using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.IO;
using System.Reflection;
using System.Diagnostics;

namespace SellTicketsSynchronously
{
    class Program
    {
        //入口
        static void Main(string[] args)
        {
            Ticket tc = new Ticket(10);
            Task t1 = new Task(() => { CallWithAsync(tc); });
            t1.ContinueWith(t => { Console.WriteLine("Tickets has been sold out. Press any key to quit:"); });
            t1.Start();
            Console.ReadLine();
        }
        //调用异步方法
        private static void CallWithAsync(Ticket tc) 
        {
            Task.Run(() =>
            {
                Task.Run(() => { SellTicket("Window1", tc); });
                Task.Run(() => { SellTicket("Window2", tc); });
                Task.Run(() => { SellTicket("Window3", tc); });
                Task.Run(() => { SellTicket("Window4", tc); });
            });
        }
        //卖票方法
        public static void SellTicket(string windowName, object obj) 
        {
            string nameOfWindow = windowName;
            Ticket ticket = obj as Ticket;
            while (ticket.NumOfTickets > 0)
            {
                lock (ticket)
                {
                    if (ticket.NumOfTickets > 0)
                    {
                        try
                        {
                            ticket.NumOfTickets--;
                            Console.WriteLine(DateTime.Now.ToString() + ":" + nameOfWindow + " sells a ticket, " + ticket.NumOfTickets + " tickets left.");
                        }
                        catch (Exception ex)
                        {
                            WriteLog(ex);
                        }
                    }
                }
                Random random = new Random();
                Thread.Sleep(random.Next(100,500));
            }
        }
        //打log方法
        private static void WriteLog(Exception ex)
        {
            string logUrl = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) + "\\SellTicketslog.txt";
            if (File.Exists(@logUrl))
            {
                using (FileStream fs = new FileStream(logUrl, FileMode.Append))
                {
                    using (StreamWriter sw = new StreamWriter(fs, Encoding.Default))
                    {
                        try
                        {
                            sw.Write(ex);
                        }
                        catch (Exception ex1)
                        {
                            WriteLog(ex1);
                        }
                        finally
                        {
                            sw.Close();
                            fs.Close();
                        }
                    }
                }
            }
            else
            {
                using (FileStream fs = new FileStream(logUrl, FileMode.CreateNew))
                {
                    using (StreamWriter sw = new StreamWriter(fs, Encoding.Default))
                    {
                        try
                        {
                            sw.Write(ex);
                        }
                        catch (Exception ex1)
                        {
                            WriteLog(ex1);
                        }
                        finally
                        {
                            sw.Close();
                            fs.Close();
                        }
                    }
                }
            }
        }
    }
    //票类
    class Ticket 
    {
        public int NumOfTickets { get; set; }
        public Ticket(int num) 
        {
            this.NumOfTickets = num;
        }
    }
}