using System;
using Svrnty.CQRS.Events.Subscriptions;
using System.Collections.Generic;

namespace Svrnty.CQRS.Events.Management;

/// <summary>
/// Information about an event stream for management API responses.
/// </summary>
public sealed record StreamInfo
{
    /// <summary>
    /// Name of the stream.
    /// </summary>
    public required string Name { get; init; }

    /// <summary>
    /// Stream type (Ephemeral or Persistent).
    /// </summary>
    public required string Type { get; init; }

    /// <summary>
    /// Delivery semantics (AtMostOnce, AtLeastOnce, ExactlyOnce).
    /// </summary>
    public required string DeliverySemantics { get; init; }

    /// <summary>
    /// Stream scope (Internal or CrossService).
    /// </summary>
    public required string Scope { get; init; }

    /// <summary>
    /// Current length of the stream (total events).
    /// </summary>
    public long Length { get; init; }

    /// <summary>
    /// Number of subscriptions on this stream.
    /// </summary>
    public int SubscriptionCount { get; init; }

    /// <summary>
    /// List of subscription IDs.
    /// </summary>
    public List<string> Subscriptions { get; init; } = new();
}

/// <summary>
/// Information about a subscription for management API responses.
/// </summary>
public sealed record SubscriptionInfo
{
    /// <summary>
    /// Unique subscription identifier.
    /// </summary>
    public required string SubscriptionId { get; init; }

    /// <summary>
    /// Name of the stream this subscription consumes from.
    /// </summary>
    public required string StreamName { get; init; }

    /// <summary>
    /// Subscription mode (Broadcast, Exclusive, ConsumerGroup).
    /// </summary>
    public required string Mode { get; init; }

    /// <summary>
    /// Whether the subscription is active.
    /// </summary>
    public bool IsActive { get; init; }

    /// <summary>
    /// When the subscription was created.
    /// </summary>
    public DateTimeOffset CreatedAt { get; init; }

    /// <summary>
    /// Visibility timeout for in-flight events.
    /// </summary>
    public TimeSpan VisibilityTimeout { get; init; }

    /// <summary>
    /// Whether automatic upcasting is enabled.
    /// </summary>
    public bool EnableUpcasting { get; init; }

    /// <summary>
    /// Target event version for upcasting (null = latest).
    /// </summary>
    public int? TargetEventVersion { get; init; }

    /// <summary>
    /// Optional description of the subscription.
    /// </summary>
    public string? Description { get; init; }
}

/// <summary>
/// Information about a consumer for management API responses.
/// </summary>
public sealed record ConsumerInfo
{
    /// <summary>
    /// Consumer ID.
    /// </summary>
    public required string ConsumerId { get; init; }

    /// <summary>
    /// Current offset (position in stream).
    /// </summary>
    public long Offset { get; init; }

    /// <summary>
    /// Number of events the consumer is behind the stream head.
    /// </summary>
    public long Lag { get; init; }

    /// <summary>
    /// Last time the consumer updated its offset.
    /// </summary>
    public DateTimeOffset LastUpdated { get; init; }

    /// <summary>
    /// Whether the consumer appears to be stalled (no progress).
    /// </summary>
    public bool IsStalled { get; init; }
}

/// <summary>
/// Request to reset a consumer's offset.
/// </summary>
public sealed record ResetOffsetRequest
{
    /// <summary>
    /// The new offset to set. Use 0 to reset to the beginning.
    /// Use -1 to set to the end (latest).
    /// </summary>
    public long NewOffset { get; init; }
}