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

/* eel-eel-gtk-extensions.c - Access gtk/gdk attributes as libeel rectangles.

   Copyright (C) 2000 Eazel, Inc.

   The Mate Library 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.

   The Mate Library 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 PEELICULAR 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 the Mate Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
   Boston, MA 02110-1301, USA.

   Authors: Ramiro Estrugo <ramiro@eazel.com>
*/

#include <config.h>

#include "eel-art-gtk-extensions.h"
#include <gdk/gdkx.h>

/**
 * eel_gdk_rectangle_to_eel_irect:
 * @gdk_rectangle: The source GdkRectangle.
 *
 * Return value: An EelIRect representation of the GdkRectangle.
 *
 * This is a very simple conversion of rectangles from the Gdk to the Libeel
 * universe.  This is useful in code that does clipping (or other operations)
 * using libeel and has a GdkRectangle to work with - for example expose_event()
 * in GtkWidget's.
 */
EelIRect
eel_gdk_rectangle_to_eel_irect (GdkRectangle gdk_rectangle)
{
    EelIRect rectangle;

    rectangle.x0 = gdk_rectangle.x;
    rectangle.y0 = gdk_rectangle.y;
    rectangle.x1 = rectangle.x0 + (int) gdk_rectangle.width;
    rectangle.y1 = rectangle.y0 + (int) gdk_rectangle.height;

    return rectangle;
}

/**
 * eel_screen_get_dimensions:
 *
 * Return value: The screen dimensions.
 *
 */
EelDimensions
eel_screen_get_dimensions (void)
{
    EelDimensions screen_dimensions;

    screen_dimensions.width = gdk_screen_width ();
    screen_dimensions.height = gdk_screen_height ();

    g_assert (screen_dimensions.width > 0);
    g_assert (screen_dimensions.height > 0);

    return screen_dimensions;
}

/**
 * eel_gdk_window_get_bounds:
 * @gdk_window: The source GdkWindow.
 *
 * Return value: An EelIRect representation of the given GdkWindow's geometry
 * relative to its parent in the Gdk window hierarchy.
 *
 */
EelIRect
eel_gdk_window_get_bounds (GdkWindow *gdk_window)
{
    EelIRect bounds;
    int width;
    int height;

    g_return_val_if_fail (gdk_window != NULL, eel_irect_empty);

    gdk_window_get_position (gdk_window, &bounds.x0, &bounds.y0);

    width = gdk_window_get_width(gdk_window);
    height = gdk_window_get_height(gdk_window);

    bounds.x1 = bounds.x0 + width;
    bounds.y1 = bounds.y0 + height;

    return bounds;
}

/**
 * eel_gdk_window_get_bounds:
 * @gdk_window: The source GdkWindow.
 *
 * Return value: An EelIRect representation of the given GdkWindow's geometry
 * relative to the screen.
 *
 */
EelIRect
eel_gdk_window_get_screen_relative_bounds (GdkWindow *gdk_window)
{
    EelIRect screen_bounds;
    int width;
    int height;

    g_return_val_if_fail (gdk_window != NULL, eel_irect_empty);

    if (!gdk_window_get_origin (gdk_window,
                                &screen_bounds.x0,
                                &screen_bounds.y0))
    {
        return eel_irect_empty;
    }

    width = gdk_window_get_width(gdk_window);
    height = gdk_window_get_height(gdk_window);

    screen_bounds.x1 = screen_bounds.x0 + width;
    screen_bounds.y1 = screen_bounds.y0 + height;

    return screen_bounds;
}

/**
 * eel_gtk_widget_get_bounds:
 * @gtk_widget: The source GtkWidget.
 *
 * Return value: An EelIRect representation of the given GtkWidget's geometry
 * relative to its parent.  In the Gtk universe this is known as "allocation."
 *
 */
EelIRect
eel_gtk_widget_get_bounds (GtkWidget *gtk_widget)
{
    GtkAllocation allocation;
    g_return_val_if_fail (GTK_IS_WIDGET (gtk_widget), eel_irect_empty);

    gtk_widget_get_allocation (gtk_widget, &allocation);
    return eel_irect_assign (allocation.x,
                             allocation.y,
                             (int) allocation.width,
                             (int) allocation.height);
}

