// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.Linq;
using System.Reflection;
using Microsoft.AspNetCore.Razor.Language;
using Microsoft.CodeAnalysis.Razor.ProjectSystem;
using Microsoft.VisualStudio.Editor.Razor;
using Xunit;

using Mvc1_X = Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X;
using MvcLatest = Microsoft.AspNetCore.Mvc.Razor.Extensions;

namespace Microsoft.CodeAnalysis.Razor
{
    // Testing this here because we need references to the MVC factories.
    public class DefaultProjectSnapshotProjectEngineFactoryTest
    {
        public DefaultProjectSnapshotProjectEngineFactoryTest()
        {
            Project project = null;

            Workspace = TestWorkspace.Create(workspace =>
            {
                var info = ProjectInfo.Create(ProjectId.CreateNewId("Test"), VersionStamp.Default, "Test", "Test", LanguageNames.CSharp, filePath: "/TestPath/SomePath/Test.csproj");
                project = workspace.CurrentSolution.AddProject(info).GetProject(info.Id);
            });

            WorkspaceProject = project;

            HostProject_For_1_0 = new HostProject("/TestPath/SomePath/Test.csproj", FallbackRazorConfiguration.MVC_1_0);
            HostProject_For_1_1 = new HostProject("/TestPath/SomePath/Test.csproj", FallbackRazorConfiguration.MVC_1_1);
            HostProject_For_2_0 = new HostProject("/TestPath/SomePath/Test.csproj", FallbackRazorConfiguration.MVC_2_0);

            HostProject_For_2_1 = new HostProject(
                "/TestPath/SomePath/Test.csproj",
                new ProjectSystemRazorConfiguration(RazorLanguageVersion.Version_2_1, "MVC-2.1", Array.Empty<RazorExtension>()));
            HostProject_For_UnknownConfiguration = new HostProject(
                "/TestPath/SomePath/Test.csproj",
                new ProjectSystemRazorConfiguration(RazorLanguageVersion.Version_2_1, "Blazor-0.1", Array.Empty<RazorExtension>()));

            Snapshot_For_1_0 = new DefaultProjectSnapshot(ProjectState.Create(Workspace.Services, HostProject_For_1_0, WorkspaceProject));
            Snapshot_For_1_1 = new DefaultProjectSnapshot(ProjectState.Create(Workspace.Services, HostProject_For_1_1, WorkspaceProject));
            Snapshot_For_2_0 = new DefaultProjectSnapshot(ProjectState.Create(Workspace.Services, HostProject_For_2_0, WorkspaceProject));
            Snapshot_For_2_1 = new DefaultProjectSnapshot(ProjectState.Create(Workspace.Services, HostProject_For_2_1, WorkspaceProject));
            Snapshot_For_UnknownConfiguration = new DefaultProjectSnapshot(ProjectState.Create(Workspace.Services, HostProject_For_UnknownConfiguration, WorkspaceProject));

            CustomFactories = new Lazy<IProjectEngineFactory, ICustomProjectEngineFactoryMetadata>[]
            {
                new Lazy<IProjectEngineFactory, ICustomProjectEngineFactoryMetadata>(
                    () => new LegacyProjectEngineFactory_1_0(),
                    typeof(LegacyProjectEngineFactory_1_0).GetCustomAttribute<ExportCustomProjectEngineFactoryAttribute>()),
                new Lazy<IProjectEngineFactory, ICustomProjectEngineFactoryMetadata>(
                    () => new LegacyProjectEngineFactory_1_1(),
                    typeof(LegacyProjectEngineFactory_1_1).GetCustomAttribute<ExportCustomProjectEngineFactoryAttribute>()),
                new Lazy<IProjectEngineFactory, ICustomProjectEngineFactoryMetadata>(
                    () => new LegacyProjectEngineFactory_2_0(),
                    typeof(LegacyProjectEngineFactory_2_0).GetCustomAttribute<ExportCustomProjectEngineFactoryAttribute>()),
                new Lazy<IProjectEngineFactory, ICustomProjectEngineFactoryMetadata>(
                    () => new LegacyProjectEngineFactory_2_1(),
                    typeof(LegacyProjectEngineFactory_2_1).GetCustomAttribute<ExportCustomProjectEngineFactoryAttribute>()),
            };

