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

namespace Applications.Session
{
    public class SessionEngine
    {
        public SessionEngine()
        {
            Load();
        }

        List<SessionInfo> SessionList = null;//会话列表

        System.Timers.Timer tmr = null;

        /// <summary>
        /// 装载服务定义
        /// </summary>
        private void Load()
        {
            tmr = new System.Timers.Timer();
            tmr.Interval = 60000;
            tmr.Elapsed += new System.Timers.ElapsedEventHandler(tmr_Elapsed);
            tmr.Start();
        }

        /// <summary>
        /// 处理过期的会话
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void tmr_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
        {
            TimeSpan ts = Common.TextUtil.DateTimeUtil.DateDiff(DateTime.Now);
            var s = SessionList.FindAll(p => Common.TextUtil.DateTimeUtil.DateDiff(p.UpdateTime).TotalMinutes > 20);
            for (int i = s.Count; i >= 0; i--)
            {
                SessionList.RemoveAt(i);
            }
        }

        /// <summary>
        /// 向会话中添加用户，已存在时更新会话
        /// </summary>
        /// <param name="user">用户会话信息</param>
        public void AddUser(SessionInfo user)
        {
            user.LogonTime = DateTime.Now;
            user.UpdateTime = DateTime.Now;

            var s = SessionList.Find(p => p.IP == user.IP);
            if (s == null)
            {
                SessionList.Add(user);
            }
            else
            {
                if (s.UserName == user.UserName)
                {
                    s.Port = user.Port;
                    s.UpdateTime = DateTime.Now;
                }
                else
                {
                    SessionList.Remove(s);
                    SessionList.Add(user);
                }
            }
        }

        /// <summary>
        /// 注销指定用户的会话状态
        /// </summary>
        /// <param name="user">用户会话信息</param>
        public void RemoveUser(SessionInfo user)
        {
            var s = SessionList.Find(p => p.IP == user.IP);
            if (s != null)
            {
                SessionList.Remove(s);
            }
        }

        /// <summary>
        /// 查找指定用户
        /// </summary>
        /// <param name="userName">用户姓名</param>
        /// <returns></returns>
        public SessionInfo FindUser(string userName)
        {
            return SessionList.Find(p => p.UserName == userName);
        }
    }
}