using System;

using System.Collections.Generic;

using System.Threading;

using System.Linq;

​

public class Ticket

{

    private const int MSEC_TIME_EXTEND =  1000;

    public enum TicketState: int { Unknown = 0, Queueing = 1, Serve = 2, Thrown = 3, Expired = 4};

    private TicketState _state;

    private int _id;

    public int ID

    {

        get

        {

            return _id;

        }

    }

    public DateTime BookTime;

    public DateTime ServeTime;    

    public DateTime ExpiryTime;

    public Ticket()

    {

        _state = TicketState.Unknown; _id = 0; BookTime = DateTime.MinValue;

        ServeTime = DateTime.MinValue; ExpiryTime = DateTime.MinValue;

    }

    public Ticket(int id)

    :this()

    {

        _id = id; BookTime = DateTime.Now; _state = TicketState.Queueing; 

    }

​

    public TicketState State

    {

        get{

            if (_state == TicketState.Serve)

            {

                if (ExpiryTime < DateTime.Now)

                {

                    _state  = TicketState.Expired;

                }

            }

            return _state;

        }

        set{

            switch(value)

            {

                case TicketState.Serve:

                    ServeTime = DateTime.Now;

                    ExpiryTime = DateTime.Now.AddMilliseconds(MSEC_TIME_EXTEND);                    

                    break;

            }

            _state = value;

        }

    }

    private static Dictionary<int, Ticket> _tickets = new Dictionary<int, Ticket>();

    private static Random _rand = new Random();

    private static int TicketIDToServe = 0;    

    public static int NumOfTickets

    {

        get{

            return _tickets.Count;

        }

    }

    public static TicketState CurrentTicketState

    {

        get{

            if (_tickets.Count == 0) return TicketState.Unknown;

            checkNextTicketsToServe();

            return _tickets.ContainsKey(TicketIDToServe) ? _tickets[TicketIDToServe].State : TicketState.Unknown;    

        }

    }

    public static int GetTicket()

    {

        int id = _rand.Next(1, int.MaxValue); //for ints

        while(_tickets.ContainsKey(id)) id = _rand.Next(1, int.MaxValue);

        _tickets.Add(id, new Ticket(id));

        return id;

    }

​

    public static TicketState CheckTicketState(int id)

    {

        checkNextTicketsToServe();

​

        // Trash thrown tickets

        trashThrownTickets();

​

        // Throw Expired tickets

        checkExpiredTicketsToThrow();

​

        // Check tickets expired

        checkTicketsExpired();

​

        return _tickets.ContainsKey(id) ? _tickets[id].State : TicketState.Unknown; 

    }

​

    private static void checkNextTicketsToServe()

    {

        if (!_tickets.ContainsKey(TicketIDToServe)) 

            TicketIDToServe = 0;

        else if (_tickets[TicketIDToServe].State != TicketState.Serve)

            TicketIDToServe = 0;

        if (!_tickets.ContainsKey(TicketIDToServe))

        {

            DateTime minBookTime = DateTime.MaxValue; 

            foreach (KeyValuePair<int, Ticket> kvp in _tickets)

            {

                if(kvp.Value.State == TicketState.Queueing && minBookTime > kvp.Value.BookTime)

                {

                    minBookTime = kvp.Value.BookTime;

                    TicketIDToServe = kvp.Key;

                    break;

                }    

            }

            if (_tickets.ContainsKey(TicketIDToServe))

                _tickets[TicketIDToServe].State = TicketState.Serve;

        }   

    }

​

    private static void checkTicketsExpired()

    {

        int[] ids = _tickets.Where(t => t.Value.State == TicketState.Serve && t.Value.ExpiryTime < DateTime.Now).Select(t => t.Key).ToArray();

        foreach(int id in ids) _tickets[id].State = TicketState.Expired;

    }

​

    private static void checkExpiredTicketsToThrow()

    {

        int[] ids = _tickets.Where(t => t.Value.State == TicketState.Expired).Select(t => t.Key).ToArray();

        foreach(int id in ids) _tickets[id].State = TicketState.Thrown;

    }

    private static void trashThrownTickets()

    {

        int[] ids = _tickets.Where(t => t.Value.State == TicketState.Thrown).Select(t => t.Key).ToArray();

        foreach(int id in ids) _tickets.Remove(id);

    }

​

    public static void ExtendExpiryTime(int id)

    {

        if(!_tickets.ContainsKey(id)) return;

        if(_tickets[id].State != TicketState.Serve) return;        

        _tickets[id].ExpiryTime = DateTime.Now.AddMilliseconds(MSEC_TIME_EXTEND);

    }

​

    public static void ThrowTicket(int id)

    {

        if(!_tickets.ContainsKey(id)) return;

        if(_tickets[id].State != TicketState.Serve) return;        

        _tickets[id].State = TicketState.Thrown;

        if (TicketIDToServe == id) TicketIDToServe = 0;

    }

​

    public static void CancelTicket(int id)

    {

        if(!_tickets.ContainsKey(id)) return;    

        switch(_tickets[id].State)

        {

          case TicketState.Queueing:

          case TicketState.Serve:

            _tickets[id].State = TicketState.Thrown;

            if (TicketIDToServe == id) TicketIDToServe = 0;

            break;

        }

    }   

}

​

public class HelloConsole

{

    public static void Main(string[] args)

    {

        (new Thread(new ThreadStart(threadLoop))).Start();

        Console.WriteLine ("Hello Mono World");

​

        while(Console.ReadKey().KeyChar != 'q')

        {

            doIt();

        }

​

    }

​

    private static void threadLoop()

    {

        while(true)

        {

            if (Ticket.CurrentTicketState == Ticket.TicketState.Unknown)

            {

                Console.WriteLine("{0} do loop", DateTime.Now.ToString("HH:mm:ss.fff"));            

            }

            Thread.Sleep(500);

        }       

    }

​

    private static void doIt()

    {

        int id = Ticket.GetTicket();

        while(Ticket.CheckTicketState(id) != Ticket.TicketState.Serve) Thread.Sleep(100);        

        Ticket.ExtendExpiryTime(id);

        Console.WriteLine("{0} do task", DateTime.Now.ToString("HH:mm:ss.fff"));

        Ticket.ThrowTicket(id);

    }

}