gtkstack.c

/*
 * Copyright (c) 2013 Red Hat, Inc.
 *
 * This program 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 program 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 program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Author: Alexander Larsson <alexl@redhat.com>
 *
 */

#include "config.h"

#include <gtk/gtk.h>
#include "gtkstack.h"
#include "gtkprivate.h"
#include "gtkintl.h"
#include "gtkcsscustomgadgetprivate.h"
#include "gtkcontainerprivate.h"
#include "gtkprogresstrackerprivate.h"
#include "gtksettingsprivate.h"
#include "gtkwidgetprivate.h"
#include "a11y/gtkstackaccessible.h"
#include "a11y/gtkstackaccessibleprivate.h"
#include <math.h>
#include <string.h>

/**
 * SECTION:gtkstack
 * @Short_description: A stacking container
 * @Title: GtkStack
 * @See_also: #GtkNotebook, #GtkStackSwitcher
 *
 * The GtkStack widget is a container which only shows
 * one of its children at a time. In contrast to GtkNotebook,
 * GtkStack does not provide a means for users to change the
 * visible child. Instead, the #GtkStackSwitcher widget can be
 * used with GtkStack to provide this functionality.
 *
 * Transitions between pages can be animated as slides or
 * fades. This can be controlled with gtk_stack_set_transition_type().
 * These animations respect the #GtkSettings:gtk-enable-animations
 * setting.
 *
 * The GtkStack widget was added in GTK+ 3.10.
 *
 * # CSS nodes
 *
 * GtkStack has a single CSS node named stack.
 */

/**
 * GtkStackTransitionType:
 * @GTK_STACK_TRANSITION_TYPE_NONE: No transition
 * @GTK_STACK_TRANSITION_TYPE_CROSSFADE: A cross-fade
 * @GTK_STACK_TRANSITION_TYPE_SLIDE_RIGHT: Slide from left to right
 * @GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT: Slide from right to left
 * @GTK_STACK_TRANSITION_TYPE_SLIDE_UP: Slide from bottom up
 * @GTK_STACK_TRANSITION_TYPE_SLIDE_DOWN: Slide from top down
 * @GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT_RIGHT: Slide from left or right according to the children order
 * @GTK_STACK_TRANSITION_TYPE_SLIDE_UP_DOWN: Slide from top down or bottom up according to the order
 * @GTK_STACK_TRANSITION_TYPE_OVER_UP: Cover the old page by sliding up. Since 3.12
 * @GTK_STACK_TRANSITION_TYPE_OVER_DOWN: Cover the old page by sliding down. Since: 3.12
 * @GTK_STACK_TRANSITION_TYPE_OVER_LEFT: Cover the old page by sliding to the left. Since: 3.12
 * @GTK_STACK_TRANSITION_TYPE_OVER_RIGHT: Cover the old page by sliding to the right. Since: 3.12
 * @GTK_STACK_TRANSITION_TYPE_UNDER_UP: Uncover the new page by sliding up. Since 3.12
 * @GTK_STACK_TRANSITION_TYPE_UNDER_DOWN: Uncover the new page by sliding down. Since: 3.12
 * @GTK_STACK_TRANSITION_TYPE_UNDER_LEFT: Uncover the new page by sliding to the left. Since: 3.12
 * @GTK_STACK_TRANSITION_TYPE_UNDER_RIGHT: Uncover the new page by sliding to the right. Since: 3.12
 * @GTK_STACK_TRANSITION_TYPE_OVER_UP_DOWN: Cover the old page sliding up or uncover the new page sliding down, according to order. Since: 3.12
 * @GTK_STACK_TRANSITION_TYPE_OVER_DOWN_UP: Cover the old page sliding down or uncover the new page sliding up, according to order. Since: 3.14
 * @GTK_STACK_TRANSITION_TYPE_OVER_LEFT_RIGHT: Cover the old page sliding left or uncover the new page sliding right, according to order. Since: 3.14
 * @GTK_STACK_TRANSITION_TYPE_OVER_RIGHT_LEFT: Cover the old page sliding right or uncover the new page sliding left, according to order. Since: 3.14
 *
 * These enumeration values describe the possible transitions
 * between pages in a #GtkStack widget.
 *
 * New values may be added to this enumeration over time.
 */

