// 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;
using System.Linq;
using Microsoft.CodeAnalysis.Editor.UnitTests.CodeActions;
using Microsoft.CodeAnalysis.Editor.UnitTests.Utilities;
using Microsoft.CodeAnalysis.Test.Utilities;
using Microsoft.VisualStudio.Commanding;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Editor;
using Microsoft.VisualStudio.Text.Editor.Commanding.Commands;
using Microsoft.VisualStudio.Text.Operations;
using Roslyn.Test.Utilities;
using Xunit;
 
namespace Microsoft.CodeAnalysis.Editor.UnitTests.DocumentationComments;
 
[UseExportProvider]
public abstract class AbstractDocumentationCommentTests
{
    protected abstract char DocumentationCommentCharacter { get; }
 
    internal abstract ICommandHandler CreateCommandHandler(EditorTestWorkspace workspace);
 
    protected abstract EditorTestWorkspace CreateTestWorkspace(string code);
 
    internal void VerifyTypingCharacter(string initialMarkup, string expectedMarkup, bool useTabs = false, string newLine = "\r\n", bool trimTrailingWhiteSpace = false, OptionsCollection globalOptions = null)
    {
        Verify(initialMarkup, expectedMarkup,
            execute: (workspace, view, editorOperationsFactoryService) =>
            {
                var commandHandler = CreateCommandHandler(workspace);
 
                var commandArgs = new TypeCharCommandArgs(view, view.TextBuffer, DocumentationCommentCharacter);
                var nextHandler = CreateInsertTextHandler(view, DocumentationCommentCharacter.ToString());
 
                commandHandler.ExecuteCommand(commandArgs, nextHandler, TestCommandExecutionContext.Create());
            },
            useTabs, newLine, trimTrailingWhiteSpace, globalOptions);
    }
 
    internal void VerifyPressingEnter(string initialMarkup, string expectedMarkup, bool useTabs = false, string newLine = "\r\n", bool trimTrailingWhiteSpace = false, OptionsCollection globalOptions = null)
    {
        Verify(initialMarkup, expectedMarkup,
            execute: (workspace, view, editorOperationsFactoryService) =>
            {
                var commandHandler = CreateCommandHandler(workspace);
 
                var commandArgs = new ReturnKeyCommandArgs(view, view.TextBuffer);
                var nextHandler = CreateInsertTextHandler(view, "\r\n");
                commandHandler.ExecuteCommand(commandArgs, nextHandler, TestCommandExecutionContext.Create());
            },
            useTabs, newLine, trimTrailingWhiteSpace, globalOptions);
    }
 
    internal void VerifyInsertCommentCommand(string initialMarkup, string expectedMarkup, bool useTabs = false, string newLine = "\r\n", bool trimTrailingWhiteSpace = false, OptionsCollection globalOptions = null)
    {
        Verify(initialMarkup, expectedMarkup,
            execute: (workspace, view, editorOperationsFactoryService) =>
            {
                var commandHandler = CreateCommandHandler(workspace);
 
                var commandArgs = new InsertCommentCommandArgs(view, view.TextBuffer);
                Action nextHandler = delegate { };
 
                commandHandler.ExecuteCommand(commandArgs, nextHandler, TestCommandExecutionContext.Create());
            },
            useTabs, newLine, trimTrailingWhiteSpace, globalOptions);
    }
 
    internal void VerifyOpenLineAbove(string initialMarkup, string expectedMarkup, bool useTabs = false, string newLine = "\r\n", bool trimTrailingWhiteSpace = false, OptionsCollection globalOptions = null)
    {
        Verify(initialMarkup, expectedMarkup,
            execute: (workspace, view, editorOperationsFactoryService) =>
            {
                var commandHandler = CreateCommandHandler(workspace);
 
