1 files changed, 177 insertions, 0 deletions
diff --git a/primedev/core/filesystem/filesystem.cpp b/primedev/core/filesystem/filesystem.cpp
new file mode 100644
index 00000000..b39939e4
--- /dev/null
+++ b/primedev/core/filesystem/filesystem.cpp
@@ -0,0 +1,177 @@
+#include "filesystem.h"
+#include "core/sourceinterface.h"
+#include "mods/modmanager.h"
+
+#include <iostream>
+#include <sstream>
+
+AUTOHOOK_INIT()
+
+bool bReadingOriginalFile = false;
+std::string sCurrentModPath;
+
+ConVar* Cvar_ns_fs_log_reads;
+
+SourceInterface<IFileSystem>* g_pFilesystem;
+
+std::string ReadVPKFile(const char* path)
+{
+	// read scripts.rson file, todo: check if this can be overwritten
+	FileHandle_t fileHandle = (*g_pFilesystem)->m_vtable2->Open(&(*g_pFilesystem)->m_vtable2, path, "rb", "GAME", 0);
+
+	std::stringstream fileStream;
+	int bytesRead = 0;
+	char data[4096];
+	do
+	{
+		bytesRead = (*g_pFilesystem)->m_vtable2->Read(&(*g_pFilesystem)->m_vtable2, data, (int)std::size(data), fileHandle);
+		fileStream.write(data, bytesRead);
+	} while (bytesRead == std::size(data));
+
+	(*g_pFilesystem)->m_vtable2->Close(*g_pFilesystem, fileHandle);
+
+	return fileStream.str();
+}
+
+std::string ReadVPKOriginalFile(const char* path)
+{
+	// todo: should probably set search path to be g_pModName here also
+
+	bReadingOriginalFile = true;
+	std::string ret = ReadVPKFile(path);
+	bReadingOriginalFile = false;
+
+	return ret;
+}
+
+// clang-format off
+HOOK(AddSearchPathHook, AddSearchPath,
+void, __fastcall, (IFileSystem * fileSystem, const char* pPath, const char* pathID, SearchPathAdd_t addType))
+// clang-format on
+{
+	AddSearchPath(fileSystem, pPath, pathID, addType);
+
+	// make sure current mod paths are at head
+	if (!strcmp(pathID, "GAME") && sCurrentModPath.compare(pPath) && addType == PATH_ADD_TO_HEAD)
+	{
+		AddSearchPath(fileSystem, sCurrentModPath.c_str(), "GAME", PATH_ADD_TO_HEAD);
+		AddSearchPath(fileSystem, GetCompiledAssetsPath().string().c_str(), "GAME", PATH_ADD_TO_HEAD);
+	}
+}
+
+void SetNewModSearchPaths(Mod* mod)
+{
+	// put our new path to the head if we need to read from a different mod path
+	// in the future we could also determine whether the file we're setting paths for needs a mod dir, or compiled assets
+	if (mod != nullptr)
+	{
+		if ((fs::absolute(mod->m_ModDirectory) / MOD_OVERRIDE_DIR).string().compare(sCurrentModPath))
+		{
+			AddSearchPath(
+				&*(*g_pFilesystem), (fs::absolute(mod->m_ModDirectory) / MOD_OVERRIDE_DIR).string().c_str(), "GAME", PATH_ADD_TO_HEAD);
+			sCurrentModPath = (fs::absolute(mod->m_ModDirectory) / MOD_OVERRIDE_DIR).string();
+		}
+	}
+	else // push compiled to head
+		AddSearchPath(&*(*g_pFilesystem), fs::absolute(GetCompiledAssetsPath()).string().c_str(), "GAME", PATH_ADD_TO_HEAD);
+}
+
+bool TryReplaceFile(const char* pPath, bool shouldCompile)
+{
+	if (bReadingOriginalFile)
+		return false;
+
+	if (shouldCompile)
+		g_pModManager->CompileAssetsForFile(pPath);
+