/* TODO:
 *  filter events out events to the last_child widget during transitions
 */

enum  {
  PROP_0,
  PROP_HOMOGENEOUS,
  PROP_HHOMOGENEOUS,
  PROP_VHOMOGENEOUS,
  PROP_VISIBLE_CHILD,
  PROP_VISIBLE_CHILD_NAME,
  PROP_TRANSITION_DURATION,
  PROP_TRANSITION_TYPE,
  PROP_TRANSITION_RUNNING,
  PROP_INTERPOLATE_SIZE,
  LAST_PROP
};

enum
{
  CHILD_PROP_0,
  CHILD_PROP_NAME,
  CHILD_PROP_TITLE,
  CHILD_PROP_ICON_NAME,
  CHILD_PROP_POSITION,
  CHILD_PROP_NEEDS_ATTENTION,
  LAST_CHILD_PROP
};

typedef struct _GtkStackChildInfo GtkStackChildInfo;

struct _GtkStackChildInfo {
  GtkWidget *widget;
  gchar *name;
  gchar *title;
  gchar *icon_name;
  gboolean needs_attention;
  GtkWidget *last_focus;
};

typedef struct {
  GList *children;

  GdkWindow* bin_window;
  GdkWindow* view_window;

  GtkStackChildInfo *visible_child;

  GtkCssGadget *gadget;

  gboolean hhomogeneous;
  gboolean vhomogeneous;

  GtkStackTransitionType transition_type;
  guint transition_duration;

  GtkStackChildInfo *last_visible_child;
  cairo_surface_t *last_visible_surface;
  GtkAllocation last_visible_surface_allocation;
  guint tick_id;
  GtkProgressTracker tracker;
  gboolean first_frame_skipped;

  gint last_visible_widget_width;
  gint last_visible_widget_height;

  gboolean interpolate_size;

  GtkStackTransitionType active_transition_type;

} GtkStackPrivate;

static GParamSpec *stack_props[LAST_PROP] = { NULL, };
static GParamSpec *stack_child_props[LAST_CHILD_PROP] = { NULL, };

static void     gtk_stack_add                            (GtkContainer  *widget,
                                                          GtkWidget     *child);
static void     gtk_stack_remove                         (GtkContainer  *widget,
                                                          GtkWidget     *child);
static void     gtk_stack_forall                         (GtkContainer  *container,
                                                          gboolean       include_internals,
                                                          GtkCallback    callback,
                                                          gpointer       callback_data);
static void     gtk_stack_compute_expand                 (GtkWidget     *widget,
                                                          gboolean      *hexpand,
                                                          gboolean      *vexpand);
static void     gtk_stack_size_allocate                  (GtkWidget     *widget,
                                                          GtkAllocation *allocation);
static gboolean gtk_stack_draw                           (GtkWidget     *widget,
                                                          cairo_t       *cr);
static void     gtk_stack_get_preferred_height           (GtkWidget     *widget,
                                                          gint          *minimum_height,
                                                          gint          *natural_height);
static void     gtk_stack_get_preferred_height_for_width (GtkWidget     *widget,
                                                          gint           width,
                                                          gint          *minimum_height,
                                                          gint          *natural_height);
static void     gtk_stack_get_preferred_width            (GtkWidget     *widget,
                                                          gint          *minimum_width,
                                                          gint          *natural_width);
static void     gtk_stack_get_preferred_width_for_height (GtkWidget     *widget,
                                                          gint           height,
                                                          gint          *minimum_width,
                                                          gint          *natural_width);
static void     gtk_stack_finalize                       (GObject       *obj);
static void     gtk_stack_get_property                   (GObject       *object,
                                                          guint          property_id,
                                                          GValue        *value,
                                                          GParamSpec    *pspec);
static void     gtk_stack_set_property                   (GObject       *object,
                                                          guint          property_id,
                                                          const GValue  *value,
                                                          GParamSpec    *pspec);
static void     gtk_stack_get_child_property             (GtkContainer  *container,
                                                          GtkWidget     *child,
                                                          guint          property_id,
                                                          GValue        *value,
                                                          GParamSpec    *pspec);
static void     gtk_stack_set_child_property             (GtkContainer  *container,
                                                          GtkWidget     *child,
                                                          guint          property_id,
                                                          const GValue  *value,
                                                          GParamSpec    *pspec);
static void     gtk_stack_unschedule_ticks               (GtkStack      *stack);
static gint     get_bin_window_x                         (GtkStack            *stack,
                                                          const GtkAllocation *allocation);
static gint     get_bin_window_y                         (GtkStack            *stack,
                                                          const GtkAllocation *allocation);

