// Copyright (c) .NET Foundation and contributors. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

using System.Collections.Generic;
using System.Collections.Immutable;
using Microsoft.CodeAnalysis;

namespace ILLink.RoslynAnalyzer
{
    internal sealed class ImmutableArrayOperations
    {
        internal static bool Contains<T, TComp>(ImmutableArray<T> list, T elem, TComp comparer)
                    where TComp : IEqualityComparer<T>
        {
            foreach (var e in list)
            {
                if (comparer.Equals(e, elem))
                {
                    return true;
                }
            }
            return false;
        }

        internal static TSymbol? TryGetSingleSymbol<TSymbol>(ImmutableArray<ISymbol> members) where TSymbol : class, ISymbol
        {
            TSymbol? candidate = null;
            foreach (var m in members)
            {
                if (m is TSymbol tsym)
                {
                    if (candidate is null)
                    {
                        candidate = tsym;
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            return candidate;
        }

        internal static void AddIfNotNull<TSymbol>(ImmutableArray<TSymbol>.Builder properties, TSymbol? p) where TSymbol : class, ISymbol
        {
            if (p != null)
            {
                properties.Add(p);
            }
        }
    }
}