#include <windows.h>
#include <stdlib.h>
#include <string.h>
#include <tchar.h>

// Global variables
const COLORREF RGB_red = 0x000000FF;
const COLORREF RGB_green = 0x0000FF00;

// The main window class name.
static TCHAR szWindowClass[] = _T("DesktopApp");

// The string that appears in the application's title bar.
static TCHAR szTitle[] = _T("WindowName");

// Stored instance handle for use in Win32 API calls such as FindResource
HINSTANCE hInst;

//  FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
//  PURPOSE:  Processes messages for the main window.
//
//  WM_PAINT    - Paint the main window
//  WM_DESTROY  - post a quit message and return
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) {
 PAINTSTRUCT ps;
 HDC hdc;
 TCHAR text[] = _T("Text");

 switch (message) {
  case WM_PAINT:
   hdc = BeginPaint(hWnd, &ps);

   // Window contents here
   Ellipse(hdc, 100, 100, 200, 200);
   TextOut(hdc, 10, 5, text, _tcslen(text));
   SetTextColor(hdc, RGB_red);
   TextOut(hdc, 10, 20, text, _tcslen(text));
   SetTextColor(hdc, RGB_green);
   TextOut(hdc, 10, 35, text, _tcslen(text));
   MoveToEx(hdc, 100, 100, NULL);
   LineTo(hdc, 200, 200);
   

   EndPaint(hWnd, &ps);
  break;
  // WM_CLOSE (Alt+F4) can be ignored, will end in WM_DESTROY when ignored
  case WM_DESTROY:
   PostQuitMessage(0);
  break;
  default:
   return DefWindowProc(hWnd, message, wParam, lParam);
  break;
  }
 return 0;
}

int WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR lpCmdLine, _In_ int nCmdShow) {
 WNDCLASSEX wcex;

 wcex.cbSize = sizeof(WNDCLASSEX);
 wcex.style = CS_HREDRAW | CS_VREDRAW;
 wcex.lpfnWndProc = WndProc;
 wcex.cbClsExtra = 0;
 wcex.cbWndExtra = 0;
 wcex.hInstance = hInstance;
 wcex.hIcon = LoadIcon(wcex.hInstance, IDI_APPLICATION);
 wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
 wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
 wcex.lpszMenuName = NULL;
 wcex.lpszClassName = szWindowClass;
 wcex.hIconSm = LoadIcon(wcex.hInstance, IDI_APPLICATION);

 if (!RegisterClassEx(&wcex)) {
  MessageBox(NULL, _T("Call to RegisterClassEx failed!"), szWindowClass, NULL);
  return 1;
 }

 // Store instance handle in global variable
 hInst = hInstance;

 // The parameters to CreateWindowEx explained:
 // WS_EX_OVERLAPPEDWINDOW : An optional extended window style.
 // szWindowClass: the name of the application
 // szTitle: the text that appears in the title bar
 // WS_OVERLAPPEDWINDOW: the type of window to create
 // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)
 // 300, 300: initial size (width, length)
 // NULL: the parent of this window
 // NULL: this application does not have a menu bar
 // hInstance: the first parameter from WinMain
 // NULL: not used in this application
 HWND hWnd = CreateWindowEx(WS_EX_OVERLAPPEDWINDOW, szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 300, 300, NULL, NULL, hInstance, NULL);
 if (!hWnd) {
  MessageBox(NULL, _T("Call to CreateWindow failed!"), szWindowClass, NULL);
  return 1;
 }

 // The parameters to ShowWindow explained:
 // hWnd: the value returned from CreateWindow
 // nCmdShow: the fourth parameter from WinMain
 ShowWindow(hWnd, nCmdShow);
 UpdateWindow(hWnd);

 // Main message loop:
 MSG msg;
 while (GetMessage(&msg, NULL, 0, 0)) {
  TranslateMessage(&msg);
  DispatchMessage(&msg);
 }
 return (int)msg.wParam;
}