G_DEFINE_TYPE_WITH_PRIVATE (GtkStack, gtk_stack, GTK_TYPE_CONTAINER)

static void
gtk_stack_dispose (GObject *obj)
{
  GtkStack *stack = GTK_STACK (obj);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  priv->visible_child = NULL;

  G_OBJECT_CLASS (gtk_stack_parent_class)->dispose (obj);
}

static void
gtk_stack_finalize (GObject *obj)
{
  GtkStack *stack = GTK_STACK (obj);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  gtk_stack_unschedule_ticks (stack);

  if (priv->last_visible_surface != NULL)
    cairo_surface_destroy (priv->last_visible_surface);

  g_clear_object (&priv->gadget);

  G_OBJECT_CLASS (gtk_stack_parent_class)->finalize (obj);
}

static void
gtk_stack_get_property (GObject   *object,
                        guint       property_id,
                        GValue     *value,
                        GParamSpec *pspec)
{
  GtkStack *stack = GTK_STACK (object);

  switch (property_id)
    {
    case PROP_HOMOGENEOUS:
      g_value_set_boolean (value, gtk_stack_get_homogeneous (stack));
      break;
    case PROP_HHOMOGENEOUS:
      g_value_set_boolean (value, gtk_stack_get_hhomogeneous (stack));
      break;
    case PROP_VHOMOGENEOUS:
      g_value_set_boolean (value, gtk_stack_get_vhomogeneous (stack));
      break;
    case PROP_VISIBLE_CHILD:
      g_value_set_object (value, gtk_stack_get_visible_child (stack));
      break;
    case PROP_VISIBLE_CHILD_NAME:
      g_value_set_string (value, gtk_stack_get_visible_child_name (stack));
      break;
    case PROP_TRANSITION_DURATION:
      g_value_set_uint (value, gtk_stack_get_transition_duration (stack));
      break;
    case PROP_TRANSITION_TYPE:
      g_value_set_enum (value, gtk_stack_get_transition_type (stack));
      break;
    case PROP_TRANSITION_RUNNING:
      g_value_set_boolean (value, gtk_stack_get_transition_running (stack));
      break;
    case PROP_INTERPOLATE_SIZE:
      g_value_set_boolean (value, gtk_stack_get_interpolate_size (stack));
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
    }
}

static void
gtk_stack_set_property (GObject     *object,
                        guint         property_id,
                        const GValue *value,
                        GParamSpec   *pspec)
{
  GtkStack *stack = GTK_STACK (object);

  switch (property_id)
    {
    case PROP_HOMOGENEOUS:
      gtk_stack_set_homogeneous (stack, g_value_get_boolean (value));
      break;
    case PROP_HHOMOGENEOUS:
      gtk_stack_set_hhomogeneous (stack, g_value_get_boolean (value));
      break;
    case PROP_VHOMOGENEOUS:
      gtk_stack_set_vhomogeneous (stack, g_value_get_boolean (value));
      break;
    case PROP_VISIBLE_CHILD:
      gtk_stack_set_visible_child (stack, g_value_get_object (value));
      break;
    case PROP_VISIBLE_CHILD_NAME:
      gtk_stack_set_visible_child_name (stack, g_value_get_string (value));
      break;
    case PROP_TRANSITION_DURATION:
      gtk_stack_set_transition_duration (stack, g_value_get_uint (value));
      break;
    case PROP_TRANSITION_TYPE:
      gtk_stack_set_transition_type (stack, g_value_get_enum (value));
      break;
    case PROP_INTERPOLATE_SIZE:
      gtk_stack_set_interpolate_size (stack, g_value_get_boolean (value));
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
    }
}

static void
gtk_stack_realize (GtkWidget *widget)
{
  GtkStack *stack = GTK_STACK (widget);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
  GtkAllocation allocation;
  GdkWindowAttr attributes = { 0 };
  GdkWindowAttributesType attributes_mask;
  GtkStackChildInfo *info;
  GList *l;

  gtk_widget_set_realized (widget, TRUE);
  gtk_widget_set_window (widget, g_object_ref (gtk_widget_get_parent_window (widget)));

  gtk_css_gadget_get_content_allocation (priv->gadget, &allocation, NULL);

