#include "pch.h"
#include <stdio.h>
#include <string>
#include <system_error>
#include <shlwapi.h>
#include <sstream>
#include <fstream>
#include <filesystem>

HMODULE hLauncherModule;
HMODULE hHookModule;
HMODULE hTier0Module;

using CreateInterfaceFn = void* (*)(const char* pName, int* pReturnCode);

// does not seem to ever be used
extern "C" __declspec(dllexport) void* __fastcall CreateInterface(const char* pName, int* pReturnCode)
{
	// AppSystemCreateInterfaceFn(pName, pReturnCode);
	printf("external CreateInterface: name: %s\n", pName);

	static CreateInterfaceFn launcher_CreateInterface = (CreateInterfaceFn)GetProcAddress(hLauncherModule, "CreateInterface");
	auto res = launcher_CreateInterface(pName, pReturnCode);

	printf("external CreateInterface: return code: %p\n", res);
	return res;
}

bool GetExePathWide(wchar_t* dest, DWORD destSize)
{
	if (!dest)
		return NULL;
	if (destSize < MAX_PATH)
		return NULL;

	DWORD length = GetModuleFileNameW(NULL, dest, destSize);
	return length && PathRemoveFileSpecW(dest);
}

FARPROC GetLauncherMain()
{
	static FARPROC Launcher_LauncherMain;
	if (!Launcher_LauncherMain)
		Launcher_LauncherMain = GetProcAddress(hLauncherModule, "LauncherMain");
	return Launcher_LauncherMain;
}

void LibraryLoadError(DWORD dwMessageId, const wchar_t* libName, const wchar_t* location)
{
	char text[4096];
	std::string message = std::system_category().message(dwMessageId);
	sprintf_s(text, "Failed to load the %ls at \"%ls\" (%lu):\n\n%hs", libName, location, dwMessageId, message.c_str());
	if (dwMessageId == 126 && std::filesystem::exists(location))
	{
		sprintf_s(
			text,
			"%s\n\nThe file at the specified location DOES exist, so this error indicates that one of its *dependencies* failed to be "
			"found.",
			text);
	}
	MessageBoxA(GetForegroundWindow(), text, "Northstar Launcher Proxy Error", 0);
}

BOOL APIENTRY DllMain(HMODULE hModule, DWORD ul_reason_for_call, LPVOID lpReserved)
{
	switch (ul_reason_for_call)
	{
	case DLL_PROCESS_ATTACH:
	case DLL_THREAD_ATTACH:
	case DLL_THREAD_DETACH:
	case DLL_PROCESS_DETACH:
		break;
	}
	return TRUE;
}

wchar_t exePath[4096];
wchar_t dllPath[4096];

bool ShouldLoadNorthstar()
{
	bool loadNorthstar = !strstr(GetCommandLineA(), "-vanilla");

	if (!loadNorthstar)
		return loadNorthstar;

	auto runNorthstarFile = std::ifstream("run_northstar.txt");
	if (runNorthstarFile)
	{
		std::stringstream runNorthstarFileBuffer;
		runNorthstarFileBuffer << runNorthstarFile.rdbuf();
		runNorthstarFile.close();
		if (runNorthstarFileBuffer.str().starts_with("0"))
			loadNorthstar = false;
	}
	return loadNorthstar;
}

bool LoadNorthstar()
{
	FARPROC Hook_Init = nullptr;
	{
		swprintf_s(dllPath, L"%s\\Northstar.dll", exePath);
		hHookModule = LoadLibraryExW(dllPath, 0, LOAD_WITH_ALTERED_SEARCH_PATH);
		if (hHookModule)
			Hook_Init = GetProcAddress(hHookModule, "InitialiseNorthstar");
		if (!hHookModule || Hook_Init == nullptr)
		{
			LibraryLoadError(GetLastError(), L"Northstar.dll", dllPath);
			return false;
		}
	}

	((bool (*)())Hook_Init)();
	return true;
}

extern "C" __declspec(dllexport) int LauncherMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
	{
		if (!GetExePathWide(exePath, 4096))
		{
			MessageBoxA(
				GetForegroundWindow(),
				"Failed getting game directory.\nThe game cannot continue and has to exit.",
				"Northstar Launcher Proxy Error",
				0);
			return 1;
		}

		SetCurrentDirectoryW(exePath);

		bool loadNorthstar = ShouldLoadNorthstar();

		if (loadNorthstar)
		{
			swprintf_s(dllPath, L"%s\\bin\\x64_retail\\tier0.dll", exePath);
			hTier0Module = LoadLibraryExW(dllPath, 0, LOAD_WITH_ALTERED_SEARCH_PATH);
			if (!hTier0Module)
			{
				LibraryLoadError(GetLastError(), L"tier0.dll", dllPath);
				return 1;
			}

			if (!LoadNorthstar())
				return 1;
		}
		// else printf("\n\n WILL !!!NOT!!! LOAD NORTHSTAR\n\n");

		swprintf_s(dllPath, L"%s\\bin\\x64_retail\\launcher.org.dll", exePath);
		hLauncherModule = LoadLibraryExW(dllPath, 0, LOAD_WITH_ALTERED_SEARCH_PATH);
		if (!hLauncherModule)
		{
			LibraryLoadError(GetLastError(), L"launcher.org.dll", dllPath);
			return 1;
		}
	}

	auto LauncherMain = GetLauncherMain();
	if (!LauncherMain)
		MessageBoxA(
			GetForegroundWindow(),
			"Failed loading launcher.org.dll.\nThe game cannot continue and has to exit.",
			"Northstar Launcher Proxy Error",
			0);
	// auto result = ((__int64(__fastcall*)())LauncherMain)();
	// auto result = ((signed __int64(__fastcall*)(__int64))LauncherMain)(0i64);
	return ((int(__fastcall*)(HINSTANCE, HINSTANCE, LPSTR, int))LauncherMain)(hInstance, hPrevInstance, lpCmdLine, nCmdShow);
}

// doubt that will help us here (in launcher.dll) though
extern "C"
{
	__declspec(dllexport) DWORD AmdPowerXpressRequestHighPerformance = 0x00000001;
	__declspec(dllexport) DWORD NvOptimusEnablement = 0x00000001;
}