// 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.Collections.Generic;
using System.Collections.Immutable;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
 
namespace Microsoft.CodeAnalysis.FindSymbols.Finders
{
    internal class EventSymbolReferenceFinder : AbstractMethodOrPropertyOrEventSymbolReferenceFinder<IEventSymbol>
    {
        protected override bool CanFind(IEventSymbol symbol)
            => true;
 
        protected sealed override ValueTask<ImmutableArray<ISymbol>> DetermineCascadedSymbolsAsync(
            IEventSymbol symbol,
            Solution solution,
            FindReferencesSearchOptions options,
            CancellationToken cancellationToken)
        {
            var backingFields = symbol.ContainingType.GetMembers()
                                                     .OfType<IFieldSymbol>()
                                                     .Where(f => symbol.Equals(f.AssociatedSymbol))
                                                     .ToImmutableArray<ISymbol>();
 
            var associatedNamedTypes = symbol.ContainingType.GetTypeMembers()
                                                            .WhereAsArray(n => symbol.Equals(n.AssociatedSymbol))
                                                            .CastArray<ISymbol>();
 
            return new(backingFields.Concat(associatedNamedTypes));
        }
 
        protected sealed override async Task<ImmutableArray<Document>> DetermineDocumentsToSearchAsync(
            IEventSymbol symbol,
            HashSet<string>? globalAliases,
            Project project,
            IImmutableSet<Document>? documents,
            FindReferencesSearchOptions options,
            CancellationToken cancellationToken)
        {
            var documentsWithName = await FindDocumentsAsync(project, documents, cancellationToken, symbol.Name).ConfigureAwait(false);
            var documentsWithGlobalAttributes = await FindDocumentsWithGlobalSuppressMessageAttributeAsync(project, documents, cancellationToken).ConfigureAwait(false);
            return documentsWithName.Concat(documentsWithGlobalAttributes);
        }
 
        protected sealed override ValueTask<ImmutableArray<FinderLocation>> FindReferencesInDocumentAsync(
            IEventSymbol symbol,
            FindReferencesDocumentState state,
            FindReferencesSearchOptions options,
            CancellationToken cancellationToken)
        {
            return FindReferencesInDocumentUsingSymbolNameAsync(symbol, state, cancellationToken);
        }
    }
}