  attributes.x = allocation.x;
  attributes.y = allocation.y;
  attributes.width = allocation.width;
  attributes.height = allocation.height;
  attributes.window_type = GDK_WINDOW_CHILD;
  attributes.wclass = GDK_INPUT_OUTPUT;
  attributes.visual = gtk_widget_get_visual (widget);
  attributes.event_mask =
    gtk_widget_get_events (widget);
  attributes_mask = (GDK_WA_X | GDK_WA_Y) | GDK_WA_VISUAL;

  priv->view_window =
    gdk_window_new (gtk_widget_get_window (GTK_WIDGET (stack)),
                    &attributes, attributes_mask);
  gtk_widget_register_window (widget, priv->view_window);

  attributes.x = get_bin_window_x (stack, &allocation);
  attributes.y = get_bin_window_y (stack, &allocation);
  attributes.width = allocation.width;
  attributes.height = allocation.height;

  for (l = priv->children; l != NULL; l = l->next)
    {
      info = l->data;
      attributes.event_mask |= gtk_widget_get_events (info->widget);
    }

  priv->bin_window =
    gdk_window_new (priv->view_window, &attributes, attributes_mask);
  gtk_widget_register_window (widget, priv->bin_window);

  for (l = priv->children; l != NULL; l = l->next)
    {
      info = l->data;

      gtk_widget_set_parent_window (info->widget, priv->bin_window);
    }

  gdk_window_show (priv->bin_window);
}

static void
gtk_stack_unrealize (GtkWidget *widget)
{
  GtkStack *stack = GTK_STACK (widget);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  gtk_widget_unregister_window (widget, priv->bin_window);
  gdk_window_destroy (priv->bin_window);
  priv->bin_window = NULL;
  gtk_widget_unregister_window (widget, priv->view_window);
  gdk_window_destroy (priv->view_window);
  priv->view_window = NULL;

  GTK_WIDGET_CLASS (gtk_stack_parent_class)->unrealize (widget);
}

static void
gtk_stack_map (GtkWidget *widget)
{
  GtkStack *stack = GTK_STACK (widget);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  GTK_WIDGET_CLASS (gtk_stack_parent_class)->map (widget);

  gdk_window_show (priv->view_window);
}

static void
gtk_stack_unmap (GtkWidget *widget)
{
  GtkStack *stack = GTK_STACK (widget);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  gdk_window_hide (priv->view_window);

  GTK_WIDGET_CLASS (gtk_stack_parent_class)->unmap (widget);
}

static void
gtk_stack_class_init (GtkStackClass *klass)
{
  GObjectClass *object_class = G_OBJECT_CLASS (klass);
  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
  GtkContainerClass *container_class = GTK_CONTAINER_CLASS (klass);

  object_class->get_property = gtk_stack_get_property;
  object_class->set_property = gtk_stack_set_property;
  object_class->dispose = gtk_stack_dispose;
  object_class->finalize = gtk_stack_finalize;

  widget_class->size_allocate = gtk_stack_size_allocate;
  widget_class->draw = gtk_stack_draw;
  widget_class->realize = gtk_stack_realize;
  widget_class->unrealize = gtk_stack_unrealize;
  widget_class->map = gtk_stack_map;
  widget_class->unmap = gtk_stack_unmap;
  widget_class->get_preferred_height = gtk_stack_get_preferred_height;
  widget_class->get_preferred_height_for_width = gtk_stack_get_preferred_height_for_width;
  widget_class->get_preferred_width = gtk_stack_get_preferred_width;
  widget_class->get_preferred_width_for_height = gtk_stack_get_preferred_width_for_height;
  widget_class->compute_expand = gtk_stack_compute_expand;

  container_class->add = gtk_stack_add;
  container_class->remove = gtk_stack_remove;
  container_class->forall = gtk_stack_forall;
  container_class->set_child_property = gtk_stack_set_child_property;
  container_class->get_child_property = gtk_stack_get_child_property;
  gtk_container_class_handle_border_width (container_class);

  stack_props[PROP_HOMOGENEOUS] =
      g_param_spec_boolean ("homogeneous", P_("Homogeneous"), P_("Homogeneous sizing"),
                            TRUE,
                            GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);

  /**
   * GtkStack:hhomogeneous:
   *
   * %TRUE if the stack allocates the same width for all children.
   *
   * Since: 3.16
   */
  stack_props[PROP_HHOMOGENEOUS] =
      g_param_spec_boolean ("hhomogeneous", P_("Horizontally homogeneous"), P_("Horizontally homogeneous sizing"),
                            TRUE,
                            GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);

