path: root/lib/widgets/ephy-spinner.c

/* 
 * Nautilus
 *
 * Copyright (C) 2000 Eazel, Inc.
 * Copyright (C) 2002-2004 Marco Pesenti Gritti
 * Copyright (C) 2004 Christian Persch
 *
 * Nautilus is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Nautilus 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Author: Andy Hertzfeld <andy@eazel.com>
 *
 * Ephy port by Marco Pesenti Gritti <marco@it.gnome.org>
 * 
 * This is the spinner (for busy feedback) for the location bar
 *
 * $Id$
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "ephy-spinner.h"
#include "ephy-debug.h"

#include <gdk-pixbuf/gdk-pixbuf.h>
#include <gtk/gtkicontheme.h>
#include <gtk/gtkiconfactory.h>

/* Spinner cache implementation */

#define EPHY_TYPE_SPINNER_CACHE         (ephy_spinner_cache_get_type())
#define EPHY_SPINNER_CACHE(object)      (G_TYPE_CHECK_INSTANCE_CAST((object), EPHY_TYPE_SPINNER_CACHE, EphySpinnerCache))
#define EPHY_SPINNER_CACHE_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass), EPHY_TYPE_SPINNER_CACHE, EphySpinnerCacheClass))
#define EPHY_IS_SPINNER_CACHE(object)       (G_TYPE_CHECK_INSTANCE_TYPE((object), EPHY_TYPE_SPINNER_CACHE))
#define EPHY_IS_SPINNER_CACHE_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass), EPHY_TYPE_SPINNER_CACHE))
#define EPHY_SPINNER_CACHE_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS((obj), EPHY_TYPE_SPINNER_CACHE, EphySpinnerCacheClass))

typedef struct _EphySpinnerCache    EphySpinnerCache;
typedef struct _EphySpinnerCacheClass   EphySpinnerCacheClass;
typedef struct _EphySpinnerCachePrivate EphySpinnerCachePrivate;
typedef struct _EphySpinnerImages   EphySpinnerImages;

struct _EphySpinnerImages
{
    GtkIconSize size;
    int width;
    int height;
    GdkPixbuf *quiescent_pixbuf;
    GList *images;
};

struct _EphySpinnerCacheClass
{
    GObjectClass parent_class;
};

struct _EphySpinnerCache
{
    GObject parent_object;

    /*< private >*/
    EphySpinnerCachePrivate *priv;
};

#define EPHY_SPINNER_CACHE_GET_PRIVATE(object)(G_TYPE_INSTANCE_GET_PRIVATE ((object), EPHY_TYPE_SPINNER_CACHE, EphySpinnerCachePrivate))

struct _EphySpinnerCachePrivate
{
    GtkIconTheme *icon_theme;
    EphySpinnerImages *originals;
    /* List of EphySpinnerImages scaled to different sizes */
    GList *images;
};

static void ephy_spinner_cache_class_init (EphySpinnerCacheClass *klass);
static void ephy_spinner_cache_init   (EphySpinnerCache *cache);

static GObjectClass *cache_parent_class = NULL;

static GType
ephy_spinner_cache_get_type (void)
{
    static GType type = 0;

    if (type == 0)
    {
        static const GTypeInfo our_info =
        {
            sizeof (EphySpinnerCacheClass),
            NULL,
            NULL,
            (GClassInitFunc) ephy_spinner_cache_class_init,
            NULL,
            NULL,
            sizeof (EphySpinnerCache),
            0,
            (GInstanceInitFunc) ephy_spinner_cache_init
        };

        type = g_type_register_static (G_TYPE_OBJECT,
                           "EphySpinnerCache",
                           &our_info, 0);
    }

    return type;
}

static void
ephy_spinner_images_free (EphySpinnerImages *images)
{
    if (images != NULL)
    {
        g_list_foreach (images->images, (GFunc) g_object_unref, NULL);
        g_object_unref (images->quiescent_pixbuf);

        g_free (images);
    }
}

static EphySpinnerImages *
ephy_spinner_images_copy (EphySpinnerImages *images)
{
    EphySpinnerImages *copy = g_new (EphySpinnerImages, 1);

    copy->size = images->size;
    copy->width = images->width;
    copy->height = images->height;

    copy->quiescent_pixbuf = g_object_ref (images->quiescent_pixbuf);
    copy->images = g_list_copy (images->images);
    g_list_foreach (copy->images, (GFunc) g_object_ref, NULL);

    return copy;
}

static void
ephy_spinner_cache_unload (EphySpinnerCache *cache)
{
    g_list_foreach (cache->priv->images, (GFunc) ephy_spinner_images_free, NULL);
    cache->priv->images = NULL;
    cache->priv->originals = NULL;
}

