// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System;
using System.Linq;
using Microsoft.AspNetCore.Mvc.Abstractions;
using Microsoft.AspNetCore.Mvc.ApplicationModels;
using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.AspNetCore.Mvc.Razor;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
using Microsoft.AspNetCore.Mvc.Routing;
using Microsoft.AspNetCore.Routing;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Options;
using Resources = Microsoft.AspNetCore.Mvc.RazorPages.Resources;

namespace Microsoft.Extensions.DependencyInjection
{
    /// <summary>
    /// Static class that adds razor page functionality to <see cref="IMvcCoreBuilder"/>.
    /// </summary>
    public static class MvcRazorPagesMvcCoreBuilderExtensions
    {
        /// <summary>
        /// Register services needed for Razor Pages.
        /// </summary>
        /// <param name="builder">The <see cref="IMvcCoreBuilder"/>.</param>
        /// <returns>The <see cref="IMvcCoreBuilder"/>.</returns>
        public static IMvcCoreBuilder AddRazorPages(this IMvcCoreBuilder builder)
        {
            if (builder == null)
            {
                throw new ArgumentNullException(nameof(builder));
            }

            builder.AddRazorViewEngine();

            AddRazorPagesServices(builder.Services);

            return builder;
        }

        /// <summary>
        /// Register services needed for Razor Pages.
        /// </summary>
        /// <param name="builder">The <see cref="IMvcCoreBuilder"/>.</param>
        /// <param name="setupAction">The action to setup the <see cref="RazorPagesOptions"/>.</param>
        /// <returns>The <see cref="IMvcCoreBuilder"/>.</returns>
        public static IMvcCoreBuilder AddRazorPages(
            this IMvcCoreBuilder builder,
            Action<RazorPagesOptions> setupAction)
        {
            if (builder == null)
            {
                throw new ArgumentNullException(nameof(builder));
            }

            if (setupAction == null)
            {
                throw new ArgumentNullException(nameof(setupAction));
            }

            builder.AddRazorViewEngine();

            AddRazorPagesServices(builder.Services);

            builder.Services.Configure(setupAction);

            return builder;
        }

        /// <summary>
        /// Configures Razor Pages to use the specified <paramref name="rootDirectory"/>.
        /// </summary>
        /// <param name="builder">The <see cref="IMvcCoreBuilder"/>.</param>
        /// <param name="rootDirectory">The application relative path to use as the root directory.</param>
        /// <returns></returns>
        public static IMvcCoreBuilder WithRazorPagesRoot(this IMvcCoreBuilder builder, string rootDirectory)
        {
            if (builder == null)
            {
                throw new ArgumentNullException(nameof(builder));
            }

            if (string.IsNullOrEmpty(rootDirectory))
            {
                throw new ArgumentException(Resources.ArgumentCannotBeNullOrEmpty, nameof(rootDirectory));
            }

            builder.Services.Configure<RazorPagesOptions>(options => options.RootDirectory = rootDirectory);
            return builder;
        }

        // Internal for testing.
        internal static void AddRazorPagesServices(IServiceCollection services)
        {
            // Options
            services.TryAddEnumerable(
                ServiceDescriptor.Transient<IConfigureOptions<RazorViewEngineOptions>, RazorPagesRazorViewEngineOptionsSetup>());

            services.TryAddEnumerable(
                ServiceDescriptor.Transient<IConfigureOptions<RazorPagesOptions>, RazorPagesOptionsSetup>());

            // Routing
            services.TryAddEnumerable(ServiceDescriptor.Singleton<MatcherPolicy, DynamicPageEndpointMatcherPolicy>());
            services.TryAddSingleton<DynamicPageEndpointSelectorCache>();
            services.TryAddSingleton<PageActionEndpointDataSourceIdProvider>();

            // Action description and invocation
            var actionDescriptorProvider = services.FirstOrDefault(f =>
                f.ServiceType == typeof(IActionDescriptorProvider) &&
                f.ImplementationType == typeof(PageActionDescriptorProvider));

            if (actionDescriptorProvider is null)
            {
                // RuntimeCompilation registers an instance of PageActionDescriptorProvider (PageADP). CompiledPageADP and runtime compilation
                // cannot co-exist since CompiledPageADP will attempt to resolve action descriptors for lazily compiled views (such as for
                // ones from non-physical file providers). We'll instead avoid adding it if PageADP is already registered. Similarly,
                // AddRazorRuntimeCompilation will remove CompiledPageADP if it is registered.
                services.TryAddEnumerable(
                    ServiceDescriptor.Singleton<IActionDescriptorProvider, CompiledPageActionDescriptorProvider>());
            }
            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IPageRouteModelProvider, CompiledPageRouteModelProvider>());
            services.TryAddSingleton<PageActionEndpointDataSourceFactory>();
            services.TryAddEnumerable(ServiceDescriptor.Singleton<MatcherPolicy, DynamicPageEndpointMatcherPolicy>());

            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IPageApplicationModelProvider, DefaultPageApplicationModelProvider>());
            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IPageApplicationModelProvider, AutoValidateAntiforgeryPageApplicationModelProvider>());
            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IPageApplicationModelProvider, AuthorizationPageApplicationModelProvider>());
            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IPageApplicationModelProvider, TempDataFilterPageApplicationModelProvider>());
            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IPageApplicationModelProvider, ViewDataAttributePageApplicationModelProvider>());
            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IPageApplicationModelProvider, ResponseCacheFilterApplicationModelProvider>());

            services.TryAddSingleton<IPageApplicationModelPartsProvider, DefaultPageApplicationModelPartsProvider>();

            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IActionInvokerProvider, PageActionInvokerProvider>());
            services.TryAddEnumerable(
                ServiceDescriptor.Singleton<IRequestDelegateFactory, PageRequestDelegateFactory>());
            services.TryAddSingleton<PageActionInvokerCache>();

            // Page and Page model creation and activation
            services.TryAddSingleton<IPageModelActivatorProvider, DefaultPageModelActivatorProvider>();
            services.TryAddSingleton<IPageModelFactoryProvider, DefaultPageModelFactoryProvider>();

            services.TryAddSingleton<IPageActivatorProvider, DefaultPageActivatorProvider>();
            services.TryAddSingleton<IPageFactoryProvider, DefaultPageFactoryProvider>();

#pragma warning disable CS0618 // Type or member is obsolete
            services.TryAddSingleton<IPageLoader>(s => s.GetRequiredService<PageLoader>());
#pragma warning restore CS0618 // Type or member is obsolete
            services.TryAddSingleton<PageLoader, DefaultPageLoader>();
            services.TryAddSingleton<IPageHandlerMethodSelector, DefaultPageHandlerMethodSelector>();

            // Action executors
            services.TryAddSingleton<PageResultExecutor>();

            services.TryAddTransient<PageSaveTempDataPropertyFilter>();
        }
    }
}
