Folder restructuring from primedev (#624)v1.21.2-rc3v1.21.2

Copies of over the primedev folder structure for easier cherry-picking of further changes

Co-authored-by: F1F7Y <filip.bartos07@proton.me>

10 files changed, 3047 insertions, 0 deletions

diff --git a/primedev/mods/autodownload/moddownloader.cpp b/primedev/mods/autodownload/moddownloader.cpp
new file mode 100644
index 00000000..165399e3
--- /dev/null
+++ b/primedev/mods/autodownload/moddownloader.cpp
@@ -0,0 +1,638 @@
+#include "moddownloader.h"
+#include <rapidjson/fwd.h>
+#include <mz_strm_mem.h>
+#include <mz.h>
+#include <mz_strm.h>
+#include <mz_zip.h>
+#include <mz_compat.h>
+#include <thread>
+#include <future>
+#include <bcrypt.h>
+#include <winternl.h>
+#include <fstream>
+
+ModDownloader* g_pModDownloader;
+
+ModDownloader::ModDownloader()
+{
+	spdlog::info("Mod downloader initialized");
+
+	// Initialise mods list URI
+	char* clachar = strstr(GetCommandLineA(), CUSTOM_MODS_URL_FLAG);
+	if (clachar)
+	{
+		std::string url;
+		int iFlagStringLength = strlen(CUSTOM_MODS_URL_FLAG);
+		std::string cla = std::string(clachar);
+		if (strncmp(cla.substr(iFlagStringLength, 1).c_str(), "\"", 1))
+		{
+			int space = cla.find(" ");
+			url = cla.substr(iFlagStringLength, space - iFlagStringLength);
+		}
+		else
+		{
+			std::string quote = "\"";
+			int quote1 = cla.find(quote);
+			int quote2 = (cla.substr(quote1 + 1)).find(quote);
+			url = cla.substr(quote1 + 1, quote2);
+		}
+		spdlog::info("Found custom verified mods URL in command line argument: {}", url);
+		modsListUrl = strdup(url.c_str());
+	}
+	else
+	{
+		spdlog::info("Custom verified mods URL not found in command line arguments, using default URL.");
+		modsListUrl = strdup(DEFAULT_MODS_LIST_URL);
+	}
+}
+
+size_t WriteToString(void* ptr, size_t size, size_t count, void* stream)
+{
+	((std::string*)stream)->append((char*)ptr, 0, size * count);
+	return size * count;
+}
+
+void ModDownloader::FetchModsListFromAPI()
+{
+	std::thread requestThread(
+		[this]()
+		{
+			CURLcode result;
+			CURL* easyhandle;
+			rapidjson::Document verifiedModsJson;
+			std::string url = modsListUrl;
+
+			curl_global_init(CURL_GLOBAL_ALL);
+			easyhandle = curl_easy_init();
+			std::string readBuffer;
+
+			// Fetching mods list from GitHub repository
+			curl_easy_setopt(easyhandle, CURLOPT_CUSTOMREQUEST, "GET");
+			curl_easy_setopt(easyhandle, CURLOPT_TIMEOUT, 30L);
+			curl_easy_setopt(easyhandle, CURLOPT_URL, url.c_str());
+			curl_easy_setopt(easyhandle, CURLOPT_FAILONERROR, 1L);
+			curl_easy_setopt(easyhandle, CURLOPT_WRITEDATA, &readBuffer);
+			curl_easy_setopt(easyhandle, CURLOPT_WRITEFUNCTION, WriteToString);
+			result = curl_easy_perform(easyhandle);
+
+			if (result == CURLcode::CURLE_OK)
+			{
+				spdlog::info("Mods list successfully fetched.");
+			}
+			else
+			{
+				spdlog::error("Fetching mods list failed: {}", curl_easy_strerror(result));
+				goto REQUEST_END_CLEANUP;
+			}
+
+			// Load mods list into local state
+			spdlog::info("Loading mods configuration...");
+			verifiedModsJson.Parse(readBuffer);
+			for (auto i = verifiedModsJson.MemberBegin(); i != verifiedModsJson.MemberEnd(); ++i)
+			{
+				std::string name = i->name.GetString();
+				std::string dependency = i->value["DependencyPrefix"].GetString();
+
+				std::unordered_map<std::string, VerifiedModVersion> modVersions;
+				rapidjson::Value& versions = i->value["Versions"];
+				assert(versions.IsArray());
+				for (auto& attribute : versions.GetArray())
+				{
+					assert(attribute.IsObject());
+					std::string version = attribute["Version"].GetString();
+					std::string checksum = attribute["Checksum"].GetString();
+					modVersions.insert({version, {.checksum = checksum}});
+				}
+
+				VerifiedModDetails modConfig = {.dependencyPrefix = dependency, .versions = modVersions};
+				verifiedMods.insert({name, modConfig});
+				spdlog::info("==> Loaded configuration for mod \"" + name + "\"");
+			}
+
+			spdlog::info("Done loading verified mods list.");
+
+		REQUEST_END_CLEANUP:
+			curl_easy_cleanup(easyhandle);
+		});
+	requestThread.detach();
+}
+
+size_t WriteData(void* ptr, size_t size, size_t nmemb, FILE* stream)
+{
+	size_t written;
+	written = fwrite(ptr, size, nmemb, stream);
+	return written;
+}
+
+int ModDownloader::ModFetchingProgressCallback(
+	void* ptr, curl_off_t totalDownloadSize, curl_off_t finishedDownloadSize, curl_off_t totalToUpload, curl_off_t nowUploaded)
+{
+	if (totalDownloadSize != 0 && finishedDownloadSize != 0)
+	{
+		ModDownloader* instance = static_cast<ModDownloader*>(ptr);
+		auto currentDownloadProgress = roundf(static_cast<float>(finishedDownloadSize) / totalDownloadSize * 100);
+		instance->modState.progress = finishedDownloadSize;
+		instance->modState.total = totalDownloadSize;
+		instance->modState.ratio = currentDownloadProgress;
+	}
+
+	return 0;
+}
+
+std::optional<fs::path> ModDownloader::FetchModFromDistantStore(std::string_view modName, std::string_view modVersion)
+{
+	// Retrieve mod prefix from local mods list, or use mod name as mod prefix if bypass flag is set
+	std::string modPrefix = strstr(GetCommandLineA(), VERIFICATION_FLAG) ? modName.data() : verifiedMods[modName.data()].dependencyPrefix;
+	// Build archive distant URI
+	std::string archiveName = std::format("{}-{}.zip", modPrefix, modVersion.data());
+	std::string url = STORE_URL + archiveName;
+	spdlog::info(std::format("Fetching mod archive from {}", url));
+
+	// Download destination
+	std::filesystem::path downloadPath = std::filesystem::temp_directory_path() / archiveName;
+	spdlog::info(std::format("Downloading archive to {}", downloadPath.generic_string()));
+
+	// Update state
+	modState.state = DOWNLOADING;
+
+	// Download the actual archive
+	bool failed = false;
+	FILE* fp = fopen(downloadPath.generic_string().c_str(), "wb");
+	CURLcode result;
+	CURL* easyhandle;
+	easyhandle = curl_easy_init();
+
+	curl_easy_setopt(easyhandle, CURLOPT_URL, url.data());
+	curl_easy_setopt(easyhandle, CURLOPT_FAILONERROR, 1L);
+	curl_easy_setopt(easyhandle, CURLOPT_WRITEDATA, fp);
+	curl_easy_setopt(easyhandle, CURLOPT_WRITEFUNCTION, WriteData);
+	curl_easy_setopt(easyhandle, CURLOPT_NOPROGRESS, 0L);
+	curl_easy_setopt(easyhandle, CURLOPT_XFERINFOFUNCTION, ModDownloader::ModFetchingProgressCallback);
+	curl_easy_setopt(easyhandle, CURLOPT_XFERINFODATA, this);
+	result = curl_easy_perform(easyhandle);
+
+	if (result == CURLcode::CURLE_OK)
+	{
+		spdlog::info("Mod archive successfully fetched.");
+		goto REQUEST_END_CLEANUP;
+	}
+	else
+	{
+		spdlog::error("Fetching mod archive failed: {}", curl_easy_strerror(result));
+		failed = true;
+		goto REQUEST_END_CLEANUP;
+	}
+
+REQUEST_END_CLEANUP:
+	curl_easy_cleanup(easyhandle);
+	fclose(fp);
+	return failed ? std::optional<fs::path>() : std::optional<fs::path>(downloadPath);
+}
+
+bool ModDownloader::IsModLegit(fs::path modPath, std::string_view expectedChecksum)
+{
+	if (strstr(GetCommandLineA(), VERIFICATION_FLAG))
+	{
+		spdlog::info("Bypassing mod verification due to flag set up.");
+		return true;
+	}
+
+	// Update state
+	modState.state = CHECKSUMING;
+
+	NTSTATUS status;
+	BCRYPT_ALG_HANDLE algorithmHandle = NULL;
+	BCRYPT_HASH_HANDLE hashHandle = NULL;
+	std::vector<uint8_t> hash;
+	DWORD hashLength = 0;
+	DWORD resultLength = 0;
+	std::stringstream ss;
+
+	constexpr size_t bufferSize {1 << 12};
+	std::vector<char> buffer(bufferSize, '\0');
+	std::ifstream fp(modPath.generic_string(), std::ios::binary);
+
+	// Open an algorithm handle
+	// This sample passes BCRYPT_HASH_REUSABLE_FLAG with BCryptAlgorithmProvider(...) to load a provider which supports reusable hash
+	status = BCryptOpenAlgorithmProvider(
+		&algorithmHandle, // Alg Handle pointer
+		BCRYPT_SHA256_ALGORITHM, // Cryptographic Algorithm name (null terminated unicode string)
+		NULL, // Provider name; if null, the default provider is loaded
+		BCRYPT_HASH_REUSABLE_FLAG); // Flags; Loads a provider which supports reusable hash
+	if (!NT_SUCCESS(status))
+	{
+		modState.state = MOD_CORRUPTED;
+		goto cleanup;
+	}
+
+	// Obtain the length of the hash
+	status = BCryptGetProperty(
+		algorithmHandle, // Handle to a CNG object
+		BCRYPT_HASH_LENGTH, // Property name (null terminated unicode string)
+		(PBYTE)&hashLength, // Address of the output buffer which recieves the property value
+		sizeof(hashLength), // Size of the buffer in bytes
+		&resultLength, // Number of bytes that were copied into the buffer
+		0); // Flags
+	if (!NT_SUCCESS(status))
+	{
+		// goto cleanup;
+		modState.state = MOD_CORRUPTED;
+		return false;
+	}
+
+	// Create a hash handle
+	status = BCryptCreateHash(
+		algorithmHandle, // Handle to an algorithm provider
+		&hashHandle, // A pointer to a hash handle - can be a hash or hmac object
+		NULL, // Pointer to the buffer that recieves the hash/hmac object
+		0, // Size of the buffer in bytes
+		NULL, // A pointer to a key to use for the hash or MAC
+		0, // Size of the key in bytes
+		0); // Flags
+	if (!NT_SUCCESS(status))
+	{
+		modState.state = MOD_CORRUPTED;
+		goto cleanup;
+	}
+
+	// Hash archive content
+	if (!fp.is_open())
+	{
+		spdlog::error("Unable to open archive.");
+		modState.state = FAILED_READING_ARCHIVE;
+		return false;
+	}
+	fp.seekg(0, fp.beg);
+	while (fp.good())
+	{
+		fp.read(buffer.data(), bufferSize);
+		std::streamsize bytesRead = fp.gcount();
+		if (bytesRead > 0)
+		{
+			status = BCryptHashData(hashHandle, (PBYTE)buffer.data(), bytesRead, 0);
+			if (!NT_SUCCESS(status))
+			{
+				modState.state = MOD_CORRUPTED;
+				goto cleanup;
+			}
+		}
+	}
+
+	hash = std::vector<uint8_t>(hashLength);
+
+	// Obtain the hash of the message(s) into the hash buffer
+	status = BCryptFinishHash(
+		hashHandle, // Handle to the hash or MAC object
+		hash.data(), // A pointer to a buffer that receives the hash or MAC value
+		hashLength, // Size of the buffer in bytes
+		0); // Flags
+	if (!NT_SUCCESS(status))
+	{
+		modState.state = MOD_CORRUPTED;
+		goto cleanup;
+	}
+
+	// Convert hash to string using bytes raw values
+	ss << std::hex << std::setfill('0');
+	for (int i = 0; i < hashLength; i++)
+	{
+		ss << std::hex << std::setw(2) << static_cast<int>(hash.data()[i]);
+	}
+
+	spdlog::info("Expected checksum: {}", expectedChecksum.data());
+	spdlog::info("Computed checksum: {}", ss.str());
+	return expectedChecksum.compare(ss.str()) == 0;
+
+cleanup:
+	if (NULL != hashHandle)
+	{
+		BCryptDestroyHash(hashHandle); // Handle to hash/MAC object which needs to be destroyed
+	}
+
+	if (NULL != algorithmHandle)
+	{
+		BCryptCloseAlgorithmProvider(
+			algorithmHandle, // Handle to the algorithm provider which needs to be closed
+			0); // Flags
+	}
+
+	return false;
+}
+
+bool ModDownloader::IsModAuthorized(std::string_view modName, std::string_view modVersion)
+{
+	if (strstr(GetCommandLineA(), VERIFICATION_FLAG))
+	{
+		spdlog::info("Bypassing mod verification due to flag set up.");
+		return true;
+	}
+
+	if (!verifiedMods.contains(modName.data()))
+	{
+		return false;
+	}
+
+	std::unordered_map<std::string, VerifiedModVersion> versions = verifiedMods[modName.data()].versions;
+	return versions.count(modVersion.data()) != 0;
+}
+
+int GetModArchiveSize(unzFile file, unz_global_info64 info)
+{
+	int totalSize = 0;
+
+	for (int i = 0; i < info.number_entry; i++)
+	{
+		char zipFilename[256];
+		unz_file_info64 fileInfo;
+		unzGetCurrentFileInfo64(file, &fileInfo, zipFilename, sizeof(zipFilename), NULL, 0, NULL, 0);
+
+		totalSize += fileInfo.uncompressed_size;
+
+		if ((i + 1) < info.number_entry)
+		{
+			unzGoToNextFile(file);
+		}
+	}
+
+	// Reset file pointer for archive extraction
+	unzGoToFirstFile(file);
+
+	return totalSize;
+}
+
+void ModDownloader::ExtractMod(fs::path modPath)
+{
+	unzFile file;
+	std::string name;
+	fs::path modDirectory;
+
+	file = unzOpen(modPath.generic_string().c_str());
+	if (file == NULL)
+	{
+		spdlog::error("Cannot open archive located at {}.", modPath.generic_string());
+		modState.state = FAILED_READING_ARCHIVE;
+		goto EXTRACTION_CLEANUP;
+	}
+
+	unz_global_info64 gi;
+	int status;
+	status = unzGetGlobalInfo64(file, &gi);
+	if (status != UNZ_OK)
+	{
+		spdlog::error("Failed getting information from archive (error code: {})", status);
+		modState.state = FAILED_READING_ARCHIVE;
+		goto EXTRACTION_CLEANUP;
+	}
+
+	// Update state
+	modState.state = EXTRACTING;
+	modState.total = GetModArchiveSize(file, gi);
+	modState.progress = 0;
+
+	// Mod directory name (removing the ".zip" fom the archive name)
+	name = modPath.filename().string();
+	name = name.substr(0, name.length() - 4);
+	modDirectory = GetRemoteModFolderPath() / name;
+
+	for (int i = 0; i < gi.number_entry; i++)
+	{
+		char zipFilename[256];
+		unz_file_info64 fileInfo;
+		status = unzGetCurrentFileInfo64(file, &fileInfo, zipFilename, sizeof(zipFilename), NULL, 0, NULL, 0);
+
+		// Extract file
+		{
+			std::error_code ec;
+			fs::path fileDestination = modDirectory / zipFilename;
+			spdlog::info("=> {}", fileDestination.generic_string());
+
+			// Create parent directory if needed
+			if (!std::filesystem::exists(fileDestination.parent_path()))
+			{
+				spdlog::info("Parent directory does not exist, creating it.", fileDestination.generic_string());
+				if (!std::filesystem::create_directories(fileDestination.parent_path(), ec) && ec.value() != 0)
+				{
+					spdlog::error("Parent directory ({}) creation failed.", fileDestination.parent_path().generic_string());
+					modState.state = FAILED_WRITING_TO_DISK;
+					goto EXTRACTION_CLEANUP;
+				}
+			}
+
+			// If current file is a directory, create directory...