/**
 * eel_gtk_widget_get_dimensions:
 * @gtk_widget: The source GtkWidget.
 *
 * Return value: The widget's dimensions.  The returned dimensions are only valid
 *               after the widget's geometry has been "allocated" by its container.
 */
EelDimensions
eel_gtk_widget_get_dimensions (GtkWidget *gtk_widget)
{
    EelDimensions dimensions;
    GtkAllocation allocation;

    g_return_val_if_fail (GTK_IS_WIDGET (gtk_widget), eel_dimensions_empty);

    gtk_widget_get_allocation (gtk_widget, &allocation);
    dimensions.width = (int) allocation.width;
    dimensions.height = (int) allocation.height;

    return dimensions;
}

/**
 * eel_gtk_widget_get_preferred_dimensions:
 * @gtk_widget: The source GtkWidget.
 *
 * Return value: The widget's preferred dimensions.  The preferred dimensions are
 *               computed by calling the widget's 'size_request' method and thus
 *               could potentially be expensive for complicated widgets.
 */
EelDimensions
eel_gtk_widget_get_preferred_dimensions (GtkWidget *gtk_widget)
{
    GtkRequisition requisition;
    EelDimensions preferred_dimensions;

    g_return_val_if_fail (GTK_IS_WIDGET (gtk_widget), eel_dimensions_empty);

    gtk_widget_size_request (gtk_widget, &requisition);

    preferred_dimensions.width = (int) requisition.width;
    preferred_dimensions.height = (int) requisition.height;

    return preferred_dimensions;
}

/**
 * eel_gdk_window_clip_dirty_area_to_screen:
 * @gdk_window: The GdkWindow that the damage occured on.
 * @dirty_area: The dirty area as an EelIRect.
 *
 * Return value: An EelIRect of the dirty area clipped to the screen.
 *
 * This function is useful to do less work in expose_event() GtkWidget methods.
 * It also ensures that any drawing that the widget does is actually onscreen.
 */
EelIRect
eel_gdk_window_clip_dirty_area_to_screen (GdkWindow *gdk_window,
        EelIRect dirty_area)
{
    EelIRect clipped;
    EelDimensions screen_dimensions;
    EelIRect screen_relative_bounds;
    int dirty_width;
    int dirty_height;

    g_return_val_if_fail (gdk_window != NULL, eel_irect_empty);

    dirty_width = dirty_area.x1 - dirty_area.x0;
    dirty_height = dirty_area.y1 - dirty_area.y0;

    g_return_val_if_fail (dirty_width > 0, eel_irect_empty);
    g_return_val_if_fail (dirty_height > 0, eel_irect_empty);

    screen_dimensions = eel_screen_get_dimensions ();
    screen_relative_bounds = eel_gdk_window_get_screen_relative_bounds (gdk_window);

    /* Window is obscured by left edge of screen */
    if ((screen_relative_bounds.x0 + dirty_area.x0) < 0)
    {
        int clipped_width = screen_relative_bounds.x0 + dirty_area.x0 + dirty_width;
        clipped.x0 = dirty_area.x0 + dirty_width - clipped_width;
        clipped.x1 = clipped.x0 + clipped_width;
    }
    else
    {
        clipped.x0 = dirty_area.x0;
        clipped.x1 = clipped.x0 + dirty_width;
    }

    /* Window is obscured by right edge of screen */
    if (screen_relative_bounds.x1 > screen_dimensions.width)
    {
        int obscured_width;

        obscured_width =
            screen_relative_bounds.x0 + dirty_area.x0 + dirty_width - screen_dimensions.width;

        if (obscured_width > 0)
        {
            clipped.x1 -= obscured_width;
        }
    }

    /* Window is obscured by top edge of screen */
    if ((screen_relative_bounds.y0 + dirty_area.y0) < 0)
    {
        int clipped_height = screen_relative_bounds.y0 + dirty_area.y0 + dirty_height;
        clipped.y0 = dirty_area.y0 + dirty_height - clipped_height;
        clipped.y1 = clipped.y0 + clipped_height;
    }
    else
    {
        clipped.y0 = dirty_area.y0;
        clipped.y1 = clipped.y0 + dirty_height;
    }

    /* Window is obscured by bottom edge of screen */
    if (screen_relative_bounds.y1 > screen_dimensions.height)
    {
        int obscured_height;

        obscured_height =
            screen_relative_bounds.y0 + dirty_area.y0 + dirty_height - screen_dimensions.height;

        if (obscured_height > 0)
        {
            clipped.y1 -= obscured_height;
        }
    }

    if (eel_irect_is_empty (&clipped))
    {
        clipped = eel_irect_empty;
    }

    return clipped;
}

GdkRectangle
eel_irect_to_gdk_rectangle (EelIRect rectangle)
{
    GdkRectangle gdk_rect;

    gdk_rect.x = rectangle.x0;
    gdk_rect.y = rectangle.y0;
    gdk_rect.width = eel_irect_get_width (rectangle);
    gdk_rect.height = eel_irect_get_height (rectangle);

    return gdk_rect;
}

EelDimensions
eel_gdk_window_get_dimensions (GdkWindow *gdk_window)
{
    EelDimensions dimensions;

    g_return_val_if_fail (gdk_window != NULL, eel_dimensions_empty);

    dimensions.width = gdk_window_get_width(gdk_window);
    dimensions.height = gdk_window_get_height(gdk_window);

    return dimensions;
}

EelIPoint
eel_gdk_get_pointer_position (void)
{

    EelIPoint position;

    gdk_window_get_pointer (gdk_get_default_root_window (),
                            &position.x,
                            &position.y,
                            NULL);

    return position;
}
