// 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 System.Threading.Tasks;
using System.Windows;
using Microsoft.CodeAnalysis.Editor.Shared.Extensions;
using Microsoft.CodeAnalysis.Editor.Shared.Utilities;
using Microsoft.CodeAnalysis.Host.Mef;
using Microsoft.CodeAnalysis.Options;
using Microsoft.CodeAnalysis.Text;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Differencing;
using Microsoft.VisualStudio.Text.Editor;
using Microsoft.VisualStudio.Text.Operations;
using Microsoft.VisualStudio.Text.Projection;
using Microsoft.VisualStudio.Utilities;
 
namespace Microsoft.CodeAnalysis.Editor.Implementation.Preview;
 
[Export(typeof(IPreviewFactoryService)), Shared]
internal sealed class PreviewFactoryService : AbstractPreviewFactoryService<IWpfDifferenceViewer>
{
    private readonly IEditorOperationsFactoryService _editorOperationsFactoryService;
    private readonly IWpfDifferenceViewerFactoryService _differenceViewerService;
 
    [ImportingConstructor]
    [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
    public PreviewFactoryService(
        IThreadingContext threadingContext,
        ITextBufferFactoryService textBufferFactoryService,
        ITextBufferCloneService textBufferCloneService,
        IContentTypeRegistryService contentTypeRegistryService,
        IProjectionBufferFactoryService projectionBufferFactoryService,
        ITextEditorFactoryService textEditorFactoryService,
        EditorOptionsService editorOptionsService,
        ITextDifferencingSelectorService differenceSelectorService,
        IDifferenceBufferFactoryService differenceBufferService,
        IEditorOperationsFactoryService editorOperationsFactoryService,
        ITextDocumentFactoryService textDocumentFactoryService,
        IWpfDifferenceViewerFactoryService differenceViewerService)
        : base(threadingContext,
              textBufferFactoryService,
              textBufferCloneService,
              contentTypeRegistryService,
              projectionBufferFactoryService,
              editorOptionsService,
              differenceSelectorService,
              differenceBufferService,
              textDocumentFactoryService,
              textEditorFactoryService.CreateTextViewRoleSet(
                  TextViewRoles.PreviewRole, PredefinedTextViewRoles.Analyzable, PredefinedTextViewRoles.Interactive, PredefinedTextViewRoles.ChangePreview))
    {
        _editorOperationsFactoryService = editorOperationsFactoryService;
        _differenceViewerService = differenceViewerService;
    }
 
    protected override IDifferenceViewerPreview<IWpfDifferenceViewer> CreateDifferenceViewerPreview(IWpfDifferenceViewer viewer)
        => new DifferenceViewerPreview(viewer, _editorOperationsFactoryService);
 
    protected override async Task<IWpfDifferenceViewer> CreateDifferenceViewAsync(IDifferenceBuffer diffBuffer, ITextViewRoleSet previewRoleSet, DifferenceViewMode mode, double zoomLevel, CancellationToken cancellationToken)
    {
        var diffViewer = _differenceViewerService.CreateDifferenceView(diffBuffer, previewRoleSet);
 
        try
        {
            const string DiffOverviewMarginName = "deltadifferenceViewerOverview";
 
            diffViewer.ViewMode = mode;
 
            IWpfTextView view;
            IWpfTextViewHost host;
            if (mode == DifferenceViewMode.RightViewOnly)
            {
                view = diffViewer.RightView;
                host = diffViewer.RightHost;
            }
            else if (mode == DifferenceViewMode.LeftViewOnly)
            {
                view = diffViewer.LeftView;
                host = diffViewer.LeftHost;
            }
            else
            {
                Contract.ThrowIfFalse(mode == DifferenceViewMode.Inline);
                view = diffViewer.InlineView;
                host = diffViewer.InlineHost;
            }
 
            view.ZoomLevel *= zoomLevel;
            view.Options.SetOptionValue(DefaultTextViewHostOptions.HorizontalScrollBarId, false);
            view.Options.SetOptionValue(DefaultTextViewHostOptions.VerticalScrollBarId, false);
            view.Options.SetOptionValue(DefaultTextViewHostOptions.GlyphMarginId, false);
            view.Options.SetOptionValue(DefaultTextViewHostOptions.SelectionMarginId, false);
            view.Options.SetOptionValue(DefaultTextViewHostOptions.SuggestionMarginId, false);
 
            // Enable tab stop for the diff view host and collapse couple of unwanted margins.
            host.HostControl.IsTabStop = true;
            host.GetTextViewMargin(DiffOverviewMarginName).VisualElement.Visibility = Visibility.Collapsed;
            host.GetTextViewMargin(PredefinedMarginNames.Bottom).VisualElement.Visibility = Visibility.Collapsed;
 
            // Enable focus for the diff viewer.
            view.VisualElement.Focusable = true;
 
#pragma warning disable CA2007 // Consider calling ConfigureAwait on the awaited task (containing method uses JTF)
            await diffViewer.SizeToFitAsync(ThreadingContext, cancellationToken: cancellationToken);
#pragma warning restore CA2007 // Consider calling ConfigureAwait on the awaited task
 
            return diffViewer;
        }
        catch
        {
            diffViewer.Close();
            throw;
        }
    }
}