+			if (fileDestination.generic_string().back() == '/')
+			{
+				// Create directory
+				if (!std::filesystem::create_directory(fileDestination, ec) && ec.value() != 0)
+				{
+					spdlog::error("Directory creation failed: {}", ec.message());
+					modState.state = FAILED_WRITING_TO_DISK;
+					goto EXTRACTION_CLEANUP;
+				}
+			}
+			// ...else create file
+			else
+			{
+				// Ensure file is in zip archive
+				if (unzLocateFile(file, zipFilename, 0) != UNZ_OK)
+				{
+					spdlog::error("File \"{}\" was not found in archive.", zipFilename);
+					modState.state = FAILED_READING_ARCHIVE;
+					goto EXTRACTION_CLEANUP;
+				}
+
+				// Create file
+				const int bufferSize = 8192;
+				void* buffer;
+				int err = UNZ_OK;
+				FILE* fout = NULL;
+
+				// Open zip file to prepare its extraction
+				status = unzOpenCurrentFile(file);
+				if (status != UNZ_OK)
+				{
+					spdlog::error("Could not open file {} from archive.", zipFilename);
+					modState.state = FAILED_READING_ARCHIVE;
+					goto EXTRACTION_CLEANUP;
+				}
+
+				// Create destination file
+				fout = fopen(fileDestination.generic_string().c_str(), "wb");
+				if (fout == NULL)
+				{
+					spdlog::error("Failed creating destination file.");
+					modState.state = FAILED_WRITING_TO_DISK;
+					goto EXTRACTION_CLEANUP;
+				}
+
+				// Allocate memory for buffer
+				buffer = (void*)malloc(bufferSize);
+				if (buffer == NULL)
+				{
+					spdlog::error("Error while allocating memory.");
+					modState.state = FAILED_WRITING_TO_DISK;
+					goto EXTRACTION_CLEANUP;
+				}
+
+				// Extract file to destination
+				do
+				{
+					err = unzReadCurrentFile(file, buffer, bufferSize);
+					if (err < 0)
+					{
+						spdlog::error("error {} with zipfile in unzReadCurrentFile", err);
+						break;
+					}
+					if (err > 0)
+					{
+						if (fwrite(buffer, (unsigned)err, 1, fout) != 1)
+						{
+							spdlog::error("error in writing extracted file\n");
+							err = UNZ_ERRNO;
+							break;
+						}
+					}
+
+					// Update extraction stats
+					modState.progress += bufferSize;
+					modState.ratio = roundf(static_cast<float>(modState.progress) / modState.total * 100);
+				} while (err > 0);
+
+				if (err != UNZ_OK)
+				{
+					spdlog::error("An error occurred during file extraction (code: {})", err);
+					modState.state = FAILED_WRITING_TO_DISK;
+					goto EXTRACTION_CLEANUP;
+				}
+				err = unzCloseCurrentFile(file);
+				if (err != UNZ_OK)
+				{
+					spdlog::error("error {} with zipfile in unzCloseCurrentFile", err);
+				}
+
+				// Cleanup
+				if (fout)
+					fclose(fout);
+			}
+		}
+
+		// Go to next file
+		if ((i + 1) < gi.number_entry)
+		{
+			status = unzGoToNextFile(file);
+			if (status != UNZ_OK)
+			{
+				spdlog::error("Error while browsing archive files (error code: {}).", status);
+				goto EXTRACTION_CLEANUP;
+			}
+		}
+	}
+
+EXTRACTION_CLEANUP:
+	if (unzClose(file) != MZ_OK)
+	{
+		spdlog::error("Failed closing mod archive after extraction.");
+	}
+}
+
+void ModDownloader::DownloadMod(std::string modName, std::string modVersion)
+{
+	// Check if mod can be auto-downloaded
+	if (!IsModAuthorized(std::string_view(modName), std::string_view(modVersion)))
+	{
+		spdlog::warn("Tried to download a mod that is not verified, aborting.");
+		return;
+	}
+
+	std::thread requestThread(
+		[this, modName, modVersion]()
+		{
+			fs::path archiveLocation;
+
+			// Download mod archive
+			std::string expectedHash = verifiedMods[modName].versions[modVersion].checksum;
+			std::optional<fs::path> fetchingResult = FetchModFromDistantStore(std::string_view(modName), std::string_view(modVersion));
+			if (!fetchingResult.has_value())
+			{
+				spdlog::error("Something went wrong while fetching archive, aborting.");
+				modState.state = MOD_FETCHING_FAILED;
+				goto REQUEST_END_CLEANUP;
+			}
+			archiveLocation = fetchingResult.value();
+			if (!IsModLegit(archiveLocation, std::string_view(expectedHash)))
+			{
+				spdlog::warn("Archive hash does not match expected checksum, aborting.");
+				modState.state = MOD_CORRUPTED;
+				goto REQUEST_END_CLEANUP;
+			}
+
+			// Extract downloaded mod archive
+			ExtractMod(archiveLocation);
+
+		REQUEST_END_CLEANUP:
+			try
+			{
+				remove(archiveLocation);
+			}
+			catch (const std::exception& a)
+			{
+				spdlog::error("Error while removing downloaded archive: {}", a.what());
+			}
+
+			modState.state = DONE;
+			spdlog::info("Done downloading {}.", modName);
+		});
+
+	requestThread.detach();
+}
+
+ON_DLL_LOAD_RELIESON("engine.dll", ModDownloader, (ConCommand), (CModule module))
+{
+	g_pModDownloader = new ModDownloader();
+	g_pModDownloader->FetchModsListFromAPI();
+}
+
+ADD_SQFUNC(
+	"bool", NSIsModDownloadable, "string name, string version", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	g_pSquirrel<context>->newarray(sqvm, 0);
+
+	const SQChar* modName = g_pSquirrel<context>->getstring(sqvm, 1);
+	const SQChar* modVersion = g_pSquirrel<context>->getstring(sqvm, 2);
+
+	bool result = g_pModDownloader->IsModAuthorized(modName, modVersion);
+	g_pSquirrel<context>->pushbool(sqvm, result);
+
+	return SQRESULT_NOTNULL;
+}
+
+ADD_SQFUNC("void", NSDownloadMod, "string name, string version", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	const SQChar* modName = g_pSquirrel<context>->getstring(sqvm, 1);
+	const SQChar* modVersion = g_pSquirrel<context>->getstring(sqvm, 2);
+	g_pModDownloader->DownloadMod(modName, modVersion);
+
+	return SQRESULT_NOTNULL;
+}
+
+ADD_SQFUNC("ModInstallState", NSGetModInstallState, "", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	g_pSquirrel<context>->pushnewstructinstance(sqvm, 4);
+
+	// state
+	g_pSquirrel<context>->pushinteger(sqvm, g_pModDownloader->modState.state);
+	g_pSquirrel<context>->sealstructslot(sqvm, 0);
+
+	// progress
+	g_pSquirrel<context>->pushinteger(sqvm, g_pModDownloader->modState.progress);
+	g_pSquirrel<context>->sealstructslot(sqvm, 1);
+
+	// total
+	g_pSquirrel<context>->pushinteger(sqvm, g_pModDownloader->modState.total);
+	g_pSquirrel<context>->sealstructslot(sqvm, 2);
+
+	// ratio
+	g_pSquirrel<context>->pushfloat(sqvm, g_pModDownloader->modState.ratio);
+	g_pSquirrel<context>->sealstructslot(sqvm, 3);
+
+	return SQRESULT_NOTNULL;
+}
diff --git a/primedev/mods/autodownload/moddownloader.h b/primedev/mods/autodownload/moddownloader.h
new file mode 100644
index 00000000..5302c21e
--- /dev/null
+++ b/primedev/mods/autodownload/moddownloader.h
@@ -0,0 +1,151 @@
+class ModDownloader
+{
+private:
+	const char* VERIFICATION_FLAG = "-disablemodverification";
+	const char* CUSTOM_MODS_URL_FLAG = "-customverifiedurl=";
+	const char* STORE_URL = "https://gcdn.thunderstore.io/live/repository/packages/";
+	const char* DEFAULT_MODS_LIST_URL = "https://raw.githubusercontent.com/R2Northstar/VerifiedMods/master/verified-mods.json";
+	char* modsListUrl;
+
+	struct VerifiedModVersion
+	{
+		std::string checksum;
+	};
+	struct VerifiedModDetails
+	{
+		std::string dependencyPrefix;
+		std::unordered_map<std::string, VerifiedModVersion> versions = {};
+	};
+	std::unordered_map<std::string, VerifiedModDetails> verifiedMods = {};
+
+	/**
+	 * Mod archive download callback.
+	 *
+	 * This function is called by curl as it's downloading the mod archive; this
+	 * will retrieve the current `ModDownloader` instance and update its `modState`
+	 * member accordingly.
+	 */
+	static int ModFetchingProgressCallback(
+		void* ptr, curl_off_t totalDownloadSize, curl_off_t finishedDownloadSize, curl_off_t totalToUpload, curl_off_t nowUploaded);
+
+	/**
+	 * Downloads a mod archive from distant store.
+	 *
+	 * This rebuilds the URI of the mod archive using both a predefined store URI
+	 * and the mod dependency string from the `verifiedMods` variable, or using
+	 * input mod name as mod dependency string if bypass flag is set up; fetched
+	 * archive is then stored in a temporary location.
+	 *
+	 * If something went wrong during archive download, this will return an empty
+	 * optional object.
+	 *
+	 * @param modName name of the mod to be downloaded
+	 * @param modVersion version of the mod to be downloaded
+	 * @returns location of the downloaded archive
+	 */
+	std::optional<fs::path> FetchModFromDistantStore(std::string_view modName, std::string_view modVersion);
+
+	/**
+	 * Tells if a mod archive has not been corrupted.
+	 *
+	 * The mod validation procedure includes computing the SHA256 hash of the final
+	 * archive, which is stored in the verified mods list. This hash is used by this
+	 * very method to ensure the archive downloaded from the Internet is the exact
+	 * same that has been manually verified.
+	 *
+	 * @param modPath path of the archive to check
+	 * @param expectedChecksum checksum the archive should have
+	 * @returns whether archive is legit
+	 */
+	bool IsModLegit(fs::path modPath, std::string_view expectedChecksum);
+
+	/**
+	 * Extracts a mod archive to the game folder.
+	 *
+	 * This extracts a downloaded mod archive from its original location to the
+	 * current game profile, in the remote mods folder.
+	 *
+	 * @param modPath location of the downloaded archive
+	 * @returns nothing
+	 */
+	void ExtractMod(fs::path modPath);
+
+public:
+	ModDownloader();
+
+	/**
+	 * Retrieves the verified mods list from the central authority.
+	 *
+	 * The Northstar auto-downloading feature does NOT allow automatically installing
+	 * all mods for various (notably security) reasons; mods that are candidate to
+	 * auto-downloading are rather listed on a GitHub repository
+	 * (https://raw.githubusercontent.com/R2Northstar/VerifiedMods/master/verified-mods.json),
+	 * which this method gets via a HTTP call to load into local state.
