// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
#nullable disable
 
using System;
using System.Collections.Generic;
using System.Composition;
 
namespace Microsoft.CodeAnalysis.Host;
 
[MetadataAttribute]
[AttributeUsage(AttributeTargets.Class)]
internal sealed class ExportEventListenerAttribute : ExportAttribute
{
    public string Service { get; }
    public IReadOnlyCollection<string> WorkspaceKinds { get; }
 
    /// <summary>
    /// MEF export attribute for <see cref="IEventListener"/>
    /// </summary>
    /// <param name="service">
    /// one of values from <see cref="WellKnownEventListeners"/> indicating which service this event listener is for
    /// </param>
    /// <param name="workspaceKinds">indicate which workspace kind this event listener is for</param>
    public ExportEventListenerAttribute(string service, params string[] workspaceKinds)
        : base(typeof(IEventListener))
    {
        if (workspaceKinds?.Length == 0)
        {
            throw new ArgumentNullException(nameof(workspaceKinds));
        }
 
        this.Service = service ?? throw new ArgumentNullException(nameof(service));
        this.WorkspaceKinds = workspaceKinds;
    }
}