#include "pch.h"
#include "l2d.h"

// global variables
#pragma data_seg (".d3d9_shared")
myIDirect3DDevice9* gl_pmyIDirect3DDevice9;
myIDirect3D9*       gl_pmyIDirect3D9;
HINSTANCE           gl_hOriginalDll;
HINSTANCE           gl_hThisInstance;
#pragma data_seg ()

FILE *g_fLog = NULL;


BOOL WINAPI DllMain( HINSTANCE hInstDLL, DWORD reason, LPVOID lpvReserved )
{
	lpvReserved = NULL;
	switch( reason )
	{
	case DLL_PROCESS_ATTACH:
		{
			gl_hThisInstance = hInstDLL;
			DisableThreadLibraryCalls( hInstDLL );
			L2D_Initialize();
		} break;
	case DLL_PROCESS_DETACH:
		{
			L2D_Uninitialize();
		} break;
	}
	return TRUE;
}


void L2D_Initialize()
{
	// init Logger
	ErrorLogger_Init();
	ErrorLogger_Enable( true );
#ifdef _DEBUG
	ErrorLogger_EnableLoggingToConsole( true );
#endif
	g_fLog = fopen( "L2Detect2.log", "at" );
	ErrorLogger_SetLogFile( g_fLog );
	ErrorLogger_SetAutoPrependErrorType( true );
#ifdef _DEBUG
	ErrorLogger_SetWarnMessageLevel( LOG_DEBUGDUMP );
#else
	ErrorLogger_SetWarnMessageLevel( LOG_WARNING );
#endif
	log_error( LOG_OK, "L2D_Initialize() called.\n" );
	
	// Initialisation
	gl_hOriginalDll        = NULL;
	gl_hThisInstance       = NULL;
	gl_pmyIDirect3D9       = NULL;
	gl_pmyIDirect3DDevice9 = NULL;	

	// start thread that will run all other
	L2D_ThreadStart();
}

void L2D_Uninitialize()
{
	log_error( LOG_OK, "L2D_Uninitialize() called.\n" );
	
	// Release the system's d3d9.dll
	if( gl_hOriginalDll )
	{
		::FreeLibrary( gl_hOriginalDll );
		gl_hOriginalDll = NULL;
		log_error( LOG_DEBUG, "gl_hOriginalDll (d3d9) unloaded.\n" );
	}

	// close logger
	log_error( LOG_OK, "Closing log. Last message! Bye!\n=======================\n" );
	ErrorLogger_FlushLogFile();
	ErrorLogger_Enable( false );
#ifdef _DEBUG
	ErrorLogger_EnableLoggingToConsole( false );
#endif
	if( g_fLog )
	{
		ErrorLogger_SetLogFile( NULL );
		fflush( g_fLog );
		fclose( g_fLog );
		g_fLog = NULL;
	}
}

void LoadOriginalDll()
{
	wchar_t buffer[MAX_PATH];
	buffer[0] = 0;
	// Getting path to system dir and to d3d8.dll
	::GetSystemDirectory( buffer, MAX_PATH );
	// Append dll name
	wcscat( buffer, L"\\d3d9.dll" );
	// try to load the system's d3d9.dll, if pointer empty
	if( !gl_hOriginalDll ) gl_hOriginalDll = ::LoadLibrary( buffer );
	// Debug
	if( !gl_hOriginalDll )
	{
		log_error( LOG_ERROR, "LoadOriginalDll(): Original d3d9.dll not loaded!\n");
		ErrorLogger_FlushLogFile();
		::ExitProcess(0);
	}
}


// Exported function (faking d3d9.dll's one-and-only export)
IDirect3D9* WINAPI Direct3DCreate9( UINT SDKVersion )
{
	if( !gl_hOriginalDll ) LoadOriginalDll(); // looking for the "right d3d9.dll"

	// Hooking IDirect3D Object from Original Library
	typedef IDirect3D9 *(WINAPI* D3D9_Type)(UINT SDKVersion);
	D3D9_Type D3DCreate9_fn = (D3D9_Type)GetProcAddress( gl_hOriginalDll, "Direct3DCreate9" );

	// Debug
	if( !D3DCreate9_fn ) 
	{
		log_error( LOG_ERROR, "Direct3DCreate9(): Pointer to original Direct3DCreate9 function not received!\n" );
		ErrorLogger_FlushLogFile();
		::ExitProcess(0); // exit the hard way
	}

	// Request pointer from Original Dll. 
	IDirect3D9 *pIDirect3D9_orig = D3DCreate9_fn( SDKVersion );

	// Create my IDirect3D8 object and store pointer to original object there.
	// note: the object will delete itself once Ref count is zero (similar to COM objects)
	gl_pmyIDirect3D9 = new myIDirect3D9( pIDirect3D9_orig );

	// Return pointer to hooking Object instead of "real one"
	return gl_pmyIDirect3D9;
}