            FallbackFactory = new FallbackProjectEngineFactory();
        }

        private Lazy<IProjectEngineFactory, ICustomProjectEngineFactoryMetadata>[] CustomFactories { get; }

        private IFallbackProjectEngineFactory FallbackFactory { get; }

        private HostProject HostProject_For_1_0 { get; }

        private HostProject HostProject_For_1_1 { get; }

        private HostProject HostProject_For_2_0 { get; }

        private HostProject HostProject_For_2_1 { get; }

        private HostProject HostProject_For_UnknownConfiguration { get; }

        private ProjectSnapshot Snapshot_For_1_0 { get; }

        private ProjectSnapshot Snapshot_For_1_1 { get; }

        private ProjectSnapshot Snapshot_For_2_0 { get; }

        private ProjectSnapshot Snapshot_For_2_1 { get; }

        private ProjectSnapshot Snapshot_For_UnknownConfiguration { get; }
        
        private Project WorkspaceProject { get; }

        private Workspace Workspace { get; }

        [Fact]
        public void Create_CreatesDesignTimeTemplateEngine_ForVersion2_1()
        {
            // Arrange
            var snapshot = Snapshot_For_2_1;

            var factory = new DefaultProjectSnapshotProjectEngineFactory(FallbackFactory, CustomFactories);

            // Act
            var engine = factory.Create(snapshot, b =>
            {
                b.Features.Add(new MyCoolNewFeature());
            });

            // Assert
            Assert.Single(engine.Engine.Features.OfType<MyCoolNewFeature>());
            Assert.Single(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperDescriptorProvider>());
            Assert.Single(engine.Engine.Features.OfType<MvcLatest.MvcViewDocumentClassifierPass>());
            Assert.Single(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperPass>());
        }

        [Fact]
        public void Create_CreatesDesignTimeTemplateEngine_ForVersion2_0()
        {
            // Arrange
            var snapshot = Snapshot_For_2_0;

            var factory = new DefaultProjectSnapshotProjectEngineFactory(FallbackFactory, CustomFactories);

            // Act
            var engine = factory.Create(snapshot, b =>
            {
                b.Features.Add(new MyCoolNewFeature());
            });

            // Assert
            Assert.Single(engine.Engine.Features.OfType<MyCoolNewFeature>());
            Assert.Single(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperDescriptorProvider>());
            Assert.Single(engine.Engine.Features.OfType<MvcLatest.MvcViewDocumentClassifierPass>());
            Assert.Single(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperPass>());
        }

        [Fact]
        public void Create_CreatesTemplateEngine_ForVersion1_1()
        {
            // Arrange
            var snapshot = Snapshot_For_1_1;

            var factory = new DefaultProjectSnapshotProjectEngineFactory(FallbackFactory, CustomFactories);

            // Act
            var engine = factory.Create(snapshot, b =>
            {
                b.Features.Add(new MyCoolNewFeature());
            });

            // Assert
            Assert.Single(engine.Engine.Features.OfType<MyCoolNewFeature>());
            Assert.Single(engine.Engine.Features.OfType<Mvc1_X.ViewComponentTagHelperDescriptorProvider>());
            Assert.Single(engine.Engine.Features.OfType<Mvc1_X.MvcViewDocumentClassifierPass>());
            Assert.Single(engine.Engine.Features.OfType<Mvc1_X.ViewComponentTagHelperPass>());
        }

        [Fact]
        public void Create_DoesNotSupportViewComponentTagHelpers_ForVersion1_0()
        {
            // Arrange
            var snapshot = Snapshot_For_1_0;

            var factory = new DefaultProjectSnapshotProjectEngineFactory(FallbackFactory, CustomFactories);

            // Act
            var engine = factory.Create(snapshot, b =>
            {
                b.Features.Add(new MyCoolNewFeature());
            });

            // Assert
            Assert.Single(engine.Engine.Features.OfType<MyCoolNewFeature>());
            Assert.Empty(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperDescriptorProvider>());
            Assert.Empty(engine.Engine.Features.OfType<MvcLatest.MvcViewDocumentClassifierPass>());
            Assert.Empty(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperPass>());
        }

        [Fact]
        public void Create_ForUnknownConfiguration_UsesFallbackFactory()
        {
            var snapshot = Snapshot_For_UnknownConfiguration;

            var factory = new DefaultProjectSnapshotProjectEngineFactory(FallbackFactory, CustomFactories);

            // Act
            var engine = factory.Create(snapshot, b =>
            {
                b.Features.Add(new MyCoolNewFeature());
            });

            // Assert
            Assert.Single(engine.Engine.Features.OfType<MyCoolNewFeature>());
            Assert.Empty(engine.Engine.Features.OfType<DefaultTagHelperDescriptorProvider>());
            Assert.Empty(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperDescriptorProvider>());
            Assert.Empty(engine.Engine.Features.OfType<MvcLatest.MvcViewDocumentClassifierPass>());
            Assert.Empty(engine.Engine.Features.OfType<MvcLatest.ViewComponentTagHelperPass>());
        }

        private class MyCoolNewFeature : IRazorEngineFeature
        {
            public RazorEngine Engine { get; set; }
        }
    }
}