using System;
using System.Collections.Generic;
using System.Linq;
using OWML.Common;
using QSB.ClientServerStateSync;
using QSB.ClientServerStateSync.Events;
using QSB.Events;
using QSB.Player;
using QSB.Player.Events;
using QSB.Player.TransformSync;
using QSB.Utility;
using QSB.WorldSync;
using QuantumUNET;
using QuantumUNET.Components;
using QuantumUNET.Messages;

namespace QSB.Messaging
{
	public static class QSBMessageManager
	{
		#region inner workings

		private static readonly Dictionary<short, Type> _msgTypeToType = new();
		private static readonly Dictionary<Type, short> _typeToMsgType = new();

		static QSBMessageManager()
		{
			var types = typeof(QSBMessage).GetDerivedTypes().ToArray();
			for (var i = 0; i < types.Length; i++)
			{
				var msgType = (short)(QMsgType.Highest + 1 + i);
				if (msgType >= short.MaxValue)
				{
					DebugLog.ToConsole("Hey, uh, maybe don't create 32,767 events? You really should never be seeing this." +
						"If you are, something has either gone terrible wrong or QSB somehow needs more events that classes in Outer Wilds." +
						"In either case, I guess something has gone terribly wrong...", MessageType.Error);
				}

				_msgTypeToType.Add(msgType, types[i]);
				_typeToMsgType.Add(types[i], msgType);
			}
		}

		public static void Init()
		{
			foreach (var msgType in _msgTypeToType.Keys)
			{
				QNetworkServer.RegisterHandlerSafe(msgType, OnServerReceive);
				QNetworkManager.singleton.client.RegisterHandlerSafe(msgType, OnClientReceive);
			}
		}

		private static void OnServerReceive(QNetworkMessage netMsg)
		{
			var msgType = netMsg.MsgType;
			var msg = (QSBMessage)Activator.CreateInstance(_msgTypeToType[msgType]);
			netMsg.ReadMessage(msg);

			if (msg.To == uint.MaxValue)
			{
				QNetworkServer.SendToAll(msgType, msg);
			}
			else if (msg.To == 0)
			{
				OnReceive(msg);
			}
			else
			{
				var conn = QNetworkServer.connections.FirstOrDefault(x => msg.To == x.GetPlayerId());
				if (conn == null)
				{
					DebugLog.ToConsole($"SendTo unknown player! id: {msg.To}, message: {msg}", MessageType.Error);
					return;
				}
				conn.Send(msgType, msg);
			}
		}

		private static void OnClientReceive(QNetworkMessage netMsg)
		{
			var msgType = netMsg.MsgType;
			var msg = (QSBMessage)Activator.CreateInstance(_msgTypeToType[msgType]);
			netMsg.ReadMessage(msg);

			OnReceive(msg);
		}

		private static void OnReceive(QSBMessage msg)
		{
			if (PlayerTransformSync.LocalInstance == null)
			{
				DebugLog.ToConsole($"Warning - Tried to handle message {msg} before localplayer was established.", MessageType.Warning);
				return;
			}

			if (QSBPlayerManager.PlayerExists(msg.From))
			{
				var player = QSBPlayerManager.GetPlayer(msg.From);

				if (!player.IsReady
				    && player.PlayerId != QSBPlayerManager.LocalPlayerId
				    && player.State is ClientState.AliveInSolarSystem or ClientState.AliveInEye or ClientState.DeadInSolarSystem
				    && msg is not QSBEventRelay { Event: PlayerInformationEvent or PlayerReadyEvent or RequestStateResyncEvent or ServerStateEvent })
				{
					DebugLog.ToConsole($"Warning - Got message {msg} from player {msg.From}, but they were not ready. Asking for state resync, just in case.", MessageType.Warning);
					QSBEventManager.FireEvent(EventNames.QSBRequestStateResync);
				}
			}

			try
			{
				if (!msg.ShouldReceive)
				{
					return;
				}

				if (msg.From != QSBPlayerManager.LocalPlayerId)
				{
					msg.OnReceiveRemote();
				}
				else
				{
					msg.OnReceiveLocal();
				}
			}
			catch (Exception ex)
			{
				DebugLog.ToConsole($"Error - Exception handling message {msg} : {ex}", MessageType.Error);
			}
		}

		#endregion


		public static void Send<M>(this M msg)
			where M : QSBMessage, new()
		{
			if (!QSBCore.IsInMultiplayer)
			{
				DebugLog.ToConsole($"Warning - Tried to send message {msg} while not connected to/hosting server.", MessageType.Warning);
				return;
			}

			msg.From = QSBPlayerManager.LocalPlayerId;
			var msgType = _typeToMsgType[typeof(M)];
			QNetworkManager.singleton.client.Send(msgType, msg);
		}

		public static void SendMessage<T, M>(this T worldObject, M msg)
			where T : IWorldObject
			where M : QSBWorldObjectMessage<T>, new()
		{
			msg.ObjectId = worldObject.ObjectId;
			Send(msg);
		}
	}
}