// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.Collections.Generic;
using System.Threading;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;

namespace Microsoft.AspNetCore.Identity
{
    /// <summary>
    /// Provides the APIs for managing user in a persistence store.
    /// </summary>
    /// <typeparam name="TUser">The type encapsulating a user.</typeparam>
    public class AspNetUserManager<TUser> : UserManager<TUser>, IDisposable where TUser : class
    {
        private readonly CancellationToken _cancel;

        /// <summary>
        /// Constructs a new instance of <see cref="AspNetUserManager{TUser}"/>.
        /// </summary>
        /// <param name="store">The persistence store the manager will operate over.</param>
        /// <param name="optionsAccessor">The accessor used to access the <see cref="IdentityOptions"/>.</param>
        /// <param name="passwordHasher">The password hashing implementation to use when saving passwords.</param>
        /// <param name="userValidators">A collection of <see cref="IUserValidator{TUser}"/> to validate users against.</param>
        /// <param name="passwordValidators">A collection of <see cref="IPasswordValidator{TUser}"/> to validate passwords against.</param>
        /// <param name="keyNormalizer">The <see cref="ILookupNormalizer"/> to use when generating index keys for users.</param>
        /// <param name="errors">The <see cref="IdentityErrorDescriber"/> used to provider error messages.</param>
        /// <param name="services">The <see cref="IServiceProvider"/> used to resolve services.</param>
        /// <param name="logger">The logger used to log messages, warnings and errors.</param>
        public AspNetUserManager(IUserStore<TUser> store,
            IOptions<IdentityOptions> optionsAccessor,
            IPasswordHasher<TUser> passwordHasher,
            IEnumerable<IUserValidator<TUser>> userValidators,
            IEnumerable<IPasswordValidator<TUser>> passwordValidators,
            ILookupNormalizer keyNormalizer,
            IdentityErrorDescriber errors,
            IServiceProvider services,
            ILogger<UserManager<TUser>> logger)
            : base(store, optionsAccessor, passwordHasher, userValidators, passwordValidators, keyNormalizer, errors, services, logger)
        {
            _cancel = services?.GetService<IHttpContextAccessor>()?.HttpContext?.RequestAborted ?? CancellationToken.None;
        }

        /// <summary>
        /// The cancellation token assocated with the current HttpContext.RequestAborted or CancellationToken.None if unavailable.
        /// </summary>
        protected override CancellationToken CancellationToken => _cancel;
   }
}