+	 *
+	 * If list fetching fails, local mods list will be initialized as empty, thus
+	 * preventing any mod from being auto-downloaded.
+	 *
+	 * @returns nothing
+	 */
+	void FetchModsListFromAPI();
+
+	/**
+	 * Checks whether a mod is verified.
+	 *
+	 * A mod is deemed verified/authorized through a manual validation process that is
+	 * described here: https://github.com/R2Northstar/VerifiedMods; in practice, a mod
+	 * is considered authorized if their name AND exact version appear in the
+	 * `verifiedMods` variable.
+	 *
+	 * @param modName name of the mod to be checked
+	 * @param modVersion version of the mod to be checked, must follow semantic versioning
+	 * @returns whether the mod is authorized and can be auto-downloaded
+	 */
+	bool IsModAuthorized(std::string_view modName, std::string_view modVersion);
+
+	/**
+	 * Downloads a given mod from Thunderstore API to local game profile.
+	 *
+	 * @param modName name of the mod to be downloaded
+	 * @param modVersion version of the mod to be downloaded
+	 * @returns nothing
+	 **/
+	void DownloadMod(std::string modName, std::string modVersion);
+
+	enum ModInstallState
+	{
+		// Normal installation process
+		DOWNLOADING,
+		CHECKSUMING,
+		EXTRACTING,
+		DONE, // Everything went great, mod can be used in-game
+
+		// Errors
+		FAILED, // Generic error message, should be avoided as much as possible
+		FAILED_READING_ARCHIVE,
+		FAILED_WRITING_TO_DISK,
+		MOD_FETCHING_FAILED,
+		MOD_CORRUPTED, // Downloaded archive checksum does not match verified hash
+		NO_DISK_SPACE_AVAILABLE,
+		NOT_FOUND // Mod is not currently being auto-downloaded
+	};
+
+	struct MOD_STATE
+	{
+		ModInstallState state;
+		int progress;
+		int total;
+		float ratio;
+	} modState = {};
+
+	/**
+	 * Cancels installation of the mod.
+	 *
+	 * Prevents installation of the mod currently being installed, no matter the install
+	 * progress (downloading, checksuming, extracting), and frees all resources currently
+	 * being used in this purpose.
+	 *
+	 * @returns nothing
+	 */
+	void CancelDownload();
+};
diff --git a/primedev/mods/compiled/kb_act.cpp b/primedev/mods/compiled/kb_act.cpp
new file mode 100644
index 00000000..6117fd28
--- /dev/null
+++ b/primedev/mods/compiled/kb_act.cpp
@@ -0,0 +1,44 @@
+#include "mods/modmanager.h"
+#include "core/filesystem/filesystem.h"
+
+#include <fstream>
+
+const char* KB_ACT_PATH = "scripts\\kb_act.lst";
+
+// compiles the file kb_act.lst, that defines entries for keybindings in the options menu
+void ModManager::BuildKBActionsList()
+{
+	spdlog::info("Building kb_act.lst");
+
+	fs::create_directories(GetCompiledAssetsPath() / "scripts");
+	std::ofstream soCompiledKeys(GetCompiledAssetsPath() / KB_ACT_PATH, std::ios::binary);
+
+	// write vanilla file's content to compiled file
+	soCompiledKeys << ReadVPKOriginalFile(KB_ACT_PATH);
+
+	for (Mod& mod : m_LoadedMods)
+	{
+		if (!mod.m_bEnabled)
+			continue;
+
+		// write content of each modded file to compiled file
+		std::ifstream siModKeys(mod.m_ModDirectory / "kb_act.lst");
+
+		if (siModKeys.good())
+			soCompiledKeys << siModKeys.rdbuf() << std::endl;
+
+		siModKeys.close();
+	}
+
+	soCompiledKeys.close();
+
+	// push to overrides
+	ModOverrideFile overrideFile;
+	overrideFile.m_pOwningMod = nullptr;
+	overrideFile.m_Path = KB_ACT_PATH;
+
+	if (m_ModFiles.find(KB_ACT_PATH) == m_ModFiles.end())
+		m_ModFiles.insert(std::make_pair(KB_ACT_PATH, overrideFile));
+	else
+		m_ModFiles[KB_ACT_PATH] = overrideFile;
+}
diff --git a/primedev/mods/compiled/modkeyvalues.cpp b/primedev/mods/compiled/modkeyvalues.cpp
new file mode 100644
index 00000000..e44a81d3
--- /dev/null
+++ b/primedev/mods/compiled/modkeyvalues.cpp
@@ -0,0 +1,106 @@
+#include "mods/modmanager.h"
+#include "core/filesystem/filesystem.h"
+
+#include <fstream>
+
+AUTOHOOK_INIT()
+
+void ModManager::TryBuildKeyValues(const char* filename)
+{
+	spdlog::info("Building KeyValues for file {}", filename);
+
+	std::string normalisedPath = g_pModManager->NormaliseModFilePath(fs::path(filename));
+	fs::path compiledPath = GetCompiledAssetsPath() / filename;
+	fs::path compiledDir = compiledPath.parent_path();
+	fs::create_directories(compiledDir);
+
+	fs::path kvPath(filename);
+	std::string ogFilePath = "mod_original_";
+	ogFilePath += kvPath.filename().string();
+
+	std::string newKvs = "// AUTOGENERATED: MOD PATCH KV\n";
+
+	int patchNum = 0;
+
+	// copy over patch kv files, and add #bases to new file, last mods' patches should be applied first
+	// note: #include should be identical but it's actually just broken, thanks respawn
+	for (int64_t i = m_LoadedMods.size() - 1; i > -1; i--)
+	{
+		if (!m_LoadedMods[i].m_bEnabled)
+			continue;
+
+		size_t fileHash = STR_HASH(normalisedPath);
+		auto modKv = m_LoadedMods[i].KeyValues.find(fileHash);
+		if (modKv != m_LoadedMods[i].KeyValues.end())
+		{
+			// should result in smth along the lines of #include "mod_patch_5_mp_weapon_car.txt"
+
+			std::string patchFilePath = "mod_patch_";
+			patchFilePath += std::to_string(patchNum++);
+			patchFilePath += "_";
+			patchFilePath += kvPath.filename().string();
+
+			newKvs += "#base \"";
+			newKvs += patchFilePath;
+			newKvs += "\"\n";
+
+			fs::remove(compiledDir / patchFilePath);
+
+			fs::copy_file(m_LoadedMods[i].m_ModDirectory / "keyvalues" / filename, compiledDir / patchFilePath);
+		}
+	}
+
+	// add original #base last, #bases don't override preexisting keys, including the ones we've just done
+	newKvs += "#base \"";
+	newKvs += ogFilePath;
+	newKvs += "\"\n";
+
+	// load original file, so we can parse out the name of the root obj (e.g. WeaponData for weapons)
+	std::string originalFile = ReadVPKOriginalFile(filename);
+
+	if (!originalFile.length())
+	{
+		spdlog::warn("Tried to patch kv {} but no base kv was found!", ogFilePath);
+		return;
+	}
+
+	char rootName[64];
+	memset(rootName, 0, sizeof(rootName));
+
+	// iterate until we hit an ascii char that isn't in a # command or comment to get root obj name
+	int i = 0;
+	while (!(originalFile[i] >= 65 && originalFile[i] <= 122))
+	{
+		// if we hit a comment or # thing, iterate until end of line
+		if (originalFile[i] == '/' || originalFile[i] == '#')
+			while (originalFile[i] != '\n')
+				i++;
+
+		i++;
+	}
+
+	int j = 0;
+	for (int j = 0; originalFile[i] >= 65 && originalFile[i] <= 122; j++)
+		rootName[j] = originalFile[i++];
+
+	// empty kv, all the other stuff gets #base'd
+	newKvs += rootName;
+	newKvs += "\n{\n}\n";
+
+	std::ofstream originalFileWriteStream(compiledDir / ogFilePath, std::ios::binary);
+	originalFileWriteStream << originalFile;
+	originalFileWriteStream.close();
+
+	std::ofstream writeStream(compiledPath, std::ios::binary);
+	writeStream << newKvs;
+	writeStream.close();
+
+	ModOverrideFile overrideFile;
+	overrideFile.m_pOwningMod = nullptr;
+	overrideFile.m_Path = normalisedPath;
+
+	if (m_ModFiles.find(normalisedPath) == m_ModFiles.end())
+		m_ModFiles.insert(std::make_pair(normalisedPath, overrideFile));
+	else
+		m_ModFiles[normalisedPath] = overrideFile;
+}
diff --git a/primedev/mods/compiled/modpdef.cpp b/primedev/mods/compiled/modpdef.cpp
new file mode 100644
index 00000000..d268a063
--- /dev/null
+++ b/primedev/mods/compiled/modpdef.cpp
@@ -0,0 +1,118 @@
+#include "mods/modmanager.h"
+#include "core/filesystem/filesystem.h"
+
+#include <map>
+#include <sstream>
+#include <fstream>
+
+const fs::path MOD_PDEF_SUFFIX = "cfg/server/persistent_player_data_version_231.pdef";
+const char* VPK_PDEF_PATH = "cfg/server/persistent_player_data_version_231.pdef";
+
+void ModManager::BuildPdef()
+{
+	spdlog::info("Building persistent_player_data_version_231.pdef...");
+
+	fs::path MOD_PDEF_PATH = fs::path(GetCompiledAssetsPath() / MOD_PDEF_SUFFIX);
+
+	fs::remove(MOD_PDEF_PATH);
+	std::string pdef = ReadVPKOriginalFile(VPK_PDEF_PATH);
+
+	for (Mod& mod : m_LoadedMods)
+	{
+		if (!mod.m_bEnabled || !mod.Pdiff.size())
+			continue;
+
+		// this code probably isn't going to be pretty lol
+		// refer to shared/pjson.js for an actual okish parser of the pdiff format
+		// but pretty much, $ENUM_ADD blocks define members added to preexisting enums
+		// $PROP_START ends the custom stuff, and from there it's just normal props we append to the pdef
+
+		std::map<std::string, std::vector<std::string>> enumAdds;
+
+		// read pdiff
+		bool inEnum = false;
+		bool inProp = false;
+		std::string currentEnum;
+		std::string currentLine;
+		std::istringstream pdiffStream(mod.Pdiff);
+
+		while (std::getline(pdiffStream, currentLine))
+		{
+			if (inProp)
+			{
+				// just append to pdef here
+				pdef += currentLine;
+				pdef += '\n';
+				continue;
+			}
+
+			// trim leading whitespace
+			size_t start = currentLine.find_first_not_of(" \n\r\t\f\v");
+			size_t end = currentLine.find("//");
+			if (end == std::string::npos)
+				end = currentLine.size() - 1; // last char
+
+			if (!currentLine.size() || !currentLine.compare(start, 2, "//"))
+				continue;
+
+			if (inEnum)
+			{
+				if (!currentLine.compare(start, 9, "$ENUM_END"))
+					inEnum = false;
+				else
+					enumAdds[currentEnum].push_back(currentLine); // only need to push_back current line, if there's syntax errors then game
+																  // pdef parser will handle them
+			}
+			else if (!currentLine.compare(start, 9, "$ENUM_ADD"))
+			{
+				inEnum = true;
+				currentEnum = currentLine.substr(start + 10 /*$ENUM_ADD + 1*/, currentLine.size() - end - (start + 10));
+				enumAdds.insert(std::make_pair(currentEnum, std::vector<std::string>()));
+			}
+			else if (!currentLine.compare(start, 11, "$PROP_START"))
+			{
+				inProp = true;
+				pdef += "\n// $PROP_START ";
+				pdef += mod.Name;
+				pdef += "\n";
+			}
+		}
+
+		// add new members to preexisting enums
+		// note: this code could 100% be messed up if people put //$ENUM_START comments and the like
+		// could make it protect against this, but honestly not worth atm
+		for (auto enumAdd : enumAdds)
+		{
+			std::string addStr;
+			for (std::string enumMember : enumAdd.second)
+			{
+				addStr += enumMember;
+				addStr += '\n';
+			}
+
+			// start of enum we're adding to
+			std::string startStr = "$ENUM_START ";
+			startStr += enumAdd.first;
+
+			// insert enum values into enum
+			size_t insertIdx = pdef.find("$ENUM_END", pdef.find(startStr));
+			pdef.reserve(addStr.size());
+			pdef.insert(insertIdx, addStr);
+		}
+	}
+
+	fs::create_directories(MOD_PDEF_PATH.parent_path());
+
+	std::ofstream writeStream(MOD_PDEF_PATH, std::ios::binary);
+	writeStream << pdef;
+	writeStream.close();
+
+	ModOverrideFile overrideFile;
+	overrideFile.m_pOwningMod = nullptr;
+	overrideFile.m_Path = VPK_PDEF_PATH;
+
+	if (m_ModFiles.find(VPK_PDEF_PATH) == m_ModFiles.end())