                var commandArgs = new OpenLineAboveCommandArgs(view, view.TextBuffer);
                void nextHandler()
                {
                    var editorOperations = editorOperationsFactoryService.GetEditorOperations(view);
                    editorOperations.OpenLineAbove();
                }
 
                commandHandler.ExecuteCommand(commandArgs, nextHandler, TestCommandExecutionContext.Create());
            },
            useTabs, newLine, trimTrailingWhiteSpace, globalOptions);
    }
 
    internal void VerifyOpenLineBelow(string initialMarkup, string expectedMarkup, bool useTabs = false, string newLine = "\r\n", bool trimTrailingWhiteSpace = false, OptionsCollection globalOptions = null)
    {
        Verify(initialMarkup, expectedMarkup,
            execute: (workspace, view, editorOperationsFactoryService) =>
            {
                var commandHandler = CreateCommandHandler(workspace);
 
                var commandArgs = new OpenLineBelowCommandArgs(view, view.TextBuffer);
                void nextHandler()
                {
                    var editorOperations = editorOperationsFactoryService.GetEditorOperations(view);
                    editorOperations.OpenLineBelow();
                }
 
                commandHandler.ExecuteCommand(commandArgs, nextHandler, TestCommandExecutionContext.Create());
            },
            useTabs, newLine, trimTrailingWhiteSpace, globalOptions);
    }
 
    private static Action CreateInsertTextHandler(ITextView textView, string text)
    {
        return () =>
        {
            var caretPosition = textView.Caret.Position.BufferPosition;
            var newSpanshot = textView.TextBuffer.Insert(caretPosition, text);
            textView.Caret.MoveTo(new SnapshotPoint(newSpanshot, caretPosition + text.Length));
        };
    }
 
    private void Verify(
        string initialMarkup,
        string expectedMarkup,
        Action<EditorTestWorkspace, IWpfTextView, IEditorOperationsFactoryService> execute,
        bool useTabs,
        string newLine,
        bool trimTrailingWhiteSpace,
        OptionsCollection globalOptions)
    {
        using var workspace = CreateTestWorkspace(initialMarkup);
        var testDocument = workspace.Documents.Single();
 
        Assert.True(testDocument.CursorPosition.HasValue, "No caret position set!");
        var startCaretPosition = testDocument.CursorPosition.Value;
 
        var view = testDocument.GetTextView();
 
        globalOptions?.SetGlobalOptions(workspace.GlobalOptions);
 
        var optionsFactory = workspace.GetService<IEditorOptionsFactoryService>();
        var editorOptions = optionsFactory.GetOptions(view.TextBuffer);
        editorOptions.SetOptionValue(DefaultOptions.ConvertTabsToSpacesOptionId, !useTabs);
        editorOptions.SetOptionValue(DefaultOptions.NewLineCharacterOptionId, newLine);
        view.Options.SetOptionValue(DefaultOptions.TrimTrailingWhiteSpaceOptionId, trimTrailingWhiteSpace);
 
        if (testDocument.SelectedSpans.Any())
        {
            var selectedSpan = testDocument.SelectedSpans[0];
            var isReversed = selectedSpan.Start == startCaretPosition;
 
            view.Selection.Select(new SnapshotSpan(view.TextSnapshot, selectedSpan.Start, selectedSpan.Length), isReversed);
        }
 
        view.Caret.MoveTo(new SnapshotPoint(view.TextSnapshot, testDocument.CursorPosition.Value));
 
        execute(
            workspace,
            view,
            workspace.GetService<IEditorOperationsFactoryService>());
        MarkupTestFile.GetPosition(expectedMarkup, out var expectedCode, out int _);
 
        var actual = view.TextSnapshot.GetText();
        AssertEx.Equal(expectedCode, actual);
 
        var endCaretPosition = view.Caret.Position.BufferPosition.Position;
        var actualWithCaret = actual.Insert(endCaretPosition, "$$");
 
        Assert.Equal(expectedMarkup, actualWithCaret);
    }
}