// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;
using Identity.ExternalClaims.Data;
using Microsoft.AspNetCore.Authentication;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.Extensions.Logging;
 
namespace Identity.ExternalClaims.Pages.Account;
 
public class LoginModel : PageModel
{
    private readonly SignInManager<ApplicationUser> _signInManager;
    private readonly ILogger<LoginModel> _logger;
 
    public LoginModel(SignInManager<ApplicationUser> signInManager, ILogger<LoginModel> logger)
    {
        _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 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; }
    }
 
    public async Task OnGetAsync(string returnUrl = null)
    {
        if (!string.IsNullOrEmpty(ErrorMessage))
        {
            ModelState.AddModelError(string.Empty, ErrorMessage);
        }
 
        // 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 = returnUrl;
 
        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, lockoutOnFailure: true);
            if (result.Succeeded)
            {
                _logger.LogInformation("User logged in.");
                return LocalRedirect(Url.GetLocalUrl(returnUrl));
            }
            if (result.RequiresTwoFactor)
            {
                return RedirectToPage("./LoginWith2fa", new { ReturnUrl = returnUrl, RememberMe = Input.RememberMe });
            }
            if (result.IsLockedOut)
            {
                _logger.LogWarning("User account locked out.");
                return RedirectToPage("./Lockout");
            }
            else
            {
                ModelState.AddModelError(string.Empty, "Invalid login attempt.");
                return Page();
            }
        }
 
        // If we got this far, something failed, redisplay form
        return Page();
    }
}