using System;
using System.Collections.Generic;
using System.Threading;

namespace Kingo.ThreadManager
{
    public class ProcessManager
    {
        public static ProcessManager Instance { get; } = new ProcessManager();
        private static readonly object lockObj = new object();
        private List<CustomProcess> ProcessList = new List<CustomProcess>();
        public string WorkerPath { get; set; }
        private int _MaxThreadNum = -1;
        public int MaxThreadNum
        {
            get
            {
                if (_MaxThreadNum == -1)
                {
                    _MaxThreadNum = Environment.ProcessorCount - 2;
                }
                return _MaxThreadNum;
            }
            set
            {
                _MaxThreadNum = value;
            }
        }
        private ProcessManager() { }
        public void ExeTask(string pParm, ProcessHandler ProcessCallback = null)
        {
            var work = FindWorker();
            if (work != null)
            {
                try
                {
                    work.ExeTask(pParm, ProcessCallback);
                }
                catch (Exception ex)
                {

                }
            }
            else
            {

            }
        }
        public CustomProcess FindWorker()
        {
            lock (lockObj)
            {
                Thread.Sleep(1000);
                //移除所有的退出的work
                ProcessList.RemoveAll(p => p.IsExited);
                foreach (var item in ProcessList)
                {
                    if (item.IsExited)
                    {
                        continue;
                    }
                    if (!item.IsBusy)
                    {
                        return item;
                    }
                }
                //再移除一次
                ProcessList.RemoveAll(p => p.IsExited);
                if (ProcessList.Count < this.MaxThreadNum)
                {
                    CustomProcess newWork = new CustomProcess(WorkerPath);
                    ProcessList.Add(newWork);
                    return newWork;
                }
                return null;
            }
        }
    }
}