// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Linq;
using System.Security.Claims;
using Microsoft.EntityFrameworkCore;

namespace Microsoft.AspNetCore.Identity.EntityFrameworkCore;

/// <summary>
/// Represents a new instance of a persistence store for users, using the default implementation
/// of <see cref="IdentityUser{TKey}"/> with a string as a primary key.
/// </summary>
public class UserStore : UserStore<IdentityUser<string>>
{
    /// <summary>
    /// Constructs a new instance of <see cref="UserStore"/>.
    /// </summary>
    /// <param name="context">The <see cref="DbContext"/>.</param>
    /// <param name="describer">The <see cref="IdentityErrorDescriber"/>.</param>
    public UserStore(DbContext context, IdentityErrorDescriber? describer = null) : base(context, describer) { }
}

/// <summary>
/// Creates a new instance of a persistence store for the specified user type.
/// </summary>
/// <typeparam name="TUser">The type representing a user.</typeparam>
public class UserStore<TUser> : UserStore<TUser, IdentityRole, DbContext, string>
    where TUser : IdentityUser<string>, new()
{
    /// <summary>
    /// Constructs a new instance of <see cref="UserStore{TUser}"/>.
    /// </summary>
    /// <param name="context">The <see cref="DbContext"/>.</param>
    /// <param name="describer">The <see cref="IdentityErrorDescriber"/>.</param>
    public UserStore(DbContext context, IdentityErrorDescriber? describer = null) : base(context, describer) { }
}

/// <summary>
/// Represents a new instance of a persistence store for the specified user and role types.
/// </summary>
/// <typeparam name="TUser">The type representing a user.</typeparam>
/// <typeparam name="TRole">The type representing a role.</typeparam>
/// <typeparam name="TContext">The type of the data context class used to access the store.</typeparam>
public class UserStore<TUser, TRole, TContext> : UserStore<TUser, TRole, TContext, string>
    where TUser : IdentityUser<string>
    where TRole : IdentityRole<string>
    where TContext : DbContext
{
    /// <summary>
    /// Constructs a new instance of <see cref="UserStore{TUser, TRole, TContext}"/>.
    /// </summary>
    /// <param name="context">The <see cref="DbContext"/>.</param>
    /// <param name="describer">The <see cref="IdentityErrorDescriber"/>.</param>
    public UserStore(TContext context, IdentityErrorDescriber? describer = null) : base(context, describer) { }
}

/// <summary>
/// Represents a new instance of a persistence store for the specified user and role types.
/// </summary>
/// <typeparam name="TUser">The type representing a user.</typeparam>
/// <typeparam name="TRole">The type representing a role.</typeparam>
/// <typeparam name="TContext">The type of the data context class used to access the store.</typeparam>
/// <typeparam name="TKey">The type of the primary key for a role.</typeparam>
public class UserStore<TUser, TRole, TContext, TKey> : UserStore<TUser, TRole, TContext, TKey, IdentityUserClaim<TKey>, IdentityUserRole<TKey>, IdentityUserLogin<TKey>, IdentityUserToken<TKey>, IdentityRoleClaim<TKey>>
    where TUser : IdentityUser<TKey>
    where TRole : IdentityRole<TKey>
    where TContext : DbContext
    where TKey : IEquatable<TKey>
{
    /// <summary>
    /// Constructs a new instance of <see cref="UserStore{TUser, TRole, TContext, TKey}"/>.
    /// </summary>
    /// <param name="context">The <see cref="DbContext"/>.</param>
    /// <param name="describer">The <see cref="IdentityErrorDescriber"/>.</param>
    public UserStore(TContext context, IdentityErrorDescriber? describer = null) : base(context, describer) { }
}

