OnCargoShipEgress

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

namespace Oxide.Plugins
{
    [Info("Cargo Ship Departure Alert", "RustPluginGenerator", "1.0.0")]
    [Description("Warns nearby players and optionally broadcasts when a cargo ship begins its egress.")]
    public class CargoShipDepartureAlert : RustPlugin
    {
        private const string PermUse = "cargoshipdeparturealert.use";

        private PluginConfig config;

        public class PluginConfig
        {
            [JsonProperty("Warning radius (meters)")]
            public float WarningRadius { get; set; } = 150f;

            [JsonProperty("Broadcast server-wide departure")]
            public bool BroadcastDeparture { get; set; } = true;

            [JsonProperty("Players who enabled personal warnings")]
            public List<string> WarnedPlayers { get; set; } = new List<string>();
        }

        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>
            {
                ["Broadcast"] = "A cargo ship is departing the map. Clear the deck!",
                ["PersonalWarning"] = "The cargo ship you are on is departing. Get off the deck soon.",
                ["ToggleOn"] = "Cargo ship departure warnings are now ON.",
                ["ToggleOff"] = "Cargo ship departure warnings are now OFF.",
                ["NoPermission"] = "You do not have permission to use this command."
            }, 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(PermUse, this);
        }

        [ChatCommand("cargowarn")]
        private void CmdCargoWarn(BasePlayer player, string command, string[] args)
        {
            if (player == null) return;
            if (!permission.UserHasPermission(player.UserIDString, PermUse))
            {
                SendReply(player, Msg("NoPermission", player.UserIDString));
                return;
            }

            string id = player.UserIDString;
            if (config.WarnedPlayers.Contains(id))
            {
                config.WarnedPlayers.Remove(id);
                SendReply(player, Msg("ToggleOff", id));
            }
            else
            {
                config.WarnedPlayers.Add(id);
                SendReply(player, Msg("ToggleOn", id));
            }
            SaveConfig();
        }

        private object OnCargoShipEgress(CargoShip cargoShip)
        {
            if (cargoShip == null || cargoShip.IsDestroyed) return null;

            if (config.BroadcastDeparture)
            {
                Server.Broadcast(Msg("Broadcast"));
            }

            Vector3 shipPos = cargoShip.transform.position;
            float radiusSqr = config.WarningRadius * config.WarningRadius;

            foreach (BasePlayer player in BasePlayer.activePlayerList)
            {
                if (player == null || !player.IsConnected) continue;
                if (!config.WarnedPlayers.Contains(player.UserIDString)) continue;
                if ((player.transform.position - shipPos).sqrMagnitude > radiusSqr) continue;

                SendReply(player, Msg("PersonalWarning", player.UserIDString));
            }

            return null;
        }
    }
}