static GdkPixbuf *
extract_frame (GdkPixbuf *grid_pixbuf,
           int x,
           int y,
           int size)
{
    GdkPixbuf *pixbuf;

    if (x + size > gdk_pixbuf_get_width (grid_pixbuf) ||
        y + size > gdk_pixbuf_get_height (grid_pixbuf))
    {
        return NULL;
    }

    pixbuf = gdk_pixbuf_new_subpixbuf (grid_pixbuf,
                       x, y,
                       size, size);
    g_return_val_if_fail (pixbuf != NULL, NULL);

    return pixbuf;
}

static void
ephy_spinner_cache_load (EphySpinnerCache *cache)
{
    EphySpinnerImages *images;
    GdkPixbuf *icon_pixbuf, *pixbuf;
    GtkIconInfo *icon_info;
    int grid_width, grid_height, x, y, size, h, w;
    const char *icon;

    LOG ("EphySpinnerCache loading")

    ephy_spinner_cache_unload (cache);

    START_PROFILER ("loading spinner animation")

    /* Load the animation */
    icon_info = gtk_icon_theme_lookup_icon (cache->priv->icon_theme,
                        "gnome-spinner", -1, 0);
    if (icon_info == NULL)
    {
        STOP_PROFILER ("loading spinner animation")

        g_warning ("Throbber animation not found\n");
        return;
    }

    size = gtk_icon_info_get_base_size (icon_info);
    icon = gtk_icon_info_get_filename (icon_info);
    g_return_if_fail (icon != NULL);

    icon_pixbuf = gdk_pixbuf_new_from_file (icon, NULL);
    if (icon_pixbuf == NULL)
    {
        STOP_PROFILER ("loading spinner animation")

        g_warning ("Could not load the spinner file\n");
        gtk_icon_info_free (icon_info);
        return;
    }

    grid_width = gdk_pixbuf_get_width (icon_pixbuf);
    grid_height = gdk_pixbuf_get_height (icon_pixbuf);

    images = g_new (EphySpinnerImages, 1);
    cache->priv->images = g_list_prepend (NULL, images);
    cache->priv->originals = images;

    images->size = GTK_ICON_SIZE_INVALID;
    images->width = images->height = size;
    images->images = NULL;
    images->quiescent_pixbuf = NULL;

    for (y = 0; y < grid_height; y += size)
    {
        for (x = 0; x < grid_width ; x += size)
        {
            pixbuf = extract_frame (icon_pixbuf, x, y, size);

            if (pixbuf)
            {
                images->images =
                    g_list_prepend (images->images, pixbuf);
            }
            else
            {
                g_warning ("Cannot extract frame from the grid\n");
            }
        }
    }
    images->images = g_list_reverse (images->images);

    gtk_icon_info_free (icon_info);
    g_object_unref (icon_pixbuf);

    /* Load the rest icon */
    icon_info = gtk_icon_theme_lookup_icon (cache->priv->icon_theme,
                        "gnome-spinner-rest", -1, 0);
    if (icon_info == NULL)
    {
        STOP_PROFILER ("loading spinner animation")

        g_warning ("Throbber rest icon not found\n");
        return;
    }

    size = gtk_icon_info_get_base_size (icon_info);
    icon = gtk_icon_info_get_filename (icon_info);
    g_return_if_fail (icon != NULL);

    icon_pixbuf = gdk_pixbuf_new_from_file (icon, NULL);
    gtk_icon_info_free (icon_info);

    if (icon_pixbuf == NULL)
    {
        STOP_PROFILER ("loading spinner animation")

        g_warning ("Could not load spinner rest icon\n");
        ephy_spinner_images_free (images);
        return;
    }

    images->quiescent_pixbuf = icon_pixbuf;

    w = gdk_pixbuf_get_width (icon_pixbuf);
    h = gdk_pixbuf_get_height (icon_pixbuf);
    images->width = MAX (images->width, w);
    images->height = MAX (images->height, h);