/// <summary>
/// Represents a new instance of a persistence store for the specified user and role types.
/// </summary>
/// <typeparam name="TUser">The type representing a user.</typeparam>
/// <typeparam name="TRole">The type representing a role.</typeparam>
/// <typeparam name="TContext">The type of the data context class used to access the store.</typeparam>
/// <typeparam name="TKey">The type of the primary key for a role.</typeparam>
/// <typeparam name="TUserClaim">The type representing a claim.</typeparam>
/// <typeparam name="TUserRole">The type representing a user role.</typeparam>
/// <typeparam name="TUserLogin">The type representing a user external login.</typeparam>
/// <typeparam name="TUserToken">The type representing a user token.</typeparam>
/// <typeparam name="TRoleClaim">The type representing a role claim.</typeparam>
public class UserStore<TUser, TRole, TContext, [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] TKey, TUserClaim, TUserRole, TUserLogin, TUserToken, TRoleClaim> :
    UserStoreBase<TUser, TRole, TKey, TUserClaim, TUserRole, TUserLogin, TUserToken, TRoleClaim>,
    IProtectedUserStore<TUser>
    where TUser : IdentityUser<TKey>
    where TRole : IdentityRole<TKey>
    where TContext : DbContext
    where TKey : IEquatable<TKey>
    where TUserClaim : IdentityUserClaim<TKey>, new()
    where TUserRole : IdentityUserRole<TKey>, new()
    where TUserLogin : IdentityUserLogin<TKey>, new()
    where TUserToken : IdentityUserToken<TKey>, new()
    where TRoleClaim : IdentityRoleClaim<TKey>, new()
{
    /// <summary>
    /// Creates a new instance of the store.
    /// </summary>
    /// <param name="context">The context used to access the store.</param>
    /// <param name="describer">The <see cref="IdentityErrorDescriber"/> used to describe store errors.</param>
    public UserStore(TContext context, IdentityErrorDescriber? describer = null) : base(describer ?? new IdentityErrorDescriber())
    {
        ArgumentNullException.ThrowIfNull(context);
        Context = context;
    }

    /// <summary>
    /// Gets the database context for this store.
    /// </summary>
    public virtual TContext Context { get; private set; }

    private DbSet<TUser> UsersSet { get { return Context.Set<TUser>(); } }
    private DbSet<TRole> Roles { get { return Context.Set<TRole>(); } }
    private DbSet<TUserClaim> UserClaims { get { return Context.Set<TUserClaim>(); } }
    private DbSet<TUserRole> UserRoles { get { return Context.Set<TUserRole>(); } }
    private DbSet<TUserLogin> UserLogins { get { return Context.Set<TUserLogin>(); } }
    private DbSet<TUserToken> UserTokens { get { return Context.Set<TUserToken>(); } }

    /// <summary>
    /// Gets or sets a flag indicating if changes should be persisted after CreateAsync, UpdateAsync and DeleteAsync are called.
    /// </summary>
    /// <value>
    /// True if changes should be automatically persisted, otherwise false.
    /// </value>
    public bool AutoSaveChanges { get; set; } = true;

    /// <summary>Saves the current store.</summary>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    protected Task SaveChanges(CancellationToken cancellationToken)
    {
        return AutoSaveChanges ? Context.SaveChangesAsync(cancellationToken) : Task.CompletedTask;
    }

    /// <summary>
    /// Creates the specified <paramref name="user"/> in the user store.
    /// </summary>
    /// <param name="user">The user to create.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation, containing the <see cref="IdentityResult"/> of the creation operation.</returns>
    public override async Task<IdentityResult> CreateAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        Context.Add(user);
        await SaveChanges(cancellationToken);
        return IdentityResult.Success;
    }

    /// <summary>
    /// Updates the specified <paramref name="user"/> in the user store.
    /// </summary>
    /// <param name="user">The user to update.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation, containing the <see cref="IdentityResult"/> of the update operation.</returns>
    public override async Task<IdentityResult> UpdateAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);

        Context.Attach(user);
        user.ConcurrencyStamp = Guid.NewGuid().ToString();
        Context.Update(user);
        try
        {
            await SaveChanges(cancellationToken);
        }
        catch (DbUpdateConcurrencyException)
        {
            return IdentityResult.Failed(ErrorDescriber.ConcurrencyFailure());
        }
        return IdentityResult.Success;
    }

