using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Linq.Expressions;
using System.Security.Claims;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Data.Entity;

namespace Microsoft.AspNet.Identity.Entity
{
    public class UserStore :
        UserStore<IdentityUser, IdentityRole, string, IdentityUserLogin, IdentityUserRole, IdentityUserClaim>
    {
        public UserStore(EntityContext context) : base(context) { }
    }

    public class UserStore<TUser, TRole, TKey, TUserLogin, TUserRole, TUserClaim> :
        IUserLoginStore<TUser>,
        IUserClaimStore<TUser>,
        IUserRoleStore<TUser>,
        IUserPasswordStore<TUser>,
        IUserSecurityStampStore<TUser>,
        IQueryableUserStore<TUser>,
        IUserEmailStore<TUser>,
        IUserPhoneNumberStore<TUser>,
        IUserTwoFactorStore<TUser>,
        IUserLockoutStore<TUser>
        where TKey : IEquatable<TKey>
        where TUser : IdentityUser<TKey, TUserLogin, TUserRole, TUserClaim>
        where TRole : IdentityRole<TKey, TUserRole>
        where TUserLogin : IdentityUserLogin<TKey>, new()
        where TUserRole : IdentityUserRole<TKey>, new()
        where TUserClaim : IdentityUserClaim<TKey>, new()
    {
        private bool _disposed;

        public UserStore(EntityContext context)
        {
            if (context == null)
            {
                throw new ArgumentNullException("context");
            }
            Context = context;
            AutoSaveChanges = true;
        }

        public EntityContext Context { get; private set; }

        /// <summary>
        ///     If true will call SaveChanges after CreateAsync/UpdateAsync/DeleteAsync
        /// </summary>
        public bool AutoSaveChanges { get; set; }

        private Task SaveChanges(CancellationToken cancellationToken)
        {
            return AutoSaveChanges ? Context.SaveChangesAsync(cancellationToken) : Task.FromResult(0);
        }

        protected virtual Task<TUser> GetUserAggregate(Expression<Func<TUser, bool>> filter, CancellationToken cancellationToken = default(CancellationToken))
        {
            return Users.SingleOrDefaultAsync(filter, cancellationToken);
                //Include(u => u.Roles)
                //.Include(u => u.Claims)
                //.Include(u => u.Logins)
        }

        public Task<string> GetUserIdAsync(TUser user, CancellationToken cancellationToken = new CancellationToken())
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(Convert.ToString(user.Id, CultureInfo.InvariantCulture));
        }

        public Task<string> GetUserNameAsync(TUser user, CancellationToken cancellationToken = new CancellationToken())
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.UserName);
        }

        public Task SetUserNameAsync(TUser user, string userName, CancellationToken cancellationToken = new CancellationToken())
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.UserName = userName;
            return Task.FromResult(0);
        }

        public async virtual Task CreateAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            await Context.AddAsync(user, cancellationToken);
            await SaveChanges(cancellationToken);
        }

        public async virtual Task UpdateAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            await Context.UpdateAsync(user, cancellationToken);
            await SaveChanges(cancellationToken);
        }

        public async virtual Task DeleteAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            Context.Delete(user);
            await SaveChanges(cancellationToken);
        }

        public virtual TKey ConvertUserId(string userId)
        {
            return (TKey)Convert.ChangeType(userId, typeof(TKey));
        }

        /// <summary>
        ///     FindByLoginAsync a user by id
        /// </summary>
        /// <param name="userId"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<TUser> FindByIdAsync(string userId, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            var id = ConvertUserId(userId);
            return Users.SingleOrDefaultAsync(u => u.Id.Equals(id), cancellationToken);
            // TODO: return GetUserAggregate(u => u.Id.Equals(userId), cancellationToken);
        }

        /// <summary>
        ///     FindByLoginAsync a user by name
        /// </summary>
        /// <param name="userName"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<TUser> FindByNameAsync(string userName, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            return Users.SingleOrDefaultAsync(u => u.UserName.ToUpper() == userName.ToUpper(), cancellationToken);
            // TODO: return GetUserAggregate(u => u.UserName.ToUpper() == userName.ToUpper(), cancellationToken);
        }

        public IQueryable<TUser> Users
        {
            get { return Context.Set<TUser>(); }
        }

        public async virtual Task AddLoginAsync(TUser user, UserLoginInfo login, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            if (login == null)
            {
                throw new ArgumentNullException("login");
            }
            var l = new TUserLogin
            {
                UserId = user.Id,
                ProviderKey = login.ProviderKey,
                LoginProvider = login.LoginProvider
            };
            await Context.Set<TUserLogin>().AddAsync(l, cancellationToken);
            user.Logins.Add(l);
        }