  /**
   * GtkStack:vhomogeneous:
   *
   * %TRUE if the stack allocates the same height for all children.
   *
   * Since: 3.16
   */
  stack_props[PROP_VHOMOGENEOUS] =
      g_param_spec_boolean ("vhomogeneous", P_("Vertically homogeneous"), P_("Vertically homogeneous sizing"),
                            TRUE,
                            GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
  stack_props[PROP_VISIBLE_CHILD] =
      g_param_spec_object ("visible-child", P_("Visible child"), P_("The widget currently visible in the stack"),
                           GTK_TYPE_WIDGET,
                           GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
  stack_props[PROP_VISIBLE_CHILD_NAME] =
      g_param_spec_string ("visible-child-name", P_("Name of visible child"), P_("The name of the widget currently visible in the stack"),
                           NULL,
                           GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
  stack_props[PROP_TRANSITION_DURATION] =
      g_param_spec_uint ("transition-duration", P_("Transition duration"), P_("The animation duration, in milliseconds"),
                         0, G_MAXUINT, 200,
                         GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
  stack_props[PROP_TRANSITION_TYPE] =
      g_param_spec_enum ("transition-type", P_("Transition type"), P_("The type of animation used to transition"),
                         GTK_TYPE_STACK_TRANSITION_TYPE, GTK_STACK_TRANSITION_TYPE_NONE,
                         GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
  stack_props[PROP_TRANSITION_RUNNING] =
      g_param_spec_boolean ("transition-running", P_("Transition running"), P_("Whether or not the transition is currently running"),
                            FALSE,
                            GTK_PARAM_READABLE);
  stack_props[PROP_INTERPOLATE_SIZE] =
      g_param_spec_boolean ("interpolate-size", P_("Interpolate size"), P_("Whether or not the size should smoothly change when changing between differently sized children"),
                            FALSE,
                            GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);


  g_object_class_install_properties (object_class, LAST_PROP, stack_props);

  stack_child_props[CHILD_PROP_NAME] =
    g_param_spec_string ("name",
                         P_("Name"),
                         P_("The name of the child page"),
                         NULL,
                         GTK_PARAM_READWRITE);

  stack_child_props[CHILD_PROP_TITLE] =
    g_param_spec_string ("title",
                         P_("Title"),
                         P_("The title of the child page"),
                         NULL,
                         GTK_PARAM_READWRITE);

  stack_child_props[CHILD_PROP_ICON_NAME] =
    g_param_spec_string ("icon-name",
                         P_("Icon name"),
                         P_("The icon name of the child page"),
                         NULL,
                         GTK_PARAM_READWRITE);

  stack_child_props[CHILD_PROP_POSITION] =
    g_param_spec_int ("position",
                      P_("Position"),
                      P_("The index of the child in the parent"),
                      -1, G_MAXINT,
                      0,
                      GTK_PARAM_READWRITE);

  /**
   * GtkStack:needs-attention:
   *
   * Sets a flag specifying whether the child requires the user attention.
   * This is used by the #GtkStackSwitcher to change the appearance of the
   * corresponding button when a page needs attention and it is not the
   * current one.
   *
   * Since: 3.12
   */
  stack_child_props[CHILD_PROP_NEEDS_ATTENTION] =
    g_param_spec_boolean ("needs-attention",
                         P_("Needs Attention"),
                         P_("Whether this page needs attention"),
                         FALSE,
                         GTK_PARAM_READWRITE);

  gtk_container_class_install_child_properties (container_class, LAST_CHILD_PROP, stack_child_props);

  gtk_widget_class_set_accessible_type (widget_class, GTK_TYPE_STACK_ACCESSIBLE);
  gtk_widget_class_set_css_name (widget_class, "stack");
}

/**
 * gtk_stack_new:
 *
 * Creates a new #GtkStack container.
 *
 * Returns: a new #GtkStack
 *
 * Since: 3.10
 */
GtkWidget *
gtk_stack_new (void)
{
  return g_object_new (GTK_TYPE_STACK, NULL);
}

static GtkStackChildInfo *
find_child_info_for_widget (GtkStack  *stack,
                            GtkWidget *child)
{
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
  GtkStackChildInfo *info;
  GList *l;

  for (l = priv->children; l != NULL; l = l->next)
    {
      info = l->data;
      if (info->widget == child)
        return info;
    }

  return NULL;
}

static void
reorder_child (GtkStack  *stack,
               GtkWidget *child,
               gint       position)
{
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
  GList *l;
  GList *old_link = NULL;
  GList *new_link = NULL;
  GtkStackChildInfo *child_info = NULL;
  gint num = 0;

  l = priv->children;

