/*
 * $XConsortium: Porthole.c,v 1.16 94/04/17 20:12:34 kaleb Exp $
 *
Copyright (c) 1990, 1994  X Consortium

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of the X Consortium shall not be
used in advertising or otherwise to promote the sale, use or other dealings
in this Software without prior written authorization from the X Consortium.
 *
 * Author:  Jim Fulton, MIT X Consortium
 * 
 * This widget is a trivial clipping widget.  It is typically used with a
 * panner or scrollbar to navigate.
 */

#include <X11/IntrinsicP.h>
#include <X11/StringDefs.h>		/* get XtN and XtC defines */
#include <X11/Xaw/XawInit.h>		/* get Xaw initialize stuff */
#include <X11/Xaw/PortholeP.h>		/* get porthole structs */
#include <X11/Xmu/Misc.h>		/* for MAX */


/*
 * resources for the porthole
 */
static XtResource resources[] = {
#define poff(field) XtOffsetOf(PortholeRec, porthole.field)
    { XtNreportCallback, XtCReportCallback, XtRCallback, sizeof(XtPointer),
	poff(report_callbacks), XtRCallback, (XtPointer) NULL },
#undef poff
};


/*
 * widget class methods used below
 */
static void Realize();			/* set gravity and upcall */
static void Resize();			/* report new size */
static XtGeometryResult GeometryManager();  /* deal with child requests */
static void ChangeManaged();		/* somebody added a new widget */
static XtGeometryResult QueryGeometry();  /* say how big would like to be */

PortholeClassRec portholeClassRec = {
  { /* core fields */
    /* superclass		*/	(WidgetClass) &compositeClassRec,
    /* class_name		*/	"Porthole",
    /* widget_size		*/	sizeof(PortholeRec),
    /* class_initialize		*/	XawInitializeWidgetSet,
    /* class_part_initialize	*/	NULL,
    /* class_inited		*/	FALSE,
    /* initialize		*/	NULL,
    /* initialize_hook		*/	NULL,
    /* realize			*/	Realize,
    /* actions			*/	NULL,
    /* num_actions		*/	0,
    /* resources		*/	resources,
    /* num_resources		*/	XtNumber(resources),
    /* xrm_class		*/	NULLQUARK,
    /* compress_motion		*/	TRUE,
    /* compress_exposure	*/	TRUE,
    /* compress_enterleave	*/	TRUE,
    /* visible_interest		*/	FALSE,
    /* destroy			*/	NULL,
    /* resize			*/	Resize,
    /* expose			*/	NULL,
    /* set_values		*/	NULL,
    /* set_values_hook		*/	NULL,
    /* set_values_almost	*/	XtInheritSetValuesAlmost,
    /* get_values_hook		*/	NULL,
    /* accept_focus		*/	NULL,
    /* version			*/	XtVersion,
    /* callback_private		*/	NULL,
    /* tm_table			*/	NULL,
    /* query_geometry		*/	QueryGeometry,
    /* display_accelerator	*/	XtInheritDisplayAccelerator,
    /* extension		*/	NULL
  },
  { /* composite fields */
    /* geometry_manager		*/	GeometryManager,
    /* change_managed		*/	ChangeManaged,
    /* insert_child		*/	XtInheritInsertChild,
    /* delete_child		*/	XtInheritDeleteChild,
    /* extension		*/	NULL
  },
  { /* porthole fields */
    /* ignore                   */	0
  }
};

WidgetClass portholeWidgetClass = (WidgetClass) &portholeClassRec;


/*****************************************************************************
 *                                                                           *
 *			       utility routines                              *
 *                                                                           *
 *****************************************************************************/

static Widget find_child (pw)
    PortholeWidget pw;
{
    Widget *children;
    int i;

    /*
     * Find the managed child on which we should operate.  Ignore multiple
     * managed children.
     */
    for (i = 0, children = pw->composite.children;
	 i < pw->composite.num_children; i++, children++) {
	if (XtIsManaged(*children)) return *children;
    }

    return (Widget) NULL;
}

static void SendReport (pw, changed)
    PortholeWidget pw;
    unsigned int changed;
{
    Widget child = find_child (pw);

    if (pw->porthole.report_callbacks && child) {
	XawPannerReport prep;

	prep.changed = changed;
	prep.slider_x = -child->core.x;	/* porthole is "inner" */
	prep.slider_y = -child->core.y;	/* child is outer since it is larger */
	prep.slider_width = pw->core.width;
	prep.slider_height = pw->core.height;
	prep.canvas_width = child->core.width;
	prep.canvas_height = child->core.height;
	XtCallCallbackList ((Widget)pw, pw->porthole.report_callbacks,
			    (XtPointer) &prep);
    }
}


static void layout_child (pw, child, geomp, xp, yp, widthp, heightp)
    PortholeWidget pw;
    Widget child;
    XtWidgetGeometry *geomp;
    Position *xp, *yp;
    Dimension *widthp, *heightp;
{
    Position minx, miny;

    *xp = child->core.x;		/* default to current values */
    *yp = child->core.y;
    *widthp = child->core.width;
    *heightp = child->core.height;
    if (geomp) {			/* mix in any requested changes */
	if (geomp->request_mode & CWX) *xp = geomp->x;
	if (geomp->request_mode & CWY) *yp = geomp->y;
	if (geomp->request_mode & CWWidth) *widthp = geomp->width;
	if (geomp->request_mode & CWHeight) *heightp = geomp->height;
    }

    /*
     * Make sure that the child is at least as large as the porthole; there
     * is no maximum size.
     */
    if (*widthp < pw->core.width) *widthp = pw->core.width;
    if (*heightp < pw->core.height) *heightp = pw->core.height;

