using System;
using System.Collections.Generic;
using System.Threading;
using System.Diagnostics;
using System.Linq;

using Sog;
using Sog.IO;
using Google.Protobuf.WellKnownTypes;

namespace SMAgent
{
	public enum ProcType
	{
		ProcType_NotRunning = 0, //初始是未启动的,只有从 running 到 notrunning 才需要短信通知
		ProcType_Running = 1,
	}

	public class CheckServerStat
    {
        public uint serverId;
		public ProcType procType = ProcType.ProcType_NotRunning;
	}

    public class SMAgentCheckProcStat : Singleton<SMAgentCheckProcStat>
    {
        private Thread m_workThread;

		// 当前正在监控的server app
		private List<CheckServerStat> m_serverProc = new List<CheckServerStat>();

        // 需要添加监控的server app
        private object m_serverProcAsyncLocker = new object();
		private List<uint> m_serverProcAsyncAdd = new List<uint>();

		private string m_workPath;


		private void CheckStart()
        {
            if (m_workThread == null)
            {
                m_workThread = new Thread(WorkThreadFun);
                m_workThread.Start();
            }
        }

        private void UpdateServerProcList()
        {
            lock (m_serverProcAsyncLocker)
            {
                if (m_serverProcAsyncAdd.Count > 0)
                {
                    List<CheckServerStat> temp = new List<CheckServerStat>();

                    foreach (uint serverId in m_serverProcAsyncAdd)
                    {
                        CheckServerStat proc = m_serverProc.FirstOrDefault(p => p.serverId == serverId);
                        if (proc != null)
                        {
                            temp.Add(proc);
                        }
                        else
                        {
                            temp.Add(new CheckServerStat { serverId = serverId });
                        }
                    }

                    m_serverProcAsyncAdd.Clear();
                    m_serverProc = temp;
				}
			}
		}

		private void WorkThreadFun()
        {
            while(true)
            {
                if (m_serverProcAsyncAdd.Count > 0)
                {
                    UpdateServerProcList();
                }

				foreach (var proc in m_serverProc)
				{
					if (CheckSogLoaderIsRunning(proc.serverId))
					{
						proc.procType = ProcType.ProcType_Running;
					}
					else if (proc.procType == ProcType.ProcType_Running)
					{
                        // todo 进程停止时, 如果不是执行stop命令, 发送告警短信, 要不要自动拉起?

                        proc.procType = ProcType.ProcType_NotRunning;
                    }
                }

				Thread.Sleep(1000);
			}
        }


        public void OnClientRegRes(SMClientRegRes regRes)
        {
	        lock (m_serverProcAsyncLocker)
	        {
				// 每次注册成功刷新监控列表
                m_serverProcAsyncAdd.Clear();
				m_serverProcAsyncAdd.AddRange(regRes.ServerId);
            }

			m_workPath = regRes.Workpath;
	       	        
			//开启工作线程
			CheckStart();
        }

		/// <summary>
		/// 检测下服务器的状态
		/// </summary>
		/// <param name="serverId"></param>
		/// <returns></returns>
		private bool CheckSogLoaderIsRunning(uint serverId)
        {
            ShareMemoryCommand shareCommand = null;
			try
            {
                shareCommand = new ShareMemoryCommand(m_workPath, serverId);

                bool attachSuccess = shareCommand.Attach();
                if (attachSuccess == false)
                {
					return false;
                }

                int procId = shareCommand.ReadProcessId();
                if(procId <= 0)
                {
					return false;
                }

                using (Process proc = Process.GetProcesses().FirstOrDefault(p => p.Id == procId))
                {
                    if (proc == null || proc.HasExited || proc.ProcessName != "SogLoader")
                    {
						return false;
                    }
					return true;
                }
            }
            catch(Exception ex)
			{
                TraceLog.Exception(ex);
				return false;
			}
            finally
			{
				shareCommand?.Close();
			}
        }

	}
}