// 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.Collections.Generic;
using System.Collections.Immutable;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CodeActions;
using Microsoft.CodeAnalysis.CodeRefactorings;
using Microsoft.CodeAnalysis.Diagnostics;
using Microsoft.CodeAnalysis.Editor.Implementation.RenameTracking;
using Microsoft.CodeAnalysis.Editor.Shared.Extensions;
using Microsoft.CodeAnalysis.Editor.Shared.Utilities;
using Microsoft.CodeAnalysis.Editor.UnitTests.Utilities;
using Microsoft.CodeAnalysis.Editor.UnitTests.Workspaces;
using Microsoft.CodeAnalysis.Notification;
using Microsoft.CodeAnalysis.Shared.TestHooks;
using Microsoft.CodeAnalysis.Shared.Utilities;
using Microsoft.CodeAnalysis.Text;
using Microsoft.CodeAnalysis.Text.Shared.Extensions;
using Microsoft.VisualStudio.Composition;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Editor;
using Microsoft.VisualStudio.Text.Editor.Commanding.Commands;
using Microsoft.VisualStudio.Text.Operations;
using Microsoft.VisualStudio.Text.Tagging;
using Roslyn.Test.Utilities;
using Roslyn.Utilities;
using Xunit;

namespace Microsoft.CodeAnalysis.Editor.UnitTests.RenameTracking
{
    internal sealed class RenameTrackingTestState : IDisposable
    {
        private readonly ITagger<RenameTrackingTag> _tagger;
        public readonly TestWorkspace Workspace;
        private readonly IWpfTextView _view;
        private readonly ITextUndoHistoryRegistry _historyRegistry;
        private string _notificationMessage = null;

        private readonly TestHostDocument _hostDocument;
        public TestHostDocument HostDocument { get { return _hostDocument; } }

        private readonly IEditorOperations _editorOperations;
        public IEditorOperations EditorOperations { get { return _editorOperations; } }

        private readonly MockRefactorNotifyService _mockRefactorNotifyService;
        public MockRefactorNotifyService RefactorNotifyService { get { return _mockRefactorNotifyService; } }

        private readonly RenameTrackingCodeRefactoringProvider _codeRefactoringProvider;
        private readonly RenameTrackingCancellationCommandHandler _commandHandler = new RenameTrackingCancellationCommandHandler();

        public static RenameTrackingTestState Create(
            string markup,
            string languageName,
            bool onBeforeGlobalSymbolRenamedReturnValue = true,
            bool onAfterGlobalSymbolRenamedReturnValue = true)
        {
            var workspace = CreateTestWorkspace(markup, languageName);
            return new RenameTrackingTestState(workspace, languageName, onBeforeGlobalSymbolRenamedReturnValue, onAfterGlobalSymbolRenamedReturnValue);
        }

        public static RenameTrackingTestState CreateFromWorkspaceXml(
            string workspaceXml,
            string languageName,
            bool onBeforeGlobalSymbolRenamedReturnValue = true,
            bool onAfterGlobalSymbolRenamedReturnValue = true)
        {
            var workspace = CreateTestWorkspace(workspaceXml);
            return new RenameTrackingTestState(workspace, languageName, onBeforeGlobalSymbolRenamedReturnValue, onAfterGlobalSymbolRenamedReturnValue);
        }

        public RenameTrackingTestState(
            TestWorkspace workspace,
            string languageName,
            bool onBeforeGlobalSymbolRenamedReturnValue = true,
            bool onAfterGlobalSymbolRenamedReturnValue = true)
        {
            this.Workspace = workspace;

            _hostDocument = Workspace.Documents.First();
            _view = _hostDocument.GetTextView();
            _view.Caret.MoveTo(new SnapshotPoint(_view.TextSnapshot, _hostDocument.CursorPosition.Value));
            _editorOperations = Workspace.GetService<IEditorOperationsFactoryService>().GetEditorOperations(_view);
            _historyRegistry = Workspace.ExportProvider.GetExport<ITextUndoHistoryRegistry>().Value;
            _mockRefactorNotifyService = new MockRefactorNotifyService
            {
                OnBeforeSymbolRenamedReturnValue = onBeforeGlobalSymbolRenamedReturnValue,
                OnAfterSymbolRenamedReturnValue = onAfterGlobalSymbolRenamedReturnValue
            };