    /// <summary>
    /// Deletes the specified <paramref name="user"/> from the user store.
    /// </summary>
    /// <param name="user">The user to delete.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation, containing the <see cref="IdentityResult"/> of the update operation.</returns>
    public override async Task<IdentityResult> DeleteAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);

        Context.Remove(user);
        try
        {
            await SaveChanges(cancellationToken);
        }
        catch (DbUpdateConcurrencyException)
        {
            return IdentityResult.Failed(ErrorDescriber.ConcurrencyFailure());
        }
        return IdentityResult.Success;
    }

    /// <summary>
    /// Finds and returns a user, if any, who has the specified <paramref name="userId"/>.
    /// </summary>
    /// <param name="userId">The user ID to search for.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>
    /// The <see cref="Task"/> that represents the asynchronous operation, containing the user matching the specified <paramref name="userId"/> if it exists.
    /// </returns>
    public override Task<TUser?> FindByIdAsync(string userId, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        var id = ConvertIdFromString(userId);
        return UsersSet.FindAsync(new object?[] { id }, cancellationToken).AsTask();
    }

    /// <summary>
    /// Finds and returns a user, if any, who has the specified normalized user name.
    /// </summary>
    /// <param name="normalizedUserName">The normalized user name to search for.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>
    /// The <see cref="Task"/> that represents the asynchronous operation, containing the user matching the specified <paramref name="normalizedUserName"/> if it exists.
    /// </returns>
    public override Task<TUser?> FindByNameAsync(string normalizedUserName, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();

        return Users.FirstOrDefaultAsync(u => u.NormalizedUserName == normalizedUserName, cancellationToken);
    }

    /// <summary>
    /// A navigation property for the users the store contains.
    /// </summary>
    public override IQueryable<TUser> Users
    {
        get { return UsersSet; }
    }

    /// <summary>
    /// Return a role with the normalized name if it exists.
    /// </summary>
    /// <param name="normalizedRoleName">The normalized role name.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The role if it exists.</returns>
    protected override Task<TRole?> FindRoleAsync(string normalizedRoleName, CancellationToken cancellationToken)
    {
        return Roles.SingleOrDefaultAsync(r => r.NormalizedName == normalizedRoleName, cancellationToken);
    }

    /// <summary>
    /// Return a user role for the userId and roleId if it exists.
    /// </summary>
    /// <param name="userId">The user's id.</param>
    /// <param name="roleId">The role's id.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The user role if it exists.</returns>
    protected override Task<TUserRole?> FindUserRoleAsync(TKey userId, TKey roleId, CancellationToken cancellationToken)
    {
        return UserRoles.FindAsync(new object[] { userId, roleId }, cancellationToken).AsTask();
    }

    /// <summary>
    /// Return a user with the matching userId if it exists.
    /// </summary>
    /// <param name="userId">The user's id.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The user if it exists.</returns>
    protected override Task<TUser?> FindUserAsync(TKey userId, CancellationToken cancellationToken)
    {
        return Users.SingleOrDefaultAsync(u => u.Id.Equals(userId), cancellationToken);
    }

    /// <summary>
    /// Return a user login with the matching userId, provider, providerKey if it exists.
    /// </summary>
    /// <param name="userId">The user's id.</param>
    /// <param name="loginProvider">The login provider name.</param>
    /// <param name="providerKey">The key provided by the <paramref name="loginProvider"/> to identify a user.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The user login if it exists.</returns>
    protected override Task<TUserLogin?> FindUserLoginAsync(TKey userId, string loginProvider, string providerKey, CancellationToken cancellationToken)
    {
        return UserLogins.SingleOrDefaultAsync(userLogin => userLogin.UserId.Equals(userId) && userLogin.LoginProvider == loginProvider && userLogin.ProviderKey == providerKey, cancellationToken);
    }

