/* eel-art-extensions.c - implementation of libart extension functions.
 *
 *  Copyright (C) 2000 Eazel, Inc.
 *
 *  The Gnome 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 Gnome 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 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 the Gnome Library; see the file COPYING.LIB.  If not,
 *  see <http://www.gnu.org/licenses/>.
 *
 *  Authors: Darin Adler <darin@eazel.com>
 *           Ramiro Estrugo <ramiro@eazel.com>
 */

#include <config.h>

#include "eel-art-extensions.h"
#include "eel-lib-self-check-functions.h"
#include <math.h>

const EelDRect eel_drect_empty = { 0.0, 0.0, 0.0, 0.0 };
const EelIRect eel_irect_empty = { 0, 0, 0, 0 };

static void
eel_irect_copy (EelIRect       *dest,
                const EelIRect *src)
{
    dest->x0 = src->x0;
    dest->y0 = src->y0;
    dest->x1 = src->x1;
    dest->y1 = src->y1;
}

static gboolean
eel_irect_is_empty (const EelIRect *src)
{
    return (src->x1 <= src->x0 ||
            src->y1 <= src->y0);
}

void
eel_irect_union (EelIRect       *dest,
                 const EelIRect *src1,
                 const EelIRect *src2)
{
    if (eel_irect_is_empty (src1))
    {
        eel_irect_copy (dest, src2);
    }
    else if (eel_irect_is_empty (src2))
    {
        eel_irect_copy (dest, src1);
    }
    else
    {
        dest->x0 = MIN (src1->x0, src2->x0);
        dest->y0 = MIN (src1->y0, src2->y0);
        dest->x1 = MAX (src1->x1, src2->x1);
        dest->y1 = MAX (src1->y1, src2->y1);
    }
}

static void
eel_irect_intersect (EelIRect       *dest,
                     const EelIRect *src1,
                     const EelIRect *src2)
{
    dest->x0 = MAX (src1->x0, src2->x0);
    dest->y0 = MAX (src1->y0, src2->y0);
    dest->x1 = MIN (src1->x1, src2->x1);
    dest->y1 = MIN (src1->y1, src2->y1);
}

/**
 * eel_irect_get_width:
 *
 * @rectangle: An EelIRect.
 *
 * Returns: The width of the rectangle.
 *
 */
int
eel_irect_get_width (EelIRect rectangle)
{
    return rectangle.x1 - rectangle.x0;
}

/**
 * eel_irect_get_height:
 *
 * @rectangle: An EelIRect.
 *
 * Returns: The height of the rectangle.
 *
 */
int
eel_irect_get_height (EelIRect rectangle)
{
    return rectangle.y1 - rectangle.y0;
}


static void
eel_drect_copy (EelDRect       *dest,
                const EelDRect *src)
{
    dest->x0 = src->x0;
    dest->y0 = src->y0;
    dest->x1 = src->x1;
    dest->y1 = src->y1;
}

static gboolean
eel_drect_is_empty (const EelDRect *src)
{
    return (src->x1 <= src->x0 || src->y1 <= src->y0);
}

void
eel_drect_union (EelDRect       *dest,
                 const EelDRect *src1,
                 const EelDRect *src2)
{
    if (eel_drect_is_empty (src1))
    {
        eel_drect_copy (dest, src2);
    }
    else if (eel_drect_is_empty (src2))
    {
        eel_drect_copy (dest, src1);
    }
    else
    {
        dest->x0 = MIN (src1->x0, src2->x0);
        dest->y0 = MIN (src1->y0, src2->y0);
        dest->x1 = MAX (src1->x1, src2->x1);
        dest->y1 = MAX (src1->y1, src2->y1);
    }
}

gboolean
eel_irect_hits_irect (EelIRect rectangle_a,
                      EelIRect rectangle_b)
{
    EelIRect intersection;
    eel_irect_intersect (&intersection, &rectangle_a, &rectangle_b);
    return !eel_irect_is_empty (&intersection);
}

gboolean
eel_irect_equal (EelIRect rectangle_a,
                 EelIRect rectangle_b)
{
    return rectangle_a.x0 == rectangle_b.x0
           && rectangle_a.y0 == rectangle_b.y0
           && rectangle_a.x1 == rectangle_b.x1
           && rectangle_a.y1 == rectangle_b.y1;
}

EelIRect
eel_irect_offset_by (EelIRect rectangle,
                     int      x,
                     int      y)
{
    rectangle.x0 += x;
    rectangle.x1 += x;
    rectangle.y0 += y;
    rectangle.y1 += y;

    return rectangle;
}

EelIRect
eel_irect_scale_by (EelIRect rectangle,
                    double   scale)
{
    rectangle.x0 *= scale;
    rectangle.x1 *= scale;
    rectangle.y0 *= scale;
    rectangle.y1 *= scale;

    return rectangle;
}
