// 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.Mef
{
    /// <summary>
    /// Use this attribute to declare a <see cref="IDynamicFileInfoProvider"/> implementation for MEF
    /// </summary>
    [MetadataAttribute]
    [AttributeUsage(AttributeTargets.Class)]
    internal class ExportDynamicFileInfoProviderAttribute : ExportAttribute
    {
        /// <summary>
        /// file extensions this <see cref="IDynamicFileInfoProvider"/> can handle such as cshtml
        /// 
        /// match will be done by <see cref="StringComparer.OrdinalIgnoreCase"/>
        /// </summary>
        public IEnumerable<string> Extensions { get; }
 
        public ExportDynamicFileInfoProviderAttribute(params string[] extensions)
            : base(typeof(IDynamicFileInfoProvider))
        {
            if (extensions?.Length == 0)
            {
                throw new ArgumentException(nameof(extensions));
            }
 
            Extensions = extensions;
        }
    }
}