            // Mock the action taken by the workspace INotificationService
            var notificationService = (INotificationServiceCallback)Workspace.Services.GetRequiredService<INotificationService>();
            var callback = new Action<string, string, NotificationSeverity>((message, title, severity) => _notificationMessage = message);
            notificationService.NotificationCallback = callback;

            var tracker = new RenameTrackingTaggerProvider(
                Workspace.ExportProvider.GetExportedValue<IThreadingContext>(),
                Workspace.ExportProvider.GetExport<IInlineRenameService>().Value,
                Workspace.ExportProvider.GetExport<IDiagnosticAnalyzerService>().Value,
                Workspace.ExportProvider.GetExportedValue<IAsynchronousOperationListenerProvider>());

            _tagger = tracker.CreateTagger<RenameTrackingTag>(_hostDocument.GetTextBuffer());

            if (languageName == LanguageNames.CSharp ||
                languageName == LanguageNames.VisualBasic)
            {
                _codeRefactoringProvider = new RenameTrackingCodeRefactoringProvider(
                    _historyRegistry,
                    SpecializedCollections.SingletonEnumerable(_mockRefactorNotifyService));
            }
            else
            {
                throw new ArgumentException("Invalid language name: " + languageName, nameof(languageName));
            }
        }

        private static TestWorkspace CreateTestWorkspace(string code, string languageName)
        {
            return CreateTestWorkspace(string.Format(@"
<Workspace>
    <Project Language=""{0}"" CommonReferences=""true"">
        <Document>{1}</Document>
    </Project>
</Workspace>", languageName, code));
        }

        private static TestWorkspace CreateTestWorkspace(string xml)
        {
            return TestWorkspace.Create(xml, composition: EditorTestCompositions.EditorFeaturesWpf);
        }

        public void SendEscape()
            => _commandHandler.ExecuteCommand(new EscapeKeyCommandArgs(_view, _view.TextBuffer), TestCommandExecutionContext.Create());

        public void MoveCaret(int delta)
        {
            var position = _view.Caret.Position.BufferPosition.Position;
            _view.Caret.MoveTo(new SnapshotPoint(_view.TextSnapshot, position + delta));
        }

        public void Undo(int count = 1)
        {
            var history = _historyRegistry.GetHistory(_view.TextBuffer);
            history.Undo(count);
        }

        public void Redo(int count = 1)
        {
            var history = _historyRegistry.GetHistory(_view.TextBuffer);
            history.Redo(count);
        }

        public async Task AssertNoTag()
        {
            await WaitForAsyncOperationsAsync();

            var tags = _tagger.GetTags(_view.TextBuffer.CurrentSnapshot.GetSnapshotSpanCollection());

            Assert.Equal(0, tags.Count());
        }

        /// <param name="textSpan">If <see langword="null"/> the current caret position will be used.</param>
        public async Task<CodeAction> TryGetCodeActionAsync(TextSpan? textSpan = null)
        {
            var span = textSpan ?? new TextSpan(_view.Caret.Position.BufferPosition, 0);

            var document = this.Workspace.CurrentSolution.GetDocument(_hostDocument.Id);

            var actions = new List<CodeAction>();
            var context = new CodeRefactoringContext(
                document, span, actions.Add, CancellationToken.None);
            await _codeRefactoringProvider.ComputeRefactoringsAsync(context);
            return actions.SingleOrDefault();
        }

        public async Task AssertTag(string expectedFromName, string expectedToName, bool invokeAction = false)
        {
            await WaitForAsyncOperationsAsync();

            var tags = _tagger.GetTags(_view.TextBuffer.CurrentSnapshot.GetSnapshotSpanCollection());

            // There should only ever be one tag
            Assert.Equal(1, tags.Count());

            var tag = tags.Single();

            // There should only be one code action for the tag
            var codeAction = await TryGetCodeActionAsync(tag.Span.Span.ToTextSpan());
            Assert.NotNull(codeAction);
            Assert.Equal(string.Format(EditorFeaturesResources.Rename_0_to_1, expectedFromName, expectedToName), codeAction.Title);

            if (invokeAction)
            {
                var operations = (await codeAction.GetOperationsAsync(CancellationToken.None)).ToArray();
                Assert.Equal(1, operations.Length);

                operations[0].TryApply(this.Workspace, new ProgressTracker(), CancellationToken.None);
            }
        }

        public void AssertNoNotificationMessage()
            => Assert.Null(_notificationMessage);

        public void AssertNotificationMessage()
            => Assert.NotNull(_notificationMessage);

        private async Task WaitForAsyncOperationsAsync()
        {
            var provider = Workspace.ExportProvider.GetExportedValue<AsynchronousOperationListenerProvider>();
            await provider.WaitAllDispatcherOperationAndTasksAsync(
                FeatureAttribute.RenameTracking,
                FeatureAttribute.SolutionCrawler,
                FeatureAttribute.Workspace,
                FeatureAttribute.EventHookup);
        }

        public void Dispose()
            => Workspace.Dispose();
    }
}