+		m_ModFiles.insert(std::make_pair(VPK_PDEF_PATH, overrideFile));
+	else
+		m_ModFiles[VPK_PDEF_PATH] = overrideFile;
+}
diff --git a/primedev/mods/compiled/modscriptsrson.cpp b/primedev/mods/compiled/modscriptsrson.cpp
new file mode 100644
index 00000000..d130745f
--- /dev/null
+++ b/primedev/mods/compiled/modscriptsrson.cpp
@@ -0,0 +1,65 @@
+#include "mods/modmanager.h"
+#include "core/filesystem/filesystem.h"
+#include "squirrel/squirrel.h"
+
+#include <fstream>
+
+const std::string MOD_SCRIPTS_RSON_SUFFIX = "scripts/vscripts/scripts.rson";
+const char* VPK_SCRIPTS_RSON_PATH = "scripts\\vscripts\\scripts.rson";
+
+void ModManager::BuildScriptsRson()
+{
+	spdlog::info("Building custom scripts.rson");
+	fs::path MOD_SCRIPTS_RSON_PATH = fs::path(GetCompiledAssetsPath() / MOD_SCRIPTS_RSON_SUFFIX);
+	fs::remove(MOD_SCRIPTS_RSON_PATH);
+
+	std::string scriptsRson = ReadVPKOriginalFile(VPK_SCRIPTS_RSON_PATH);
+	scriptsRson += "\n\n// START MODDED SCRIPT CONTENT\n\n"; // newline before we start custom stuff
+
+	for (Mod& mod : m_LoadedMods)
+	{
+		if (!mod.m_bEnabled)
+			continue;
+
+		// this isn't needed at all, just nice to have imo
+		scriptsRson += "// MOD: ";
+		scriptsRson += mod.Name;
+		scriptsRson += ":\n\n";
+
+		for (ModScript& script : mod.Scripts)
+		{
+			/* should create something with this format for each script
+			When: "CONTEXT"
+			Scripts:
+			[
+				_coolscript.gnut
+			]*/
+
+			scriptsRson += "When: \"";
+			scriptsRson += script.RunOn;
+			scriptsRson += "\"\n";
+
+			scriptsRson += "Scripts:\n[\n\t";
+			scriptsRson += script.Path;
+			scriptsRson += "\n]\n\n";
+		}
+	}
+
+	fs::create_directories(MOD_SCRIPTS_RSON_PATH.parent_path());
+
+	std::ofstream writeStream(MOD_SCRIPTS_RSON_PATH, std::ios::binary);
+	writeStream << scriptsRson;
+	writeStream.close();
+
+	ModOverrideFile overrideFile;
+	overrideFile.m_pOwningMod = nullptr;
+	overrideFile.m_Path = VPK_SCRIPTS_RSON_PATH;
+
+	if (m_ModFiles.find(VPK_SCRIPTS_RSON_PATH) == m_ModFiles.end())
+		m_ModFiles.insert(std::make_pair(VPK_SCRIPTS_RSON_PATH, overrideFile));
+	else
+		m_ModFiles[VPK_SCRIPTS_RSON_PATH] = overrideFile;
+
+	// todo: for preventing dupe scripts in scripts.rson, we could actually parse when conditions with the squirrel vm, just need a way to
+	// get a result out of squirrelmanager.ExecuteCode this would probably be the best way to do this, imo
+}
diff --git a/primedev/mods/modmanager.cpp b/primedev/mods/modmanager.cpp
new file mode 100644
index 00000000..8a0eb71d
--- /dev/null
+++ b/primedev/mods/modmanager.cpp
@@ -0,0 +1,1150 @@
+#include "modmanager.h"
+#include "core/convar/convar.h"
+#include "core/convar/concommand.h"
+#include "client/audio.h"
+#include "masterserver/masterserver.h"
+#include "core/filesystem/filesystem.h"
+#include "core/filesystem/rpakfilesystem.h"
+#include "config/profile.h"
+
+#include "rapidjson/error/en.h"
+#include "rapidjson/document.h"
+#include "rapidjson/ostreamwrapper.h"
+#include "rapidjson/prettywriter.h"
+#include <filesystem>
+#include <fstream>
+#include <string>
+#include <sstream>
+#include <vector>
+#include <regex>
+
+ModManager* g_pModManager;
+
+Mod::Mod(fs::path modDir, char* jsonBuf)
+{
+	m_bWasReadSuccessfully = false;
+
+	m_ModDirectory = modDir;
+
+	rapidjson_document modJson;
+	modJson.Parse<rapidjson::ParseFlag::kParseCommentsFlag | rapidjson::ParseFlag::kParseTrailingCommasFlag>(jsonBuf);
+
+	spdlog::info("Loading mod file at path '{}'", modDir.string());
+
+	// fail if parse error
+	if (modJson.HasParseError())
+	{
+		spdlog::error(
+			"Failed reading mod file {}: encountered parse error \"{}\" at offset {}",
+			(modDir / "mod.json").string(),
+			GetParseError_En(modJson.GetParseError()),
+			modJson.GetErrorOffset());
+		return;
+	}
+
+	// fail if it's not a json obj (could be an array, string, etc)
+	if (!modJson.IsObject())
+	{
+		spdlog::error("Failed reading mod file {}: file is not a JSON object", (modDir / "mod.json").string());
+		return;
+	}
+
+	// basic mod info
+	// name is required
+	if (!modJson.HasMember("Name"))
+	{
+		spdlog::error("Failed reading mod file {}: missing required member \"Name\"", (modDir / "mod.json").string());
+		return;
+	}
+
+	Name = modJson["Name"].GetString();
+	spdlog::info("Loading mod '{}'", Name);
+
+	// Don't load blacklisted mods
+	if (!strstr(GetCommandLineA(), "-nomodblacklist") && MODS_BLACKLIST.find(Name) != std::end(MODS_BLACKLIST))
+	{
+		spdlog::warn("Skipping blacklisted mod \"{}\"!", Name);
+		return;
+	}
+
+	if (modJson.HasMember("Description"))
+		Description = modJson["Description"].GetString();
+	else
+		Description = "";
+
+	if (modJson.HasMember("Version"))
+		Version = modJson["Version"].GetString();
+	else
+	{
+		Version = "0.0.0";
+		spdlog::warn("Mod file {} is missing a version, consider adding a version", (modDir / "mod.json").string());
+	}
+
+	if (modJson.HasMember("DownloadLink"))
+		DownloadLink = modJson["DownloadLink"].GetString();
+	else
+		DownloadLink = "";
+
+	if (modJson.HasMember("RequiredOnClient"))
+		RequiredOnClient = modJson["RequiredOnClient"].GetBool();
+	else
+		RequiredOnClient = false;
+
+	if (modJson.HasMember("LoadPriority"))
+		LoadPriority = modJson["LoadPriority"].GetInt();
+	else
+	{
+		spdlog::info("Mod file {} is missing a LoadPriority, consider adding one", (modDir / "mod.json").string());
+		LoadPriority = 0;
+	}
+
+	// Parse all array fields
+	ParseConVars(modJson);
+	ParseConCommands(modJson);
+	ParseScripts(modJson);
+	ParseLocalization(modJson);
+	ParseDependencies(modJson);
+	ParsePluginDependencies(modJson);
+	ParseInitScript(modJson);
+
+	// A mod is remote if it's located in the remote mods folder
+	m_bIsRemote = m_ModDirectory.generic_string().find(GetRemoteModFolderPath().generic_string()) != std::string::npos;
+
+	m_bWasReadSuccessfully = true;
+}
+
+void Mod::ParseConVars(rapidjson_document& json)
+{
+	if (!json.HasMember("ConVars"))
+		return;
+
+	if (!json["ConVars"].IsArray())
+	{
+		spdlog::warn("'ConVars' field is not an array, skipping...");
+		return;
+	}
+
+	for (auto& convarObj : json["ConVars"].GetArray())
+	{
+		if (!convarObj.IsObject())
+		{
+			spdlog::warn("ConVar is not an object, skipping...");
+			continue;
+		}
+		if (!convarObj.HasMember("Name"))
+		{
+			spdlog::warn("ConVar does not have a Name, skipping...");
+			continue;
+		}
+		// from here on, the ConVar can be referenced by name in logs
+		if (!convarObj.HasMember("DefaultValue"))
+		{
+			spdlog::warn("ConVar '{}' does not have a DefaultValue, skipping...", convarObj["Name"].GetString());
+			continue;
+		}
+
+		// have to allocate this manually, otherwise convar registration will break
+		// unfortunately this causes us to leak memory on reload, unsure of a way around this rn
+		ModConVar* convar = new ModConVar;
+		convar->Name = convarObj["Name"].GetString();
+		convar->DefaultValue = convarObj["DefaultValue"].GetString();
+
+		if (convarObj.HasMember("HelpString"))
+			convar->HelpString = convarObj["HelpString"].GetString();
+		else
+			convar->HelpString = "";
+
+		convar->Flags = FCVAR_NONE;
+
+		if (convarObj.HasMember("Flags"))
+		{
+			// read raw integer flags
+			if (convarObj["Flags"].IsInt())
+				convar->Flags = convarObj["Flags"].GetInt();
+			else if (convarObj["Flags"].IsString())
+			{
+				// parse cvar flags from string
+				// example string: ARCHIVE_PLAYERPROFILE | GAMEDLL
+				convar->Flags |= ParseConVarFlagsString(convar->Name, convarObj["Flags"].GetString());
+			}
+		}
+
+		ConVars.push_back(convar);
+
+		spdlog::info("'{}' contains ConVar '{}'", Name, convar->Name);
+	}
+}
+
+void Mod::ParseConCommands(rapidjson_document& json)
+{
+	if (!json.HasMember("ConCommands"))
+		return;
+
+	if (!json["ConCommands"].IsArray())
+	{
+		spdlog::warn("'ConCommands' field is not an array, skipping...");
+		return;
+	}
+
+	for (auto& concommandObj : json["ConCommands"].GetArray())
+	{
+		if (!concommandObj.IsObject())
+		{
+			spdlog::warn("ConCommand is not an object, skipping...");
+			continue;
+		}
+		if (!concommandObj.HasMember("Name"))
+		{
+			spdlog::warn("ConCommand does not have a Name, skipping...");
+			continue;
+		}
+		// from here on, the ConCommand can be referenced by name in logs
+		if (!concommandObj.HasMember("Function"))
+		{
+			spdlog::warn("ConCommand '{}' does not have a Function, skipping...", concommandObj["Name"].GetString());
+			continue;
+		}
+		if (!concommandObj.HasMember("Context"))
+		{
+			spdlog::warn("ConCommand '{}' does not have a Context, skipping...", concommandObj["Name"].GetString());
+			continue;
+		}
+
+		// have to allocate this manually, otherwise concommand registration will break
+		// unfortunately this causes us to leak memory on reload, unsure of a way around this rn
+		ModConCommand* concommand = new ModConCommand;
+		concommand->Name = concommandObj["Name"].GetString();
+		concommand->Function = concommandObj["Function"].GetString();
+		concommand->Context = ScriptContextFromString(concommandObj["Context"].GetString());
+		if (concommand->Context == ScriptContext::INVALID)
+		{
+			spdlog::warn("ConCommand '{}' has invalid context '{}', skipping...", concommand->Name, concommandObj["Context"].GetString());
+			continue;
+		}
+
+		if (concommandObj.HasMember("HelpString"))
+			concommand->HelpString = concommandObj["HelpString"].GetString();
+		else
+			concommand->HelpString = "";
+
+		concommand->Flags = FCVAR_NONE;
+
+		if (concommandObj.HasMember("Flags"))
+		{
+			// read raw integer flags
+			if (concommandObj["Flags"].IsInt())
+			{
+				concommand->Flags = concommandObj["Flags"].GetInt();
+			}
+			else if (concommandObj["Flags"].IsString())
+			{
+				// parse cvar flags from string
+				// example string: ARCHIVE_PLAYERPROFILE | GAMEDLL
+				concommand->Flags |= ParseConVarFlagsString(concommand->Name, concommandObj["Flags"].GetString());
+			}
+		}
+
+		ConCommands.push_back(concommand);
+
+		spdlog::info("'{}' contains ConCommand '{}'", Name, concommand->Name);
+	}
+}
+
+void Mod::ParseScripts(rapidjson_document& json)
+{
+	if (!json.HasMember("Scripts"))
+		return;
+
+	if (!json["Scripts"].IsArray())
+	{
+		spdlog::warn("'Scripts' field is not an array, skipping...");
+		return;
+	}
+
+	for (auto& scriptObj : json["Scripts"].GetArray())
+	{
+		if (!scriptObj.IsObject())
+		{
+			spdlog::warn("Script is not an object, skipping...");
+			continue;
+		}
+		if (!scriptObj.HasMember("Path"))
+		{
+			spdlog::warn("Script does not have a Path, skipping...");
+			continue;
+		}
+		// from here on, the Path for a script is used as it's name in logs
+		if (!scriptObj.HasMember("RunOn"))
+		{
+			// "a RunOn" sounds dumb but anything else doesn't match the format of the warnings...
