue to RabbitMQ)
/// </summary>
public record SendEmailCommand : IRequest<OutgoingEmailEvent>
{
    public required GetSenderQuery Sender { get; init; }

    /// <summary>
    /// Recipient email addresses
    /// </summary>
    public required IEnumerable<string> Recipients { get; init; }

    /// <summary>
    /// Email subject
    /// </summary>
    public required string Subject { get; init; }

    /// <summary>
    /// Email body (HTML or plain text)
    /// </summary>
    public required string Body { get; init; }

    /// <summary>
    /// Is HTML email (default: true)
    /// </summary>
    public bool IsHtml { get; init; } = true;
}

/// <summary>
/// Handler for SendEmailCommand
/// Resolves the sender account via MediatR, maps to OutgoingEmailEvent and enqueues to RabbitMQ
/// </summary>
public class SendEmailCommandHandler(
ISender Sender,
IOutgoingEmailPublisher Publisher,
IMapper Mapper) : IRequestHandler<SendEmailCommand, OutgoingEmailEvent>
{
    public async Task<OutgoingEmailEvent> Handle(SendEmailCommand request, CancellationToken cancellationToken)
    {
        var senderAccount = await Sender.Send(request.Sender, cancellationToken)
            ?? throw new NotFoundException(
                $"No email account found for the given sender criteria (Id: {request.Sender.Id}, Username: {request.Sender.Username}).");

        var outgoingEmailEvent = Mapper.Map<OutgoingEmailEvent>(request) with { Sender = senderAccount };

        // Enqueue to RabbitMQ
        await Publisher.EnqueueAsync(outgoingEmailEvent, cancellationToken);
        return outgoingEmailEvent;
    }
}