using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.FileProviders;
using System;
using System.IO;

namespace NetCoreTestMVC2
{
    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<CookiePolicyOptions>(options =>
            {
                // This lambda determines whether user consent for non-essential cookies is needed for a given request.
                options.CheckConsentNeeded = context => true;
                options.MinimumSameSitePolicy = SameSiteMode.None;
            });

            string connectionString = Configuration["ConnectionStrings:DefaultConnection"];

            services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
            services.AddDbContext<DataContext>(options =>
            {
                options.UseSqlServer(connectionString);
            });

            //private readonly SignInManager<IdentityUser> _signInManager;
            //private readonly UserManager<IdentityUser> _userManager;

            services.AddScoped<IRepository<Student>, StudentService>();

            #region 用户系统
            //注册用户数据库，前面指定过一个DbContext了，这里add-migration的时候要指定DbContext
            //add-migration add-user-dbcontext -Context IdentityDbContext
            //合并Assembly
            //update-database -Context IdentityDbContext
            services.AddDbContext<IdentityDbContext>(options =>
            {
                options.UseSqlServer(connectionString, b => b.MigrationsAssembly("NetCoreTestMVC2"));
            });

            //注册用户服务
            services.AddDefaultIdentity<IdentityUser>().AddEntityFrameworkStores<IdentityDbContext>();

            //配置用户名、密码规则
            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 = 6;
                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;
            });
            #endregion

        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
            }

            app.UseStaticFiles();
            app.UseStaticFiles(new StaticFileOptions
            {
                RequestPath = "/node_modules",
                FileProvider = new PhysicalFileProvider(Path.Combine(env.ContentRootPath, "node_modules"))
            });
            app.UseCookiePolicy();

            //使用身份验证
            app.UseAuthentication();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });
        }
    }
}

using System.Threading.Tasks;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using NetCoreTestMVC2.Models;

namespace NetCoreTestMVC2.Controllers
{
    public class AccountController : Controller
    {
        private readonly SignInManager<IdentityUser> _signInManager;
        private readonly UserManager<IdentityUser> _userManager;

        public AccountController(SignInManager<IdentityUser> signInManager, UserManager<IdentityUser> userManager)
        {
            _signInManager = signInManager;
            _userManager = userManager;
        }

        public IActionResult Login() { return View(); }
        [HttpPost]
        public async Task<IActionResult> Login(LoginInputDto dto)
        {
            if (!ModelState.IsValid)
            {
                return View(dto);
            }
            var user = await _userManager.FindByNameAsync(dto.UserName);
            if (user != null)
            {
                var result = await _signInManager.PasswordSignInAsync(user, dto.Password, false, false);
                if (result.Succeeded)
                {
                    return RedirectToAction("Index", "Home");
                }
            }
            ModelState.AddModelError("", "用户名、密码不正确");
            return View(dto);
        }

        public IActionResult Register() { return View(); }
        [HttpPost]
        public async Task<IActionResult> Register(RegisterInputDto dto)
        {
            if (!ModelState.IsValid)
            {
                return View(dto);
            }
            var user = await _userManager.FindByNameAsync(dto.UserName);
            if (user != null)
            {
                ModelState.AddModelError("", "用户名已存在");
                return View(dto);
            }
            else
            {
                user = new IdentityUser
                {
                    UserName = dto.UserName
                };
                var result = await _userManager.CreateAsync(user, dto.Password);
                if (result.Succeeded)
                {
                    return RedirectToAction("Index", "Home");
                }
            }
            return View(dto);
        }

        [HttpPost]
        public async Task<IActionResult> Logout()
        {
            await _signInManager.SignOutAsync();
            return RedirectToAction("Index", "Home");
        }
    }
}

@*前端注入SignInManager<IdentityUser>*@
@using Microsoft.AspNetCore.Identity
@inject SignInManager<IdentityUser> _signInManager

@*判断是否登录*@
@if (_signInManager.IsSignedIn(User))
                        {
                            <li>
                                <form asp-controller="Account" asp-action="Logout" method="post">
                                    <button class="nav-link text-dark" type="submit">Logout</button>
                                </form>
                            </li>
                        }
                        else
                        {
                            <li class="nav-item">
                                <a class="nav-link text-dark" asp-area="" asp-controller="Account" asp-action="Register">Register</a>
                            </li>
                            <li class="nav-item">
                                <a class="nav-link text-dark" asp-area="" asp-controller="Account" asp-action="Login">Login</a>
                            </li>
                        }