  /* Loop to find the old position and link of child, new link of child and
   * total number of children. new_link will be NULL if the child should be
   * moved to the end (in case of position being < 0 || >= num)
   */
  while (l && (new_link == NULL || old_link == NULL))
    {
      /* Record the new position if found */
      if (position == num)
        new_link = l;

      if (old_link == NULL)
        {
          GtkStackChildInfo *info;
          info = l->data;

          /* Keep trying to find the current position and link location of the child */
          if (info->widget == child)
            {
              old_link = l;
              child_info = info;
            }
        }

      l = l->next;
      num++;
    }

  g_return_if_fail (old_link != NULL);

  if (old_link == new_link || (old_link->next == NULL && new_link == NULL))
    return;

  priv->children = g_list_delete_link (priv->children, old_link);
  priv->children = g_list_insert_before (priv->children, new_link, child_info);

  gtk_container_child_notify_by_pspec (GTK_CONTAINER (stack), child, stack_child_props[CHILD_PROP_POSITION]);
}

static void
gtk_stack_get_child_property (GtkContainer *container,
                              GtkWidget    *child,
                              guint         property_id,
                              GValue       *value,
                              GParamSpec   *pspec)
{
  GtkStack *stack = GTK_STACK (container);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
  GtkStackChildInfo *info;

  info = find_child_info_for_widget (stack, child);
  if (info == NULL)
    {
      GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID (container, property_id, pspec);
      return;
    }

  switch (property_id)
    {
    case CHILD_PROP_NAME:
      g_value_set_string (value, info->name);
      break;

    case CHILD_PROP_TITLE:
      g_value_set_string (value, info->title);
      break;

    case CHILD_PROP_ICON_NAME:
      g_value_set_string (value, info->icon_name);
      break;

    case CHILD_PROP_POSITION:
      g_value_set_int (value, g_list_index (priv->children, info));
      break;

    case CHILD_PROP_NEEDS_ATTENTION:
      g_value_set_boolean (value, info->needs_attention);
      break;

    default:
      GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID (container, property_id, pspec);
      break;
    }
}

static void
gtk_stack_set_child_property (GtkContainer *container,
                              GtkWidget    *child,
                              guint         property_id,
                              const GValue *value,
                              GParamSpec   *pspec)
{
  GtkStack *stack = GTK_STACK (container);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
  GtkStackChildInfo *info;
  GtkStackChildInfo *info2;
  gchar *name;
  GList *l;

  info = find_child_info_for_widget (stack, child);
  if (info == NULL)
    {
      GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID (container, property_id, pspec);
      return;
    }

  switch (property_id)
    {
    case CHILD_PROP_NAME:
      name = g_value_dup_string (value);
      for (l = priv->children; l != NULL; l = l->next)
        {
          info2 = l->data;
          if (info == info2)
            continue;
          if (g_strcmp0 (info2->name, name) == 0)
            {
              g_warning ("Duplicate child name in GtkStack: %s", name);
              break;
            }
        }

      g_free (info->name);
      info->name = name;

      gtk_container_child_notify_by_pspec (container, child, pspec);

      if (priv->visible_child == info)
        g_object_notify_by_pspec (G_OBJECT (stack),
                                  stack_props[PROP_VISIBLE_CHILD_NAME]);

      break;

    case CHILD_PROP_TITLE:
      g_free (info->title);
      info->title = g_value_dup_string (value);
      gtk_container_child_notify_by_pspec (container, child, pspec);
      break;

    case CHILD_PROP_ICON_NAME:
      g_free (info->icon_name);
      info->icon_name = g_value_dup_string (value);
      gtk_container_child_notify_by_pspec (container, child, pspec);
      break;

    case CHILD_PROP_POSITION:
      reorder_child (stack, child, g_value_get_int (value));
      break;

    case CHILD_PROP_NEEDS_ATTENTION:
      info->needs_attention = g_value_get_boolean (value);
      gtk_container_child_notify_by_pspec (container, child, pspec);
      break;

    default:
      GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID (container, property_id, pspec);
      break;
    }
}

static inline gboolean
is_left_transition (GtkStackTransitionType transition_type)
{
  return (transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_LEFT);
}

static inline gboolean
is_right_transition (GtkStackTransitionType transition_type)
{
  return (transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_RIGHT ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_RIGHT);
}

static inline gboolean
is_up_transition (GtkStackTransitionType transition_type)
{
  return (transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_UP ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_UP);
}

static inline gboolean
is_down_transition (GtkStackTransitionType transition_type)
{
  return (transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_DOWN ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_DOWN);
}

