#include<Windows.h>
#include<d3d9.h>
#include<d3dx9.h>
#include<time.h>
#include<iostream>
using namespace std;
#pragma comment(lib,"d3d9.lib")
#pragma comment(lib,"d3dx9.lib")

const string APPTITLE = "Draw Bitmap Program";

#define SCREENW 800
#define SCREENH 600

#define KEY_DOWN(vk_code)((GetAsyncKeyState(vk_code)&0x8000)?1:0)

LPDIRECT3D9 d3d = NULL;
LPDIRECT3DDEVICE9 d3ddev = NULL;
LPDIRECT3DSURFACE9 backbuffer = NULL;
LPDIRECT3DSURFACE9 surface = NULL;

bool gameover = false;
bool Game_Init(HWND window)
{
    d3d = Direct3DCreate9(D3D_SDK_VERSION);
    if (!d3d)
    {
        MessageBox(window, "Error initializing Direct3D", "Error", MB_OK);
        return false;
    }
    D3DPRESENT_PARAMETERS d3dpp;
    ZeroMemory(&d3dpp, sizeof(d3dpp));
    d3dpp.Windowed = TRUE;
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
    d3dpp.BackBufferFormat = D3DFMT_X8R8G8B8;
    d3dpp.BackBufferCount = 1;
    d3dpp.BackBufferWidth = SCREENW;
    d3dpp.BackBufferHeight = SCREENH;
    d3dpp.hDeviceWindow = window;
    d3d->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, window, D3DCREATE_SOFTWARE_VERTEXPROCESSING, &d3dpp, &d3ddev);
    if (!d3ddev)
    {
        MessageBox(window, "Error creating Dicect3D device", "Error", MB_OK);
        return false;
    }

    d3ddev->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
    HRESULT result = d3ddev->CreateOffscreenPlainSurface(SCREENW, SCREENH, D3DFMT_X8R8G8B8, D3DPOOL_DEFAULT, &surface, NULL);
    if (result != D3D_OK) return false;
    result = D3DXLoadSurfaceFromFile(surface, NULL, NULL, "phtot.png", NULL, D3DX_DEFAULT, 0, NULL);
    if (result != D3D_OK) return false;
    return true;
}

void Game_Run(HWND hwnd)
{
    if (!d3ddev) return;
    d3ddev->GetBackBuffer(0, 0, D3DBACKBUFFER_TYPE_MONO, &backbuffer);
    if (d3ddev->BeginScene())
    {
        d3ddev->StretchRect(surface, NULL, backbuffer, NULL, D3DTEXF_NONE);
        d3ddev->EndScene();
        d3ddev->Present(NULL, NULL, NULL, NULL);
    }
    if (KEY_DOWN(VK_ESCAPE))
        PostMessage(hwnd, WM_DESTROY, 0, 0);
}

void Game_End(HWND hwnd)
{
    if (surface) surface->Release();
    if (d3ddev) d3ddev->Release();
    if (d3d) d3d->Release();
}

LRESULT WINAPI WinProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    switch (msg)
    {
    case WM_DESTROY:
        gameover = true;
        break;
    }
    return DefWindowProc(hWnd, msg, wParam, lParam);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    WNDCLASSEX wc;
    HWND hwnd;
    MSG message;
    wc.cbSize = sizeof(WNDCLASSEX);
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = (WNDPROC)WinProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.lpszMenuName = NULL;
    wc.hIcon = NULL;
    wc.hIconSm = NULL;
    wc.hInstance = hInstance;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wc.lpszClassName = "MainWindowClass";

    if (!RegisterClassEx(&wc))
        return FALSE;
    hwnd = CreateWindow("MainWindowClass", APPTITLE.c_str(), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, SCREENW, SCREENH, NULL, NULL, hInstance, NULL);
   
    if (hwnd == 0)return 0;
    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);
    if (!Game_Init(hwnd)) return FALSE;
    while (!gameover)
    {
        if (PeekMessage(&message, NULL, 0, 0, PM_REMOVE))
        {
            TranslateMessage(&message);
            DispatchMessage(&message);
        }
        Game_Run(hwnd);
    }
    return message.wParam;
}