+	// idk how efficient the lexically normal check is
+	// can't just set all /s in path to \, since some paths aren't in writeable memory
+	auto file = g_pModManager->m_ModFiles.find(g_pModManager->NormaliseModFilePath(fs::path(pPath)));
+	if (file != g_pModManager->m_ModFiles.end())
+	{
+		SetNewModSearchPaths(file->second.m_pOwningMod);
+		return true;
+	}
+
+	return false;
+}
+
+// force modded files to be read from mods, not cache
+// clang-format off
+HOOK(ReadFromCacheHook, ReadFromCache,
+bool, __fastcall, (IFileSystem * filesystem, char* pPath, void* result))
+// clang-format off
+{
+	if (TryReplaceFile(pPath, true))
+		return false;
+
+	return ReadFromCache(filesystem, pPath, result);
+}
+
+// force modded files to be read from mods, not vpk
+// clang-format off
+AUTOHOOK(ReadFileFromVPK, filesystem_stdio.dll + 0x5CBA0,
+FileHandle_t, __fastcall, (VPKData* vpkInfo, uint64_t* b, char* filename))
+// clang-format on
+{
+	// don't compile here because this is only ever called from OpenEx, which already compiles
+	if (TryReplaceFile(filename, false))
+	{
+		*b = -1;
+		return b;
+	}
+
+	return ReadFileFromVPK(vpkInfo, b, filename);
+}
+
+// clang-format off
+AUTOHOOK(CBaseFileSystem__OpenEx, filesystem_stdio.dll + 0x15F50,
+FileHandle_t, __fastcall, (IFileSystem* filesystem, const char* pPath, const char* pOptions, uint32_t flags, const char* pPathID, char **ppszResolvedFilename))
+// clang-format on
+{
+	TryReplaceFile(pPath, true);
+	return CBaseFileSystem__OpenEx(filesystem, pPath, pOptions, flags, pPathID, ppszResolvedFilename);
+}
+
+HOOK(MountVPKHook, MountVPK, VPKData*, , (IFileSystem * fileSystem, const char* pVpkPath))
+{
+	NS::log::fs->info("MountVPK {}", pVpkPath);
+	VPKData* ret = MountVPK(fileSystem, pVpkPath);
+
+	for (Mod mod : g_pModManager->m_LoadedMods)
+	{
+		if (!mod.m_bEnabled)
+			continue;
+
+		for (ModVPKEntry& vpkEntry : mod.Vpks)
+		{
+			// if we're autoloading, just load no matter what
+			if (!vpkEntry.m_bAutoLoad)
+			{
+				// resolve vpk name and try to load one with the same name
+				// todo: we should be unloading these on map unload manually
+				std::string mapName(fs::path(pVpkPath).filename().string());
+				std::string modMapName(fs::path(vpkEntry.m_sVpkPath.c_str()).filename().string());
+				if (mapName.compare(modMapName))
+					continue;
+			}
+
+			VPKData* loaded = MountVPK(fileSystem, vpkEntry.m_sVpkPath.c_str());
+			if (!ret) // this is primarily for map vpks and stuff, so the map's vpk is what gets returned from here
+				ret = loaded;
+		}
+	}
+
+	return ret;
+}
+
+ON_DLL_LOAD("filesystem_stdio.dll", Filesystem, (CModule module))
+{
+	AUTOHOOK_DISPATCH()
+
+	g_pFilesystem = new SourceInterface<IFileSystem>("filesystem_stdio.dll", "VFileSystem017");
+
+	AddSearchPathHook.Dispatch((LPVOID)(*g_pFilesystem)->m_vtable->AddSearchPath);
+	ReadFromCacheHook.Dispatch((LPVOID)(*g_pFilesystem)->m_vtable->ReadFromCache);
+	MountVPKHook.Dispatch((LPVOID)(*g_pFilesystem)->m_vtable->MountVPK);
+}