/**
 *
 * $Id: TrackLoc.c,v 1.4 1998/09/12 15:05:47 rwscott Exp $
 *
 * Copyright (C) 1995 Free Software Foundation, Inc.
 *
 * This file is part of the GNU LessTif Library.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 **/

static const char rcsid[] = "$Id: TrackLoc.c,v 1.4 1998/09/12 15:05:47 rwscott Exp $";

#include <LTconfig.h>
#include <XmI/XmI.h>
#include <Xm/XmP.h>

#include <XmI/DebugUtil.h>

Widget
XmTrackingEvent(Widget widget, Cursor cursor,
		Boolean confine_to, XEvent *event_return)
{
    Window confine_to_this;
    XEvent ev;
    Boolean key_pressed = False;
    Time time;

    if (confine_to)
    {
	confine_to_this = XtWindow(widget);
    }
    else
    {
	confine_to_this = None;
    }

    DEBUGOUT(XdbDebug(__FILE__, widget, "XmTrackingEvent: XtGrabPointer()\n"));

    time = XtLastTimestampProcessed(XtDisplay(widget));
    if (XtGrabPointer(widget, True,
		  ButtonReleaseMask | ButtonPressMask,
		  GrabModeAsync, GrabModeAsync,
		  confine_to_this, cursor, time) != GrabSuccess)
    {
	_XmWarning(widget, "XmTrackingEvent: Could not grab pointer");
	return NULL;
    }

    while (True)
    {
	XtAppNextEvent(XtWidgetToApplicationContext(widget), &ev);
	time = XtLastTimestampProcessed(XtDisplay(widget));

	if (ev.xbutton.type == KeyPress)
	{
	    /* Avoid exiting upon releasing the key that caused
		XmTrackingEvent() to be invoked. */
	} else if ((ev.xbutton.type == KeyRelease && key_pressed) ||
		   (ev.xbutton.type == ButtonRelease && ev.xbutton.button == 1))
	{
	    if (event_return != NULL)
		*event_return = ev;

	    DEBUGOUT(XdbDebug(__FILE__, widget,
			      "XmTrackingEvent: XtUngrabPointer()\n"));

	    XtUngrabPointer(widget, time);

	    /* If the button was clicked outside of this programs windows,
	     * the widget that grabbed the pointer will get the event.  So,
	     * we check the bounds of the widget against the coordinates of
	     * the event.  If they're outside, we return NULL.  Otherwise we
	     * return the widget in which the event occured.
	     */
	    if (ev.xbutton.window == XtWindow(widget)
		&& (ev.xbutton.x < XtX(widget)
		    || ev.xbutton.y < XtY(widget)
		    || ev.xbutton.x > XtX(widget) + XtWidth(widget)
		    || ev.xbutton.y > XtY(widget) + XtHeight(widget)))
	    {
		return NULL;
	    }
	    else
	    {
		return XtWindowToWidget(XtDisplay(widget),
					ev.xbutton.window);
	    }
	}
    }
}

Widget
XmTrackingLocate(Widget widget, Cursor cursor, Boolean confine_to)
{
    XEvent ev;

    return XmTrackingEvent(widget, cursor, confine_to, &ev);
}