    /// <summary>
    /// Return a user login with  provider, providerKey if it exists.
    /// </summary>
    /// <param name="loginProvider">The login provider name.</param>
    /// <param name="providerKey">The key provided by the <paramref name="loginProvider"/> to identify a user.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The user login if it exists.</returns>
    protected override Task<TUserLogin?> FindUserLoginAsync(string loginProvider, string providerKey, CancellationToken cancellationToken)
    {
        return UserLogins.SingleOrDefaultAsync(userLogin => userLogin.LoginProvider == loginProvider && userLogin.ProviderKey == providerKey, cancellationToken);
    }

    /// <summary>
    /// Adds the given <paramref name="normalizedRoleName"/> to the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user to add the role to.</param>
    /// <param name="normalizedRoleName">The role to add.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    public override async Task AddToRoleAsync(TUser user, string normalizedRoleName, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        if (string.IsNullOrWhiteSpace(normalizedRoleName))
        {
            throw new ArgumentException(Resources.ValueCannotBeNullOrEmpty, nameof(normalizedRoleName));
        }
        var roleEntity = await FindRoleAsync(normalizedRoleName, cancellationToken);
        if (roleEntity == null)
        {
            throw new InvalidOperationException(string.Format(CultureInfo.CurrentCulture, Resources.RoleNotFound, normalizedRoleName));
        }
        UserRoles.Add(CreateUserRole(user, roleEntity));
    }

    /// <summary>
    /// Removes the given <paramref name="normalizedRoleName"/> from the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user to remove the role from.</param>
    /// <param name="normalizedRoleName">The role to remove.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    public override async Task RemoveFromRoleAsync(TUser user, string normalizedRoleName, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        if (string.IsNullOrWhiteSpace(normalizedRoleName))
        {
            throw new ArgumentException(Resources.ValueCannotBeNullOrEmpty, nameof(normalizedRoleName));
        }
        var roleEntity = await FindRoleAsync(normalizedRoleName, cancellationToken);
        if (roleEntity != null)
        {
            var userRole = await FindUserRoleAsync(user.Id, roleEntity.Id, cancellationToken);
            if (userRole != null)
            {
                UserRoles.Remove(userRole);
            }
        }
    }

    /// <summary>
    /// Retrieves the roles the specified <paramref name="user"/> is a member of.
    /// </summary>
    /// <param name="user">The user whose roles should be retrieved.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>A <see cref="Task{TResult}"/> that contains the roles the user is a member of.</returns>
    public override async Task<IList<string>> GetRolesAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        var userId = user.Id;
        var query = from userRole in UserRoles
                    join role in Roles on userRole.RoleId equals role.Id
                    where userRole.UserId.Equals(userId)
                    select role.Name;
        return await query.ToListAsync(cancellationToken);
    }

    /// <summary>
    /// Returns a flag indicating if the specified user is a member of the give <paramref name="normalizedRoleName"/>.
    /// </summary>
    /// <param name="user">The user whose role membership should be checked.</param>
    /// <param name="normalizedRoleName">The role to check membership of</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>A <see cref="Task{TResult}"/> containing a flag indicating if the specified user is a member of the given group. If the
    /// user is a member of the group the returned value with be true, otherwise it will be false.</returns>
    public override async Task<bool> IsInRoleAsync(TUser user, string normalizedRoleName, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        if (string.IsNullOrWhiteSpace(normalizedRoleName))
        {
            throw new ArgumentException(Resources.ValueCannotBeNullOrEmpty, nameof(normalizedRoleName));
        }
        var role = await FindRoleAsync(normalizedRoleName, cancellationToken);
        if (role != null)
        {
            var userRole = await FindUserRoleAsync(user.Id, role.Id, cancellationToken);
            return userRole != null;
        }
        return false;
    }

    /// <summary>
    /// Get the claims associated with the specified <paramref name="user"/> as an asynchronous operation.
    /// </summary>
    /// <param name="user">The user whose claims should be retrieved.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>A <see cref="Task{TResult}"/> that contains the claims granted to a user.</returns>
    public override async Task<IList<Claim>> GetClaimsAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
    {
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);

        return await UserClaims.Where(uc => uc.UserId.Equals(user.Id)).Select(c => c.ToClaim()).ToListAsync(cancellationToken);
    }

