secure-sharing/SecureSharing/Areas/Identity/Pages/Account/Login.cshtml.cs

using System.ComponentModel.DataAnnotations;
using Microsoft.AspNetCore.Authentication;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;

namespace SecureSharing.Areas.Identity.Pages.Account;

[AllowAnonymous]
public sealed class LoginModel : PageModel
{
    private readonly ILogger<LoginModel> _logger;
    private readonly SignInManager<IdentityUser> _signInManager;
    private readonly UserManager<IdentityUser> _userManager;

    public LoginModel(SignInManager<IdentityUser> signInManager,
        ILogger<LoginModel> logger,
        UserManager<IdentityUser> userManager)
    {
        _userManager = userManager;
        _signInManager = signInManager;
        _logger = logger;
    }

    [BindProperty] public InputModel Input { get; set; }

    public IList<AuthenticationScheme> ExternalLogins { get; set; }

    public string ReturnUrl { get; set; }

    [TempData] public string ErrorMessage { get; set; }

    public async Task OnGetAsync(string returnUrl = null)
    {
        if (!string.IsNullOrEmpty(ErrorMessage)) ModelState.AddModelError(string.Empty, ErrorMessage);

        returnUrl ??= Url.Content("~/");

        // Clear the existing external cookie to ensure a clean login process
        await HttpContext.SignOutAsync(IdentityConstants.ExternalScheme);

        ExternalLogins = (await _signInManager.GetExternalAuthenticationSchemesAsync()).ToList();

        ReturnUrl = returnUrl;
    }

    public async Task<IActionResult> OnPostAsync(string returnUrl = null)
    {
        returnUrl ??= Url.Content("~/");

        ExternalLogins = (await _signInManager.GetExternalAuthenticationSchemesAsync()).ToList();

        if (ModelState.IsValid)
        {
            // This doesn't count login failures towards account lockout
            // To enable password failures to trigger account lockout, set lockoutOnFailure: true
            var result = await _signInManager.PasswordSignInAsync(Input.Email, Input.Password, Input.RememberMe, false);
            if (result.Succeeded)
            {
                _logger.LogInformation("User logged in.");
                return LocalRedirect(returnUrl);
            }

            if (result.RequiresTwoFactor)
                return RedirectToPage("./LoginWith2fa", new { ReturnUrl = returnUrl, Input.RememberMe });
            if (result.IsLockedOut)
            {
                _logger.LogWarning("User account locked out.");
                return RedirectToPage("./Lockout");
            }

            ModelState.AddModelError(string.Empty, "Invalid login attempt.");
            return Page();
        }

        // If we got this far, something failed, redisplay form
        return Page();
    }

    public sealed class InputModel
    {
        [Required] [EmailAddress] public string Email { get; set; }

        [Required]
        [DataType(DataType.Password)]
        public string Password { get; set; }

        [Display(Name = "Remember me?")] public bool RememberMe { get; set; }
    }
}