    STOP_PROFILER ("loading spinner animation")
}

static int
compare_size (gconstpointer images_ptr,
          gconstpointer size_ptr)
{
    const EphySpinnerImages *images = (const EphySpinnerImages *) images_ptr;
    GtkIconSize size = GPOINTER_TO_INT (size_ptr);

    if (images->size == size)
    {
        return 0;
    }

    return -1;
}

static GdkPixbuf *
scale_to_size (GdkPixbuf *pixbuf,
           int dw,
           int dh)
{
    GdkPixbuf *result;
    int pw, ph;

    pw = gdk_pixbuf_get_width (pixbuf);
    ph = gdk_pixbuf_get_height (pixbuf);

    if (pw != dw || ph != dh)
    {
        result = gdk_pixbuf_scale_simple (pixbuf, dw, dh,
                          GDK_INTERP_BILINEAR);
    }
    else
    {
        result = g_object_ref (pixbuf);
    }

    return result;
}

static EphySpinnerImages *
ephy_spinner_cache_get_images (EphySpinnerCache *cache,
                   GtkIconSize size)
{
    EphySpinnerImages *images;
    GdkPixbuf *pixbuf, *scaled_pixbuf;
    GList *element, *l;
    int h, w;

    LOG ("Getting animation images at size %d", size)

    if (cache->priv->images == NULL || cache->priv->originals == NULL)
    {
        return NULL;
    }

    element = g_list_find_custom (cache->priv->images,
                      GINT_TO_POINTER (size),
                      (GCompareFunc) compare_size);
    if (element != NULL)
    {
        return ephy_spinner_images_copy ((EphySpinnerImages *) element->data);
    }

    if (!gtk_icon_size_lookup (size, &w, &h))
    {
        g_warning ("Failed to lookup icon size\n");
        return NULL;
    }

    images = g_new (EphySpinnerImages, 1);
    images->size = size;
    images->width = w;
    images->height = h;
    images->images = NULL;

    START_PROFILER ("scaling spinner animation")

    for (l = cache->priv->originals->images; l != NULL; l = l->next)
    {
        pixbuf = (GdkPixbuf *) l->data;
        scaled_pixbuf = scale_to_size (pixbuf, w, h);

        images->images = g_list_prepend (images->images, scaled_pixbuf);
    }
    images->images = g_list_reverse (images->images);

    images->quiescent_pixbuf =
        scale_to_size (cache->priv->originals->quiescent_pixbuf, w, h);

    /* store in cache */
    cache->priv->images = g_list_prepend (cache->priv->images, images);

    STOP_PROFILER ("scaling spinner animation")

    return ephy_spinner_images_copy (images);
}

static void
ephy_spinner_cache_init (EphySpinnerCache *cache)
{
    cache->priv = EPHY_SPINNER_CACHE_GET_PRIVATE (cache);

    LOG ("EphySpinnerCache initialising")

    /* FIXME: icon theme is per-screen, not global */
    cache->priv->icon_theme = gtk_icon_theme_get_default ();
    g_signal_connect_swapped (cache->priv->icon_theme, "changed",
                  G_CALLBACK (ephy_spinner_cache_load), cache);

    ephy_spinner_cache_load (cache);
}

static void
ephy_spinner_cache_finalize (GObject *object)
{
    EphySpinnerCache *cache = EPHY_SPINNER_CACHE (object); 

    LOG ("EphySpinnerCache finalising")

    g_signal_handlers_disconnect_by_func
        (cache->priv->icon_theme, G_CALLBACK(ephy_spinner_cache_load), cache);

    ephy_spinner_cache_unload (cache);

    G_OBJECT_CLASS (cache_parent_class)->finalize (object);
}

static void
ephy_spinner_cache_class_init (EphySpinnerCacheClass *klass)
{
    GObjectClass *object_class = G_OBJECT_CLASS (klass);

    cache_parent_class = g_type_class_peek_parent (klass);

    object_class->finalize = ephy_spinner_cache_finalize;

    g_type_class_add_private (object_class, sizeof (EphySpinnerCachePrivate));
}

static EphySpinnerCache *spinner_cache = NULL;

static EphySpinnerCache *
ephy_spinner_cache_ref (void)
{
    if (spinner_cache == NULL)
    {
        EphySpinnerCache **cache_ptr;

        spinner_cache = g_object_new (EPHY_TYPE_SPINNER_CACHE, NULL);
        cache_ptr = &spinner_cache;
        g_object_add_weak_pointer (G_OBJECT (spinner_cache),
                       (gpointer *) cache_ptr);

        return spinner_cache;
    }
    else
    {
        return g_object_ref (spinner_cache);
    }
}

/* Spinner implementation */

#define SPINNER_TIMEOUT 100 /* Milliseconds Per Frame */

#define EPHY_SPINNER_GET_PRIVATE(object)(G_TYPE_INSTANCE_GET_PRIVATE ((object), EPHY_TYPE_SPINNER, EphySpinnerDetails))

struct EphySpinnerDetails
{
    GtkIconTheme *icon_theme;
    EphySpinnerCache *cache;
    GtkIconSize size;
    EphySpinnerImages *images;
    GList *current_image;
    guint timer_task;
};

static void ephy_spinner_class_init (EphySpinnerClass *class);
static void ephy_spinner_init       (EphySpinner *spinner);

static GObjectClass *parent_class = NULL;

