using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

namespace Svrnty.CQRS.Events.Abstractions.Subscriptions;

/// <summary>
/// Manages the lifecycle of persistent subscriptions.
/// </summary>
public interface ISubscriptionManager
{
    /// <summary>
    /// Create a new subscription.
    /// </summary>
    Task<PersistentSubscription> CreateSubscriptionAsync(
        string subscriberId,
        string correlationId,
        HashSet<string>? eventTypes = null,
        HashSet<string>? terminalEventTypes = null,
        DeliveryMode deliveryMode = DeliveryMode.Immediate,
        DateTimeOffset? expiresAt = null,
        string? dataSourceId = null,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Get a subscription by ID.
    /// </summary>
    Task<PersistentSubscription?> GetSubscriptionAsync(
        string subscriptionId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Get all subscriptions for a subscriber.
    /// </summary>
    Task<IReadOnlyList<PersistentSubscription>> GetSubscriberSubscriptionsAsync(
        string subscriberId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Get all active subscriptions for a correlation ID.
    /// </summary>
    Task<IReadOnlyList<PersistentSubscription>> GetActiveSubscriptionsByCorrelationAsync(
        string correlationId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Mark an event as delivered to a subscription.
    /// Updates the LastDeliveredSequence and persists the change.
    /// </summary>
    Task MarkEventDeliveredAsync(
        string subscriptionId,
        long sequence,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Complete a subscription (terminal event received).
    /// </summary>
    Task CompleteSubscriptionAsync(
        string subscriptionId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Cancel a subscription (user-initiated).
    /// </summary>
    Task CancelSubscriptionAsync(
        string subscriptionId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Pause a subscription (temporarily stop event delivery).
    /// </summary>
    Task PauseSubscriptionAsync(
        string subscriptionId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Resume a paused subscription.
    /// </summary>
    Task ResumeSubscriptionAsync(
        string subscriptionId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Associate a subscription with a connection ID (client connected).
    /// </summary>
    Task AttachConnectionAsync(
        string subscriptionId,
        string connectionId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Disassociate a subscription from a connection ID (client disconnected).
    /// </summary>
    Task DetachConnectionAsync(
        string subscriptionId,
        CancellationToken cancellationToken = default);

    /// <summary>
    /// Clean up expired subscriptions.
    /// </summary>
    Task CleanupExpiredSubscriptionsAsync(
        CancellationToken cancellationToken = default);
}