/* Transitions that cause the bin window to move */
static inline gboolean
is_window_moving_transition (GtkStackTransitionType transition_type)
{
  return (transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT ||
          transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_RIGHT ||
          transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_UP ||
          transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_DOWN ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_UP ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_DOWN ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_LEFT ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_RIGHT);
}

/* Transitions that change direction depending on the relative order of the
old and new child */
static inline gboolean
is_direction_dependent_transition (GtkStackTransitionType transition_type)
{
  return (transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT_RIGHT ||
          transition_type == GTK_STACK_TRANSITION_TYPE_SLIDE_UP_DOWN ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_UP_DOWN ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_DOWN_UP ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_LEFT_RIGHT ||
          transition_type == GTK_STACK_TRANSITION_TYPE_OVER_RIGHT_LEFT);
}

/* Returns simple transition type for a direction dependent transition, given
whether the new child (the one being switched to) is first in the stacking order
(added earlier). */
static inline GtkStackTransitionType
get_simple_transition_type (gboolean               new_child_first,
                            GtkStackTransitionType transition_type)
{
  switch (transition_type)
    {
    case GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT_RIGHT:
      return new_child_first ? GTK_STACK_TRANSITION_TYPE_SLIDE_RIGHT : GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT;
    case GTK_STACK_TRANSITION_TYPE_SLIDE_UP_DOWN:
      return new_child_first ? GTK_STACK_TRANSITION_TYPE_SLIDE_DOWN : GTK_STACK_TRANSITION_TYPE_SLIDE_UP;
    case GTK_STACK_TRANSITION_TYPE_OVER_UP_DOWN:
      return new_child_first ? GTK_STACK_TRANSITION_TYPE_UNDER_DOWN : GTK_STACK_TRANSITION_TYPE_OVER_UP;
    case GTK_STACK_TRANSITION_TYPE_OVER_DOWN_UP:
      return new_child_first ? GTK_STACK_TRANSITION_TYPE_UNDER_UP : GTK_STACK_TRANSITION_TYPE_OVER_DOWN;
    case GTK_STACK_TRANSITION_TYPE_OVER_LEFT_RIGHT:
      return new_child_first ? GTK_STACK_TRANSITION_TYPE_UNDER_RIGHT : GTK_STACK_TRANSITION_TYPE_OVER_LEFT;
    case GTK_STACK_TRANSITION_TYPE_OVER_RIGHT_LEFT:
      return new_child_first ? GTK_STACK_TRANSITION_TYPE_UNDER_LEFT : GTK_STACK_TRANSITION_TYPE_OVER_RIGHT;
    default: ;
    }
  return transition_type;
}

static gint
get_bin_window_x (GtkStack            *stack,
                  const GtkAllocation *allocation)
{
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
  int x = 0;

  if (gtk_progress_tracker_get_state (&priv->tracker) != GTK_PROGRESS_STATE_AFTER)
    {
      if (is_left_transition (priv->active_transition_type))
        x = allocation->width * (1 - gtk_progress_tracker_get_ease_out_cubic (&priv->tracker, FALSE));
      if (is_right_transition (priv->active_transition_type))
        x = -allocation->width * (1 - gtk_progress_tracker_get_ease_out_cubic (&priv->tracker, FALSE));
    }

  return x;
}

static gint
get_bin_window_y (GtkStack            *stack,
                  const GtkAllocation *allocation)
{
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
  int y = 0;

  if (gtk_progress_tracker_get_state (&priv->tracker) != GTK_PROGRESS_STATE_AFTER)
    {
      if (is_up_transition (priv->active_transition_type))
        y = allocation->height * (1 - gtk_progress_tracker_get_ease_out_cubic (&priv->tracker, FALSE));
      if (is_down_transition(priv->active_transition_type))
        y = -allocation->height * (1 - gtk_progress_tracker_get_ease_out_cubic (&priv->tracker, FALSE));
    }