GType
ephy_spinner_get_type (void)
{
    static GType type = 0;

    if (type == 0)
    {
        static const GTypeInfo our_info =
        {
            sizeof (EphySpinnerClass),
            NULL, /* base_init */
            NULL, /* base_finalize */
            (GClassInitFunc) ephy_spinner_class_init,
            NULL,
            NULL, /* class_data */
            sizeof (EphySpinner),
            0, /* n_preallocs */
            (GInstanceInitFunc) ephy_spinner_init
        };

        type = g_type_register_static (GTK_TYPE_EVENT_BOX,
                           "EphySpinner",
                           &our_info, 0);
    }

    return type;
}

static gboolean
ephy_spinner_load_images (EphySpinner *spinner)
{
    EphySpinnerDetails *details = spinner->details;

    if (details->images == NULL)
    {
        START_PROFILER ("ephy_spinner_load_images")

        details->images =
            ephy_spinner_cache_get_images (details->cache, details->size);

        if (details->images != NULL)
        {
            details->current_image = details->images->images;
        }

        STOP_PROFILER ("ephy_spinner_load_images")
    }

    return details->images != NULL;
}

static void
ephy_spinner_unload_images (EphySpinner *spinner)
{
    ephy_spinner_images_free (spinner->details->images);
    spinner->details->images = NULL;
    spinner->details->current_image = NULL;
}

static void
icon_theme_changed_cb (GtkIconTheme *icon_theme,
               EphySpinner *spinner)
{
    ephy_spinner_unload_images (spinner);
    gtk_widget_queue_resize (GTK_WIDGET (spinner));
}

static void
ephy_spinner_init (EphySpinner *spinner)
{
    GtkWidget *widget = GTK_WIDGET (spinner);

    gtk_widget_set_events (widget,
                   gtk_widget_get_events (widget)
                   | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK
                   | GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK);

    spinner->details = EPHY_SPINNER_GET_PRIVATE (spinner);

    spinner->details->cache = ephy_spinner_cache_ref ();
    spinner->details->size = GTK_ICON_SIZE_INVALID;

    /* FIXME: icon theme is per-screen, not global */
    spinner->details->icon_theme = gtk_icon_theme_get_default ();
    g_signal_connect (spinner->details->icon_theme, "changed",
              G_CALLBACK (icon_theme_changed_cb), spinner);

}

static GdkPixbuf *
select_spinner_image (EphySpinner *spinner)
{
    EphySpinnerDetails *details = spinner->details;
    EphySpinnerImages *images = details->images;

    g_return_val_if_fail (images != NULL, NULL);

    if (spinner->details->timer_task == 0)
    {
        if (images->quiescent_pixbuf != NULL)
        {
            return g_object_ref (details->images->quiescent_pixbuf);
        }

        return NULL;
    }

    g_return_val_if_fail (details->current_image != NULL, NULL);

    return g_object_ref (details->current_image->data);
}

static int
ephy_spinner_expose (GtkWidget *widget,
             GdkEventExpose *event)
{
    EphySpinner *spinner = EPHY_SPINNER (widget);
    GdkPixbuf *pixbuf;
    GdkGC *gc;
    int x_offset, y_offset, width, height;
    GdkRectangle pix_area, dest;

    if (!GTK_WIDGET_DRAWABLE (spinner))
    {
        return TRUE;
    }

    if (!ephy_spinner_load_images (spinner))
    {
        return TRUE;
    }

    pixbuf = select_spinner_image (spinner);
    if (pixbuf == NULL)
    {
        return FALSE;
    }

    width = gdk_pixbuf_get_width (pixbuf);
    height = gdk_pixbuf_get_height (pixbuf);

    /* Compute the offsets for the image centered on our allocation */
    x_offset = (widget->allocation.width - width) / 2;
    y_offset = (widget->allocation.height - height) / 2;

    pix_area.x = x_offset + widget->allocation.x;
    pix_area.y = y_offset + widget->allocation.y;
    pix_area.width = width;
    pix_area.height = height;

    if (!gdk_rectangle_intersect (&event->area, &pix_area, &dest))
    {
        g_object_unref (pixbuf);
        return FALSE;
    }

    gc = gdk_gc_new (widget->window);
    gdk_draw_pixbuf (widget->window, gc, pixbuf,
             dest.x - x_offset - widget->allocation.x,
             dest.y - y_offset - widget->allocation.y,
             dest.x, dest.y,
             dest.width, dest.height,
             GDK_RGB_DITHER_MAX, 0, 0);
    g_object_unref (gc);

