using Autofac;
using Autofac.Extensions.DependencyInjection;
using Microsoft.ApplicationInsights.Extensibility;
using Microsoft.ApplicationInsights.ServiceFabric;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Azure.ServiceBus;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBus;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBus.Abstractions;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBusRabbitMQ;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBusServiceBus;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure.Filters;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure.Middlewares;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure.Repositories;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure.Services;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.HealthChecks;
using Microsoft.Extensions.Logging;
using RabbitMQ.Client;
using Swashbuckle.AspNetCore.Swagger;
using System;
using System.Collections.Generic;
using System.IdentityModel.Tokens.Jwt;
using System.Threading.Tasks;

namespace Microsoft.eShopOnContainers.Services.Locations.API
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        public IServiceProvider ConfigureServices(IServiceCollection services)
        {
            RegisterAppInsights(services);

            services.AddMvc(options =>
            {
                options.Filters.Add(typeof(HttpGlobalExceptionFilter));
            }).AddControllersAsServices();

            ConfigureAuthService(services);

            services.Configure<LocationSettings>(Configuration);

            if (Configuration.GetValue<bool>("AzureServiceBusEnabled"))
            {
                services.AddSingleton<IServiceBusPersisterConnection>(sp =>
                {
                    var logger = sp.GetRequiredService<ILogger<DefaultServiceBusPersisterConnection>>();

                    var serviceBusConnectionString = Configuration["EventBusConnection"];
                    var serviceBusConnection = new ServiceBusConnectionStringBuilder(serviceBusConnectionString);

                    return new DefaultServiceBusPersisterConnection(serviceBusConnection, logger);
                });
            }
            else
            {
                services.AddSingleton<IRabbitMQPersistentConnection>(sp =>
                {
                    var logger = sp.GetRequiredService<ILogger<DefaultRabbitMQPersistentConnection>>();

                    var factory = new ConnectionFactory()
                    {
                        HostName = Configuration["EventBusConnection"]
                    };

                    if (!string.IsNullOrEmpty(Configuration["EventBusUserName"]))
                    {
                        factory.UserName = Configuration["EventBusUserName"];
                    }

                    if (!string.IsNullOrEmpty(Configuration["EventBusPassword"]))
                    {
                        factory.Password = Configuration["EventBusPassword"];
                    }

                    var retryCount = 5;
                    if (!string.IsNullOrEmpty(Configuration["EventBusRetryCount"]))
                    {
                        retryCount = int.Parse(Configuration["EventBusRetryCount"]);
                    }

                    return new DefaultRabbitMQPersistentConnection(factory, logger, retryCount);
                });
            }

            services.AddHealthChecks(checks =>
            {
                checks.AddValueTaskCheck("HTTP Endpoint", () => new ValueTask<IHealthCheckResult>(HealthCheckResult.Healthy("Ok")));
            });

            RegisterEventBus(services);

            // Add framework services.
            services.AddSwaggerGen(options =>
            {
                options.DescribeAllEnumsAsStrings();
                options.SwaggerDoc("v1", new Swashbuckle.AspNetCore.Swagger.Info
                {
                    Title = "eShopOnContainers - Location HTTP API",
                    Version = "v1",
                    Description = "The Location Microservice HTTP API. This is a Data-Driven/CRUD microservice sample",
                    TermsOfService = "Terms Of Service"
                });

                options.AddSecurityDefinition("oauth2", new OAuth2Scheme
                {
                    Type = "oauth2",
                    Flow = "implicit",
                    AuthorizationUrl = $"{Configuration.GetValue<string>("IdentityUrlExternal")}/connect/authorize",
                    TokenUrl = $"{Configuration.GetValue<string>("IdentityUrlExternal")}/connect/token",
                    Scopes = new Dictionary<string, string>()
                    {
                        { "locations", "Locations API" }
                    }
                });

                options.OperationFilter<AuthorizeCheckOperationFilter>();

            });

            services.AddCors(options =>
            {
                options.AddPolicy("CorsPolicy",
                    builder => builder.AllowAnyOrigin()
                    .AllowAnyMethod()
                    .AllowAnyHeader()
                    .AllowCredentials());
            });

            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
            services.AddTransient<IIdentityService, IdentityService>();
            services.AddTransient<ILocationsService, LocationsService>();
            services.AddTransient<ILocationsRepository, LocationsRepository>();

