OnMapMarkersClear

using System;
using System.Collections.Generic;
using Newtonsoft.Json;
using Oxide.Core;
using ProtoBuf;
using UnityEngine;

namespace Oxide.Plugins
{
    [Info("Map Marker Guard", "RustPluginGenerator", "1.0.0")]
    [Description("Restores a player's map markers when the clear routine fires.")]
    public class MapMarkerGuard : RustPlugin
    {
        private PluginConfig config;
        private readonly Dictionary<ulong, List<ProtoBuf.MapNote>> savedMarkers = new Dictionary<ulong, List<ProtoBuf.MapNote>>();

        private class PluginConfig
        {
            [JsonProperty("Protect markers on clear")]
            public bool Protect { get; set; } = true;
        }

        protected override void LoadDefaultConfig() => config = new PluginConfig();

        protected override void LoadConfig()
        {
            base.LoadConfig();
            try
            {
                config = Config.ReadObject<PluginConfig>();
                if (config == null) throw new Exception();
            }
            catch
            {
                PrintWarning("Configuration file is invalid, using defaults");
                LoadDefaultConfig();
            }
            SaveConfig();
        }

        protected override void SaveConfig() => Config.WriteObject(config);

        protected override void LoadDefaultMessages()
        {
            lang.RegisterMessages(new Dictionary<string, string>
            {
                ["MarkersRestored"] = "Your map markers have been restored.",
                ["MarkersCleared"] = "Map marker clearing is disabled on this server."
            }, this);
        }

        private string Msg(string key, string userId = null, params object[] args) => string.Format(lang.GetMessage(key, this, userId), args);

        private object OnMapMarkersClear(BasePlayer player, List<ProtoBuf.MapNote> pointsOfInterest)
        {
            if (!config.Protect || player == null) return null;

            if (pointsOfInterest != null && pointsOfInterest.Count > 0)
                savedMarkers[player.userID.Get()] = new List<ProtoBuf.MapNote>(pointsOfInterest);

            NextTick(() =>
            {
                if (player == null || !player.IsConnected) return;
                List<ProtoBuf.MapNote> notes;
                if (!savedMarkers.TryGetValue(player.userID.Get(), out notes) || notes.Count == 0) return;
                player.SendConsoleCommand("gametip.showtoast", Msg("MarkersRestored", player.UserIDString));
            });

            return true;
        }

        private object OnMapMarkerAdded(BasePlayer player, ProtoBuf.MapNote note)
        {
            if (player == null || note == null) return null;
            List<ProtoBuf.MapNote> notes;
            if (!savedMarkers.TryGetValue(player.userID.Get(), out notes))
            {
                notes = new List<ProtoBuf.MapNote>();
                savedMarkers[player.userID.Get()] = notes;
            }
            notes.Add(note);
            return null;
        }

        private void OnPlayerDisconnected(BasePlayer player, string reason)
        {
            if (player == null) return;
            savedMarkers.Remove(player.userID.Get());
        }

        private void Unload()
        {
            savedMarkers.Clear();
        }
    }
}