// 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 Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp;
using Microsoft.CodeAnalysis.Editor.Options;
using Microsoft.CodeAnalysis.Editor.Shared.Extensions;
using Microsoft.CodeAnalysis.Editor.Shared.Utilities;
using Microsoft.CodeAnalysis.Options;
using Microsoft.VisualStudio.Text.Editor.Commanding;
using Microsoft.VisualStudio.Text.Editor.Commanding.Commands;
 
namespace Microsoft.CodeAnalysis.Editor.CommandHandlers;
 
internal abstract class AbstractSignatureHelpCommandHandler
{
    protected readonly IThreadingContext ThreadingContext;
    private readonly SignatureHelpControllerProvider _controllerProvider;
    private readonly IGlobalOptionService _globalOptions;
 
    public AbstractSignatureHelpCommandHandler(
        IThreadingContext threadingContext,
        SignatureHelpControllerProvider controllerProvider,
        IGlobalOptionService globalOptions)
    {
        ThreadingContext = threadingContext;
        _controllerProvider = controllerProvider;
        _globalOptions = globalOptions;
    }
 
    protected bool TryGetController(EditorCommandArgs args, out Controller controller)
    {
        this.ThreadingContext.ThrowIfNotOnUIThread();
 
        // If args is `InvokeSignatureHelpCommandArgs` then sig help was explicitly invoked by the user and should
        // be shown whether or not the option is set.
        var languageName = args.SubjectBuffer.GetLanguageName();
        if (args is not InvokeSignatureHelpCommandArgs &&
            languageName != null &&
            !_globalOptions.GetOption(SignatureHelpViewOptionsStorage.ShowSignatureHelp, languageName))
        {
            controller = null;
            return false;
        }
 
        controller = _controllerProvider.GetController(args.TextView, args.SubjectBuffer);
        return controller is not null;
    }
}