    /// <summary>
    /// Adds the <paramref name="claims"/> given to the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user to add the claim to.</param>
    /// <param name="claims">The claim to add to the user.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    public override Task AddClaimsAsync(TUser user, IEnumerable<Claim> claims, CancellationToken cancellationToken = default(CancellationToken))
    {
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        ArgumentNullException.ThrowIfNull(claims);
        foreach (var claim in claims)
        {
            UserClaims.Add(CreateUserClaim(user, claim));
        }
        return Task.FromResult(false);
    }

    /// <summary>
    /// Replaces the <paramref name="claim"/> on the specified <paramref name="user"/>, with the <paramref name="newClaim"/>.
    /// </summary>
    /// <param name="user">The user to replace the claim on.</param>
    /// <param name="claim">The claim replace.</param>
    /// <param name="newClaim">The new claim replacing the <paramref name="claim"/>.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    public override async Task ReplaceClaimAsync(TUser user, Claim claim, Claim newClaim, CancellationToken cancellationToken = default(CancellationToken))
    {
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        ArgumentNullException.ThrowIfNull(claim);
        ArgumentNullException.ThrowIfNull(newClaim);

        var matchedClaims = await UserClaims.Where(uc => uc.UserId.Equals(user.Id) && uc.ClaimValue == claim.Value && uc.ClaimType == claim.Type).ToListAsync(cancellationToken);
        foreach (var matchedClaim in matchedClaims)
        {
            matchedClaim.ClaimValue = newClaim.Value;
            matchedClaim.ClaimType = newClaim.Type;
        }
    }

    /// <summary>
    /// Removes the <paramref name="claims"/> given from the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user to remove the claims from.</param>
    /// <param name="claims">The claim to remove.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    public override async Task RemoveClaimsAsync(TUser user, IEnumerable<Claim> claims, CancellationToken cancellationToken = default(CancellationToken))
    {
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        ArgumentNullException.ThrowIfNull(claims);
        foreach (var claim in claims)
        {
            var matchedClaims = await UserClaims.Where(uc => uc.UserId.Equals(user.Id) && uc.ClaimValue == claim.Value && uc.ClaimType == claim.Type).ToListAsync(cancellationToken);
            foreach (var c in matchedClaims)
            {
                UserClaims.Remove(c);
            }
        }
    }

    /// <summary>
    /// Adds the <paramref name="login"/> given to the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user to add the login to.</param>
    /// <param name="login">The login to add to the user.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    public override Task AddLoginAsync(TUser user, UserLoginInfo login,
        CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        ArgumentNullException.ThrowIfNull(login);
        UserLogins.Add(CreateUserLogin(user, login));
        return Task.FromResult(false);
    }

    /// <summary>
    /// Removes the <paramref name="loginProvider"/> given from the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user to remove the login from.</param>
    /// <param name="loginProvider">The login to remove from the user.</param>
    /// <param name="providerKey">The key provided by the <paramref name="loginProvider"/> to identify a user.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The <see cref="Task"/> that represents the asynchronous operation.</returns>
    public override async Task RemoveLoginAsync(TUser user, string loginProvider, string providerKey,
        CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        var entry = await FindUserLoginAsync(user.Id, loginProvider, providerKey, cancellationToken);
        if (entry != null)
        {
            UserLogins.Remove(entry);
        }
    }

    /// <summary>
    /// Retrieves the associated logins for the specified <param ref="user"/>.
    /// </summary>
    /// <param name="user">The user whose associated logins to retrieve.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>
    /// The <see cref="Task"/> for the asynchronous operation, containing a list of <see cref="UserLoginInfo"/> for the specified <paramref name="user"/>, if any.
    /// </returns>
    public override async Task<IList<UserLoginInfo>> GetLoginsAsync(TUser user, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(user);
        var userId = user.Id;
        return await UserLogins.Where(l => l.UserId.Equals(userId))
            .Select(l => new UserLoginInfo(l.LoginProvider, l.ProviderKey, l.ProviderDisplayName)).ToListAsync(cancellationToken);
    }

