/* GTK - The GIMP Toolkit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
 */

#include "gtkvbbox.h"


static void gtk_vbutton_box_class_init    (GtkVButtonBoxClass   *klass);
static void gtk_vbutton_box_init          (GtkVButtonBox        *box);
static void gtk_vbutton_box_size_request  (GtkWidget      *widget,
					   GtkRequisition *requisition);
static void gtk_vbutton_box_size_allocate (GtkWidget      *widget,
					   GtkAllocation  *allocation);

static gint default_spacing = 10;
static GtkButtonBoxStyle default_layout_style = GTK_BUTTONBOX_EDGE;

GType
gtk_vbutton_box_get_type (void)
{
  static GType vbutton_box_type = 0;

  if (!vbutton_box_type)
    {
      static const GTypeInfo vbutton_box_info =
      {
	sizeof (GtkVButtonBoxClass),
	NULL,		/* base_init */
	NULL,		/* base_finalize */
	(GClassInitFunc) gtk_vbutton_box_class_init,
	NULL,		/* class_finalize */
	NULL,		/* class_data */
	sizeof (GtkVButtonBox),
	0,		/* n_preallocs */
	(GInstanceInitFunc) gtk_vbutton_box_init,
      };

      vbutton_box_type =
	g_type_register_static (GTK_TYPE_BUTTON_BOX, "GtkVButtonBox",
				&vbutton_box_info, 0);
    }

  return vbutton_box_type;
}

static void
gtk_vbutton_box_class_init (GtkVButtonBoxClass *class)
{
  GtkWidgetClass *widget_class;

  widget_class = (GtkWidgetClass*) class;

  widget_class->size_request = gtk_vbutton_box_size_request;
  widget_class->size_allocate = gtk_vbutton_box_size_allocate;
}

static void
gtk_vbutton_box_init (GtkVButtonBox *vbutton_box)
{
  /* button_box_init has done everything allready */
}

GtkWidget*
gtk_vbutton_box_new (void)
{
  GtkVButtonBox *vbutton_box;

  vbutton_box = g_object_new (GTK_TYPE_VBUTTON_BOX, NULL);

  return GTK_WIDGET (vbutton_box);
}



/* set default value for spacing */

void
gtk_vbutton_box_set_spacing_default (gint spacing)
{
  default_spacing = spacing;
}


/* set default value for layout style */

void
gtk_vbutton_box_set_layout_default (GtkButtonBoxStyle layout)
{
  g_return_if_fail (layout >= GTK_BUTTONBOX_DEFAULT_STYLE &&
		    layout <= GTK_BUTTONBOX_END);

  default_layout_style = layout;
}

/* get default value for spacing */

gint
gtk_vbutton_box_get_spacing_default (void)
{
  return default_spacing;
}



/* get default value for layout style */

GtkButtonBoxStyle
gtk_vbutton_box_get_layout_default (void)
{
  return default_layout_style;
}




static void
gtk_vbutton_box_size_request (GtkWidget      *widget,
			      GtkRequisition *requisition)
{
  GtkBox *box;
  GtkButtonBox *bbox;
  gint nvis_children;
  gint child_width;
  gint child_height;
  gint spacing;
  GtkButtonBoxStyle layout;
  
  box = GTK_BOX (widget);
  bbox = GTK_BUTTON_BOX (widget);

  spacing = box->spacing;
  layout = bbox->layout_style != GTK_BUTTONBOX_DEFAULT_STYLE
	  ? bbox->layout_style : default_layout_style;
  
