/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-

   eel-background.h: Object for the background of a widget.

   Copyright (C) 2000 Eazel, Inc.
   Copyright (C) 2012 Jasmine Hassan <jasmine.aura@gmail.com>

   This program 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 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library 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.

   Authors: Darin Adler <darin@eazel.com>
            Jasmine Hassan <jasmine.aura@gmail.com>
*/

#ifndef EEL_BACKGROUND_H
#define EEL_BACKGROUND_H

/* Windows for Eel can contain backgrounds that are either tiled
   with an image, a solid color, or a color gradient. This class manages
   the process of loading the image if necessary and parsing the string
   that specifies either a color or color gradient.

   The color or gradient is always present, even if there's a tiled image
   on top of it. This is used when the tiled image can't be loaded for
   some reason (or just has not been loaded yet).

   The EelBackground object is easier to modify than a GtkStyle.
   You can just call eel_get_window_background and modify the
   returned background directly, unlike a style, which must be copied,
   modified and then set.
*/

#include <gdk/gdk.h>
#include <gtk/gtk.h>

#include <gdk-pixbuf/gdk-pixbuf.h>

#define MATE_DESKTOP_USE_UNSTABLE_API
#include <libmate-desktop/mate-bg.h>

typedef struct EelBackground EelBackground;
typedef struct EelBackgroundClass EelBackgroundClass;

#define EEL_TYPE_BACKGROUND eel_background_get_type()
#define EEL_BACKGROUND(obj) \
  (G_TYPE_CHECK_INSTANCE_CAST ((obj), EEL_TYPE_BACKGROUND, EelBackground))
#define EEL_BACKGROUND_CLASS(klass) \
  (G_TYPE_CHECK_CLASS_CAST ((klass), EEL_TYPE_BACKGROUND, EelBackgroundClass))
#define EEL_IS_BACKGROUND(obj) \
  (G_TYPE_CHECK_INSTANCE_TYPE ((obj), EEL_TYPE_BACKGROUND))
#define EEL_IS_BACKGROUND_CLASS(klass) \
  (G_TYPE_CHECK_CLASS_TYPE ((klass), EEL_TYPE_BACKGROUND))
#define EEL_BACKGROUND_GET_CLASS(obj) \
  (G_TYPE_INSTANCE_GET_CLASS ((obj), EEL_TYPE_BACKGROUND, EelBackgroundClass))

GType                       eel_background_get_type              (void);
EelBackground *             eel_background_new                   (void);


/* Calls to change a background. */
void                        eel_background_set_use_base          (EelBackground   *self,
        							  gboolean         use_base);
void                        eel_background_set_color             (EelBackground   *self,
        							  const gchar     *color_or_gradient);
void                        eel_background_set_image_uri         (EelBackground   *self,
        							  const gchar      *image_uri);
void                        eel_background_reset                 (EelBackground   *self);
void                        eel_bg_set_placement                 (EelBackground   *self,
        							  MateBGPlacement  placement);

/* Should be TRUE for desktop background */
gboolean		    eel_background_is_desktop 		 (EelBackground   *self);
void			    eel_background_set_desktop 		 (EelBackground   *self,
        							  GtkWidget       *widget,
        							  gboolean         is_desktop);

/* Calls to interrogate the current state of a background. */
gchar *                     eel_bg_get_desktop_color             (EelBackground   *self);
gchar *                     eel_background_get_color             (EelBackground   *self);
gchar *                     eel_background_get_image_uri         (EelBackground   *self);
gboolean                    eel_background_is_dark               (EelBackground   *self);
gboolean                    eel_background_is_set                (EelBackground   *self);

/* Helper function for widgets using EelBackground */
void                        eel_background_draw                  (GtkWidget       *widget,
#if GTK_CHECK_VERSION (3, 0, 0)
        							  cairo_t         *cr);
#else
        							  GdkEventExpose  *event);
#endif

/* Handles a dragged color being dropped on a widget to change the background color. */
void                        eel_background_set_dropped_color     (EelBackground   *self,
        							  GtkWidget       *widget,
        							  GdkDragAction    action,
        							  int              drop_location_x,
        							  int              drop_location_y,
        							  const GtkSelectionData
        							                  *dropped_color);

/* Handles a special-case image name that means "reset to default background" too. */
void                        eel_background_set_dropped_image     (EelBackground   *self,
        							  GdkDragAction    action,
        							  const gchar     *image_uri);

/* Gets or creates a background so that it's attached to a widget. */
EelBackground *             eel_get_widget_background            (GtkWidget       *widget);

/* Thin-wrappers around mate_bg gsettings functions */
void			    eel_bg_save_to_gsettings             (EelBackground   *self,
								  GSettings       *settings);
void			    eel_bg_load_from_gsettings           (EelBackground   *self,
								  GSettings       *settings);
void			    eel_bg_load_from_system_gsettings    (EelBackground   *self,
								  GSettings       *settings,
								  gboolean         apply);

/* Set bg's activity status. Inactive backgrounds are drawn in the theme's INSENSITIVE color. */
void                        eel_background_set_active            (EelBackground   *self,
        							  gboolean         is_active);

typedef struct EelBackgroundDetails EelBackgroundDetails;

struct EelBackground
{
    GObject object;
    EelBackgroundDetails *details;
};

struct EelBackgroundClass
{
    GObjectClass parent_class;

    /* This signal is emitted whenever the background settings are
     * changed.
     */
    void (* settings_changed) (EelBackground *);

    /* This signal is emitted whenever the appearance of the
     * background has changed, like when the background settings are
     * altered or when an image is loaded.
     */
    void (* appearance_changed) (EelBackground *);

    /* This signal is emitted when image loading is over - whether it
     * was successfully loaded or not.
     */
    void (* image_loading_done) (EelBackground *self, gboolean successful_load);

    /* This signal is emitted when the background is reset by receiving
       the reset property from a drag
     */
    void (* reset) (EelBackground *);

};

#endif /* EEL_BACKGROUND_H */