        public virtual Task RemoveLoginAsync(TUser user, UserLoginInfo login, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            throw new NotImplementedException();
        }

        public virtual Task<IList<UserLoginInfo>> GetLoginsAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            IList<UserLoginInfo> result =
                user.Logins.Select(l => new UserLoginInfo(l.LoginProvider, l.ProviderKey)).ToList();
            return Task.FromResult(result);
        }

        public async virtual Task<TUser> FindByLoginAsync(UserLoginInfo login, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (login == null)
            {
                throw new ArgumentNullException("login");
            }
            var provider = login.LoginProvider;
            var key = login.ProviderKey;
            // TODO: use FirstOrDefaultAsync
            var userLogin =
                Context.Set<TUserLogin>().FirstOrDefault(l => l.LoginProvider == provider && l.ProviderKey == key);
            if (userLogin != null)
            {
                return await GetUserAggregate(u => u.Id.Equals(userLogin.UserId), cancellationToken);
            }
            return null;
        }

        /// <summary>
        ///     Set the password hash for a user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="passwordHash"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetPasswordHashAsync(TUser user, string passwordHash, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.PasswordHash = passwordHash;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Get the password hash for a user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<string> GetPasswordHashAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.PasswordHash);
        }

        /// <summary>
        ///     Returns true if the user has a password set
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<bool> HasPasswordAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            return Task.FromResult(user.PasswordHash != null);
        }

        /// <summary>
        ///     Return the claims for a user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<IList<Claim>> GetClaimsAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            IList<Claim> result = user.Claims.Select(c => new Claim(c.ClaimType, c.ClaimValue)).ToList();
            return Task.FromResult(result);
        }

        /// <summary>
        ///     Add a claim to a user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="claim"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task AddClaimAsync(TUser user, Claim claim, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            if (claim == null)
            {
                throw new ArgumentNullException("claim");
            }
            user.Claims.Add(new TUserClaim { UserId = user.Id, ClaimType = claim.Type, ClaimValue = claim.Value });
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Remove a claim from a user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="claim"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task RemoveClaimAsync(TUser user, Claim claim, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            if (claim == null)
            {
                throw new ArgumentNullException("claim");
            }
            var claims =
                user.Claims.Where(uc => uc.ClaimValue == claim.Value && uc.ClaimType == claim.Type).ToList();
            foreach (var c in claims)
            {
                user.Claims.Remove(c);
            }
            // TODO:these claims might not exist in the dbset
            //var query =
            //    _userClaims.Where(
            //        uc => uc.UserId.Equals(user.Id) && uc.ClaimValue == claim.Value && uc.ClaimType == claim.Type);
            //foreach (var c in query)
            //{
            //    _userClaims.Remove(c);
            //}
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Returns whether the user email is confirmed
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<bool> GetEmailConfirmedAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.EmailConfirmed);
        }

        /// <summary>
        ///     Set IsConfirmed on the user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="confirmed"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetEmailConfirmedAsync(TUser user, bool confirmed, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.EmailConfirmed = confirmed;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Set the user email
        /// </summary>
        /// <param name="user"></param>
        /// <param name="email"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetEmailAsync(TUser user, string email, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.Email = email;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Get the user's email
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<string> GetEmailAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.Email);
        }

        /// <summary>
        ///     FindByLoginAsync a user by email
        /// </summary>
        /// <param name="email"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<TUser> FindByEmailAsync(string email, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            return Task.FromResult(Users.SingleOrDefault(u => u.Email.ToUpper() == email.ToUpper()));
            //return GetUserAggregate(u => u.Email.ToUpper() == email.ToUpper(), cancellationToken);
        }

        /// <summary>
        ///     Returns the DateTimeOffset that represents the end of a user's lockout, any time in the past should be considered
        ///     not locked out.
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<DateTimeOffset> GetLockoutEndDateAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return
                Task.FromResult(user.LockoutEndDateUtc.HasValue
                    ? new DateTimeOffset(DateTime.SpecifyKind(user.LockoutEndDateUtc.Value, DateTimeKind.Utc))
                    : new DateTimeOffset());
        }

        /// <summary>
        ///     Locks a user out until the specified end date (set to a past date, to unlock a user)
        /// </summary>
        /// <param name="user"></param>
        /// <param name="lockoutEnd"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetLockoutEndDateAsync(TUser user, DateTimeOffset lockoutEnd, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.LockoutEndDateUtc = lockoutEnd == DateTimeOffset.MinValue ? (DateTime?)null : lockoutEnd.UtcDateTime;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Used to record when an attempt to access the user has failed
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<int> IncrementAccessFailedCountAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.AccessFailedCount++;
            return Task.FromResult(user.AccessFailedCount);
        }

