hn-dotnet/Apps/Website/Controllers/AccountsController.cs

using System.Linq;
using System.Threading.Tasks;
using HN.Infrastructure;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using Website.Models;

namespace Website.Controllers
{
  public sealed class AccountsController : BaseController
  {
    private readonly UserManager<User> _userManager;
    private readonly SignInManager<User> _signInManager;

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

    [AllowAnonymous]
    public IActionResult Register()
    {
      return View();
    }

    [HttpPost]
    [ValidateAntiForgeryToken]
    [AllowAnonymous]
    public async Task<IActionResult> Register(RegisterViewModel command)
    {
      if (!ModelState.IsValid)
      {
        return View(command);
      }

      var user = new User(command.Username);
      var result = await _userManager.CreateAsync(user, command.Password);

      if (!result.Succeeded)
      {
        ModelState.AddModelError(nameof(RegisterViewModel.Username), string.Join(", ", result.Errors.Select(e => e.Description)));
        return View(command);
      }

      SetFlash("Account created, you can now sign in!");

      return RedirectToAction(nameof(Login));
    }

    [AllowAnonymous]
    public IActionResult Login()
    {
      return View();
    }

    [HttpPost]
    [ValidateAntiForgeryToken]
    [AllowAnonymous]
    public async Task<IActionResult> Login(LoginViewModel command)
    {
      if (!ModelState.IsValid)
      {
        return View();
      }

      var user = await _userManager.FindByNameAsync(command.Username);

      if (user == null)
      {
        ModelState.AddModelError(nameof(LoginViewModel.Username), "Could not verify user identity");
        return View();
      }

      var result = await _signInManager.PasswordSignInAsync(user, command.Password, true, false);

      if (!result.Succeeded)
      {
        ModelState.AddModelError(nameof(LoginViewModel.Username), "Could not verify user identity");
        return View();
      }

      SetFlash("Successfuly connected!");

      return RedirectToAction(nameof(LinksController.Index), "Links");
    }

    [HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Logout()
    {
      await _signInManager.SignOutAsync();

      SetFlash("Successfuly disconnected!");

      return RedirectToAction(nameof(Login));
    }
  }
}