OnEntityLeave

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

namespace Oxide.Plugins
{
    [Info("Comfort Zone Exit", "RustPluginGenerator", "1.0.0")]
    [Description("Notifies players when they leave a comfort zone and reports how long they stayed inside")]
    public class ComfortZoneExit : RustPlugin
    {
        private const string PermNotify = "comfortzoneexit.notify";

        private PluginConfig config;
        private readonly Dictionary<ulong, float> enteredAt = new Dictionary<ulong, float>();

        private class PluginConfig
        {
            [JsonProperty("Send chat message on leave")]
            public bool Announce { get; set; } = true;

            [JsonProperty("Minimum seconds inside before announcing")]
            public float MinimumSeconds { get; set; } = 2f;
        }

        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>
            {
                ["LeftComfort"] = "You left the comfort zone after {0} seconds inside.",
                ["LeftComfortNoTime"] = "You left the comfort zone."
            }, this);
        }

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

        private void Init()
        {
            permission.RegisterPermission(PermNotify, this);
        }

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

        private object OnEntityEnter(TriggerComfort comfort, BaseEntity ent)
        {
            var player = ent as BasePlayer;
            if (player == null || player.IsNpc) return null;

            enteredAt[player.userID.Get()] = UnityEngine.Time.realtimeSinceStartup;
            return null;
        }

        private object OnEntityLeave(TriggerComfort comfort, BaseEntity ent)
        {
            var player = ent as BasePlayer;
            if (player == null || player.IsNpc) return null;

            ulong id = player.userID.Get();
            float started;
            if (!enteredAt.TryGetValue(id, out started)) return null;
            enteredAt.Remove(id);

            if (!config.Announce || !player.IsConnected) return null;
            if (!permission.UserHasPermission(player.UserIDString, PermNotify)) return null;

            float stayed = UnityEngine.Time.realtimeSinceStartup - started;
            if (stayed < config.MinimumSeconds) return null;

            player.ChatMessage(Msg("LeftComfort", player.UserIDString, Mathf.RoundToInt(stayed)));
            return null;
        }
    }
}