// 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 Microsoft.CodeAnalysis.CodeGen;
using EmitContext = Microsoft.CodeAnalysis.Emit.EmitContext;
 
namespace Microsoft.Cci
{
    internal class ReturnValueParameter : IParameterDefinition
    {
        internal ReturnValueParameter(IMethodDefinition containingMethod)
        {
            _containingMethod = containingMethod;
        }
 
        bool IDefinition.IsEncDeleted => false;
 
        public IEnumerable<ICustomAttribute> GetAttributes(EmitContext context)
        {
            return _containingMethod.GetReturnValueAttributes(context);
        }
 
        public ISignature ContainingSignature
        {
            get { return _containingMethod; }
        }
 
        private readonly IMethodDefinition _containingMethod;
 
        public MetadataConstant? Constant
        {
            get { return null; }
        }
 
        public ImmutableArray<Cci.ICustomModifier> RefCustomModifiers
        {
            get { return _containingMethod.RefCustomModifiers; }
        }
 
        public ImmutableArray<Cci.ICustomModifier> CustomModifiers
        {
            get { return _containingMethod.ReturnValueCustomModifiers; }
        }
 
        public MetadataConstant? GetDefaultValue(EmitContext context)
        {
            return null;
        }
 
        public void Dispatch(MetadataVisitor visitor)
        {
        }
 
        public bool HasDefaultValue
        {
            get { return false; }
        }
 
        public ushort Index
        {
            get { return 0; }
        }
 
        public bool IsIn
        {
            get { return false; }
        }
 
        public bool IsByReference
        {
            get { return _containingMethod.ReturnValueIsByRef; }
        }
 
        public bool IsMarshalledExplicitly
        {
            get { return _containingMethod.ReturnValueIsMarshalledExplicitly; }
        }
 
        public bool IsOptional
        {
            get { return false; }
        }
 
        public bool IsOut
        {
            get { return false; }
        }
 
        public IMarshallingInformation MarshallingInformation
        {
            get { return _containingMethod.ReturnValueMarshallingInformation; }
        }
 
        public ImmutableArray<byte> MarshallingDescriptor
        {
            get { return _containingMethod.ReturnValueMarshallingDescriptor; }
        }
 
        public string Name
        {
            get { return string.Empty; }
        }
 
        public ITypeReference GetType(EmitContext context)
        {
            return _containingMethod.GetType(context);
        }
 
        public IDefinition AsDefinition(EmitContext context)
        {
            return this as IDefinition;
        }
 
        CodeAnalysis.Symbols.ISymbolInternal? Cci.IReference.GetInternalSymbol() => null;
 
        public sealed override bool Equals(object? obj)
        {
            // It is not supported to rely on default equality of these Cci objects, an explicit way to compare and hash them should be used.
            throw Roslyn.Utilities.ExceptionUtilities.Unreachable();
        }
 
        public sealed override int GetHashCode()
        {
            // It is not supported to rely on default equality of these Cci objects, an explicit way to compare and hash them should be used.
            throw Roslyn.Utilities.ExceptionUtilities.Unreachable();
        }
    }
}