        /// <summary>
        ///     Used to reset the account access count, typically after the account is successfully accessed
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task ResetAccessFailedCountAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.AccessFailedCount = 0;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Returns the current number of failed access attempts.  This number usually will be reset whenever the password is
        ///     verified or the account is locked out.
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<int> GetAccessFailedCountAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.AccessFailedCount);
        }

        /// <summary>
        ///     Returns whether the user can be locked out.
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<bool> GetLockoutEnabledAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.LockoutEnabled);
        }

        /// <summary>
        ///     Sets whether the user can be locked out.
        /// </summary>
        /// <param name="user"></param>
        /// <param name="enabled"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetLockoutEnabledAsync(TUser user, bool enabled, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.LockoutEnabled = enabled;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Set the user's phone number
        /// </summary>
        /// <param name="user"></param>
        /// <param name="phoneNumber"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetPhoneNumberAsync(TUser user, string phoneNumber, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.PhoneNumber = phoneNumber;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Get a user's phone number
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<string> GetPhoneNumberAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.PhoneNumber);
        }

        /// <summary>
        ///     Returns whether the user phoneNumber is confirmed
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<bool> GetPhoneNumberConfirmedAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.PhoneNumberConfirmed);
        }

        /// <summary>
        ///     Set PhoneNumberConfirmed on the user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="confirmed"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetPhoneNumberConfirmedAsync(TUser user, bool confirmed, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.PhoneNumberConfirmed = confirmed;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Add a user to a role
        /// </summary>
        /// <param name="user"></param>
        /// <param name="roleName"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task AddToRoleAsync(TUser user, string roleName, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            // TODO:
            //if (String.IsNullOrWhiteSpace(roleName))
            //{
            //    throw new ArgumentException(IdentityResources.ValueCannotBeNullOrEmpty, "roleName");
            //}
            var roleEntity = Context.Set<TRole>().SingleOrDefault(r => r.Name.ToUpper() == roleName.ToUpper());
            if (roleEntity == null)
            {
                throw new InvalidOperationException("Role Not Found");
                //TODO: String.Format(CultureInfo.CurrentCulture, IdentityResources.RoleNotFound, roleName));
            }
            var ur = new TUserRole { UserId = user.Id, RoleId = roleEntity.Id };
            user.Roles.Add(ur);
            roleEntity.Users.Add(ur);
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Remove a user from a role
        /// </summary>
        /// <param name="user"></param>
        /// <param name="roleName"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task RemoveFromRoleAsync(TUser user, string roleName, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            //if (String.IsNullOrWhiteSpace(roleName))
            //{
            //    throw new ArgumentException(IdentityResources.ValueCannotBeNullOrEmpty, "roleName");
            //}
            throw new NotImplementedException();
        }

        /// <summary>
        ///     Get the names of the roles a user is a member of
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<IList<string>> GetRolesAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            throw new NotImplementedException();
        }

        /// <summary>
        ///     Returns true if the user is in the named role
        /// </summary>
        /// <param name="user"></param>
        /// <param name="roleName"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<bool> IsInRoleAsync(TUser user, string roleName, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            //if (String.IsNullOrWhiteSpace(roleName))
            //{
            //    throw new ArgumentException(IdentityResources.ValueCannotBeNullOrEmpty, "roleName");
            //}
            throw new NotImplementedException();
        }

        /// <summary>
        ///     Set the security stamp for the user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="stamp"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetSecurityStampAsync(TUser user, string stamp, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.SecurityStamp = stamp;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Get the security stamp for a user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<string> GetSecurityStampAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.SecurityStamp);
        }

        /// <summary>
        ///     Set whether two factor authentication is enabled for the user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="enabled"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task SetTwoFactorEnabledAsync(TUser user, bool enabled, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            user.TwoFactorEnabled = enabled;
            return Task.FromResult(0);
        }

        /// <summary>
        ///     Gets whether two factor authentication is enabled for the user
        /// </summary>
        /// <param name="user"></param>
        /// <param name="cancellationToken"></param>
        /// <returns></returns>
        public virtual Task<bool> GetTwoFactorEnabledAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
        {
            cancellationToken.ThrowIfCancellationRequested();
            ThrowIfDisposed();
            if (user == null)
            {
                throw new ArgumentNullException("user");
            }
            return Task.FromResult(user.TwoFactorEnabled);
        }

        private void ThrowIfDisposed()
        {
            if (_disposed)
            {
                throw new ObjectDisposedException(GetType().Name);
            }
        }

        /// <summary>
        ///     Dispose the store
        /// </summary>
        public void Dispose()
        {
            _disposed = true;
        }
    }
}