#ifndef SCROLL_AREA_H
#define SCROLL_AREA_H

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

#define FOO_TYPE_SCROLL_AREA            (foo_scroll_area_get_type ())
#define FOO_SCROLL_AREA(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), FOO_TYPE_SCROLL_AREA, FooScrollArea))
#define FOO_SCROLL_AREA_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass),  FOO_TYPE_SCROLL_AREA, FooScrollAreaClass))
#define FOO_IS_SCROLL_AREA(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), FOO_TYPE_SCROLL_AREA))
#define FOO_IS_SCROLL_AREA_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass),  FOO_TYPE_SCROLL_AREA))
#define FOO_SCROLL_AREA_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj),  FOO_TYPE_SCROLL_AREA, FooScrollAreaClass))

typedef struct FooScrollArea FooScrollArea;
typedef struct FooScrollAreaClass FooScrollAreaClass;
typedef struct FooScrollAreaPrivate FooScrollAreaPrivate;
typedef struct FooScrollAreaEvent FooScrollAreaEvent;

typedef enum
{
    FOO_NONE,
    FOO_BUTTON_PRESS,
    FOO_BUTTON_RELEASE,
    FOO_ENTER,
    FOO_LEAVE,
    FOO_MOTION
} FooScrollAreaEventType;

struct FooScrollAreaEvent
{
    FooScrollAreaEventType	type;
    int				x;
    int				y;
    int				button;
};

typedef void (* FooScrollAreaEventFunc) (FooScrollArea      *area,
					 FooScrollAreaEvent *event,
					 gpointer            data);

struct FooScrollArea
{
    GtkContainer parent_instance;

    FooScrollAreaPrivate *priv;
};

struct FooScrollAreaClass
{
    GtkContainerClass parent_class;

    void (*set_scroll_adjustments) (FooScrollArea *scroll_area,
				    GtkAdjustment *hadjustment,
				    GtkAdjustment *vadjustment);

    void (*viewport_changed) (FooScrollArea *scroll_area,
			      GdkRectangle  *viewport,
			      GdkRectangle  *old_viewport);

    void (*viewport_size_changed) (FooScrollArea *scroll_area,
				   GdkRectangle  *viewport,
				   GdkRectangle  *old_viewport);

    void (*paint) (FooScrollArea *scroll_area,
		   cairo_t       *cr,
		   GdkRectangle  *extents,
		   GdkRegion     *region);
};

GType          foo_scroll_area_get_type              (void);
FooScrollArea *foo_scroll_area_new                   (void);


/* Resizing
 */
/* Set the requisition for the widget. */
void           foo_scroll_area_set_min_size          (FooScrollArea          *scroll_area,
						      int                     min_width,
						      int                     min_height);

/* Set how much of the canvas can be scrolled into view */
void           foo_scroll_area_set_size              (FooScrollArea          *scroll_area,
						      int                     width,
						      int                     height);
void           foo_scroll_area_set_size_fixed_y      (FooScrollArea          *scroll_area,
						      int                     width,
						      int                     height,
						      int                     old_y,
						      int                     new_y);
void           foo_scroll_area_set_viewport_pos      (FooScrollArea          *scroll_area,
						      int                     x,
						      int                     y);
void           foo_scroll_area_get_viewport          (FooScrollArea          *scroll_area,
						      GdkRectangle           *viewport);

/* When the viewport_{size}_changed signals are emitted, this can be
 * called to determine if the viewport change happened as a result of
 * a resize. (Looking at the old and new size is insufficient because
 * resizing may cause more than one viewport change.
 */
gboolean       foo_scroll_area_is_resizing           (FooScrollArea          *scroll_area);

/* Input
 */
void           foo_scroll_area_add_input_from_stroke (FooScrollArea          *scroll_area,
						      cairo_t                *cr,
						      FooScrollAreaEventFunc  func,
						      gpointer                data);
void           foo_scroll_area_add_input_from_fill   (FooScrollArea          *scroll_area,
						      cairo_t                *cr,
						      FooScrollAreaEventFunc  func,
						      gpointer                data);

/* Invalidate
 */
void           foo_scroll_area_invalidate_region     (FooScrollArea          *area,
						      GdkRegion              *region);
void           foo_scroll_area_invalidate            (FooScrollArea          *scroll_area);
void           foo_scroll_area_invalidate_rect       (FooScrollArea          *scroll_area,
						      int                     x,
						      int                     y,
						      int                     width,
						      int                     height);

/* Grabbing
 */
void           foo_scroll_area_begin_grab            (FooScrollArea          *scroll_area,
						      FooScrollAreaEventFunc  func,
						      gpointer                input_data);
void           foo_scroll_area_end_grab              (FooScrollArea          *scroll_area);
gboolean       foo_scroll_area_is_grabbed            (FooScrollArea          *scroll_area);

/* Auto scroll
 */
void           foo_scroll_area_begin_auto_scroll     (FooScrollArea          *scroll_area);
void           foo_scroll_area_auto_scroll           (FooScrollArea          *scroll_area,
						      FooScrollAreaEvent     *event);
void           foo_scroll_area_end_auto_scroll       (FooScrollArea          *scroll_area);


/* Debug */
void	       foo_scroll_area_set_paint_updates     (FooScrollArea          *scroll_area,
						      gboolean                paint_upd);


#endif