// 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.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CodeActions;
using Microsoft.CodeAnalysis.CodeFixes;
using Microsoft.CodeAnalysis.CSharp.CodeFixes.GenerateType;
using Microsoft.CodeAnalysis.Test.Utilities;
using Roslyn.Test.Utilities;
using Xunit;
 
namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.GenerateVariable;
 
public sealed partial class GenerateVariableTests
{
    private async Task TestGeneratingTypeInRazorSourceGeneratedDocumentAsync(
        string workspaceMarkup,
        string generatedCode,
        string expectedGeneratedCode,
        bool requestFromSourceGeneratedDocument)
    {
        using var workspace = CreateWorkspaceFromOptions(workspaceMarkup, WithRazorGeneratedDocument(generatedCode));
 
        var project = workspace.CurrentSolution.Projects.Single();
        var sourceGeneratedDocument = Assert.Single(await project.GetSourceGeneratedDocumentsAsync(CancellationToken.None));
        Assert.Contains("Microsoft.NET.Sdk.Razor.SourceGenerators.RazorSourceGenerator", sourceGeneratedDocument.FilePath);
        Assert.StartsWith(
            "// <auto-generated />",
            (await sourceGeneratedDocument.GetTextAsync(CancellationToken.None)).ToString());
 
        var requestDocument = requestFromSourceGeneratedDocument
            ? sourceGeneratedDocument
            : project.Documents.Single();
 
        var requestTree = await requestDocument.GetSyntaxTreeAsync(CancellationToken.None);
        var compilation = await project.GetCompilationAsync(CancellationToken.None);
        Assert.NotNull(requestTree);
        Assert.NotNull(compilation);
 
        var diagnostic = Assert.Single(
            compilation!.GetDiagnostics(CancellationToken.None).Where(
                diagnostic => diagnostic.Severity == DiagnosticSeverity.Error && diagnostic.Location.SourceTree == requestTree));
 
        var codeActions = new List<CodeAction>();
        var context = new CodeFixContext(
            requestDocument,
            diagnostic.Location.SourceSpan,
            [diagnostic],
            (action, _) => codeActions.Add(action),
            CancellationToken.None);
 
        var provider = new GenerateTypeCodeFixProvider();
        await provider.RegisterCodeFixesAsync(context);
 
        var flattenedActions = FlattenActions([.. codeActions]);
        var codeAction = Assert.Single(
            flattenedActions.Where(action => action.Title == string.Format(FeaturesResources.Generate_nested_0_1, "class", "MissingType")));
 
        var operations = await codeAction.GetOperationsAsync(CancellationToken.None);
        var changedSolutions = await ApplyOperationsAndGetSolutionAsync(workspace, operations);
        var newSourceGeneratedDocument = await changedSolutions.Item2.GetSourceGeneratedDocumentAsync(sourceGeneratedDocument.Id, CancellationToken.None);
 
        Assert.NotNull(newSourceGeneratedDocument);
        AssertEx.EqualOrDiff(
            expectedGeneratedCode,
            (await newSourceGeneratedDocument!.GetTextAsync(CancellationToken.None)).ToString());
    }
 
    [Fact]
    public Task TestGeneratingTypeIntoRazorSourceGeneratedDocumentFromRegularDocument()
        => TestGeneratingTypeInRazorSourceGeneratedDocumentAsync(
            """
            <Workspace>
                <Project Language="C#" AssemblyName="ClassLibrary1" CommonReferences="true">
                    <Document>
            public class C
            {
                public object M()
                {
                    Component.Miss$$ingType value = null;
                    return value;
                }
            }
                    </Document>
                </Project>
            </Workspace>
            """,
            """
            // <auto-generated />
 
            using System;
 
            public partial class Component
            {
            }
            """,
            """
            // <auto-generated />
 
            using System;
 
            public partial class Component
            {
                internal class MissingType
                {
                }
            }
            """,
            requestFromSourceGeneratedDocument: false);
 
    [Fact]
    public Task TestGeneratingTypeInRazorSourceGeneratedDocument()
        => TestGeneratingTypeInRazorSourceGeneratedDocumentAsync(
            """
            <Workspace>
                <Project Language="C#" AssemblyName="ClassLibrary1" CommonReferences="true">
                    <Document>
            public class Placeholder
            {
            }
                    </Document>
                </Project>
            </Workspace>
            """,
            """
            // <auto-generated />
 
            using System;
 
            public partial class Component
            {
                public object M()
                {
                    return new MissingType();
                }
            }
            """,
            """
            // <auto-generated />
 
            using System;
 
            public partial class Component
            {
                public object M()
                {
                    return new MissingType();
                }
 
                private class MissingType
                {
                    public MissingType()
                    {
                    }
                }
            }
            """,
            requestFromSourceGeneratedDocument: true);
 
    [Fact]
    public Task TestGeneratingTypeIntoHiddenRazorSourceGeneratedDocumentFromRegularDocument()
        => TestGeneratingTypeInRazorSourceGeneratedDocumentAsync(
            """
            <Workspace>
                <Project Language="C#" AssemblyName="ClassLibrary1" CommonReferences="true">
                    <Document>
            public class C
            {
                public object M()
                {
                    Component.Miss$$ingType value = null;
                    return value;
                }
            }
                    </Document>
                </Project>
            </Workspace>
            """,
            """
            // <auto-generated />
 
            using System;
 
            #line hidden
            public partial class Component
            {
            }
            #line default
            """,
            """
            // <auto-generated />
 
            using System;
 
            #line hidden
            public partial class Component
            {
                internal class MissingType
                {
                }
            }
            #line default
            """,
            requestFromSourceGeneratedDocument: false);
 
    [Fact]
    public Task TestGeneratingTypeInHiddenRazorSourceGeneratedDocument()
        => TestGeneratingTypeInRazorSourceGeneratedDocumentAsync(
            """
            <Workspace>
                <Project Language="C#" AssemblyName="ClassLibrary1" CommonReferences="true">
                    <Document>
            public class Placeholder
            {
            }
                    </Document>
                </Project>
            </Workspace>
            """,
            """
            // <auto-generated />
 
            using System;
 
            #line hidden
            public partial class Component
            {
                public object M()
                {
                    return new MissingType();
                }
            }
            #line default
            """,
            """
            // <auto-generated />
 
            using System;
 
            #line hidden
            public partial class Component
            {
                public object M()
                {
                    return new MissingType();
                }
 
                private class MissingType
                {
                    public MissingType()
                    {
                    }
                }
            }
            #line default
            """,
            requestFromSourceGeneratedDocument: true);
}