// 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.Collections.Immutable;
using System.Diagnostics;
using System.Threading;
 
namespace Microsoft.CodeAnalysis.CSharp.Symbols.PublicModel
{
    internal sealed class ParameterSymbol : Symbol, IParameterSymbol
    {
        private readonly Symbols.ParameterSymbol _underlying;
        private ITypeSymbol _lazyType;
 
        public ParameterSymbol(Symbols.ParameterSymbol underlying)
        {
            Debug.Assert(underlying is object);
            _underlying = underlying;
        }
 
        internal override CSharp.Symbol UnderlyingSymbol => _underlying;
 
        ITypeSymbol IParameterSymbol.Type
        {
            get
            {
                if (_lazyType is null)
                {
                    Interlocked.CompareExchange(ref _lazyType, _underlying.TypeWithAnnotations.GetPublicSymbol(), null);
                }
 
                return _lazyType;
            }
        }
 
        CodeAnalysis.NullableAnnotation IParameterSymbol.NullableAnnotation => _underlying.TypeWithAnnotations.ToPublicAnnotation();
 
        ImmutableArray<CustomModifier> IParameterSymbol.CustomModifiers
        {
            get { return _underlying.TypeWithAnnotations.CustomModifiers; }
        }
 
        ImmutableArray<CustomModifier> IParameterSymbol.RefCustomModifiers
        {
            get { return _underlying.RefCustomModifiers; }
        }
 
        IParameterSymbol IParameterSymbol.OriginalDefinition
        {
            get
            {
                return _underlying.OriginalDefinition.GetPublicSymbol();
            }
        }
 
        RefKind IParameterSymbol.RefKind => _underlying.RefKind;
 
        ScopedKind IParameterSymbol.ScopedKind => _underlying.EffectiveScope;
 
        bool IParameterSymbol.IsDiscard => _underlying.IsDiscard;
 
        bool IParameterSymbol.IsParams => _underlying.IsParams;
 
        bool IParameterSymbol.IsParamsArray => _underlying.IsParamsArray;
 
        bool IParameterSymbol.IsParamsCollection => _underlying.IsParamsCollection;
 
        bool IParameterSymbol.IsOptional => _underlying.IsOptional;
 
        bool IParameterSymbol.IsThis => _underlying.IsThis;
 
        int IParameterSymbol.Ordinal => _underlying.Ordinal;
 
        bool IParameterSymbol.HasExplicitDefaultValue => _underlying.HasExplicitDefaultValue;
 
        object IParameterSymbol.ExplicitDefaultValue => _underlying.ExplicitDefaultValue;
 
        #region ISymbol Members
 
        protected override void Accept(SymbolVisitor visitor)
        {
            visitor.VisitParameter(this);
        }
 
        protected override TResult Accept<TResult>(SymbolVisitor<TResult> visitor)
        {
            return visitor.VisitParameter(this);
        }
 
        protected override TResult Accept<TArgument, TResult>(SymbolVisitor<TArgument, TResult> visitor, TArgument argument)
        {
            return visitor.VisitParameter(this, argument);
        }
 
        #endregion
    }
}