CouchLog/CouchLog/Components/Account/Pages/Register.razor

@page "/Account/Register"

@using System.ComponentModel.DataAnnotations
@using System.Text
@using System.Text.Encodings.Web
@using Microsoft.AspNetCore.Identity
@using Microsoft.AspNetCore.WebUtilities
@using CouchLog.Data

@inject UserManager<ApplicationUser> UserManager
@inject IUserStore<ApplicationUser> UserStore
@inject SignInManager<ApplicationUser> SignInManager
@inject ILogger<Register> Logger
@inject NavigationManager NavigationManager
@inject IdentityRedirectManager RedirectManager
@inject ApplicationDbContext CouchLogDB

<PageTitle>Register</PageTitle>

<h1>Register</h1>

<div class="row">
    <div class="col-lg-6">
        <StatusMessage Message="@Message" />
        <EditForm Model="Input" asp-route-returnUrl="@ReturnUrl" method="post" OnValidSubmit="RegisterUser" FormName="register">
            <DataAnnotationsValidator />
            <h2>Create a new account.</h2>
            <hr />
            <ValidationSummary class="text-danger" role="alert" />
            <div class="form-floating mb-3">
                <InputText @bind-Value="Input.Username" id="Input.Username" class="form-control" autocomplete="username" aria-required="true" placeholder="NewUsername" />
                <label for="Input.Username">Username</label>
                <ValidationMessage For="() => Input.Username" class="text-danger" />
            </div>
            <div class="form-floating mb-3">
                <InputText type="password" @bind-Value="Input.Password" id="Input.Password" class="form-control" autocomplete="new-password" aria-required="true" placeholder="password" />
                <label for="Input.Password">Password</label>
                <ValidationMessage For="() => Input.Password" class="text-danger" />
            </div>
            <div class="form-floating mb-3">
                <InputText type="password" @bind-Value="Input.ConfirmPassword" id="Input.ConfirmPassword" class="form-control" autocomplete="new-password" aria-required="true" placeholder="password" />
                <label for="Input.ConfirmPassword">Confirm Password</label>
                <ValidationMessage For="() => Input.ConfirmPassword" class="text-danger" />
            </div>
            <button type="submit" class="w-100 btn btn-lg btn-primary">Register</button>
        </EditForm>
    </div>
    <div class="col-lg-4 col-lg-offset-2">
        <section>
            <h3>Use another service to register.</h3>
            <hr />
            <ExternalLoginPicker />
        </section>
    </div>
</div>

@code {
    private IEnumerable<IdentityError>? identityErrors;

    [SupplyParameterFromForm]
    private InputModel Input { get; set; } = new();

    [SupplyParameterFromQuery]
    private string? ReturnUrl { get; set; }

    private string? Message => identityErrors is null ? null : $"Error: {string.Join(", ", identityErrors.Select(error => error.Description))}";

    public async Task RegisterUser(EditContext editContext)
    {
        if(!CouchLogDB.AccountsSettings.First().IsRegistrationAllowed)
        {
            identityErrors = new[]
            {
                new IdentityError { Description = "Registration is deactivated" }
            };
            return;
        }

        var user = CreateUser();

        await UserStore.SetUserNameAsync(user, Input.Username, CancellationToken.None);
        user.EmailConfirmed = true;
        var result = await UserManager.CreateAsync(user, Input.Password);

        if (!result.Succeeded)
        {
            identityErrors = result.Errors;
            return;
        }

        if(CouchLogDB.CouchLogState.Count() == 0)
        {
            await UserManager.AddToRoleAsync(user, "Admin");
            await CouchLogDB.CouchLogState.AddAsync(new CouchLogState
            {
                Id = 1,
                InitializationDate = DateTime.Now,
                IsInitialized = true
            });
        }
        else
        {
            await UserManager.AddToRoleAsync(user, "User");
        }

        await CouchLogDB.SaveChangesAsync();

        Logger.LogInformation("User created a new account with password.");

        await SignInManager.SignInAsync(user, isPersistent: false);
        RedirectManager.RedirectTo(ReturnUrl);
    }

    private ApplicationUser CreateUser()
    {
        try
        {
            return Activator.CreateInstance<ApplicationUser>();
        }
        catch
        {
            throw new InvalidOperationException($"Can't create an instance of '{nameof(ApplicationUser)}'. " +
                $"Ensure that '{nameof(ApplicationUser)}' is not an abstract class and has a parameterless constructor.");
        }
    }

    private IUserEmailStore<ApplicationUser> GetEmailStore()
    {
        if (!UserManager.SupportsUserEmail)
        {
            throw new NotSupportedException("The default UI requires a user store with email support.");
        }
        return (IUserEmailStore<ApplicationUser>)UserStore;
    }

    private sealed class InputModel
    {
        [Required]
        [Display(Name = "Username")]
        public string Username { get; set; } = "";

        [Required]
        [StringLength(100, ErrorMessage = "The {0} must be at least {2} and at max {1} characters long.", MinimumLength = 6)]
        [DataType(DataType.Password)]
        [Display(Name = "Password")]
        public string Password { get; set; } = "";

        [DataType(DataType.Password)]
        [Display(Name = "Confirm password")]
        [Compare("Password", ErrorMessage = "The password and confirmation password do not match.")]
        public string ConfirmPassword { get; set; } = "";
    }
}