using System;

namespace MediaBrowser.Common.Configuration
{
    /// <summary>
    /// A no-op <see cref="IConfigurationInvalidationBus"/> used by single-instance installs and whenever
    /// the shared bus is unavailable. Every instance keeps its own cached configuration, which is the
    /// behaviour of an install that has only one.
    /// </summary>
    public sealed class NullConfigurationInvalidationBus : IConfigurationInvalidationBus
    {
        /// <summary>
        /// Gets the shared instance.
        /// </summary>
        public static NullConfigurationInvalidationBus Instance { get; } = new NullConfigurationInvalidationBus();

        /// <inheritdoc />
        public void Publish(ConfigurationInvalidationScope scope, string? target)
        {
        }

        /// <inheritdoc />
        public void Subscribe(Action<ConfigurationInvalidation> handler)
        {
        }
    }
}