using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;

using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Authorization;
using Microsoft.EntityFrameworkCore;

using StackExchange.Redis;

using Selector.Model;
using Selector.Model.Authorisation;
using Selector.Cache;

namespace Selector.Web
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.Configure<RootOptions>(options =>
            {
                OptionsHelper.ConfigureOptions(options, Configuration);
            });
            var config = OptionsHelper.ConfigureOptions(Configuration);

            services.AddRazorPages().AddRazorRuntimeCompilation();
            services.AddControllers();

            services.AddDbContext<ApplicationDbContext>(options => 
                options.UseNpgsql(Configuration.GetConnectionString("Default"))
            );

            services.AddIdentity<ApplicationUser, IdentityRole>()
                .AddEntityFrameworkStores<ApplicationDbContext>()
                .AddDefaultUI()
                .AddDefaultTokenProviders();

            services.Configure<IdentityOptions>(options =>
            {
                // Password settings.
                options.Password.RequireDigit = false;
                options.Password.RequireLowercase = false;
                options.Password.RequireNonAlphanumeric = false;
                options.Password.RequireUppercase = false;
                options.Password.RequiredLength = 3;
                options.Password.RequiredUniqueChars = 1;

                // Lockout settings.
                options.Lockout.DefaultLockoutTimeSpan = TimeSpan.FromMinutes(5);
                options.Lockout.MaxFailedAccessAttempts = 5;
                options.Lockout.AllowedForNewUsers = true;

                // User settings.
                options.User.AllowedUserNameCharacters =
                "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-._@+";
                options.User.RequireUniqueEmail = false;
                options.SignIn.RequireConfirmedEmail = false;
            });

            services.ConfigureApplicationCookie(options =>
            {
                // Cookie settings
                options.Cookie.HttpOnly = true;
                options.ExpireTimeSpan = TimeSpan.FromMinutes(5);

                options.LoginPath = "/Identity/Account/Login";
                options.AccessDeniedPath = "/Identity/Account/AccessDenied";
                options.SlidingExpiration = true;
            });

            services.AddAuthorization(options =>
            {
                options.FallbackPolicy = new AuthorizationPolicyBuilder()
                    .RequireAuthenticatedUser()
                    .Build();
            });

            services.AddScoped<IAuthorizationHandler, WatcherIsOwnerAuthHandler>();
            services.AddSingleton<IAuthorizationHandler, WatcherIsAdminAuthHandler>();

            services.AddScoped<IAuthorizationHandler, UserIsSelfAuthHandler>();
            services.AddSingleton<IAuthorizationHandler, UserIsAdminAuthHandler>();

            if (config.RedisOptions.Enabled)
            {
                Console.WriteLine("> Configuring Redis...");

                if (string.IsNullOrWhiteSpace(config.RedisOptions.ConnectionString))
                {
                    Console.WriteLine("> No Redis configuration string provided, exiting...");
                    Environment.Exit(1);
                }

                var connMulti = ConnectionMultiplexer.Connect(config.RedisOptions.ConnectionString);
                services.AddSingleton(connMulti);
                services.AddTransient<IDatabaseAsync>(services => services.GetService<ConnectionMultiplexer>().GetDatabase());
                services.AddTransient<ISubscriber>(services => services.GetService<ConnectionMultiplexer>().GetSubscriber());
            }
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseStaticFiles();

            app.UseRouting();

            app.UseAuthentication();
            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapRazorPages();
                endpoints.MapControllers();
            });
        }
    }
}