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

using System.Threading;
using System.Threading.Tasks;

namespace Microsoft.AspNetCore.Identity;

/// <summary>
/// Provides an abstraction for the storage and management of user email addresses.
/// </summary>
/// <typeparam name="TUser">The type encapsulating a user.</typeparam>
public interface IUserEmailStore<TUser> : IUserStore<TUser> where TUser : class
{
    /// <summary>
    /// Sets the <paramref name="email"/> address for a <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user whose email should be set.</param>
    /// <param name="email">The email to set.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The task object representing the asynchronous operation.</returns>
    Task SetEmailAsync(TUser user, string? email, CancellationToken cancellationToken);

    /// <summary>
    /// Gets the email address for the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user whose email should be returned.</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 operation, the email address for the specified <paramref name="user"/>.</returns>
    Task<string?> GetEmailAsync(TUser user, CancellationToken cancellationToken);

    /// <summary>
    /// Gets a flag indicating whether the email address for the specified <paramref name="user"/> has been verified, true if the email address is verified otherwise
    /// false.
    /// </summary>
    /// <param name="user">The user whose email confirmation status should be returned.</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 operation, a flag indicating whether the email address for the specified <paramref name="user"/>
    /// has been confirmed or not.
    /// </returns>
    Task<bool> GetEmailConfirmedAsync(TUser user, CancellationToken cancellationToken);

    /// <summary>
    /// Sets the flag indicating whether the specified <paramref name="user"/>'s email address has been confirmed or not.
    /// </summary>
    /// <param name="user">The user whose email confirmation status should be set.</param>
    /// <param name="confirmed">A flag indicating if the email address has been confirmed, true if the address is confirmed otherwise false.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The task object representing the asynchronous operation.</returns>
    Task SetEmailConfirmedAsync(TUser user, bool confirmed, CancellationToken cancellationToken);

    /// <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>
    Task<TUser?> FindByEmailAsync(string normalizedEmail, CancellationToken cancellationToken);

    /// <summary>
    /// Returns the normalized email for the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user whose email address to retrieve.</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 normalized email address if any associated with the specified user.
    /// </returns>
    Task<string?> GetNormalizedEmailAsync(TUser user, CancellationToken cancellationToken);

    /// <summary>
    /// Sets the normalized email for the specified <paramref name="user"/>.
    /// </summary>
    /// <param name="user">The user whose email address to set.</param>
    /// <param name="normalizedEmail">The normalized email to set for the specified <paramref name="user"/>.</param>
    /// <param name="cancellationToken">The <see cref="CancellationToken"/> used to propagate notifications that the operation should be canceled.</param>
    /// <returns>The task object representing the asynchronous operation.</returns>
    Task SetNormalizedEmailAsync(TUser user, string? normalizedEmail, CancellationToken cancellationToken);
}
