#include <Windows.h>
#pragma comment( lib, "gdi32.lib" )
#pragma comment( lib, "user32.lib" )

#include <stdio.h>

#include <d3d8.h>
#pragma comment( lib, "d3d8.lib" )

#include <detours.h>
#pragma comment( lib, "detours.lib" )

typedef HRESULT( WINAPI* tEndScene ) ( IDirect3DDevice8* );
tEndScene pEndScene = NULL;

void FillRGB( int x, int y, int w, int h, D3DCOLOR color, IDirect3DDevice8* pDevice )
{
    D3DRECT rec = { x, y, x + w, y + h };
    pDevice->Clear( 1, &rec, D3DCLEAR_TARGET, color, 0, 0 );
}

HRESULT WINAPI hkEndScene( IDirect3DDevice8* pDevice )
{
    FillRGB( 10, 10, 100, 100, 0xFF00FF00, pDevice );

    return pEndScene( pDevice );
}

LRESULT CALLBACK MsgProc( HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam )
{
    return DefWindowProc( hwnd, uMsg, wParam, lParam );
}

DWORD WINAPI MainThread( LPVOID )
{
    WNDCLASSEXA wc = { sizeof( WNDCLASSEXA ), CS_CLASSDC, MsgProc, 0L, 0L, GetModuleHandle( NULL ), NULL, NULL, NULL, NULL, "DX", NULL };
    RegisterClassExA( &wc );
    HWND hWnd = CreateWindowA( "DX", NULL, WS_OVERLAPPED | WS_SYSMENU | WS_MINIMIZEBOX, 100, 100, 300, 300, GetDesktopWindow(), NULL, wc.hInstance, NULL );

    D3DPRESENT_PARAMETERS d3dpp;
    LPDIRECT3DDEVICE8 pd3dDevice;
    IDirect3D8 *pd3dInterface = Direct3DCreate8( D3D_SDK_VERSION );

    ZeroMemory( &d3dpp, sizeof( d3dpp ) );
    d3dpp.Windowed = TRUE;
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
    d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;
    HRESULT hr = pd3dInterface->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd, D3DCREATE_SOFTWARE_VERTEXPROCESSING, &d3dpp, &pd3dDevice );
    if ( FAILED( hr ) )
    {
        if ( hr == E_NOTIMPL )
            MessageBox( NULL, L"Could not create device, please make sure the target window is not minimized", L"Error", MB_OK );
        else
            MessageBox( NULL, L"Could not create device", L"Error", MB_OK );

        return 0;
    }

    PDWORD VTable = ( PDWORD ) pd3dDevice;
    VTable = ( PDWORD )VTable[0];

    pEndScene = ( tEndScene )DetourFunction( ( PBYTE )VTable[35], ( PBYTE )hkEndScene );

    // Debug
    /*char buf[256];
    sprintf_s( buf, "0x%p", pd3dDevice );
    MessageBoxA( nullptr, buf, "", MB_OK );*/

    return 0;
}

BOOL WINAPI DllMain( HINSTANCE hModule, DWORD dwReason, LPVOID lpvReserved )
{
    if ( dwReason == DLL_PROCESS_ATTACH )
    {
        DisableThreadLibraryCalls( hModule );
        CreateThread( nullptr, 0, MainThread, hModule, 0, nullptr );
        return TRUE;
    }

    return FALSE;
}