    /// <summary>
    /// Retrieves the user associated with the specified login provider and login provider key.
    /// </summary>
    /// <param name="loginProvider">The login provider who provided the <paramref name="providerKey"/>.</param>
    /// <param name="providerKey">The key provided by the <paramref name="loginProvider"/> to identify a user.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>
    /// The <see cref="Task"/> for the asynchronous operation, containing the user, if any which matched the specified login provider and key.
    /// </returns>
    public override async Task<TUser?> FindByLoginAsync(string loginProvider, string providerKey,
        CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        var userLogin = await FindUserLoginAsync(loginProvider, providerKey, cancellationToken);
        if (userLogin != null)
        {
            return await FindUserAsync(userLogin.UserId, cancellationToken);
        }
        return null;
    }

    /// <summary>
    /// Gets the user, if any, associated with the specified, normalized email address.
    /// </summary>
    /// <param name="normalizedEmail">The normalized email address to return the user for.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>
    /// The task object containing the results of the asynchronous lookup operation, the user if any associated with the specified normalized email address.
    /// </returns>
    public override Task<TUser?> FindByEmailAsync(string normalizedEmail, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();

        return Users.SingleOrDefaultAsync(u => u.NormalizedEmail == normalizedEmail, cancellationToken);
    }

    /// <summary>
    /// Retrieves all users with the specified claim.
    /// </summary>
    /// <param name="claim">The claim whose users should be retrieved.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>
    /// The <see cref="Task"/> contains a list of users, if any, that contain the specified claim.
    /// </returns>
    public override async Task<IList<TUser>> GetUsersForClaimAsync(Claim claim, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentNullException.ThrowIfNull(claim);

        var query = from userclaims in UserClaims
                    join user in Users on userclaims.UserId equals user.Id
                    where userclaims.ClaimValue == claim.Value
                    && userclaims.ClaimType == claim.Type
                    select user;

        return await query.ToListAsync(cancellationToken);
    }

    /// <summary>
    /// Retrieves all users in the specified role.
    /// </summary>
    /// <param name="normalizedRoleName">The role whose users should be retrieved.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>
    /// The <see cref="Task"/> contains a list of users, if any, that are in the specified role.
    /// </returns>
    public override async Task<IList<TUser>> GetUsersInRoleAsync(string normalizedRoleName, CancellationToken cancellationToken = default(CancellationToken))
    {
        cancellationToken.ThrowIfCancellationRequested();
        ThrowIfDisposed();
        ArgumentException.ThrowIfNullOrEmpty(normalizedRoleName);

        var role = await FindRoleAsync(normalizedRoleName, cancellationToken);

        if (role != null)
        {
            var query = from userrole in UserRoles
                        join user in Users on userrole.UserId equals user.Id
                        where userrole.RoleId.Equals(role.Id)
                        select user;

            return await query.ToListAsync(cancellationToken);
        }
        return new List<TUser>();
    }

    /// <summary>
    /// Find a user token if it exists.
    /// </summary>
    /// <param name="user">The token owner.</param>
    /// <param name="loginProvider">The login provider for the token.</param>
    /// <param name="name">The name of the token.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The user token if it exists.</returns>
    protected override Task<TUserToken?> FindTokenAsync(TUser user, string loginProvider, string name, CancellationToken cancellationToken)
        => UserTokens.FindAsync(new object[] { user.Id, loginProvider, name }, cancellationToken).AsTask();

    /// <summary>
    /// Add a new user token.
    /// </summary>
    /// <param name="token">The token to be added.</param>
    /// <returns></returns>
    protected override Task AddUserTokenAsync(TUserToken token)
    {
        UserTokens.Add(token);
        return Task.CompletedTask;
    }

    /// <summary>
    /// Remove a new user token.
    /// </summary>
    /// <param name="token">The token to be removed.</param>
    /// <returns></returns>
    protected override Task RemoveUserTokenAsync(TUserToken token)
    {
        UserTokens.Remove(token);
        return Task.CompletedTask;
    }
}