  return y;
}

static void
gtk_stack_progress_updated (GtkStack *stack)
{
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  gtk_widget_queue_draw (GTK_WIDGET (stack));

  if (!priv->vhomogeneous || !priv->hhomogeneous)
    gtk_widget_queue_resize (GTK_WIDGET (stack));

  if (priv->bin_window != NULL &&
      is_window_moving_transition (priv->active_transition_type))
    {
      GtkAllocation allocation;
      gtk_widget_get_allocation (GTK_WIDGET (stack), &allocation);
      gdk_window_move (priv->bin_window,
                       get_bin_window_x (stack, &allocation), get_bin_window_y (stack, &allocation));
    }

  if (gtk_progress_tracker_get_state (&priv->tracker) == GTK_PROGRESS_STATE_AFTER)
    {
      if (priv->last_visible_surface != NULL)
        {
          cairo_surface_destroy (priv->last_visible_surface);
          priv->last_visible_surface = NULL;
        }

      if (priv->last_visible_child != NULL)
        {
          gtk_widget_set_child_visible (priv->last_visible_child->widget, FALSE);
          priv->last_visible_child = NULL;
        }
    }
}

static gboolean
gtk_stack_transition_cb (GtkWidget     *widget,
                         GdkFrameClock *frame_clock,
                         gpointer       user_data)
{
  GtkStack *stack = GTK_STACK (widget);
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  if (priv->first_frame_skipped)
    gtk_progress_tracker_advance_frame (&priv->tracker,
                                        gdk_frame_clock_get_frame_time (frame_clock));
  else
    priv->first_frame_skipped = TRUE;

  /* Finish animation early if not mapped anymore */
  if (!gtk_widget_get_mapped (widget))
    gtk_progress_tracker_finish (&priv->tracker);

  gtk_stack_progress_updated (GTK_STACK (widget));

  if (gtk_progress_tracker_get_state (&priv->tracker) == GTK_PROGRESS_STATE_AFTER)
    {
      priv->tick_id = 0;
      g_object_notify_by_pspec (G_OBJECT (stack), stack_props[PROP_TRANSITION_RUNNING]);

      return FALSE;
    }

  return TRUE;
}

static void
gtk_stack_schedule_ticks (GtkStack *stack)
{
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  if (priv->tick_id == 0)
    {
      priv->tick_id =
        gtk_widget_add_tick_callback (GTK_WIDGET (stack), gtk_stack_transition_cb, stack, NULL);
      g_object_notify_by_pspec (G_OBJECT (stack), stack_props[PROP_TRANSITION_RUNNING]);
    }
}

static void
gtk_stack_unschedule_ticks (GtkStack *stack)
{
  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);

  if (priv->tick_id != 0)
    {
      gtk_widget_remove_tick_callback (GTK_WIDGET (stack), priv->tick_id);
      priv->tick_id = 0;
      g_object_notify_by_pspec (G_OBJECT (stack), stack_props[PROP_TRANSITION_RUNNING]);
    }
}

static GtkStackTransitionType
effective_transition_type (GtkStack               *stack,
                           GtkStackTransitionType  transition_type)
{
  if (gtk_widget_get_direction (GTK_WIDGET (stack)) == GTK_TEXT_DIR_RTL)
    {
      switch (transition_type)
        {
        case GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT:
          return GTK_STACK_TRANSITION_TYPE_SLIDE_RIGHT;
        case GTK_STACK_TRANSITION_TYPE_SLIDE_RIGHT:
          return GTK_STACK_TRANSITION_TYPE_SLIDE_LEFT;
        case GTK_STACK_TRANSITION_TYPE_OVER_LEFT:
          return GTK_STACK_TRANSITION_TYPE_OVER_RIGHT;
        case GTK_STACK_TRANSITION_TYPE_OVER_RIGHT:
          return GTK_STACK_TRANSITION_TYPE_OVER_LEFT;
        case GTK_STACK_TRANSITION_TYPE_UNDER_LEFT:
          return GTK_STACK_TRANSITION_TYPE_UNDER_RIGHT;
        case GTK_STACK_TRANSITION_TYPE_UNDER_RIGHT:
          return GTK_STACK_TRANSITION_TYPE_UNDER_LEFT;