using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using OAuth2Study.Model;

namespace OAuth2Study.IDal
{
    public interface UserIDal
    {
        /// <summary>
        /// 添加用户
        /// </summary>
        /// <param name="user">用户</param>
        /// <returns>ValueTuple</returns>
        (bool result, User user) AddUser(User user);

        /// <summary>
        /// 更新用户
        /// </summary>
        (bool result, User user) UpdateUser(User user);

        /// <summary>
        /// 删除用户
        /// </summary>
        bool RemoveUser(User user);

        /// <summary>
        /// 删除用户
        /// </summary>
        bool RemoveUser(int userId);

        /// <summary>
        /// 获取所有用户
        /// </summary>
        IQueryable<User> GetUsers();

        /// <summary>
        /// 查询用户
        /// </summary>
        IQueryable<User> GetUsers(Func<User,bool> predicate);

        /// <summary>
        /// 按Id查询用户
        /// </summary>
        User GetUser(int userId);

        /// <summary>
        /// 用户名是否存在
        /// </summary>
        bool ExitsByName(string userName);
    }
}