            //configure autofac
            var container = new ContainerBuilder();
            container.Populate(services);

            return new AutofacServiceProvider(container.Build());
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddAzureWebAppDiagnostics();
            loggerFactory.AddApplicationInsights(app.ApplicationServices, LogLevel.Trace);

            var pathBase = Configuration["PATH_BASE"];
            if (!string.IsNullOrEmpty(pathBase))
            {
                app.UsePathBase(pathBase);
            }

#pragma warning disable CS1998 // Async method lacks 'await' operators and will run synchronously
            app.Map("/liveness", lapp => lapp.Run(async ctx => ctx.Response.StatusCode = 200));
#pragma warning restore CS1998 // Async method lacks 'await' operators and will run synchronously

            app.UseCors("CorsPolicy");

            ConfigureAuth(app);

            app.UseMvcWithDefaultRoute();

            app.UseSwagger()
              .UseSwaggerUI(c =>
              {
                  c.SwaggerEndpoint($"{ (!string.IsNullOrEmpty(pathBase) ? pathBase : string.Empty) }/swagger/v1/swagger.json", "Locations.API V1");
                  c.OAuthClientId("locationsswaggerui");
                  c.OAuthAppName("Locations Swagger UI");
              });

            LocationsContextSeed.SeedAsync(app, loggerFactory)
                .Wait();
        }

        private void RegisterAppInsights(IServiceCollection services)
        {
            services.AddApplicationInsightsTelemetry(Configuration);
            var orchestratorType = Configuration.GetValue<string>("OrchestratorType");

            if (orchestratorType?.ToUpper() == "K8S")
            {
                // Enable K8s telemetry initializer
                services.EnableKubernetes();
            }
            if (orchestratorType?.ToUpper() == "SF")
            {
                // Enable SF telemetry initializer
                services.AddSingleton<ITelemetryInitializer>((serviceProvider) =>
                    new FabricTelemetryInitializer());
            }
        }

        private void ConfigureAuthService(IServiceCollection services)
        {
            // prevent from mapping "sub" claim to nameidentifier.
            JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();

            services.AddAuthentication(options =>
            {
                options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
                options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            })
            .AddJwtBearer(options =>
            {
                options.Authority = Configuration.GetValue<string>("IdentityUrl");
                options.Audience = "locations";
                options.RequireHttpsMetadata = false;
            });
        }

        protected virtual void ConfigureAuth(IApplicationBuilder app)
        {
            if (Configuration.GetValue<bool>("UseLoadTest"))
            {
                app.UseMiddleware<ByPassAuthMiddleware>();
            }

            app.UseAuthentication();
        }

        private void RegisterEventBus(IServiceCollection services)
        {
            var subscriptionClientName = Configuration["SubscriptionClientName"];

            if (Configuration.GetValue<bool>("AzureServiceBusEnabled"))
            {
                services.AddSingleton<IEventBus, EventBusServiceBus>(sp =>
                {
                    var serviceBusPersisterConnection = sp.GetRequiredService<IServiceBusPersisterConnection>();
                    var iLifetimeScope = sp.GetRequiredService<ILifetimeScope>();
                    var logger = sp.GetRequiredService<ILogger<EventBusServiceBus>>();
                    var eventBusSubcriptionsManager = sp.GetRequiredService<IEventBusSubscriptionsManager>();

                    return new EventBusServiceBus(serviceBusPersisterConnection, logger,
                        eventBusSubcriptionsManager, subscriptionClientName, iLifetimeScope);
                });
            }
            else
            {
                services.AddSingleton<IEventBus, EventBusRabbitMQ>(sp =>
                {
                    var rabbitMQPersistentConnection = sp.GetRequiredService<IRabbitMQPersistentConnection>();
                    var iLifetimeScope = sp.GetRequiredService<ILifetimeScope>();
                    var logger = sp.GetRequiredService<ILogger<EventBusRabbitMQ>>();
                    var eventBusSubcriptionsManager = sp.GetRequiredService<IEventBusSubscriptionsManager>();

                    var retryCount = 5;
                    if (!string.IsNullOrEmpty(Configuration["EventBusRetryCount"]))
                    {
                        retryCount = int.Parse(Configuration["EventBusRetryCount"]);
                    }

                    return new EventBusRabbitMQ(rabbitMQPersistentConnection, logger, iLifetimeScope, eventBusSubcriptionsManager, subscriptionClientName, retryCount);
                });
            }

            services.AddSingleton<IEventBusSubscriptionsManager, InMemoryEventBusSubscriptionsManager>();
        }
    }
}