using System;

namespace Svrnty.CQRS.Events.Abstractions.Configuration;

/// <summary>
/// Configuration for dead letter queue behavior.
/// </summary>
public class DeadLetterQueueConfiguration
{
    /// <summary>
    /// Gets or sets whether DLQ is enabled for this stream.
    /// </summary>
    public bool Enabled { get; set; }

    /// <summary>
    /// Gets or sets the name of the dead letter stream.
    /// If not specified, defaults to {StreamName}-dlq.
    /// </summary>
    public string? DeadLetterStreamName { get; set; }

    /// <summary>
    /// Gets or sets the maximum number of delivery attempts before sending to DLQ.
    /// </summary>
    public int MaxDeliveryAttempts { get; set; } = 3;

    /// <summary>
    /// Gets or sets the delay between retry attempts.
    /// </summary>
    public TimeSpan? RetryDelay { get; set; }

    /// <summary>
    /// Gets or sets whether to store the original event in the DLQ.
    /// </summary>
    public bool? StoreOriginalEvent { get; set; }

    /// <summary>
    /// Gets or sets whether to store error details in the DLQ.
    /// </summary>
    public bool? StoreErrorDetails { get; set; }

    /// <summary>
    /// Validates the DLQ configuration.
    /// </summary>
    /// <exception cref="ArgumentException">Thrown when configuration is invalid.</exception>
    public void Validate()
    {
        if (Enabled)
        {
            if (MaxDeliveryAttempts <= 0)
                throw new ArgumentException("MaxDeliveryAttempts must be positive", nameof(MaxDeliveryAttempts));

            if (RetryDelay.HasValue && RetryDelay.Value < TimeSpan.Zero)
                throw new ArgumentException("RetryDelay cannot be negative", nameof(RetryDelay));
        }
    }
}