BepInEx/BepInEx.Preloader/UnityPatches.cs

using System;
using System.Collections.Generic;
using System.Reflection;
using BepInEx.Harmony;
using Harmony;

namespace BepInEx.Preloader
{
    internal static class UnityPatches
    {
        public static HarmonyInstance HarmonyInstance { get; } = HarmonyInstance.Create("com.bepinex.unitypatches");

        public static Dictionary<string, string> AssemblyLocations { get; } =
            new Dictionary<string, string>(StringComparer.InvariantCultureIgnoreCase);

        public static void Apply()
        {
            HarmonyWrapper.PatchAll(typeof(UnityPatches), HarmonyInstance);
        }

        [HarmonyPostfix]
        [HarmonyPatch(typeof(Assembly), nameof(Assembly.Location), MethodType.Getter)]
        public static void GetLocation(ref string __result, Assembly __instance)
        {
            if (AssemblyLocations.TryGetValue(__instance.FullName, out string location))
                __result = location;
        }

        [HarmonyPostfix]
        [HarmonyPatch(typeof(Assembly), nameof(Assembly.CodeBase), MethodType.Getter)]
        public static void GetCodeBase(ref string __result, Assembly __instance)
        {
            if (AssemblyLocations.TryGetValue(__instance.FullName, out string location))
                __result = $"file://{location.Replace('\\', '/')}";
        }

#if UNITY_2018
/*
 * DESC: Workaround for Trace class not working because of missing .config file
 * AFFECTS: Unity 2018+
 */
        [HarmonyPostfix, HarmonyPatch(typeof(AppDomain), nameof(AppDomain.SetupInformation), MethodType.Getter)]
        public static void GetExeConfigName(AppDomainSetup __result)
        {
            __result.ApplicationBase = $"file://{Paths.GameRootPath}";
            __result.ConfigurationFile = "app.config";
        }
#endif
    }
}