gnome-shell/src/st/st-theme-node.h

/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
#ifndef __ST_THEME_NODE_H__
#define __ST_THEME_NODE_H__

#include <clutter/clutter.h>
#include "st-theme-image.h"

G_BEGIN_DECLS

/**
 * SECTION:StThemeNode
 * @short_description: style information for one node in a tree of themed objects
 *
 * A #StThemeNode represents the CSS style information (the set of CSS properties) for one
 * node in a tree of themed objects. In typical usage, it represents the style information
 * for a single #ClutterActor. A #StThemeNode is immutable: attributes such as the
 * CSS classes for the node are passed in at construction. If the attributes of the node
 * or any parent node change, the node should be discarded and a new node created.
 * #StThemeNode has generic accessors to look up properties by name and specific
 * accessors for standard CSS properties that add caching and handling of various
 * details of the CSS specification. #StThemeNode also has convenience functions to help
 * in implementing a #ClutterActor with borders and padding.
 */

typedef struct _StTheme          StTheme;
typedef struct _StThemeContext   StThemeContext;

typedef struct _StThemeNode      StThemeNode;
typedef struct _StThemeNodeClass StThemeNodeClass;

#define ST_TYPE_THEME_NODE              (st_theme_node_get_type ())
#define ST_THEME_NODE(object)           (G_TYPE_CHECK_INSTANCE_CAST ((object), ST_TYPE_THEME_NODE, StThemeNode))
#define ST_THEME_NODE_CLASS(klass)      (G_TYPE_CHECK_CLASS_CAST ((klass),     ST_TYPE_THEME_NODE, StThemeNodeClass))
#define ST_IS_THEME_NODE(object)        (G_TYPE_CHECK_INSTANCE_TYPE ((object), ST_TYPE_THEME_NODE))
#define ST_IS_THEME_NODE_CLASS(klass)   (G_TYPE_CHECK_CLASS_TYPE ((klass),     ST_TYPE_THEME_NODE))
#define ST_THEME_NODE_GET_CLASS(obj)    (G_TYPE_INSTANCE_GET_CLASS ((obj),     ST_TYPE_THEME_NODE, StThemeNodeClass))

typedef enum {
    ST_SIDE_TOP,
    ST_SIDE_RIGHT,
    ST_SIDE_BOTTOM,
    ST_SIDE_LEFT
} StSide;

typedef enum {
    ST_CORNER_TOPLEFT,
    ST_CORNER_TOPRIGHT,
    ST_CORNER_BOTTOMRIGHT,
    ST_CORNER_BOTTOMLEFT
} StCorner;

/* These are the CSS values; that doesn't mean we have to implement blink... */
typedef enum {
    ST_TEXT_DECORATION_UNDERLINE    = 1 << 0,
    ST_TEXT_DECORATION_OVERLINE     = 1 << 1,
    ST_TEXT_DECORATION_LINE_THROUGH = 1 << 2,
    ST_TEXT_DECORATION_BLINK        = 1 << 3
} StTextDecoration;

GType st_theme_node_get_type (void) G_GNUC_CONST;

StThemeNode *st_theme_node_new (StThemeContext *context,
                                StThemeNode    *parent_node,   /* can be null */
                                StTheme        *theme,         /* can be null */
                                GType           element_type,
                                const char     *element_id,
                                const char     *element_class,
                                const char     *pseudo_class,
                                const char     *inline_style);

StThemeNode *st_theme_node_get_parent (StThemeNode *node);

StTheme *st_theme_node_get_theme (StThemeNode *node);

GType       st_theme_node_get_element_type  (StThemeNode *node);
const char *st_theme_node_get_element_id    (StThemeNode *node);
const char *st_theme_node_get_element_class (StThemeNode *node);
const char *st_theme_node_get_pseudo_class  (StThemeNode *node);

/* Generic getters ... these are not cached so are less efficient. The other
 * reason for adding the more specific version is that we can handle the
 * details of the actual CSS rules, which can be complicated, especially
 * for fonts
 */
gboolean st_theme_node_get_color  (StThemeNode  *node,
                                   const char   *property_name,
                                   gboolean      inherit,
                                   ClutterColor *color);

gboolean st_theme_node_get_double (StThemeNode  *node,
                                   const char   *property_name,
                                   gboolean      inherit,
                                   double       *value);

gboolean st_theme_node_get_length (StThemeNode *node,
                                   const char  *property_name,
                                   gboolean     inherit,
                                   gdouble     *length);

/* Specific getters for particular properties: cached
 */
void st_theme_node_get_background_color (StThemeNode  *node,
                                         ClutterColor *color);
void st_theme_node_get_foreground_color (StThemeNode  *node,
                                         ClutterColor *color);

const char *st_theme_node_get_background_image (StThemeNode *node);

double st_theme_node_get_border_width  (StThemeNode  *node,
                                        StSide        side);
double st_theme_node_get_border_radius (StThemeNode  *node,
                                        StCorner      corner);
void   st_theme_node_get_border_color  (StThemeNode  *node,
                                        StSide        side,
                                        ClutterColor *color);

double st_theme_node_get_padding       (StThemeNode  *node,
                                        StSide        side);

StTextDecoration st_theme_node_get_text_decoration (StThemeNode *node);

/* Font rule processing is pretty complicated, so we just hardcode it
 * under the standard font/font-family/font-size/etc names. This means
 * you can't have multiple separate styled fonts for a single item,
 * but that should be OK.
 */
const PangoFontDescription *st_theme_node_get_font (StThemeNode *node);

/* This is the getter for -st-background-image, which is different from
 * background-image in having provisions for unscaled borders.
 */
StThemeImage *st_theme_node_get_background_theme_image (StThemeNode *node);

G_END_DECLS

#endif /* __ST_THEME_NODE_H__ */