// 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;
using System.Composition;
using System.Threading;
using Microsoft.CodeAnalysis.CSharp.Extensions.ContextQuery;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.Editing;
using Microsoft.CodeAnalysis.Host.Mef;
using Microsoft.CodeAnalysis.Snippets;
using Microsoft.CodeAnalysis.Snippets.SnippetProviders;
 
namespace Microsoft.CodeAnalysis.CSharp.Snippets;
 
[ExportSnippetProvider(nameof(ISnippetProvider), LanguageNames.CSharp), Shared]
[method: ImportingConstructor]
[method: Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
internal sealed class CSharpPropgSnippetProvider() : AbstractCSharpAutoPropertySnippetProvider
{
    public override string Identifier => CommonSnippetIdentifiers.GetOnlyProperty;
 
    public override string Description => FeaturesResources.get_only_property;
 
    protected override AccessorDeclarationSyntax? GenerateSetAccessorDeclaration(CSharpSyntaxContext syntaxContext, SyntaxGenerator generator, CancellationToken cancellationToken)
    {
        // Interface cannot have properties with `private set` accessor.
        // So if we are inside an interface, we just return null here.
        // This causes the caller to just skip this `set` accessor
        if (syntaxContext.ContainingTypeDeclaration is InterfaceDeclarationSyntax)
        {
            return null;
        }
 
        // Having a property with `set` accessor in a readonly struct leads to a compiler error.
        // So if user executes snippet inside a readonly struct the right thing to do is to not generate `set` accessor at all
        if (syntaxContext.ContainingTypeDeclaration is StructDeclarationSyntax structDeclaration &&
            syntaxContext.SemanticModel.GetDeclaredSymbol(structDeclaration, cancellationToken) is { IsReadOnly: true })
        {
            return null;
        }
 
        return (AccessorDeclarationSyntax)generator.SetAccessorDeclaration(Accessibility.Private);
    }
}