#include <X11/Xlibint.h>
#include "gdkasync.h"
#include "gdkx.h"
#include "string.h"

typedef struct _SetInputFocusState SetInputFocusState;

struct _SetInputFocusState
{
  Display *dpy;
  Window window;
  _XAsyncHandler async;
  gulong set_input_focus_req;
  gulong get_input_focus_req;
  gboolean have_error;
  GdkSendXEventCallback callback;
  gpointer data;
};

static Bool
set_input_focus_handler (Display *dpy,
			 xReply  *rep,
			 char    *buf,
			 int      len,
			 XPointer data)
{
  SetInputFocusState *state = (SetInputFocusState *)data;  

  if (dpy->last_request_read == state->set_input_focus_req)
    {
      if (rep->generic.type == X_Error &&
	  rep->error.errorCode == BadMatch)
	{
	  /* Consume BadMatch errors, since we have no control
	   * over them.
	   */
	  return True;
	}
    }
  
  if (dpy->last_request_read == state->get_input_focus_req)
    {
      xGetInputFocusReply replbuf;
      xGetInputFocusReply *repl;
      
      if (rep->generic.type != X_Error)
	{
	  /* Actually does nothing, since there are no additional bytes
	   * to read, but maintain good form.
	   */
	  repl = (xGetInputFocusReply *)
	    _XGetAsyncReply(dpy, (char *)&replbuf, rep, buf, len,
			    (sizeof(xGetInputFocusReply) - sizeof(xReply)) >> 2,
			    True);
	}

      DeqAsyncHandler(state->dpy, &state->async);

      g_free (state);
      
      return (rep->generic.type != X_Error);
    }

  return False;
}

void
_gdk_x11_set_input_focus_safe (GdkDisplay             *display,
			       Window                  window,
			       int                     revert_to,
			       Time                    time)
{
  Display *dpy;
  SetInputFocusState *state;
  
  dpy = GDK_DISPLAY_XDISPLAY (display);

  state = g_new (SetInputFocusState, 1);

  state->dpy = dpy;
  state->window = window;
  
  LockDisplay(dpy);

  state->async.next = dpy->async_handlers;
  state->async.handler = set_input_focus_handler;
  state->async.data = (XPointer) state;
  dpy->async_handlers = &state->async;

  {
    xSetInputFocusReq *req;
    
    GetReq(SetInputFocus, req);
    req->focus = window;
    req->revertTo = revert_to;
    req->time = time;
    state->set_input_focus_req = dpy->request;
  }

  /*
   * XSync (dpy, 0)
   */
  {
    xReq *req;
    
    GetEmptyReq(GetInputFocus, req);
    state->get_input_focus_req = dpy->request;
  }
  
  UnlockDisplay(dpy);
  SyncHandle();
}