OnEntityTakeDamage

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

namespace Oxide.Plugins
{
    [Info("Explosive Building Damage", "RustPluginGenerator", "1.0.0")]
    [Description("Scales explosion damage taken by buildings and deployables.")]
    public class ExplosiveBuildingDamage : RustPlugin
    {
        private PluginConfig config;

        private class PluginConfig
        {
            [JsonProperty("Explosion damage multiplier")]
            public float Multiplier = 0.5f;
        }

        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();
            }
            if (config.Multiplier < 0f) config.Multiplier = 0f;
            SaveConfig();
        }

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

        protected override void LoadDefaultMessages()
        {
            lang.RegisterMessages(new Dictionary<string, string>
            {
                ["Reloaded"] = "Explosive damage multiplier is now {0}."
            }, this);
        }

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

        private void Init()
        {
            Puts("ExplosiveBuildingDamage loaded with multiplier " + config.Multiplier);
        }

        private object OnEntityTakeDamage(BaseCombatEntity entity, HitInfo hitInfo)
        {
            if (entity == null || hitInfo == null || hitInfo.damageTypes == null) return null;
            if (entity is BasePlayer) return null;

            bool isBuilding = entity is BuildingBlock;
            bool isOwned = entity.OwnerID != 0 && entity.GetBuildingPrivilege() != null;
            if (!isBuilding && !isOwned) return null;

            if (hitInfo.damageTypes.GetMajorityDamageType() != DamageType.Explosion) return null;

            hitInfo.damageTypes.Scale(DamageType.Explosion, config.Multiplier);
            return null;
        }
    }
}