DigitalData.MessagingService/src/DigitalData.EmailProfiler.Application/Interfaces/Services/IEmailQueue.cs

using DigitalData.EmailProfiler.Domain.Entities;

namespace DigitalData.EmailProfiler.Application.Interfaces.Services;

/// <summary>
/// Email queue interface for asynchronous email sending.
/// Current implementation: In-memory Channel&lt;T&gt;
/// Future: RabbitMQ (see agents.md)
/// </summary>
public interface IEmailQueue
{
    /// <summary>
    /// Enqueue an email for sending.
    /// </summary>
    Task EnqueueAsync(EmailOutbox email, CancellationToken cancellationToken = default);

    /// <summary>
    /// Dequeue an email for sending.
    /// Returns null if queue is empty.
    /// </summary>
    Task<EmailOutbox?> DequeueAsync(CancellationToken cancellationToken = default);

    /// <summary>
    /// Get current queue depth (number of pending emails).
    /// </summary>
    Task<int> GetQueueDepthAsync(CancellationToken cancellationToken = default);
}