// Testcase showing assertion failure in Cairo 1.10.0 when using CAIRO_OPERATOR_DIFFERENCE on win32 surfaces.


#include <windows.h>
#include <stdio.h>
#include <cairo.h>
#include <cairo-win32.h>


static void paint_cairo(cairo_t *cr){
  cairo_set_source_rgb(cr, 1,1,1);
  cairo_paint(cr);
  
  cairo_move_to(cr, 0.3, 0.3);
  cairo_line_to(cr, 0.7, 0.3);
  cairo_line_to(cr, 0.7, 0.7);
  
  // comment out the following line to get a triangle => no crash
  cairo_line_to(cr, 0.3, 0.7);
  
  cairo_set_operator(cr, CAIRO_OPERATOR_DIFFERENCE);
  cairo_set_source_rgb(cr, 1,1,1);
  cairo_fill(cr); // booom!
}

static void on_paint(HDC hdc, long width, long height){
  cairo_surface_t *surface = cairo_win32_surface_create(hdc);
  cairo_t *cr = cairo_create(surface);
  
  cairo_scale(cr, width, height);
  paint_cairo(cr);
  
  cairo_destroy(cr);
  cairo_surface_destroy(surface);
}

LRESULT CALLBACK WndProc(HWND window, UINT message, WPARAM wParam, LPARAM lParam){
  PAINTSTRUCT paintStruct;
  HBITMAP buffer;
  HDC dc, bufferdc;
  RECT clientRect;
 
  switch(message){
    case WM_ERASEBKGND:
      return 0;

    case WM_PAINT:
      GetClientRect(window, &clientRect);
      dc = BeginPaint(window, &paintStruct);

      bufferdc = CreateCompatibleDC(dc);
      buffer = CreateCompatibleBitmap(dc, clientRect.right, clientRect.bottom);
      SelectObject(bufferdc, buffer); 
      
      on_paint(bufferdc, clientRect.right, clientRect.bottom);
      
      BitBlt(dc, 0, 0, clientRect.right, clientRect.bottom, bufferdc, 0, 0, SRCCOPY); 
      DeleteDC(bufferdc); 
      DeleteObject(buffer);

      EndPaint(window, &paintStruct);
      return 0;
    
    case WM_DESTROY:
      PostQuitMessage(0);
      return 0;
  }

  return DefWindowProc(window, message, wParam, lParam);
}

INT WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR lpCmdLine, INT iCmdShow){
  HWND window;
  MSG message;
  WNDCLASS window_class;
  RECT rect;
  
  printf("cairo version: %s\n", cairo_version_string());

  DWORD windowStyle = WS_OVERLAPPEDWINDOW;
  const char * windowClassName = "Cairo Test";

  window_class.style = CS_HREDRAW | CS_VREDRAW;
  window_class.lpfnWndProc = WndProc;
  window_class.cbClsExtra = 0;
  window_class.cbWndExtra = 0;
  window_class.hInstance = hInstance;
  window_class.hIcon = LoadIcon(NULL, IDI_APPLICATION);
  window_class.hCursor = LoadCursor(NULL, IDC_ARROW);
  window_class.hbrBackground =(HBRUSH)GetStockObject(WHITE_BRUSH);
  window_class.lpszMenuName = NULL;
  window_class.lpszClassName = windowClassName;
 
  RegisterClass(&window_class);
 
  rect.left = 0;
  rect.top = 0;
  rect.right = 400;
  rect.bottom = 400;
  AdjustWindowRect(&rect, windowStyle, FALSE);

  window = CreateWindow(windowClassName,
                        "Cairo Patterns - Test",
                        windowStyle,
                        CW_USEDEFAULT, CW_USEDEFAULT,
                        rect.right - rect.left, rect.bottom - rect.top,
                        NULL,
                        NULL,
                        hInstance,
                        NULL);
 
  ShowWindow(window, iCmdShow);
  UpdateWindow(window);

  while(GetMessage(&message, NULL, 0, 0)){
    TranslateMessage(&message);
    DispatchMessage(&message);
  }
 
  return (int)message.wParam;
}