@using Microsoft.AspNetCore.Authentication

<div class="loginform">
    @if (this.User == null || this.User.Identity == null || !this.User.Identity.IsAuthenticated)
    {
        <form method="post" action="Auth/Login">
            <div>
                <label for="username">Username:</label>
            </div>
            <div>
                <input name="username" type="text" />
            </div>
            <div>
                <label for="password">Password:</label>
            </div>
            <div>
                <input name="password" type="password" />
            </div>
            <div>
                <input name="submit" type="submit" value="Login" />
            </div>
        </form>
    }
    else
    {
        var userName = User.Identity.Name;
        var dci = DataContext.Instance;
        var selectedUsers = dci.Users.Where(u => u.LdapUserName == userName);
        var userId = selectedUsers.SingleOrDefault()?.UserId;
        dci.Dispose();

        <form method="post" action="Auth/Logout">
            <div>
                Welcome, <a href="/User/@userId">@User.Identity.Name</a>!
            </div>
            <div>
                <input name="submit" type="submit" value="Logout" />
            </div>
        </form>
    }

</div>