How to make a Rust fishing bonus plugin (catch multipliers)

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

namespace Oxide.Plugins
{
    [Info("Fishing Bonus", "RustPluginGenerator", "1.0.0")]
    [Description("Multiplies caught fish amounts and rolls a weighted bonus item table after every catch.")]
    public class FishingBonus : RustPlugin
    {
        private const string PermAdmin = "fishingbonus.admin";

        private PluginConfig config;

        private class PluginConfig
        {
            [JsonProperty("Catch multiplier")]
            public float CatchMultiplier = 2f;

            [JsonProperty("Bonus chance (0-1)")]
            public float BonusChance = 0.25f;

            [JsonProperty("Bonus items")]
            public List<BonusEntry> BonusItems = new List<BonusEntry>
            {
                new BonusEntry { Shortname = "scrap", MinAmount = 2, MaxAmount = 8, Weight = 5 },
                new BonusEntry { Shortname = "seed.hemp", MinAmount = 1, MaxAmount = 3, Weight = 3 },
                new BonusEntry { Shortname = "wolfmeat.raw", MinAmount = 1, MaxAmount = 2, Weight = 1 }
            };
        }

        private class BonusEntry
        {
            [JsonProperty("Item shortname")]
            public string Shortname = "scrap";

            [JsonProperty("Minimum amount")]
            public int MinAmount = 1;

            [JsonProperty("Maximum amount")]
            public int MaxAmount = 1;

            [JsonProperty("Weight")]
            public float Weight = 1f;
        }

        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>
            {
                ["NotPermitted"] = "You do not have permission to use this command.",
                ["Settings"] = "Fishing bonus: multiplier x{0}, bonus chance {1}%. Bonus entries: {2}.",
                ["Reloaded"] = "Configuration reloaded."
            }, 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(PermAdmin, this);
        }

        private void OnFishCaught(ItemDefinition currentFishTarget, BaseFishingRod fishingRod, BasePlayer ownerPlayer)
        {
            if (currentFishTarget == null || fishingRod == null || ownerPlayer == null) return;
            if (ownerPlayer.IsNpc || !ownerPlayer.IsConnected) return;

            ApplyExtraFish(currentFishTarget, ownerPlayer);

            if (UnityEngine.Random.Range(0f, 1f) < Mathf.Clamp01(config.BonusChance))
            {
                GiveBonusItem(ownerPlayer);
            }
        }

        private void ApplyExtraFish(ItemDefinition fish, BasePlayer player)
        {
            int extra = Mathf.FloorToInt(Mathf.Clamp(config.CatchMultiplier, 0f, 20f));
            if (extra <= 0) return;

            int amount = Mathf.Min(extra, fish.stackable > 0 ? fish.stackable : extra);
            for (int i = 0; i < extra; i++)
            {
                Item item = ItemManager.CreateByName(fish.shortname, amount, 0);
                if (item == null) return;
                player.GiveItem(item);
            }
        }

        private void GiveBonusItem(BasePlayer player)
        {
            if (config.BonusItems == null || config.BonusItems.Count == 0) return;

            float total = 0f;
            foreach (BonusEntry entry in config.BonusItems)
            {
                if (entry == null || entry.Weight <= 0f) continue;
                total += entry.Weight;
            }
            if (total <= 0f) return;

            float roll = UnityEngine.Random.Range(0f, total);
            BonusEntry chosen = null;
            foreach (BonusEntry entry in config.BonusItems)
            {
                if (entry == null || entry.Weight <= 0f) continue;
                roll -= entry.Weight;
                if (roll <= 0f)
                {
                    chosen = entry;
                    break;
                }
            }
            if (chosen == null) return;

            ItemDefinition def = ItemManager.FindItemDefinition(chosen.Shortname);
            if (def == null) return;

            int min = Mathf.Max(1, chosen.MinAmount);
            int max = Mathf.Max(1, chosen.MaxAmount);
            if (min > max)
            {
                int swap = min;
                min = max;
                max = swap;
            }

            int amount = UnityEngine.Random.Range(min, max + 1);
            Item bonus = ItemManager.CreateByItemID(def.itemid, amount, 0);
            if (bonus == null) return;

            player.GiveItem(bonus);
        }

        [ChatCommand("fishbonus")]
        private void CmdFishBonus(BasePlayer player, string command, string[] args)
        {
            if (player == null) return;
            if (!permission.UserHasPermission(player.UserIDString, PermAdmin))
            {
                player.ChatMessage(Msg("NotPermitted", player.UserIDString));
                return;
            }

            LoadConfig();
            player.ChatMessage(Msg("Settings", player.UserIDString, config.CatchMultiplier,
                Mathf.RoundToInt(config.BonusChance * 100f), config.BonusItems?.Count ?? 0));
            player.ChatMessage(Msg("Reloaded", player.UserIDString));
        }

        private void Unload()
        {
        }
    }
}