    g_object_unref (pixbuf);

    return FALSE;
}

static gboolean
bump_spinner_frame_cb (EphySpinner *spinner)
{
    GList *frame;

    if (!GTK_WIDGET_DRAWABLE (spinner))
    {
        return TRUE;
    }

    frame = spinner->details->current_image;

    if (g_list_next (frame) != NULL)
    {
        frame = frame->next;
    }
    else
    {
        frame = g_list_first (frame);
    }

    spinner->details->current_image = frame;

    gtk_widget_queue_draw (GTK_WIDGET (spinner));

    /* run again */
    return TRUE;
}

/**
 * ephy_spinner_start:
 * @spinner: a #EphySpinner
 *
 * Start the spinner animation.
 **/
void
ephy_spinner_start (EphySpinner *spinner)
{
    if (spinner->details->timer_task == 0)
    {

        if (spinner->details->images != NULL)
        {
            /* reset to first frame */
            spinner->details->current_image =
                spinner->details->images->images;
        }

        spinner->details->timer_task =
            g_timeout_add (SPINNER_TIMEOUT,
                       (GSourceFunc) bump_spinner_frame_cb,
                       spinner);
    }
}

static void
ephy_spinner_remove_update_callback (EphySpinner *spinner)
{
    if (spinner->details->timer_task != 0)
    {
        g_source_remove (spinner->details->timer_task);
        spinner->details->timer_task = 0;
    }
}

/**
 * ephy_spinner_stop:
 * @spinner: a #EphySpinner
 *
 * Stop the spinner animation.
 **/
void
ephy_spinner_stop (EphySpinner *spinner)
{
    if (spinner->details->timer_task != 0)
    {
        ephy_spinner_remove_update_callback (spinner);
        gtk_widget_queue_draw (GTK_WIDGET (spinner));
    }
}

/*
 * ephy_spinner_set_size:
 * @spinner: a #EphySpinner
 * @size: the size of type %GtkIconSize
 *
 * Set the size of the spinner. Use %GTK_ICON_SIZE_INVALID to use the
 * native size of the icons.
 **/
void
ephy_spinner_set_size (EphySpinner *spinner,
               GtkIconSize size)
{
    if (size != spinner->details->size)
    {
        ephy_spinner_unload_images (spinner);

        spinner->details->size = size;

        gtk_widget_queue_resize (GTK_WIDGET (spinner));
    }
}

static void
ephy_spinner_size_request (GtkWidget *widget,
               GtkRequisition *requisition)
{
    EphySpinner *spinner = EPHY_SPINNER (widget);

    if (!ephy_spinner_load_images (spinner))
    {
        requisition->width = requisition->height = 0;
        gtk_icon_size_lookup (spinner->details->size,
                      &requisition->width,
                      &requisition->height);
        return;
    }

    requisition->width = spinner->details->images->width;
    requisition->height = spinner->details->images->height;

    /* allocate some extra margin so we don't butt up against toolbar edges */
    if (spinner->details->size != GTK_ICON_SIZE_MENU)
    {
        requisition->width += 4;
        requisition->height += 4;
    }
}

static void
ephy_spinner_finalize (GObject *object)
{
    EphySpinner *spinner = EPHY_SPINNER (object);

    g_signal_handlers_disconnect_by_func
        (spinner->details->icon_theme,
         G_CALLBACK (icon_theme_changed_cb), spinner);

    ephy_spinner_remove_update_callback (spinner);
    ephy_spinner_unload_images (spinner);

    g_object_unref (spinner->details->cache);

    G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
ephy_spinner_class_init (EphySpinnerClass *class)
{
    GObjectClass *object_class =  G_OBJECT_CLASS (class);
    GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);

    parent_class = g_type_class_peek_parent (class);

    object_class->finalize = ephy_spinner_finalize;

    widget_class->expose_event = ephy_spinner_expose;
    widget_class->size_request = ephy_spinner_size_request;

    g_type_class_add_private (object_class, sizeof (EphySpinnerDetails));
}

/*
 * ephy_spinner_new:
 *
 * Create a new #EphySpinner. The spinner is a widget
 * that gives the user feedback about network status with
 * an animated image.
 *
 * Return Value: the spinner #GtkWidget
 **/
GtkWidget *
ephy_spinner_new (void)
{
    return GTK_WIDGET (g_object_new (EPHY_TYPE_SPINNER,
                     "visible-window", FALSE,
                     NULL));
}