+			// this is the best i could think of within 20 seconds
+			spdlog::warn("Script '{}' does not have a RunOn field, skipping...", scriptObj["Path"].GetString());
+			continue;
+		}
+
+		ModScript script;
+
+		script.Path = scriptObj["Path"].GetString();
+		script.RunOn = scriptObj["RunOn"].GetString();
+
+		if (scriptObj.HasMember("ServerCallback"))
+		{
+			if (scriptObj["ServerCallback"].IsObject())
+			{
+				ModScriptCallback callback;
+				callback.Context = ScriptContext::SERVER;
+
+				if (scriptObj["ServerCallback"].HasMember("Before"))
+				{
+					if (scriptObj["ServerCallback"]["Before"].IsString())
+						callback.BeforeCallback = scriptObj["ServerCallback"]["Before"].GetString();
+					else
+						spdlog::warn("'Before' ServerCallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				if (scriptObj["ServerCallback"].HasMember("After"))
+				{
+					if (scriptObj["ServerCallback"]["After"].IsString())
+						callback.AfterCallback = scriptObj["ServerCallback"]["After"].GetString();
+					else
+						spdlog::warn("'After' ServerCallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				if (scriptObj["ServerCallback"].HasMember("Destroy"))
+				{
+					if (scriptObj["ServerCallback"]["Destroy"].IsString())
+						callback.DestroyCallback = scriptObj["ServerCallback"]["Destroy"].GetString();
+					else
+						spdlog::warn(
+							"'Destroy' ServerCallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				script.Callbacks.push_back(callback);
+			}
+			else
+			{
+				spdlog::warn("ServerCallback for script '{}' is not an object, skipping...", scriptObj["Path"].GetString());
+			}
+		}
+
+		if (scriptObj.HasMember("ClientCallback"))
+		{
+			if (scriptObj["ClientCallback"].IsObject())
+			{
+				ModScriptCallback callback;
+				callback.Context = ScriptContext::CLIENT;
+
+				if (scriptObj["ClientCallback"].HasMember("Before"))
+				{
+					if (scriptObj["ClientCallback"]["Before"].IsString())
+						callback.BeforeCallback = scriptObj["ClientCallback"]["Before"].GetString();
+					else
+						spdlog::warn("'Before' ClientCallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				if (scriptObj["ClientCallback"].HasMember("After"))
+				{
+					if (scriptObj["ClientCallback"]["After"].IsString())
+						callback.AfterCallback = scriptObj["ClientCallback"]["After"].GetString();
+					else
+						spdlog::warn("'After' ClientCallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				if (scriptObj["ClientCallback"].HasMember("Destroy"))
+				{
+					if (scriptObj["ClientCallback"]["Destroy"].IsString())
+						callback.DestroyCallback = scriptObj["ClientCallback"]["Destroy"].GetString();
+					else
+						spdlog::warn(
+							"'Destroy' ClientCallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				script.Callbacks.push_back(callback);
+			}
+			else
+			{
+				spdlog::warn("ClientCallback for script '{}' is not an object, skipping...", scriptObj["Path"].GetString());
+			}
+		}
+
+		if (scriptObj.HasMember("UICallback"))
+		{
+			if (scriptObj["UICallback"].IsObject())
+			{
+				ModScriptCallback callback;
+				callback.Context = ScriptContext::UI;
+
+				if (scriptObj["UICallback"].HasMember("Before"))
+				{
+					if (scriptObj["UICallback"]["Before"].IsString())
+						callback.BeforeCallback = scriptObj["UICallback"]["Before"].GetString();
+					else
+						spdlog::warn("'Before' UICallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				if (scriptObj["UICallback"].HasMember("After"))
+				{
+					if (scriptObj["UICallback"]["After"].IsString())
+						callback.AfterCallback = scriptObj["UICallback"]["After"].GetString();
+					else
+						spdlog::warn("'After' UICallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				if (scriptObj["UICallback"].HasMember("Destroy"))
+				{
+					if (scriptObj["UICallback"]["Destroy"].IsString())
+						callback.DestroyCallback = scriptObj["UICallback"]["Destroy"].GetString();
+					else
+						spdlog::warn("'Destroy' UICallback for script '{}' is not a string, skipping...", scriptObj["Path"].GetString());
+				}
+
+				script.Callbacks.push_back(callback);
+			}
+			else
+			{
+				spdlog::warn("UICallback for script '{}' is not an object, skipping...", scriptObj["Path"].GetString());
+			}
+		}
+
+		Scripts.push_back(script);
+
+		spdlog::info("'{}' contains Script '{}'", Name, script.Path);
+	}
+}
+
+void Mod::ParseLocalization(rapidjson_document& json)
+{
+	if (!json.HasMember("Localisation"))
+		return;
+
+	if (!json["Localisation"].IsArray())
+	{
+		spdlog::warn("'Localisation' field is not an array, skipping...");
+		return;
+	}
+
+	for (auto& localisationStr : json["Localisation"].GetArray())
+	{
+		if (!localisationStr.IsString())
+		{
+			// not a string but we still GetString() to log it :trol:
+			spdlog::warn("Localisation '{}' is not a string, skipping...", localisationStr.GetString());
+			continue;
+		}
+
+		LocalisationFiles.push_back(localisationStr.GetString());
+
+		spdlog::info("'{}' registered Localisation '{}'", Name, localisationStr.GetString());
+	}
+}
+
+void Mod::ParseDependencies(rapidjson_document& json)
+{
+	if (!json.HasMember("Dependencies"))
+		return;
+
+	if (!json["Dependencies"].IsObject())
+	{
+		spdlog::warn("'Dependencies' field is not an object, skipping...");
+		return;
+	}
+
+	for (auto v = json["Dependencies"].MemberBegin(); v != json["Dependencies"].MemberEnd(); v++)
+	{
+		if (!v->name.IsString())
+		{
+			spdlog::warn("Dependency constant '{}' is not a string, skipping...", v->name.GetString());
+			continue;
+		}
+		if (!v->value.IsString())
+		{
+			spdlog::warn("Dependency constant '{}' is not a string, skipping...", v->value.GetString());
+			continue;
+		}
+
+		if (DependencyConstants.find(v->name.GetString()) != DependencyConstants.end() &&
+			v->value.GetString() != DependencyConstants[v->name.GetString()])
+		{
+			// this is fatal because otherwise the mod will probably try to use functions that dont exist,
+			// which will cause errors further down the line that are harder to debug
+			spdlog::error(
+				"'{}' attempted to register a dependency constant '{}' for '{}' that already exists for '{}'. "
+				"Change the constant name.",
+				Name,
+				v->name.GetString(),
+				v->value.GetString(),
+				DependencyConstants[v->name.GetString()]);
+			return;
+		}
+
+		if (DependencyConstants.find(v->name.GetString()) == DependencyConstants.end())
+			DependencyConstants.emplace(v->name.GetString(), v->value.GetString());
+
+		spdlog::info("'{}' registered dependency constant '{}' for mod '{}'", Name, v->name.GetString(), v->value.GetString());
+	}
+}
+
+void Mod::ParsePluginDependencies(rapidjson_document& json)
+{
+	if (!json.HasMember("PluginDependencies"))
+		return;
+
+	if (!json["PluginDependencies"].IsArray())
+	{
+		spdlog::warn("'PluginDependencies' field is not an object, skipping...");
+		return;
+	}
+
+	for (auto& name : json["PluginDependencies"].GetArray())
+	{
+		if (!name.IsString())
+			continue;
+
+		spdlog::info("Plugin Constant {} defined by {}", name.GetString(), Name);
+
+		PluginDependencyConstants.push_back(name.GetString());
+	}
+}
+
+void Mod::ParseInitScript(rapidjson_document& json)
+{
+	if (!json.HasMember("InitScript"))
+		return;
+
+	if (!json["InitScript"].IsString())
+	{
+		spdlog::warn("'InitScript' field is not a string, skipping...");
+		return;
+	}
+
+	initScript = json["InitScript"].GetString();
+}
+
+ModManager::ModManager()
+{
+	// precaculated string hashes
+	// note: use backslashes for these, since we use lexically_normal for file paths which uses them
+	m_hScriptsRsonHash = STR_HASH("scripts\\vscripts\\scripts.rson");
+	m_hPdefHash = STR_HASH(
+		"cfg\\server\\persistent_player_data_version_231.pdef" // this can have multiple versions, but we use 231 so that's what we hash
+	);
+	m_hKBActHash = STR_HASH("scripts\\kb_act.lst");
+
+	LoadMods();
+}
+
+struct Test
+{
+	std::string funcName;
+	ScriptContext context;
+};
+
+template <ScriptContext context> auto ModConCommandCallback_Internal(std::string name, const CCommand& command)
+{
+	if (g_pSquirrel<context>->m_pSQVM && g_pSquirrel<context>->m_pSQVM)
+	{
+		if (command.ArgC() == 1)
+		{
+			g_pSquirrel<context>->AsyncCall(name);
+		}
+		else
+		{
+			std::vector<std::string> args;
+			args.reserve(command.ArgC());
+			for (int i = 1; i < command.ArgC(); i++)
+				args.push_back(command.Arg(i));
+			g_pSquirrel<context>->AsyncCall(name, args);
+		}
+	}
+	else
+	{
+		spdlog::warn("ConCommand `{}` was called while the associated Squirrel VM `{}` was unloaded", name, GetContextName(context));
+	}
+}
+
+auto ModConCommandCallback(const CCommand& command)
+{
+	ModConCommand* found = nullptr;
+	auto commandString = std::string(command.GetCommandString());
+
+	// Finding the first space to remove the command's name
+	auto firstSpace = commandString.find(' ');
+	if (firstSpace)
+	{
+		commandString = commandString.substr(0, firstSpace);
+	}
+
+	// Find the mod this command belongs to
+	for (auto& mod : g_pModManager->m_LoadedMods)
+	{
+		auto res = std::find_if(
+			mod.ConCommands.begin(),
+			mod.ConCommands.end(),
+			[&commandString](const ModConCommand* other) { return other->Name == commandString; });
+		if (res != mod.ConCommands.end())
+		{
+			found = *res;
+			break;
+		}
+	}
+	if (!found)
+		return;
+
+	switch (found->Context)
+	{
+	case ScriptContext::CLIENT:
+		ModConCommandCallback_Internal<ScriptContext::CLIENT>(found->Function, command);
+		break;
+	case ScriptContext::SERVER:
+		ModConCommandCallback_Internal<ScriptContext::SERVER>(found->Function, command);
+		break;
+	case ScriptContext::UI:
+		ModConCommandCallback_Internal<ScriptContext::UI>(found->Function, command);
+		break;
+	};
+}
+
+void ModManager::LoadMods()
+{
+	if (m_bHasLoadedMods)
+		UnloadMods();
+
+	std::vector<fs::path> modDirs;
+
+	// ensure dirs exist
+	fs::remove_all(GetCompiledAssetsPath());
+	fs::create_directories(GetModFolderPath());
+	fs::create_directories(GetThunderstoreModFolderPath());
+	fs::create_directories(GetRemoteModFolderPath());
+
+	m_DependencyConstants.clear();
+
+	// read enabled mods cfg
+	std::ifstream enabledModsStream(GetNorthstarPrefix() + "/enabledmods.json");
+	std::stringstream enabledModsStringStream;
+
+	if (!enabledModsStream.fail())
+	{
+		while (enabledModsStream.peek() != EOF)
+			enabledModsStringStream << (char)enabledModsStream.get();
+
+		enabledModsStream.close();
+		m_EnabledModsCfg.Parse<rapidjson::ParseFlag::kParseCommentsFlag | rapidjson::ParseFlag::kParseTrailingCommasFlag>(
+			enabledModsStringStream.str().c_str());
+
+		m_bHasEnabledModsCfg = m_EnabledModsCfg.IsObject();
+	}
+
+	// get mod directories
+	std::filesystem::directory_iterator classicModsDir = fs::directory_iterator(GetModFolderPath());
+	std::filesystem::directory_iterator remoteModsDir = fs::directory_iterator(GetRemoteModFolderPath());
+	std::filesystem::directory_iterator thunderstoreModsDir = fs::directory_iterator(GetThunderstoreModFolderPath());
+
+	for (fs::directory_entry dir : classicModsDir)
+		if (fs::exists(dir.path() / "mod.json"))
+			modDirs.push_back(dir.path());
+
+	// Special case for Thunderstore and remote mods directories
+	// Set up regex for `AUTHOR-MOD-VERSION` pattern
+	std::regex pattern(R"(.*\\([a-zA-Z0-9_]+)-([a-zA-Z0-9_]+)-(\d+\.\d+\.\d+))");
+
+	for (fs::directory_iterator dirIterator : {thunderstoreModsDir, remoteModsDir})
+	{
+		for (fs::directory_entry dir : dirIterator)
+		{
+			fs::path modsDir = dir.path() / "mods"; // Check for mods folder in the Thunderstore mod
+			// Use regex to match `AUTHOR-MOD-VERSION` pattern
+			if (!std::regex_match(dir.path().string(), pattern))
+			{
+				spdlog::warn("The following directory did not match 'AUTHOR-MOD-VERSION': {}", dir.path().string());
+				continue; // skip loading mod that doesn't match
+			}
+			if (fs::exists(modsDir) && fs::is_directory(modsDir))
+			{
+				for (fs::directory_entry subDir : fs::directory_iterator(modsDir))
+				{
+					if (fs::exists(subDir.path() / "mod.json"))
+					{
+						modDirs.push_back(subDir.path());
+					}
+				}
+			}
+		}
+	}
+
+	for (fs::path modDir : modDirs)
+	{
+		// read mod json file
+		std::ifstream jsonStream(modDir / "mod.json");
+		std::stringstream jsonStringStream;
+
+		// fail if no mod json
+		if (jsonStream.fail())
+		{
+			spdlog::warn(
+				"Mod file at '{}' does not exist or could not be read, is it installed correctly?", (modDir / "mod.json").string());
+			continue;
+		}
+
+		while (jsonStream.peek() != EOF)
+			jsonStringStream << (char)jsonStream.get();
+
+		jsonStream.close();
+
+		Mod mod(modDir, (char*)jsonStringStream.str().c_str());
+
+		for (auto& pair : mod.DependencyConstants)
+		{
+			if (m_DependencyConstants.find(pair.first) != m_DependencyConstants.end() && m_DependencyConstants[pair.first] != pair.second)
+			{
+				spdlog::error(
+					"'{}' attempted to register a dependency constant '{}' for '{}' that already exists for '{}'. "
+					"Change the constant name.",
+					mod.Name,
+					pair.first,
+					pair.second,
+					m_DependencyConstants[pair.first]);
+				mod.m_bWasReadSuccessfully = false;
+				break;
+			}
+			if (m_DependencyConstants.find(pair.first) == m_DependencyConstants.end())
+				m_DependencyConstants.emplace(pair);
+		}
+
+		for (std::string& dependency : mod.PluginDependencyConstants)
+		{
+			m_PluginDependencyConstants.insert(dependency);
+		}
+
+		if (m_bHasEnabledModsCfg && m_EnabledModsCfg.HasMember(mod.Name.c_str()))
+			mod.m_bEnabled = m_EnabledModsCfg[mod.Name.c_str()].IsTrue();
+		else
+			mod.m_bEnabled = true;
+
+		if (mod.m_bWasReadSuccessfully)
+		{
+			if (mod.m_bEnabled)
+				spdlog::info("'{}' loaded successfully, version {}", mod.Name, mod.Version);
+			else
+				spdlog::info("'{}' loaded successfully, version {} (DISABLED)", mod.Name, mod.Version);
+
+			m_LoadedMods.push_back(mod);
+		}
+		else
+			spdlog::warn("Mod file at '{}' failed to load", (modDir / "mod.json").string());
+	}
+
+	// sort by load prio, lowest-highest
+	std::sort(m_LoadedMods.begin(), m_LoadedMods.end(), [](Mod& a, Mod& b) { return a.LoadPriority < b.LoadPriority; });
+
+	// This is used to check if some mods have a folder but no entry in enabledmods.json
+	bool newModsDetected = false;
+
+	for (Mod& mod : m_LoadedMods)
+	{
+		if (!mod.m_bEnabled)
+			continue;
+
+		// Add mod entry to enabledmods.json if it doesn't exist
+		if (!mod.m_bIsRemote && !m_EnabledModsCfg.HasMember(mod.Name.c_str()))
+		{
+			m_EnabledModsCfg.AddMember(rapidjson_document::StringRefType(mod.Name.c_str()), true, m_EnabledModsCfg.GetAllocator());
+			newModsDetected = true;
+		}
+
+		// register convars
+		// for reloads, this is sorta barebones, when we have a good findconvar method, we could probably reset flags and stuff on
+		// preexisting convars note: we don't delete convars if they already exist because they're used for script stuff, unfortunately this
+		// causes us to leak memory on reload, but not much, potentially find a way to not do this at some point
+		for (ModConVar* convar : mod.ConVars)
+		{
+			// make sure convar isn't registered yet, unsure if necessary but idk what
+			// behaviour is for defining same convar multiple times
+			if (!g_pCVar->FindVar(convar->Name.c_str()))
+			{
+				new ConVar(convar->Name.c_str(), convar->DefaultValue.c_str(), convar->Flags, convar->HelpString.c_str());
+			}
+		}
+
+		for (ModConCommand* command : mod.ConCommands)
+		{
+			// make sure command isnt't registered multiple times.