  _gtk_button_box_child_requisition (widget,
                                     &nvis_children,
				     NULL,
                                     &child_width,
                                     &child_height);

  if (nvis_children == 0)
    {
      requisition->width = 0; 
      requisition->height = 0;
    }
  else
    {
      switch (layout)
      {
      case GTK_BUTTONBOX_SPREAD:
        requisition->height =
		nvis_children*child_height + ((nvis_children+1)*spacing);
	break;
      case GTK_BUTTONBOX_EDGE:
      case GTK_BUTTONBOX_START:
      case GTK_BUTTONBOX_END:
        requisition->height =
		nvis_children*child_height + ((nvis_children-1)*spacing);
	break;
      default:
	    g_assert_not_reached();
	    break;
      }
	  
      requisition->width = child_width;
    }
	  
  requisition->width += GTK_CONTAINER (box)->border_width * 2;
  requisition->height += GTK_CONTAINER (box)->border_width * 2;
}



static void
gtk_vbutton_box_size_allocate (GtkWidget     *widget,
			       GtkAllocation *allocation)
{
  GtkBox *base_box;
  GtkButtonBox *box;
  GtkVButtonBox *hbox;
  GtkBoxChild *child;
  GList *children;
  GtkAllocation child_allocation;
  gint nvis_children;
  gint n_secondaries;
  gint child_width;
  gint child_height;
  gint x = 0;
  gint y = 0;
  gint secondary_y = 0;
  gint height;
  gint childspace;
  gint childspacing = 0;
  GtkButtonBoxStyle layout;
  gint spacing;
  
  base_box = GTK_BOX (widget);
  box = GTK_BUTTON_BOX (widget);
  hbox = GTK_VBUTTON_BOX (widget);
  spacing = base_box->spacing;
  layout = box->layout_style != GTK_BUTTONBOX_DEFAULT_STYLE
	  ? box->layout_style : default_layout_style;
  _gtk_button_box_child_requisition (widget,
                                     &nvis_children,
				     &n_secondaries,
                                     &child_width,
                                     &child_height);
  widget->allocation = *allocation;
  height = allocation->height - GTK_CONTAINER (box)->border_width*2;
  switch (layout)
  {
  case GTK_BUTTONBOX_SPREAD:
    childspacing = (height - (nvis_children * child_height)) / (nvis_children + 1);
    y = allocation->y + GTK_CONTAINER (box)->border_width + childspacing;
    secondary_y = y + ((nvis_children - n_secondaries) * (child_height + childspacing));
    break;
  case GTK_BUTTONBOX_EDGE:
    if (nvis_children >= 2)
      {
        childspacing = (height - (nvis_children*child_height)) / (nvis_children-1);
	y = allocation->y + GTK_CONTAINER (box)->border_width;
	secondary_y = y + ((nvis_children - n_secondaries) * (child_height + childspacing));
      }
    else
      {
	/* one or zero children, just center */
	childspacing = height;
	y = secondary_y = allocation->y + (allocation->height - child_height) / 2;
      }
    break;
  case GTK_BUTTONBOX_START:
    childspacing = spacing;
    y = allocation->y + GTK_CONTAINER (box)->border_width;
    secondary_y = allocation->y + allocation->height
      - child_height * n_secondaries
      - spacing * (n_secondaries - 1)
      - GTK_CONTAINER (box)->border_width;
    break;
  case GTK_BUTTONBOX_END:
    childspacing = spacing;
    y = allocation->y + allocation->height 
      - child_height * (nvis_children - n_secondaries)
      - spacing * (nvis_children - n_secondaries - 1)
      - GTK_CONTAINER (box)->border_width;
    secondary_y = allocation->y + GTK_CONTAINER (box)->border_width;
    break;
  default:
    g_assert_not_reached();
    break;
  }
		  
  
  x = allocation->x + (allocation->width - child_width) / 2;
  childspace = child_height + childspacing;

  children = GTK_BOX (box)->children;
	  
  while (children)
    {
      child = children->data;
      children = children->next;

      if (GTK_WIDGET_VISIBLE (child->widget))
	{
	  child_allocation.width = child_width;
	  child_allocation.height = child_height;
	  child_allocation.x = x;
	  
	  if (child->is_secondary)
	    {
	      child_allocation.y = secondary_y;
	      secondary_y += childspace;
	    }
	  else
	    {
	      child_allocation.y = y;
	      y += childspace;
	    }
	  
	  gtk_widget_size_allocate (child->widget, &child_allocation);
	}
    }
}