using System.Collections.Generic;
using Common.Base;
using Common.Event;
using Common.Helper;
using MongoDB.Bson;

namespace Model
{
	public class TimerComponent : Component<World>, IRunner
	{
		private class Timer
		{
			public ObjectId Id { get; set; }
			public long Time { get; set; }
			public int CallbackId { get; set; }
			public Env Env { get; set; }
		}

		private readonly Dictionary<ObjectId, Timer> timers = new Dictionary<ObjectId, Timer>();

		/// <summary>
		/// key: time, value: timer id
		/// </summary>
		private readonly MultiMap<long, ObjectId> timeId = new MultiMap<long, ObjectId>();

		private readonly Queue<long> timeoutTimer = new Queue<long>();

		public ObjectId Add(long time, int callbackId, Env env)
		{
			Timer timer = new Timer
			{
				Id = ObjectId.GenerateNewId(),
				Time = time,
				CallbackId = callbackId,
				Env = env
			};
			this.timers[timer.Id] = timer;
			this.timeId.Add(timer.Time, timer.Id);
			return timer.Id;
		}

		public void Remove(ObjectId id)
		{
			Timer timer;
			if (!this.timers.TryGetValue(id, out timer))
			{
				return;
			}
			this.timeId.Remove(timer.Time, timer.Id);
		}

		public void Run()
		{
			long timeNow = TimeHelper.Now();
			foreach (long time in this.timeId.Keys)
			{
				if (time > timeNow)
				{
					break;
				}
				timeoutTimer.Enqueue(time);
			}

			while (timeoutTimer.Count > 0)
			{
				long key = timeoutTimer.Dequeue();
				List<ObjectId> timeOutId = this.timeId[key];
				foreach (ObjectId id in timeOutId)
				{
					Timer timer;
					if (!this.timers.TryGetValue(id, out timer))
					{
						continue;
					}
					this.Remove(id);
					World.Instance.GetComponent<EventComponent<ActionAttribute>>()
							.Run(timer.CallbackId, timer.Env);
				}
			}
		}
	}
}