using QSB.Messaging;
using QSB.Player;
using QSB.TriggerSync.Messages;
using QSB.WorldSync;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;

namespace QSB.TriggerSync.WorldObjects
{
	public interface IQSBTrigger : IWorldObject
	{
		List<PlayerInfo> Occupants { get; }

		void Enter(PlayerInfo player);

		void Exit(PlayerInfo player);
	}

	public abstract class QSBTrigger<TO> : WorldObject<OWTriggerVolume>, IQSBTrigger
	{
		public TO TriggerOwner { get; init; }

		public List<PlayerInfo> Occupants { get; } = new();

		protected virtual string CompareTag => "PlayerDetector";

		public override void Init()
		{
			AttachedObject.OnEntry += OnEnterEvent;
			AttachedObject.OnExit += OnExitEvent;

			QSBPlayerManager.OnRemovePlayer += OnPlayerLeave;

			QSBCore.UnityEvents.RunWhen(() => WorldObjectManager.AllObjectsReady, () =>
			{
				if (AttachedObject._trackedObjects != null && AttachedObject._trackedObjects.Any(x => x.CompareTag(CompareTag)))
				{
					((IQSBTrigger)this).SendMessage(new TriggerMessage(true));
				}
			});
		}

		public override void OnRemoval()
		{
			AttachedObject.OnEntry -= OnEnterEvent;
			AttachedObject.OnExit -= OnExitEvent;

			QSBPlayerManager.OnRemovePlayer -= OnPlayerLeave;
		}

		protected void OnEnterEvent(GameObject hitObj)
		{
			if (hitObj.CompareTag(CompareTag))
			{
				((IQSBTrigger)this).SendMessage(new TriggerMessage(true));
			}
		}

		protected void OnExitEvent(GameObject hitObj)
		{
			if (hitObj.CompareTag(CompareTag))
			{
				((IQSBTrigger)this).SendMessage(new TriggerMessage(false));
			}
		}

		private void OnPlayerLeave(PlayerInfo player)
		{
			if (Occupants.Contains(player))
			{
				Exit(player);
			}
		}

		public void Enter(PlayerInfo player)
		{
			if (!Occupants.SafeAdd(player))
			{
				return;
			}

			OnEnter(player);
		}

		public void Exit(PlayerInfo player)
		{
			if (!Occupants.QuickRemove(player))
			{
				return;
			}

			OnExit(player);
		}

		/// <summary>
		/// called when a player enters this trigger
		/// </summary>
		protected virtual void OnEnter(PlayerInfo player) { }

		/// <summary>
		/// called when a player exits this trigger or leaves the game
		/// </summary>
		protected virtual void OnExit(PlayerInfo player) { }
	}
}