// 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.Threading;
using System.Threading.Tasks;
using Roslyn.Utilities;
 
namespace Microsoft.CodeAnalysis.FindSymbols;
 
internal static partial class DependentTypeFinder
{
    private static Task<ImmutableArray<INamedTypeSymbol>> FindDerivedInterfacesInCurrentProcessAsync(
        INamedTypeSymbol type,
        Solution solution,
        IImmutableSet<Project>? projects,
        bool transitive,
        CancellationToken cancellationToken)
    {
        // Only an interface can be implemented.
        if (s_isInterface(type))
        {
            static bool TypeMatches(INamedTypeSymbol type, HashSet<INamedTypeSymbol> set)
                => s_isInterface(type) && TypeHasInterfaceInSet(type, set);
 
            return DescendInheritanceTreeAsync(type, solution, projects,
                typeMatches: TypeMatches,
                shouldContinueSearching: s_isInterface,
                transitive: transitive,
                cancellationToken: cancellationToken);
        }
 
        return SpecializedTasks.EmptyImmutableArray<INamedTypeSymbol>();
    }
}