+			if (!g_pCVar->FindCommand(command->Name.c_str()))
+			{
+				ConCommand* newCommand = new ConCommand();
+				std::string funcName = command->Function;
+				RegisterConCommand(command->Name.c_str(), ModConCommandCallback, command->HelpString.c_str(), command->Flags);
+			}
+		}
+
+		// read vpk paths
+		if (fs::exists(mod.m_ModDirectory / "vpk"))
+		{
+			// read vpk cfg
+			std::ifstream vpkJsonStream(mod.m_ModDirectory / "vpk/vpk.json");
+			std::stringstream vpkJsonStringStream;
+
+			bool bUseVPKJson = false;
+			rapidjson::Document dVpkJson;
+
+			if (!vpkJsonStream.fail())
+			{
+				while (vpkJsonStream.peek() != EOF)
+					vpkJsonStringStream << (char)vpkJsonStream.get();
+
+				vpkJsonStream.close();
+				dVpkJson.Parse<rapidjson::ParseFlag::kParseCommentsFlag | rapidjson::ParseFlag::kParseTrailingCommasFlag>(
+					vpkJsonStringStream.str().c_str());
+
+				bUseVPKJson = !dVpkJson.HasParseError() && dVpkJson.IsObject();
+			}
+
+			for (fs::directory_entry file : fs::directory_iterator(mod.m_ModDirectory / "vpk"))
+			{
+				// a bunch of checks to make sure we're only adding dir vpks and their paths are good
+				// note: the game will literally only load vpks with the english prefix
+				if (fs::is_regular_file(file) && file.path().extension() == ".vpk" &&
+					file.path().string().find("english") != std::string::npos &&
+					file.path().string().find(".bsp.pak000_dir") != std::string::npos)
+				{
+					std::string formattedPath = file.path().filename().string();
+
+					// this really fucking sucks but it'll work
+					std::string vpkName = formattedPath.substr(strlen("english"), formattedPath.find(".bsp") - 3);
+
+					ModVPKEntry& modVpk = mod.Vpks.emplace_back();
+					modVpk.m_bAutoLoad = !bUseVPKJson || (dVpkJson.HasMember("Preload") && dVpkJson["Preload"].IsObject() &&
+														  dVpkJson["Preload"].HasMember(vpkName) && dVpkJson["Preload"][vpkName].IsTrue());
+					modVpk.m_sVpkPath = (file.path().parent_path() / vpkName).string();
+
+					if (m_bHasLoadedMods && modVpk.m_bAutoLoad)
+						(*g_pFilesystem)->m_vtable->MountVPK(*g_pFilesystem, vpkName.c_str());
+				}
+			}
+		}
+
+		// read rpak paths
+		if (fs::exists(mod.m_ModDirectory / "paks"))
+		{
+			// read rpak cfg
+			std::ifstream rpakJsonStream(mod.m_ModDirectory / "paks/rpak.json");
+			std::stringstream rpakJsonStringStream;
+
+			bool bUseRpakJson = false;
+			rapidjson::Document dRpakJson;
+
+			if (!rpakJsonStream.fail())
+			{
+				while (rpakJsonStream.peek() != EOF)
+					rpakJsonStringStream << (char)rpakJsonStream.get();
+
+				rpakJsonStream.close();
+				dRpakJson.Parse<rapidjson::ParseFlag::kParseCommentsFlag | rapidjson::ParseFlag::kParseTrailingCommasFlag>(
+					rpakJsonStringStream.str().c_str());
+
+				bUseRpakJson = !dRpakJson.HasParseError() && dRpakJson.IsObject();
+			}
+
+			// read pak aliases
+			if (bUseRpakJson && dRpakJson.HasMember("Aliases") && dRpakJson["Aliases"].IsObject())
+			{
+				for (rapidjson::Value::ConstMemberIterator iterator = dRpakJson["Aliases"].MemberBegin();
+					 iterator != dRpakJson["Aliases"].MemberEnd();
+					 iterator++)
+				{
+					if (!iterator->name.IsString() || !iterator->value.IsString())
+						continue;
+
+					mod.RpakAliases.insert(std::make_pair(iterator->name.GetString(), iterator->value.GetString()));
+				}
+			}
+
+			for (fs::directory_entry file : fs::directory_iterator(mod.m_ModDirectory / "paks"))
+			{
+				// ensure we're only loading rpaks
+				if (fs::is_regular_file(file) && file.path().extension() == ".rpak")
+				{
+					std::string pakName(file.path().filename().string());
+
+					ModRpakEntry& modPak = mod.Rpaks.emplace_back();
+					modPak.m_bAutoLoad =
+						!bUseRpakJson || (dRpakJson.HasMember("Preload") && dRpakJson["Preload"].IsObject() &&
+										  dRpakJson["Preload"].HasMember(pakName) && dRpakJson["Preload"][pakName].IsTrue());
+
+					// postload things
+					if (!bUseRpakJson ||
+						(dRpakJson.HasMember("Postload") && dRpakJson["Postload"].IsObject() && dRpakJson["Postload"].HasMember(pakName)))
+						modPak.m_sLoadAfterPak = dRpakJson["Postload"][pakName].GetString();
+
+					modPak.m_sPakName = pakName;
+
+					// read header of file and get the starpak paths
+					// this is done here as opposed to on starpak load because multiple rpaks can load a starpak
+					// and there is seemingly no good way to tell which rpak is causing the load of a starpak :/
+
+					std::ifstream rpakStream(file.path(), std::ios::binary);
+
+					// seek to the point in the header where the starpak reference size is
+					rpakStream.seekg(0x38, std::ios::beg);
+					int starpaksSize = 0;
+					rpakStream.read((char*)&starpaksSize, 2);
+
+					// seek to just after the header
+					rpakStream.seekg(0x58, std::ios::beg);
+					// read the starpak reference(s)
+					std::vector<char> buf(starpaksSize);
+					rpakStream.read(buf.data(), starpaksSize);
+
+					rpakStream.close();
+
+					// split the starpak reference(s) into strings to hash
+					std::string str = "";
+					for (int i = 0; i < starpaksSize; i++)
+					{
+						// if the current char is null, that signals the end of the current starpak path
+						if (buf[i] != 0x00)
+						{
+							str += buf[i];
+						}
+						else
+						{
+							// only add the string we are making if it isnt empty
+							if (!str.empty())
+							{
+								mod.StarpakPaths.push_back(STR_HASH(str));
+								spdlog::info("Mod {} registered starpak '{}'", mod.Name, str);
+								str = "";
+							}
+						}
+					}
+
+					// not using atm because we need to resolve path to rpak
+					// if (m_hasLoadedMods && modPak.m_bAutoLoad)
+					//	g_pPakLoadManager->LoadPakAsync(pakName.c_str());
+				}
+			}
+		}
+
+		// read keyvalues paths
+		if (fs::exists(mod.m_ModDirectory / "keyvalues"))
+		{
+			for (fs::directory_entry file : fs::recursive_directory_iterator(mod.m_ModDirectory / "keyvalues"))
+			{
+				if (fs::is_regular_file(file))
+				{
+					std::string kvStr =
+						g_pModManager->NormaliseModFilePath(file.path().lexically_relative(mod.m_ModDirectory / "keyvalues"));
+					mod.KeyValues.emplace(STR_HASH(kvStr), kvStr);
+				}
+			}
+		}
+
+		// read pdiff
+		if (fs::exists(mod.m_ModDirectory / "mod.pdiff"))
+		{
+			std::ifstream pdiffStream(mod.m_ModDirectory / "mod.pdiff");
+
+			if (!pdiffStream.fail())
+			{
+				std::stringstream pdiffStringStream;
+				while (pdiffStream.peek() != EOF)
+					pdiffStringStream << (char)pdiffStream.get();
+
+				pdiffStream.close();
+
+				mod.Pdiff = pdiffStringStream.str();
+			}
+		}
+
+		// read bink video paths
+		if (fs::exists(mod.m_ModDirectory / "media"))
+		{
+			for (fs::directory_entry file : fs::recursive_directory_iterator(mod.m_ModDirectory / "media"))
+				if (fs::is_regular_file(file) && file.path().extension() == ".bik")
+					mod.BinkVideos.push_back(file.path().filename().string());
+		}
+
+		// try to load audio
+		if (fs::exists(mod.m_ModDirectory / "audio"))
+		{
+			for (fs::directory_entry file : fs::directory_iterator(mod.m_ModDirectory / "audio"))
+			{
+				if (fs::is_regular_file(file) && file.path().extension().string() == ".json")
+				{
+					if (!g_CustomAudioManager.TryLoadAudioOverride(file.path()))
+					{
+						spdlog::warn("Mod {} has an invalid audio def {}", mod.Name, file.path().filename().string());
+						continue;
+					}
+				}
+			}
+		}
+	}
+
+	// If there are new mods, we write entries accordingly in enabledmods.json
+	if (newModsDetected)
+	{
+		std::ofstream writeStream(GetNorthstarPrefix() + "/enabledmods.json");
+		rapidjson::OStreamWrapper writeStreamWrapper(writeStream);
+		rapidjson::PrettyWriter<rapidjson::OStreamWrapper> writer(writeStreamWrapper);
+		m_EnabledModsCfg.Accept(writer);
+	}
+
+	// in a seperate loop because we register mod files in reverse order, since mods loaded later should have their files prioritised
+	for (int64_t i = m_LoadedMods.size() - 1; i > -1; i--)
+	{
+		if (!m_LoadedMods[i].m_bEnabled)
+			continue;
+
+		if (fs::exists(m_LoadedMods[i].m_ModDirectory / MOD_OVERRIDE_DIR))
+		{
+			for (fs::directory_entry file : fs::recursive_directory_iterator(m_LoadedMods[i].m_ModDirectory / MOD_OVERRIDE_DIR))
+			{
+				std::string path =
+					g_pModManager->NormaliseModFilePath(file.path().lexically_relative(m_LoadedMods[i].m_ModDirectory / MOD_OVERRIDE_DIR));
+				if (file.is_regular_file() && m_ModFiles.find(path) == m_ModFiles.end())
+				{
+					ModOverrideFile modFile;
+					modFile.m_pOwningMod = &m_LoadedMods[i];
+					modFile.m_Path = path;
+					m_ModFiles.insert(std::make_pair(path, modFile));
+				}
+			}
+		}
+	}
+
+	// build modinfo obj for masterserver
+	rapidjson_document modinfoDoc;
+	auto& alloc = modinfoDoc.GetAllocator();
+	modinfoDoc.SetObject();
+	modinfoDoc.AddMember("Mods", rapidjson::kArrayType, alloc);
+
+	int currentModIndex = 0;
+	for (Mod& mod : m_LoadedMods)
+	{
+		if (!mod.m_bEnabled || (!mod.RequiredOnClient && !mod.Pdiff.size()))
+			continue;
+
+		modinfoDoc["Mods"].PushBack(rapidjson::kObjectType, modinfoDoc.GetAllocator());
+		modinfoDoc["Mods"][currentModIndex].AddMember("Name", rapidjson::StringRef(&mod.Name[0]), modinfoDoc.GetAllocator());
+		modinfoDoc["Mods"][currentModIndex].AddMember("Version", rapidjson::StringRef(&mod.Version[0]), modinfoDoc.GetAllocator());
+		modinfoDoc["Mods"][currentModIndex].AddMember("RequiredOnClient", mod.RequiredOnClient, modinfoDoc.GetAllocator());
+		modinfoDoc["Mods"][currentModIndex].AddMember("Pdiff", rapidjson::StringRef(&mod.Pdiff[0]), modinfoDoc.GetAllocator());
+
+		currentModIndex++;
+	}
+
+	rapidjson::StringBuffer buffer;
+	buffer.Clear();
+	rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
+	modinfoDoc.Accept(writer);
+	g_pMasterServerManager->m_sOwnModInfoJson = std::string(buffer.GetString());
+
+	m_bHasLoadedMods = true;
+}
+
+void ModManager::UnloadMods()
+{
+	// clean up stuff from mods before we unload
+	m_ModFiles.clear();
+	fs::remove_all(GetCompiledAssetsPath());
+
+	g_CustomAudioManager.ClearAudioOverrides();
+
+	if (!m_bHasEnabledModsCfg)
+		m_EnabledModsCfg.SetObject();
+
+	for (Mod& mod : m_LoadedMods)
+	{
+		// remove all built kvs
+		for (std::pair<size_t, std::string> kvPaths : mod.KeyValues)
+			fs::remove(GetCompiledAssetsPath() / fs::path(kvPaths.second).lexically_relative(mod.m_ModDirectory));
+
+		mod.KeyValues.clear();
+
+		// write to m_enabledModsCfg
+		// should we be doing this here or should scripts be doing this manually?
