How to make a Rust death cause stats plugin (Oxide/Carbon)

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

namespace Oxide.Plugins
{
    [Info("Death Cause Stats", "RustPluginGenerator", "1.0.0")]
    [Description("Records each player's deaths per cause and shows the breakdown on demand.")]
    public class DeathCauseStats : RustPlugin
    {
        private const string PermAdmin = "deathcausestats.admin";

        private PluginConfig config;
        private StoredData data;
        private Timer saveTimer;

        private class PluginConfig
        {
            [JsonProperty("Save interval in seconds")]
            public int SaveIntervalSeconds = 300;

            [JsonProperty("Broadcast deaths to all players")]
            public bool BroadcastDeaths = false;

            [JsonProperty("Max causes shown in chat")]
            public int MaxCausesShown = 8;
        }

        private class StoredData
        {
            [JsonProperty("Players")]
            public Dictionary<string, Dictionary<string, int>> Players = new Dictionary<string, Dictionary<string, int>>();
        }

        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>
            {
                ["Header"] = "<color=#ce9e39>Death breakdown for {0}</color>",
                ["Footer"] = "Total deaths: {0}",
                ["Line"] = "{0}: {1}",
                ["Truncated"] = "and {0} more cause(s) not shown",
                ["NoDeaths"] = "{0} has not died yet.",
                ["Self"] = "You",
                ["Broadcast"] = "{0} died ({1}).",
                ["Invalid"] = "That player could not be found.",
                ["Denied"] = "You do not have permission to look up other players.",
                ["Cause.player"] = "Killed by player",
                ["Cause.npc"] = "Killed by NPC/turret",
                ["Cause.animal"] = "Killed by animal",
                ["Cause.self"] = "Suicide",
                ["Cause.fall"] = "Fall damage",
                ["Cause.drown"] = "Drowning",
                ["Cause.cold"] = "Cold",
                ["Cause.radiation"] = "Radiation",
                ["Cause.bleed"] = "Bleeding out",
                ["Cause.explosion"] = "Explosion",
                ["Cause.decay"] = "Decay",
                ["Cause.other"] = "Other"
            }, 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 OnServerInitialized()
        {
            data = Interface.Oxide.DataFileSystem.ReadObject<StoredData>(Name) ?? new StoredData();
            saveTimer = timer.Every(Math.Max(30, config.SaveIntervalSeconds), SaveData);
        }

        private void Unload()
        {
            if (saveTimer != null)
            {
                saveTimer.Destroy();
                saveTimer = null;
            }
            SaveData();
        }

        private void SaveData()
        {
            if (data != null)
                Interface.Oxide.DataFileSystem.WriteObject(Name, data);
        }

        private object OnPlayerDeath(BasePlayer player, HitInfo info)
        {
            if (player == null || data == null || player.IsNpc)
                return null;

            string cause = Classify(player, info);
            string id = player.UserIDString;

            Dictionary<string, int> causes;
            if (!data.Players.TryGetValue(id, out causes))
            {
                causes = new Dictionary<string, int>();
                data.Players[id] = causes;
            }

            int current;
            causes.TryGetValue(cause, out current);
            causes[cause] = current + 1;

            if (config.BroadcastDeaths)
                Server.Broadcast(Msg("Broadcast", null, player.displayName, Msg("Cause." + cause)));

            return null;
        }

        private string Classify(BasePlayer victim, HitInfo info)
        {
            if (info == null)
                return "self";

            BasePlayer attacker = info.InitiatorPlayer;
            if (attacker != null && !attacker.IsNpc)
                return attacker == victim ? "self" : "player";

            BaseEntity initiator = info.Initiator;
            if (initiator != null)
            {
                if (initiator == victim)
                    return "self";
                if (initiator is BaseAnimalNPC)
                    return "animal";
                if (initiator is ScientistNPC || initiator is BradleyAPC || initiator is BaseHelicopter)
                    return "npc";
            }

            Rust.DamageType type = info.damageTypes.GetMajorityDamageType();
            switch (type)
            {
                case Rust.DamageType.Fall: return "fall";
                case Rust.DamageType.Cold: return "cold";
                case Rust.DamageType.Radiation: return "radiation";
                case Rust.DamageType.Bleeding: return "bleed";
                case Rust.DamageType.Explosion: return "explosion";
                case Rust.DamageType.Decay: return "decay";
                case Rust.DamageType.Suicide: return "self";
                case Rust.DamageType.Bullet: return attacker != null ? "npc" : "other";
                default: return "other";
            }
        }

        [ChatCommand("deaths")]
        private void CmdDeaths(BasePlayer player, string command, string[] args)
        {
            if (player == null)
                return;

            string targetId = player.UserIDString;
            string targetName = player.displayName;
            bool isSelf = true;

            if (args != null && args.Length > 0)
            {
                if (!permission.UserHasPermission(player.UserIDString, PermAdmin))
                {
                    SendReply(player, Msg("Denied", player.UserIDString));
                    return;
                }

                BasePlayer target = BasePlayer.FindAwakeOrSleeping(args[0]);
                if (target == null)
                {
                    SendReply(player, Msg("Invalid", player.UserIDString));
                    return;
                }

                targetId = target.UserIDString;
                targetName = target.displayName;
                isSelf = target == player;
            }

            Dictionary<string, int> causes;
            if (!data.Players.TryGetValue(targetId, out causes) || causes.Count == 0)
            {
                SendReply(player, Msg("NoDeaths", player.UserIDString, isSelf ? Msg("Self", player.UserIDString) : targetName));
                return;
            }

            SendReply(player, Msg("Header", player.UserIDString, targetName));

            int total = causes.Values.Sum();
            var ordered = causes.OrderByDescending(kv => kv.Value).ToList();
            int shown = 0;

            foreach (var entry in ordered)
            {
                if (shown >= config.MaxCausesShown)
                    break;
                SendReply(player, Msg("Line", player.UserIDString, Msg("Cause." + entry.Key), entry.Value));
                shown++;
            }

            if (ordered.Count > shown)
                SendReply(player, Msg("Truncated", player.UserIDString, ordered.Count - shown));

            SendReply(player, Msg("Footer", player.UserIDString, total));
        }
    }
}