    /*
     * Make sure that the child is still on the screen.  Note that this must
     * be done *after* the size computation so that we know where to put it.
     */
    minx = ((Position) pw->core.width) - ((Position) *widthp);
    miny = ((Position) pw->core.height) - ((Position) *heightp);

    if (*xp < minx) *xp = minx;		/* keep at lower right corner */
    if (*yp < miny) *yp = miny;

    if (*xp > 0) *xp = 0;		/* keep at upper left corner */
    if (*yp > 0) *yp = 0;
}



/*****************************************************************************
 *                                                                           *
 *			 Porthole Widget Class Methods                       *
 *                                                                           *
 *****************************************************************************/


static void Realize (gw, valueMask, attributes)
    Widget gw;
    Mask *valueMask;
    XSetWindowAttributes *attributes;
{
    attributes->bit_gravity = NorthWestGravity;
    *valueMask |= CWBitGravity;

    if (gw->core.width < 1) gw->core.width = 1;
    if (gw->core.height < 1) gw->core.height = 1;
    (*portholeWidgetClass->core_class.superclass->core_class.realize)
	(gw, valueMask, attributes);
}


static void Resize (gw)
    Widget gw;
{
    PortholeWidget pw = (PortholeWidget) gw;
    Widget child = find_child (pw);

    /*
     * If we have a child, we need to make sure that it is at least as big
     * as we are and in the right place.
     */
    if (child) {
	Position x, y;
	Dimension width, height;

	layout_child (pw, child, (XtWidgetGeometry *)NULL, 
		      &x, &y, &width, &height);
	XtConfigureWidget (child, x, y, width, height, (Dimension) 0);
    }

    SendReport (pw, (unsigned int) (XawPRCanvasWidth | XawPRCanvasHeight));
}


static XtGeometryResult QueryGeometry (gw, intended, preferred)
    Widget gw;
    XtWidgetGeometry *intended, *preferred;
{
    PortholeWidget pw = (PortholeWidget) gw;
    Widget child = find_child (pw);

    if (child) {
#define SIZEONLY (CWWidth | CWHeight)
	preferred->request_mode = SIZEONLY;
	preferred->width = child->core.width;
	preferred->height = child->core.height;

	if (((intended->request_mode & SIZEONLY) == SIZEONLY) &&
	    intended->width == preferred->width &&
	    intended->height == preferred->height)
	  return XtGeometryYes;
	else if (preferred->width == pw->core.width &&
		 preferred->height == pw->core.height)
	  return XtGeometryNo;
	else
	  return XtGeometryAlmost;
#undef SIZEONLY
    } 
    return XtGeometryNo;
}


static XtGeometryResult GeometryManager (w, req, reply)
    Widget w;
    XtWidgetGeometry *req, *reply;
{
    PortholeWidget pw = (PortholeWidget) w->core.parent;
    Widget child = find_child (pw);
    Boolean okay = TRUE;

    if (child != w) return XtGeometryNo;  /* unknown child */

    *reply = *req;			/* assume we'll grant everything */

    if ((req->request_mode & CWBorderWidth) && req->border_width != 0) {
	reply->border_width = 0;	/* require border width of 0 */
	okay = FALSE;
    }

    layout_child (pw, child, req, &reply->x, &reply->y,
		  &reply->width, &reply->height);

    if ((req->request_mode & CWX) && req->x != reply->x) okay = FALSE;
    if ((req->request_mode & CWY) && req->x != reply->x) okay = FALSE;
    if ((req->request_mode & CWWidth) && req->width != reply->width)
      okay = FALSE;
    if ((req->request_mode & CWHeight) && req->height != reply->height)
      okay = FALSE;


    /*
     * If we failed on anything, simply return without touching widget
     */
    if (!okay) return XtGeometryAlmost;

    /*
     * If not just doing a query, update widget and send report.  Note that
     * we will often set fields that weren't requested because we want to keep
     * the child visible.
     */
    if (!(req->request_mode & XtCWQueryOnly)) {
	unsigned int changed = 0;

	if (child->core.x != reply->x) {
	    changed |= XawPRSliderX;
	    child->core.x = reply->x;
	}
	if (child->core.y != reply->y) {
	    changed |= XawPRSliderY;
	    child->core.y = reply->y;
	}
	if (child->core.width != reply->width) {
	    changed |= XawPRSliderWidth;
	    child->core.width = reply->width;
	}
	if (child->core.height != reply->height) {
	    changed |= XawPRSliderHeight;
	    child->core.height = reply->height;
	}
	if (changed) SendReport (pw, changed);
    }

    return XtGeometryYes;		/* success! */
}


static void ChangeManaged (gw)
    Widget gw;
{
    PortholeWidget pw = (PortholeWidget) gw;
    Widget child = find_child (pw);	/* ignore extra children */

    if (child) {
	if (!XtIsRealized (gw)) {
	    XtWidgetGeometry geom, retgeom;

	    geom.request_mode = 0;
	    if (pw->core.width == 0) {
		geom.width = child->core.width;
		geom.request_mode |= CWWidth;
	    }
	    if (pw->core.height == 0) {
		geom.height = child->core.height;
		geom.request_mode |= CWHeight;
	    }
	    if (geom.request_mode &&
		XtMakeGeometryRequest (gw, &geom, &retgeom) == XtGeometryAlmost) {
	        (void) XtMakeGeometryRequest (gw, &retgeom, (XtWidgetGeometry *)NULL);
	    }
	}
	
	XtResizeWidget (child, Max (child->core.width, pw->core.width),
			Max (child->core.height, pw->core.height), 0);

	SendReport (pw, (unsigned int) XawPRAll);
    }
}
