#define _XOPEN_SOURCE 500

#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
#include <time.h>
#include <sys/ipc.h>
#include <sys/shm.h>

#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xatom.h>
#include <X11/extensions/XShm.h>
#include <X11/extensions/Xv.h>
#include <X11/extensions/Xvlib.h>

#define GUID_RGBA32 0x41424752

int main (int argc, char* argv[]) {
  int		rgb_width = 320;
  int		rgb_height = 200;
  
  int		xv_port = -1;
  int		adaptor;
  int		i, j, ret, _x, _y;
  unsigned int  _d, _w, _h;
  long		secsb, secsa, frames;
  
  XvAdaptorInfo		*ai;

  XvImage		*rgb_image;

  unsigned int		p_num_adaptors;
   	
  Display		*dpy;
  Window		window, _dw;
  XSizeHints		hint;
  XSetWindowAttributes	xswa;
  XVisualInfo		vinfo;
  int			screen;
  unsigned long		mask;
  XEvent		event;
  GC			gc;

  /** for shm */
  int 			shmem_flag = 0;
  XShmSegmentInfo	rgb_shminfo;

  adaptor = -1;
	
  dpy = XOpenDisplay(NULL);
  if (dpy == NULL) {
    printf("Cannot open Display.\n");
    exit (-1);
  }
  
  screen = DefaultScreen(dpy);
  
  /** find best display */
  if (XMatchVisualInfo(dpy, screen, 24, TrueColor, &vinfo)) {
    printf(" found 24bit TrueColor\n");
  } else
    if (XMatchVisualInfo(dpy, screen, 16, TrueColor, &vinfo)) {
      printf(" found 16bit TrueColor\n");
    } else
      if (XMatchVisualInfo(dpy, screen, 15, TrueColor, &vinfo)) {
	printf(" found 15bit TrueColor\n");
      } else
  	if (XMatchVisualInfo(dpy, screen, 8, PseudoColor, &vinfo)) {
	  printf(" found 8bit PseudoColor\n");
  	} else
	  if (XMatchVisualInfo(dpy, screen, 8, GrayScale, &vinfo)) {
	    printf(" found 8bit GrayScale\n");
	  } else
	    if (XMatchVisualInfo(dpy, screen, 8, StaticGray, &vinfo)) {
	      printf(" found 8bit StaticGray\n");
	    } else
	      if (XMatchVisualInfo(dpy, screen, 1, StaticGray, &vinfo)) {
  		printf(" found 1bit StaticGray\n");
	      } else {
  		printf("requires 16 bit display\n");
  		exit (-1);
	      }
  
  hint.x = 1;
  hint.y = 1;
  hint.width = rgb_width;
  hint.height = rgb_height;
  hint.flags = PPosition | PSize;
  
  xswa.colormap =  XCreateColormap(dpy, DefaultRootWindow(dpy), vinfo.visual, AllocNone);
  xswa.event_mask = StructureNotifyMask | ExposureMask;
  xswa.background_pixel = 0;
  xswa.border_pixel = 0;
  
  mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;
  
  window = XCreateWindow(dpy, DefaultRootWindow(dpy),
			 0, 0,
			 rgb_width,
			 rgb_height,
			 0, vinfo.depth,
			 InputOutput,
			 vinfo.visual,
			 mask, &xswa);
  
  XStoreName(dpy, window, "firstxv");
  XSetIconName(dpy, window, "firstxv");
  
  XSelectInput(dpy, window, StructureNotifyMask);
  
  /** Map window */
  XMapWindow(dpy, window);
  
  /** Wait for map. */
  do {
    XNextEvent(dpy, &event);
  }
  while (event.type != MapNotify || event.xmap.event != window);
  
  if (XShmQueryExtension(dpy)) shmem_flag = 1;
  if (!shmem_flag) {
    printf("no shmem available.\n");
    exit (-1);
  }
  
  ret = XvQueryAdaptors(dpy, DefaultRootWindow(dpy),
			&p_num_adaptors, &ai);
  if (ret != Success) {
    if (ret == XvBadExtension)
      printf("XvBadExtension returned at XvQueryExtension.\n");
    else
      if (ret == XvBadAlloc)
	printf("XvBadAlloc returned at XvQueryExtension.\n");
      else
	printf("other error happaned at XvQueryAdaptors.\n");
    exit (-1);
  }
  if (p_num_adaptors > 0) {
    xv_port = ai[0].base_id;
    XvFreeAdaptorInfo(ai);
  }
  if (xv_port == -1)
    exit (0);
  
  gc = XCreateGC(dpy, window, 0, 0);		

  if(XvSetPortAttribute(dpy, xv_port, XInternAtom(dpy, "XV_SET_DEFAULTS", False), 1) != Success) {
    printf("XvSetPortAttribute failed !\n");
    exit (-1);
  }
  if(XvSetPortAttribute(dpy, xv_port, XInternAtom(dpy, "XV_ENCODING", False), GUID_RGBA32) != Success) {
    printf("XvSetPortAttribute failed !\n");
    exit (-1);
  }
  
  rgb_image = XvShmCreateImage(dpy, xv_port, GUID_RGBA32, 0, rgb_width, rgb_height, &rgb_shminfo);
  rgb_shminfo.shmid = shmget(IPC_PRIVATE, rgb_image->data_size, IPC_CREAT | 0777);
  rgb_shminfo.shmaddr = rgb_image->data = shmat(rgb_shminfo.shmid, 0, 0);
  rgb_shminfo.readOnly = False;
  
  if (!XShmAttach(dpy, &rgb_shminfo)) {
    printf("XShmAttach failed !\n");
    exit (-1);
  }

  for (i = 0; i < rgb_image->height; i++) {
    for (j = 0; j < rgb_image->width; j++) {
      uint32_t c = 0x000000;
      if(i<rgb_image->height / 3 &&
	 j<rgb_image->width / 3)
	/* Top left square, fill with RED */
	c = 0xff0000;
      else if(i>=rgb_image->height / 3 && i<2*rgb_image->height / 3 &&
	      j>=rgb_image->width / 3 && j<2*rgb_image->width / 3)
	/* Center square, fill with GREEN */
	c = 0x00ff00; 
      else if(i>=2*rgb_image->height / 3 &&
	      j>=2*rgb_image->width / 3)
	/* Bottom right square, fill with BLUE */
	c = 0x0000ff; 
      ((uint32_t *)rgb_image->data)[rgb_image->width*i + j] = c;
    }
  }
  
  while (1) {
    frames = secsa = secsb = 0;
    time(&secsa);
    while (frames < 200) {	
      XGetGeometry(dpy, window, &_dw, &_x, &_y, &_w, &_h, &_d, &_d);
      
      XvShmPutImage(dpy, xv_port, window, gc, rgb_image,
		    0, 0, rgb_image->width, rgb_image->height,
		    0, 0, _w, _h, True);
      
      frames++;
    }
    time(&secsb);
    printf("%ld frames in %ld seconds; %.4f fps\n", frames, secsb-secsa, (double) frames/(secsb-secsa));
  }
  
  return 0;
}