// 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.Diagnostics;
using System.Runtime.InteropServices;
using Microsoft.CodeAnalysis;
using Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.Collections;
using Microsoft.VisualStudio.LanguageServices.Implementation.Interop;
using Microsoft.VisualStudio.LanguageServices.Implementation.Utilities;
 
namespace Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.InternalElements;
 
[ComVisible(true)]
[ComDefaultInterface(typeof(EnvDTE80.CodeFunction2))]
public sealed partial class CodeAccessorFunction : AbstractCodeElement, EnvDTE.CodeFunction, EnvDTE80.CodeFunction2
{
    internal static EnvDTE.CodeFunction Create(CodeModelState state, AbstractCodeMember parent, MethodKind kind)
    {
        var newElement = new CodeAccessorFunction(state, parent, kind);
        return (EnvDTE.CodeFunction)ComAggregate.CreateAggregatedObject(newElement);
    }
 
    private readonly ParentHandle<AbstractCodeMember> _parentHandle;
    private readonly MethodKind _kind;
 
    private CodeAccessorFunction(CodeModelState state, AbstractCodeMember parent, MethodKind kind)
        : base(state, parent.FileCodeModel)
    {
        Debug.Assert(kind is MethodKind.EventAdd or
                     MethodKind.EventRaise or
                     MethodKind.EventRemove or
                     MethodKind.PropertyGet or
                     MethodKind.PropertySet);
 
        _parentHandle = new ParentHandle<AbstractCodeMember>(parent);
        _kind = kind;
    }
 
    private AbstractCodeMember ParentMember => _parentHandle.Value;
 
    private bool IsPropertyAccessor()
        => _kind is MethodKind.PropertyGet or MethodKind.PropertySet;
 
    internal override bool TryLookupNode(out SyntaxNode node)
    {
        node = null;
 
        var parentNode = _parentHandle.Value.LookupNode();
        if (parentNode == null)
        {
            return false;
        }
 
        return CodeModelService.TryGetAutoPropertyExpressionBody(parentNode, out node) ||
               CodeModelService.TryGetAccessorNode(parentNode, _kind, out node);
    }
 
    public override EnvDTE.vsCMElement Kind
        => EnvDTE.vsCMElement.vsCMElementFunction;
 
    public override object Parent => _parentHandle.Value;
 
    public override EnvDTE.CodeElements Children
        => EmptyCollection.Create(this.State, this);
 
    protected override string GetName()
        => this.ParentMember.Name;
 
    protected override void SetName(string value)
        => this.ParentMember.Name = value;
 
    protected override string GetFullName()
        => this.ParentMember.FullName;
 
    public EnvDTE.CodeElements Attributes
        => AttributeCollection.Create(this.State, this);
 
    public EnvDTE.vsCMAccess Access
    {
        get
        {
            var node = LookupNode();
            return CodeModelService.GetAccess(node);
        }
 
        set
        {
            UpdateNode(FileCodeModel.UpdateAccess, value);
        }
    }
 
    public bool CanOverride
    {
        get
        {
            throw new System.NotImplementedException();
        }
 
        set
        {
            throw new System.NotImplementedException();
        }
    }
 
    public string Comment
    {
        get
        {
            throw Exceptions.ThrowEFail();
        }
 
        set
        {
            throw Exceptions.ThrowEFail();
        }
    }
 
    public string DocComment
    {
        get
        {
            return string.Empty;
        }
 
        set
        {
            throw Exceptions.ThrowENotImpl();
        }
    }
 
    public EnvDTE.vsCMFunction FunctionKind
    {
        get
        {
            if (LookupSymbol() is not IMethodSymbol methodSymbol)
            {
                throw Exceptions.ThrowEUnexpected();
            }
 
            return CodeModelService.GetFunctionKind(methodSymbol);
        }
    }
 
    public bool IsGeneric
    {
        get
        {
            if (IsPropertyAccessor())
            {
                return ((CodeProperty)this.ParentMember).IsGeneric;
            }
            else
            {
                return ((CodeEvent)this.ParentMember).IsGeneric;
            }
        }
    }
 
    public EnvDTE80.vsCMOverrideKind OverrideKind
    {
        get
        {
            if (IsPropertyAccessor())
            {
                return ((CodeProperty)this.ParentMember).OverrideKind;
            }
            else
            {
                return ((CodeEvent)this.ParentMember).OverrideKind;
            }
        }
 
        set
        {
            if (IsPropertyAccessor())
            {
                ((CodeProperty)this.ParentMember).OverrideKind = value;
            }
            else
            {
                ((CodeEvent)this.ParentMember).OverrideKind = value;
            }
        }
    }
 
    public bool IsOverloaded => false;
 
    public bool IsShared
    {
        get
        {
            if (IsPropertyAccessor())
            {
                return ((CodeProperty)this.ParentMember).IsShared;
            }
            else
            {
                return ((CodeEvent)this.ParentMember).IsShared;
            }
        }
 
        set
        {
            if (IsPropertyAccessor())
            {
                ((CodeProperty)this.ParentMember).IsShared = value;
            }
            else
            {
                ((CodeEvent)this.ParentMember).IsShared = value;
            }
        }
    }
 
    public bool MustImplement
    {
        get
        {
            if (IsPropertyAccessor())
            {
                return ((CodeProperty)this.ParentMember).MustImplement;
            }
            else
            {
                return ((CodeEvent)this.ParentMember).MustImplement;
            }
        }
 
        set
        {
            if (IsPropertyAccessor())
            {
                ((CodeProperty)this.ParentMember).MustImplement = value;
            }
            else
            {
                ((CodeEvent)this.ParentMember).MustImplement = value;
            }
        }
    }
 
    public EnvDTE.CodeElements Overloads
        => throw Exceptions.ThrowEFail();
 
    public EnvDTE.CodeElements Parameters
    {
        get
        {
            if (IsPropertyAccessor())
            {
                return ((CodeProperty)this.ParentMember).Parameters;
            }
 
            throw Exceptions.ThrowEFail();
        }
    }
 
    public EnvDTE.CodeTypeRef Type
    {
        get
        {
            if (IsPropertyAccessor())
            {
                return ((CodeProperty)this.ParentMember).Type;
            }
 
            throw Exceptions.ThrowEFail();
        }
 
        set
        {
            throw Exceptions.ThrowEFail();
        }
    }
 
    public EnvDTE.CodeAttribute AddAttribute(string name, string value, object position)
    {
        // TODO(DustinCa): Check VB
        throw Exceptions.ThrowEFail();
    }
 
    public EnvDTE.CodeParameter AddParameter(string name, object type, object position)
    {
        // TODO(DustinCa): Check VB
        throw Exceptions.ThrowEFail();
    }
 
    public void RemoveParameter(object element)
    {
        // TODO(DustinCa): Check VB
        throw Exceptions.ThrowEFail();
    }
}