+		// main issue with doing this here is when we reload mods for connecting to a server, we write enabled mods, which isn't necessarily
+		// what we wanna do
+		if (!m_EnabledModsCfg.HasMember(mod.Name.c_str()))
+			m_EnabledModsCfg.AddMember(rapidjson_document::StringRefType(mod.Name.c_str()), false, m_EnabledModsCfg.GetAllocator());
+
+		m_EnabledModsCfg[mod.Name.c_str()].SetBool(mod.m_bEnabled);
+	}
+
+	std::ofstream writeStream(GetNorthstarPrefix() + "/enabledmods.json");
+	rapidjson::OStreamWrapper writeStreamWrapper(writeStream);
+	rapidjson::PrettyWriter<rapidjson::OStreamWrapper> writer(writeStreamWrapper);
+	m_EnabledModsCfg.Accept(writer);
+
+	// do we need to dealloc individual entries in m_loadedMods? idk, rework
+	m_LoadedMods.clear();
+}
+
+std::string ModManager::NormaliseModFilePath(const fs::path path)
+{
+	std::string str = path.lexically_normal().string();
+
+	// force to lowercase
+	for (char& c : str)
+		if (c <= 'Z' && c >= 'A')
+			c = c - ('Z' - 'z');
+
+	return str;
+}
+
+void ModManager::CompileAssetsForFile(const char* filename)
+{
+	size_t fileHash = STR_HASH(NormaliseModFilePath(fs::path(filename)));
+
+	if (fileHash == m_hScriptsRsonHash)
+		BuildScriptsRson();
+	else if (fileHash == m_hPdefHash)
+		BuildPdef();
+	else if (fileHash == m_hKBActHash)
+		BuildKBActionsList();
+	else
+	{
+		// check if we should build keyvalues, depending on whether any of our mods have patch kvs for this file
+		for (Mod& mod : m_LoadedMods)
+		{
+			if (!mod.m_bEnabled)
+				continue;
+
+			if (mod.KeyValues.find(fileHash) != mod.KeyValues.end())
+			{
+				TryBuildKeyValues(filename);
+				return;
+			}
+		}
+	}
+}
+
+void ConCommand_reload_mods(const CCommand& args)
+{
+	g_pModManager->LoadMods();
+}
+
+fs::path GetModFolderPath()
+{
+	return fs::path(GetNorthstarPrefix() + MOD_FOLDER_SUFFIX);
+}
+fs::path GetThunderstoreModFolderPath()
+{
+	return fs::path(GetNorthstarPrefix() + THUNDERSTORE_MOD_FOLDER_SUFFIX);
+}
+fs::path GetRemoteModFolderPath()
+{
+	return fs::path(GetNorthstarPrefix() + REMOTE_MOD_FOLDER_SUFFIX);
+}
+fs::path GetCompiledAssetsPath()
+{
+	return fs::path(GetNorthstarPrefix() + COMPILED_ASSETS_SUFFIX);
+}
+
+ON_DLL_LOAD_RELIESON("engine.dll", ModManager, (ConCommand, MasterServer), (CModule module))
+{
+	g_pModManager = new ModManager;
+
+	RegisterConCommand("reload_mods", ConCommand_reload_mods, "reloads mods", FCVAR_NONE);
+}
diff --git a/primedev/mods/modmanager.h b/primedev/mods/modmanager.h
new file mode 100644
index 00000000..233f004d
--- /dev/null
+++ b/primedev/mods/modmanager.h
@@ -0,0 +1,187 @@
+#pragma once
+#include "core/convar/convar.h"
+#include "core/memalloc.h"
+#include "squirrel/squirrel.h"
+
+#include "rapidjson/document.h"
+#include <string>
+#include <vector>
+#include <filesystem>
+#include <unordered_set>
+
+const std::string MOD_FOLDER_SUFFIX = "\\mods";
+const std::string THUNDERSTORE_MOD_FOLDER_SUFFIX = "\\packages";
+const std::string REMOTE_MOD_FOLDER_SUFFIX = "\\runtime\\remote\\mods";
+const fs::path MOD_OVERRIDE_DIR = "mod";
+const std::string COMPILED_ASSETS_SUFFIX = "\\runtime\\compiled";
+
+const std::set<std::string> MODS_BLACKLIST = {"Mod Settings"};
+
+struct ModConVar
+{
+public:
+	std::string Name;
+	std::string DefaultValue;
+	std::string HelpString;
+	int Flags;
+};
+
+struct ModConCommand
+{
+public:
+	std::string Name;
+	std::string Function;
+	std::string HelpString;
+	ScriptContext Context;
+	int Flags;
+};
+
+struct ModScriptCallback
+{
+public:
+	ScriptContext Context;
+
+	// called before the codecallback is executed
+	std::string BeforeCallback;
+	// called after the codecallback has finished executing
+	std::string AfterCallback;
+	// called right before the vm is destroyed.
+	std::string DestroyCallback;
+};
+
+struct ModScript
+{
+public:
+	std::string Path;
+	std::string RunOn;
+
+	std::vector<ModScriptCallback> Callbacks;
+};
+
+// these are pretty much identical, could refactor to use the same stuff?
+struct ModVPKEntry
+{
+public:
+	bool m_bAutoLoad;
+	std::string m_sVpkPath;
+};
+
+struct ModRpakEntry
+{
+public:
+	bool m_bAutoLoad;
+	std::string m_sPakName;
+	std::string m_sLoadAfterPak;
+};
+
+class Mod
+{
+public:
+	// runtime stuff
+	bool m_bEnabled = true;
+	bool m_bWasReadSuccessfully = false;
+	fs::path m_ModDirectory;
+	bool m_bIsRemote;
+
+	// mod.json stuff:
+
+	// the mod's name
+	std::string Name;
+	// the mod's description
+	std::string Description;
+	// the mod's version, should be in semver
+	std::string Version;
+	// a download link to the mod, for clients that try to join without the mod
+	std::string DownloadLink;
+
+	// whether clients need the mod to join servers running this mod
+	bool RequiredOnClient;
+	// the priority for this mod's files, mods with prio 0 are loaded first, then 1, then 2, etc
+	int LoadPriority;
+
+	// custom scripts used by the mod
+	std::vector<ModScript> Scripts;
+	// convars created by the mod
+	std::vector<ModConVar*> ConVars;
+	// concommands created by the mod
+	std::vector<ModConCommand*> ConCommands;
+	// custom localisation files created by the mod
+	std::vector<std::string> LocalisationFiles;
+	// custom script init.nut
+	std::string initScript;
+
+	// other files:
+
+	std::vector<ModVPKEntry> Vpks;
+	std::unordered_map<size_t, std::string> KeyValues;
+	std::vector<std::string> BinkVideos;
+	std::string Pdiff; // only need one per mod
+
+	std::vector<ModRpakEntry> Rpaks;
+	std::unordered_map<std::string, std::string>
+		RpakAliases; // paks we alias to other rpaks, e.g. to load sp_crashsite paks on the map mp_crashsite
+	std::vector<size_t> StarpakPaths; // starpaks that this mod contains
+	// there seems to be no nice way to get the rpak that is causing the load of a starpak?
+	// hashed with STR_HASH
+
+	std::unordered_map<std::string, std::string> DependencyConstants;
+	std::vector<std::string> PluginDependencyConstants;
+
+public:
+	Mod(fs::path modPath, char* jsonBuf);
+
+private:
+	void ParseConVars(rapidjson_document& json);
+	void ParseConCommands(rapidjson_document& json);
+	void ParseScripts(rapidjson_document& json);
+	void ParseLocalization(rapidjson_document& json);
+	void ParseDependencies(rapidjson_document& json);
+	void ParsePluginDependencies(rapidjson_document& json);
+	void ParseInitScript(rapidjson_document& json);
+};
+
+struct ModOverrideFile
+{
+public:
+	Mod* m_pOwningMod;
+	fs::path m_Path;
+};
+
+class ModManager
+{
+private:
+	bool m_bHasLoadedMods = false;
+	bool m_bHasEnabledModsCfg;
+	rapidjson_document m_EnabledModsCfg;
+
+	// precalculated hashes
+	size_t m_hScriptsRsonHash;
+	size_t m_hPdefHash;
+	size_t m_hKBActHash;
+
+public:
+	std::vector<Mod> m_LoadedMods;
+	std::unordered_map<std::string, ModOverrideFile> m_ModFiles;
+	std::unordered_map<std::string, std::string> m_DependencyConstants;
+	std::unordered_set<std::string> m_PluginDependencyConstants;
+
+public:
+	ModManager();
+	void LoadMods();
+	void UnloadMods();
+	std::string NormaliseModFilePath(const fs::path path);
+	void CompileAssetsForFile(const char* filename);
+
+	// compile asset type stuff, these are done in files under runtime/compiled/
+	void BuildScriptsRson();
+	void TryBuildKeyValues(const char* filename);
+	void BuildPdef();
+	void BuildKBActionsList();
+};
+
+fs::path GetModFolderPath();
+fs::path GetRemoteModFolderPath();
+fs::path GetThunderstoreModFolderPath();
+fs::path GetCompiledAssetsPath();
+
+extern ModManager* g_pModManager;
diff --git a/primedev/mods/modsavefiles.cpp b/primedev/mods/modsavefiles.cpp
new file mode 100644
index 00000000..68e33864
--- /dev/null
+++ b/primedev/mods/modsavefiles.cpp
@@ -0,0 +1,572 @@
+#include <filesystem>
+#include <sstream>
+#include <fstream>
+#include "squirrel/squirrel.h"
+#include "util/utils.h"
+#include "mods/modmanager.h"
+#include "modsavefiles.h"
+#include "rapidjson/document.h"
+#include "rapidjson/writer.h"
+#include "rapidjson/stringbuffer.h"
+#include "config/profile.h"
+#include "core/tier0.h"
+#include "rapidjson/error/en.h"
+#include "scripts/scriptjson.h"
+
+SaveFileManager* g_pSaveFileManager;
+int MAX_FOLDER_SIZE = 52428800; // 50MB (50 * 1024 * 1024)
+fs::path savePath;
+
+/// <summary></summary>
+/// <param name="dir">The directory we want the size of.</param>
+/// <param name="file">The file we're excluding from the calculation.</param>
+/// <returns>The size of the contents of the current directory, excluding a specific file.</returns>
+uintmax_t GetSizeOfFolderContentsMinusFile(fs::path dir, std::string file)
+{
+	uintmax_t result = 0;
+	for (const auto& entry : fs::directory_iterator(dir))
+	{
+		if (entry.path().filename() == file)
+			continue;
+		// fs::file_size may not work on directories - but does in some cases.
+		// per cppreference.com, it's "implementation-defined".
+		try
+		{
+			result += fs::file_size(entry.path());
+		}
+		catch (fs::filesystem_error& e)
+		{
+			if (entry.is_directory())
+			{
+				result += GetSizeOfFolderContentsMinusFile(entry.path(), "");
+			}
+		}
+	}
+	return result;
+}
+
+uintmax_t GetSizeOfFolder(fs::path dir)
+{
+	uintmax_t result = 0;
+	for (const auto& entry : fs::directory_iterator(dir))
+	{
+		// fs::file_size may not work on directories - but does in some cases.
+		// per cppreference.com, it's "implementation-defined".
+		try
+		{
+			result += fs::file_size(entry.path());
+		}
+		catch (fs::filesystem_error& e)
+		{
+			if (entry.is_directory())
+			{
+				result += GetSizeOfFolderContentsMinusFile(entry.path(), "");
+			}
+		}
+	}
+	return result;
+}
+
+// Saves a file asynchronously.
+template <ScriptContext context> void SaveFileManager::SaveFileAsync(fs::path file, std::string contents)
+{
+	auto mutex = std::ref(fileMutex);
+	std::thread writeThread(
+		[mutex, file, contents]()
+		{
+			try
+			{
+				mutex.get().lock();
+
+				fs::path dir = file.parent_path();
+				// this actually allows mods to go over the limit, but not by much
+				// the limit is to prevent mods from taking gigabytes of space,
+				// we don't need to be particularly strict.
+				if (GetSizeOfFolderContentsMinusFile(dir, file.filename().string()) + contents.length() > MAX_FOLDER_SIZE)
+				{
+					// tbh, you're either trying to fill the hard drive or use so much data, you SHOULD be congratulated.
+					spdlog::error(fmt::format("Mod spamming save requests? Folder limit bypassed despite previous checks. Not saving."));
+					mutex.get().unlock();
+					return;
+				}
+
+				std::ofstream fileStr(file);
+				if (fileStr.fail())
+				{
+					mutex.get().unlock();
+					return;
+				}
+
+				fileStr.write(contents.c_str(), contents.length());
+				fileStr.close();
+
+				mutex.get().unlock();
+				// side-note: this causes a leak?
+				// when a file is added to the map, it's never removed.
+				// no idea how to fix this - because we have no way to check if there are other threads waiting to use this file(?)
+				// tried to use m.try_lock(), but it's unreliable, it seems.
+			}
+			catch (std::exception ex)
+			{
+				spdlog::error("SAVE FAILED!");
+				mutex.get().unlock();
+				spdlog::error(ex.what());
+			}
+		});
+
+	writeThread.detach();
+}
+
+// Loads a file asynchronously.
