Add authentication

Website/Controllers/AccountController.cs

@@ -0,0 +1,54 @@
+using System;
+using System.Security.Claims;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Authentication;
+using Microsoft.AspNetCore.Authentication.Cookies;
+using Microsoft.AspNetCore.Mvc;
+using Website.Data;
+using Website.Models;
+using Website.ViewModels;
+
+namespace Website.Controllers {
+	public class AccountController:Controller {
+		private readonly UserRepository _repo;
+
+		public AccountController(UserRepository repo) => _repo = repo;
+
+		public IActionResult Index() => View();
+
+		[HttpGet]
+		public IActionResult Login(string returnUrl, bool failedAttempt = false) {
+			var model = new LoginViewModel {
+				ReturnUrl = returnUrl,
+				FailedAttempt = failedAttempt
+			};
+			return View(model);
+		}
+
+		[HttpPost]
+		public async Task<IActionResult> Login(LoginRequest request) {
+			try {
+				var user = await _repo.GetUserByEmail(request.Username);
+				return user.ValidatePassword(request.Password)
+					? await SetIdentityAndRedirect(request.ReturnUrl, user)
+					: Login(request.ReturnUrl, true);
+			}
+			catch (Exception e) {
+				return Login(request.ReturnUrl, true);
+			}
+		}
+
+		private async Task<IActionResult> SetIdentityAndRedirect(string returnUrl, User user) {
+			var identity = new ClaimsIdentity(CookieAuthenticationDefaults.AuthenticationScheme);
+			identity.AddClaim(new Claim(ClaimTypes.Name, user.Username));
+			identity.AddClaim(new Claim(ClaimTypes.Email, user.Username));
+
+			var principal = new ClaimsPrincipal(identity);
+			await HttpContext.SignInAsync(CookieAuthenticationDefaults.AuthenticationScheme, principal);
+
+			return string.IsNullOrEmpty(returnUrl)
+				? (IActionResult) RedirectToAction(nameof(Index))
+				: Redirect(returnUrl);
+		}
+	}
+}