// 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.
 
using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.Shared.Utilities;
 
namespace Microsoft.CodeAnalysis.FindSymbols
{
    /// <summary>
    /// A does-nothing version of the <see cref="IStreamingFindReferencesProgress"/>. Useful for
    /// clients that have no need to report progress as they work.
    /// </summary>
    internal class NoOpStreamingFindReferencesProgress : IStreamingFindReferencesProgress
    {
        public static readonly IStreamingFindReferencesProgress Instance =
            new NoOpStreamingFindReferencesProgress();
 
        public IStreamingProgressTracker ProgressTracker { get; } = new NoOpProgressTracker();
 
        private NoOpStreamingFindReferencesProgress()
        {
        }
 
        public ValueTask OnCompletedAsync(CancellationToken cancellationToken) => default;
        public ValueTask OnStartedAsync(CancellationToken cancellationToken) => default;
        public ValueTask OnDefinitionFoundAsync(SymbolGroup group, CancellationToken cancellationToken) => default;
        public ValueTask OnReferenceFoundAsync(SymbolGroup group, ISymbol symbol, ReferenceLocation location, CancellationToken cancellationToken) => default;
        public ValueTask OnFindInDocumentStartedAsync(Document document, CancellationToken cancellationToken) => default;
        public ValueTask OnFindInDocumentCompletedAsync(Document document, CancellationToken cancellationToken) => default;
 
        private class NoOpProgressTracker : IStreamingProgressTracker
        {
            public ValueTask AddItemsAsync(int count, CancellationToken cancellationToken) => default;
            public ValueTask ItemsCompletedAsync(int count, CancellationToken cancellationToken) => default;
        }
    }
}