UndeadUniversalPatch/Core/BuildSettings.cs

// Undead Universal Patch - for patching Rec Room builds
// Copyright (C) 2026 proxnet.dev (@zombieb)
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY

using HarmonyLib;
using System;
using System.Linq;
using System.Reflection;
using UndeadUniversalPatch.Core.Exceptions;

namespace UndeadUniversalPatch.Core;

internal static class BuildSettings
{
    public static Assembly GetAssemblyCSharp()
    {
        if (!Init.GetIsRecRoom())
            throw new NotRecRoomException();

        return AccessTools.TypeByName("BootSequence").Assembly; // always unobfuscated
    }

    private static Type GetBuildSettings()
    {
        var assembly = GetAssemblyCSharp();

        try
        {
            Type type = assembly.GetTypes().First(type => Symbols.BuildSettings.Contains(type.Name));
            return type;
        } catch (ReflectionTypeLoadException ex)
        {
            Type type = ex.Types.First(type => Symbols.BuildSettings.Contains(type.Name));
            return type;
        } catch
        {
            return null;
        }
    }

    public static string GetVersion()
    {
        var unknown = "Unknown Version";

        var buildSettings = GetBuildSettings();
        if (buildSettings == null)
#if NET35
        {
            try
            {
                // doesn't exist? -> error will be caught & unknown will be returned
                var field = AccessTools.Field("PUNNetworkManager:BUILD_VERSION");

                if (field != null) return (string)field.GetValue(null);
                else return "Unknown Legacy Version";
            } catch
            {
                return unknown;
            }
        }
#else
          return unknown;
#endif

        Func<string, bool> check = (string value) =>
        {
            if (value == null) return false;
            return value.StartsWith("20") || value.EndsWith("_EA");
        };

        try
        {
#if NET6_0
            return (string)buildSettings.GetRuntimeProperties().Where(prop => prop.PropertyType == typeof(string)).First(prop =>
            {
                var value = (string)prop.GetValue(null);
                return check(value);
            }).GetValue(null);
#else
            return (string)buildSettings.GetFields().Where(field => field.FieldType == typeof(string)).First(field =>
            {
                var value = (string)field.GetValue(null);
                return check(value);
            }).GetValue(null);
#endif
        }
        catch
        {
            return unknown;
        }
    }

    public static string GetBuildTimestamp()
    {
        var unknown = "Unknown Timestamp";

        var buildSettings = GetBuildSettings();
        if (buildSettings == null) return unknown;

        // Only one `long` exists on BuildSettings across all supported builds
        try
        {
#if NET6_0
            var foundProp = buildSettings.GetRuntimeProperties()
                .First(prop => prop.PropertyType == typeof(long));

            var value = (long)foundProp.GetValue(null);
            return new DateTime(value).ToString();
#else
            var foundField = buildSettings.GetFields()
                .First(field => field.FieldType == typeof(long));

            var value = (long)foundField.GetValue(null);
            return new DateTime(value).ToString();
#endif
        }
        catch
        {
            return unknown;
        }
    }

    private static class Symbols
    {
        // type list compiled by @zombieb
        public static string[] BuildSettings = [
            "BuildSettings",
            "BBHENFCNLAB",
            "KMJJGELKNAP",
            "FJEEPOKGDNG",
            "LACHJMJGMPK",
            "NNBKABHFGFB",
            "KMGJBIHAAJL",
            "FALNDOJFPMN",
            "IODMKGDNMID",
            "HIPJBMLBLHH",
            "LEADBBLICBL",
            "NPPACKKFLIK",
            "MOFAAFLMFJO",
            "EMIDOAHOJNO",
            "IKJNDDBHIAC",
            "OOCIKEIJMCA",
            "HPFCOJFIIKK",
            "MONBJIBCJFA",
            "GFDKEKGOMCP",
            "MIMHAGFDGND",
            "LFJMHJPHKOK",
            "NOHBMMJBMIP",
            "GJBEJNGDEJM",
            "OGBGLFJGKJL",
            "PEJOGOOEOKE",
            "FDKFNHNNDEE",
            "EDNIOJBEKLL",
            "FEKFIFPGDDP",
            "POOFEABAPOB",
            "JHFKADKFKPD",
            "GGKABOEOKMI",
            "FAPDBIGGJHM",
            "EPKEIOCFFMO",
            "ECLPNEHKLEP",
            "BGMDPOMLCKD",
            "IMJIAGILBOG",
            "OGGKBKOBHLP",
            "DMAKDOEIOFE",
            "HHGCEDNGMDD",
            "OFDPCKGMCFG",
            "FPABNHKCIDD",
            "NEOOKMCECAL",
            "CKEBMNKBEAH",
            "IBPMLICGIOI",
            "LMJOEPJHBLC",
            "HJINOEPLIMF",
            "JMHFJIBKCMG",
            "HJKAEMGCIGB",
            "BNOEINBHPIG",
            "AJJAIFIKCJP",
            "FCPHGJMAGPI",
            "DDCENHLJGNM",
            "AEPEEKCCDJL",
            "IDDIAODMAPP",
            "CHIMGKLHFMK",
            "OGDOAJJPBOC",
            "EMABNNHNJIB",
            "JNEAMPKAHFM",
            "FPGILFHDJNI",
            "MDPMNBEPOKF",
            "FNKGHFILBEE",
            "AEOMDHAKPGC",
            "OGEBJBBMDEO",
            "CJMCNIDOMCP",
            "LCCKMCOLKFI",
            "DEIHAEKLPDJ",
            "LENMMNLPJOL",
            "JKNIDJECBFD",
            "FMEMABGECKK",
            "HAOBGEPJMAN",
            "FDCGGKFBOPN",
            "OKCPMCEGCOK",
            "BNKCNOFCGDK"
        ];
    }
}