+template <ScriptContext context> int SaveFileManager::LoadFileAsync(fs::path file)
+{
+	int handle = ++m_iLastRequestHandle;
+	auto mutex = std::ref(fileMutex);
+	std::thread readThread(
+		[mutex, file, handle]()
+		{
+			try
+			{
+				mutex.get().lock();
+
+				std::ifstream fileStr(file);
+				if (fileStr.fail())
+				{
+					spdlog::error("A file was supposed to be loaded but we can't access it?!");
+
+					g_pSquirrel<context>->AsyncCall("NSHandleLoadResult", handle, false, "");
+					mutex.get().unlock();
+					return;
+				}
+
+				std::stringstream stringStream;
+				stringStream << fileStr.rdbuf();
+
+				g_pSquirrel<context>->AsyncCall("NSHandleLoadResult", handle, true, stringStream.str());
+
+				fileStr.close();
+				mutex.get().unlock();
+				// side-note: this causes a leak?
+				// when a file is added to the map, it's never removed.
+				// no idea how to fix this - because we have no way to check if there are other threads waiting to use this file(?)
+				// tried to use m.try_lock(), but it's unreliable, it seems.
+			}
+			catch (std::exception ex)
+			{
+				spdlog::error("LOAD FAILED!");
+				g_pSquirrel<context>->AsyncCall("NSHandleLoadResult", handle, false, "");
+				mutex.get().unlock();
+				spdlog::error(ex.what());
+			}
+		});
+
+	readThread.detach();
+	return handle;
+}
+
+// Deletes a file asynchronously.
+template <ScriptContext context> void SaveFileManager::DeleteFileAsync(fs::path file)
+{
+	// P.S. I don't like how we have to async delete calls but we do.
+	auto m = std::ref(fileMutex);
+	std::thread deleteThread(
+		[m, file]()
+		{
+			try
+			{
+				m.get().lock();
+
+				fs::remove(file);
+
+				m.get().unlock();
+				// side-note: this causes a leak?
+				// when a file is added to the map, it's never removed.
+				// no idea how to fix this - because we have no way to check if there are other threads waiting to use this file(?)
+				// tried to use m.try_lock(), but it's unreliable, it seems.
+			}
+			catch (std::exception ex)
+			{
+				spdlog::error("DELETE FAILED!");
+				m.get().unlock();
+				spdlog::error(ex.what());
+			}
+		});
+
+	deleteThread.detach();
+}
+
+// Checks if a file contains null characters.
+bool ContainsInvalidChars(std::string str)
+{
+	// we don't allow null characters either, even if they're ASCII characters because idk if people can
+	// use it to circumvent the file extension suffix.
+	return std::any_of(str.begin(), str.end(), [](char c) { return c == '\0'; });
+}
+
+// Checks if the relative path (param) remains inside the mod directory (dir).
+// Paths are restricted to ASCII because encoding is fucked and we decided we won't bother.
+bool IsPathSafe(const std::string param, fs::path dir)
+{
+	try
+	{
+		auto const normRoot = fs::weakly_canonical(dir);
+		auto const normChild = fs::weakly_canonical(dir / param);
+
+		auto itr = std::search(normChild.begin(), normChild.end(), normRoot.begin(), normRoot.end());
+		// we return if the file is safe (inside the directory) and uses only ASCII chars in the path.
+		return itr == normChild.begin() && std::none_of(
+											   param.begin(),
+											   param.end(),
+											   [](char c)
+											   {
+												   unsigned char unsignedC = static_cast<unsigned char>(c);
+												   return unsignedC > 127 || unsignedC < 0;
+											   });
+	}
+	catch (fs::filesystem_error err)
+	{
+		return false;
+	}
+}
+
+// void NSSaveFile( string file, string data )
+ADD_SQFUNC("void", NSSaveFile, "string file, string data", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm);
+	if (mod == nullptr)
+	{
+		g_pSquirrel<context>->raiseerror(sqvm, "Has to be called from a mod function!");
+		return SQRESULT_ERROR;
+	}
+
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string fileName = g_pSquirrel<context>->getstring(sqvm, 1);
+	if (!IsPathSafe(fileName, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				fileName,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+
+	std::string content = g_pSquirrel<context>->getstring(sqvm, 2);
+	if (ContainsInvalidChars(content))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm, fmt::format("File contents may not contain NUL/\\0 characters! Make sure your strings are valid!", mod->Name).c_str());
+		return SQRESULT_ERROR;
+	}
+
+	fs::create_directories(dir);
+	// this actually allows mods to go over the limit, but not by much
+	// the limit is to prevent mods from taking gigabytes of space,
+	// this ain't a cloud service.
+	if (GetSizeOfFolderContentsMinusFile(dir, fileName) + content.length() > MAX_FOLDER_SIZE)
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"The mod {} has reached the maximum folder size.\n\nAsk the mod developer to optimize their data usage,"
+				"or increase the maximum folder size using the -maxfoldersize launch parameter.",
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+
+	g_pSaveFileManager->SaveFileAsync<context>(dir / fileName, content);
+
+	return SQRESULT_NULL;
+}
+
+// void NSSaveJSONFile(string file, table data)
+ADD_SQFUNC("void", NSSaveJSONFile, "string file, table data", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm);
+	if (mod == nullptr)
+	{
+		g_pSquirrel<context>->raiseerror(sqvm, "Has to be called from a mod function!");
+		return SQRESULT_ERROR;
+	}
+
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string fileName = g_pSquirrel<context>->getstring(sqvm, 1);
+	if (!IsPathSafe(fileName, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				fileName,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+
+	// Note - this cannot be done in the async func since the table may get garbage collected.
+	// This means that especially large tables may still clog up the system.
+	std::string content = EncodeJSON<context>(sqvm);
+	if (ContainsInvalidChars(content))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm, fmt::format("File contents may not contain NUL/\\0 characters! Make sure your strings are valid!", mod->Name).c_str());
+		return SQRESULT_ERROR;
+	}
+
+	fs::create_directories(dir);
+	// this actually allows mods to go over the limit, but not by much
+	// the limit is to prevent mods from taking gigabytes of space,
+	// this ain't a cloud service.
+	if (GetSizeOfFolderContentsMinusFile(dir, fileName) + content.length() > MAX_FOLDER_SIZE)
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"The mod {} has reached the maximum folder size.\n\nAsk the mod developer to optimize their data usage,"
+				"or increase the maximum folder size using the -maxfoldersize launch parameter.",
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+
+	g_pSaveFileManager->SaveFileAsync<context>(dir / fileName, content);
+
+	return SQRESULT_NULL;
+}
+
+// int NS_InternalLoadFile(string file)
+ADD_SQFUNC("int", NS_InternalLoadFile, "string file", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm, 1); // the function that called NSLoadFile :)
+	if (mod == nullptr)
+	{
+		g_pSquirrel<context>->raiseerror(sqvm, "Has to be called from a mod function!");
+		return SQRESULT_ERROR;
+	}
+
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string fileName = g_pSquirrel<context>->getstring(sqvm, 1);
+	if (!IsPathSafe(fileName, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				fileName,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+
+	g_pSquirrel<context>->pushinteger(sqvm, g_pSaveFileManager->LoadFileAsync<context>(dir / fileName));
+
+	return SQRESULT_NOTNULL;
+}
+
+// bool NSDoesFileExist(string file)
+ADD_SQFUNC("bool", NSDoesFileExist, "string file", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm);
+
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string fileName = g_pSquirrel<context>->getstring(sqvm, 1);
+	if (!IsPathSafe(fileName, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				fileName,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+
+	g_pSquirrel<context>->pushbool(sqvm, fs::exists(dir / (fileName)));
+	return SQRESULT_NOTNULL;
+}
+
+// int NSGetFileSize(string file)
+ADD_SQFUNC("int", NSGetFileSize, "string file", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm);
+
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string fileName = g_pSquirrel<context>->getstring(sqvm, 1);
+	if (!IsPathSafe(fileName, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				fileName,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+	try
+	{
+		// throws if file does not exist
+		// we don't want stuff such as "file does not exist, file is unavailable" to be lethal, so we just try/catch fs errors
+		g_pSquirrel<context>->pushinteger(sqvm, (int)(fs::file_size(dir / fileName) / 1024));
+	}
+	catch (std::filesystem::filesystem_error const& ex)
+	{
+		spdlog::error("GET FILE SIZE FAILED! Is the path valid?");
+		g_pSquirrel<context>->raiseerror(sqvm, ex.what());
+		return SQRESULT_ERROR;
+	}
+	return SQRESULT_NOTNULL;
+}
+
+// void NSDeleteFile(string file)
+ADD_SQFUNC("void", NSDeleteFile, "string file", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm);
+
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string fileName = g_pSquirrel<context>->getstring(sqvm, 1);
+	if (!IsPathSafe(fileName, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				fileName,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+
+	g_pSaveFileManager->DeleteFileAsync<context>(dir / fileName);
+	return SQRESULT_NOTNULL;
+}
+
+// The param is not optional because that causes issues :)
+ADD_SQFUNC("array<string>", NS_InternalGetAllFiles, "string path", "", ScriptContext::CLIENT | ScriptContext::UI | ScriptContext::SERVER)
+{
+	// depth 1 because this should always get called from Northstar.Custom
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm, 1);
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string pathStr = g_pSquirrel<context>->getstring(sqvm, 1);
+	fs::path path = dir;
+	if (pathStr != "")
+		path = dir / pathStr;
+	if (!IsPathSafe(pathStr, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				pathStr,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+	try
+	{
+		g_pSquirrel<context>->newarray(sqvm, 0);
+		for (const auto& entry : fs::directory_iterator(path))
+		{
+			g_pSquirrel<context>->pushstring(sqvm, entry.path().filename().string().c_str());
+			g_pSquirrel<context>->arrayappend(sqvm, -2);
+		}
+		return SQRESULT_NOTNULL;
+	}
+	catch (std::exception ex)
+	{
+		spdlog::error("DIR ITERATE FAILED! Is the path valid?");
+		g_pSquirrel<context>->raiseerror(sqvm, ex.what());
+		return SQRESULT_ERROR;
+	}
+}
+
+ADD_SQFUNC("bool", NSIsFolder, "string path", "", ScriptContext::CLIENT | ScriptContext::UI | ScriptContext::SERVER)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm);
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	std::string pathStr = g_pSquirrel<context>->getstring(sqvm, 1);
+	fs::path path = dir;
+	if (pathStr != "")
+		path = dir / pathStr;
+	if (!IsPathSafe(pathStr, dir))
+	{
+		g_pSquirrel<context>->raiseerror(
+			sqvm,
+			fmt::format(
+				"File name invalid ({})! Make sure it does not contain any non-ASCII character, and results in a path inside your mod's "
+				"save folder.",
+				pathStr,
+				mod->Name)
+				.c_str());
+		return SQRESULT_ERROR;
+	}
+	try
+	{
+		g_pSquirrel<context>->pushbool(sqvm, fs::is_directory(path));
+		return SQRESULT_NOTNULL;
+	}
+	catch (std::exception ex)
+	{
+		spdlog::error("DIR READ FAILED! Is the path valid?");
+		spdlog::info(path.string());
+		g_pSquirrel<context>->raiseerror(sqvm, ex.what());
+		return SQRESULT_ERROR;
+	}
+}
+
+// side note, expensive.
+ADD_SQFUNC("int", NSGetTotalSpaceRemaining, "", "", ScriptContext::CLIENT | ScriptContext::UI | ScriptContext::SERVER)
+{
+	Mod* mod = g_pSquirrel<context>->getcallingmod(sqvm);
+	fs::path dir = savePath / fs::path(mod->m_ModDirectory).filename();
+	g_pSquirrel<context>->pushinteger(sqvm, (MAX_FOLDER_SIZE - GetSizeOfFolder(dir)) / 1024);
+	return SQRESULT_NOTNULL;
+}
+
+// ok, I'm just gonna explain what the fuck is going on here because this
+// is the pinnacle of my stupidity and I do not want to touch this ever
+// again, yet someone will eventually have to maintain this.
+template <ScriptContext context> std::string EncodeJSON(HSquirrelVM* sqvm)
+{
+	// new rapidjson
+	rapidjson_document doc;
+	doc.SetObject();
+
+	// get the SECOND param
+	SQTable* table = sqvm->_stackOfCurrentFunction[2]._VAL.asTable;
+	// take the table and copy it's contents over into the rapidjson_document
+	EncodeJSONTable<context>(table, &doc, doc.GetAllocator());
+
+	// convert JSON document to string
+	rapidjson::StringBuffer buffer;
+	rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
+	doc.Accept(writer);
+
+	// return the converted string
+	return buffer.GetString();
+}
+
+ON_DLL_LOAD("engine.dll", ModSaveFFiles_Init, (CModule module))
+{
+	savePath = fs::path(GetNorthstarPrefix()) / "save_data";
+	g_pSaveFileManager = new SaveFileManager;
+	int parm = CommandLine()->FindParm("-maxfoldersize");
+	if (parm)
+		MAX_FOLDER_SIZE = std::stoi(CommandLine()->GetParm(parm));
+}
+
+int GetMaxSaveFolderSize()
+{
+	return MAX_FOLDER_SIZE;
+}
diff --git a/primedev/mods/modsavefiles.h b/primedev/mods/modsavefiles.h
new file mode 100644
index 00000000..f9d39723
--- /dev/null
+++ b/primedev/mods/modsavefiles.h
@@ -0,0 +1,16 @@
+#pragma once
+int GetMaxSaveFolderSize();
+bool ContainsInvalidChars(std::string str);
+
+class SaveFileManager
+{
+public:
+	template <ScriptContext context> void SaveFileAsync(fs::path file, std::string content);
+	template <ScriptContext context> int LoadFileAsync(fs::path file);
+	template <ScriptContext context> void DeleteFileAsync(fs::path file);
+	// Future proofed in that if we ever get multi-threaded SSDs this code will take advantage of them.
+	std::mutex fileMutex;
+
+private:
+	int m_iLastRequestHandle = 0;
+};