/**
******************************************************************************
*
* @file       rectangle.cpp
* @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
* @brief      
* @see        The GNU Public License (GPL) Version 3
* @defgroup   OPMapWidget
* @{
* 
*****************************************************************************/

/* 
* This program is free software; you can redistribute it and/or modify 
* it under the terms of the GNU General Public License as published by 
* the Free Software Foundation; either version 3 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 General Public License 
* for more details.
* 
* You should have received a copy of the GNU General Public License along 
* with this program; if not, write to the Free Software Foundation, Inc., 
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

#include "rectangle.h"

namespace internals {

Rectangle Rectangle::Empty=Rectangle();

Rectangle Rectangle::FromLTRB(int left, int top, int right, int bottom)
{
    return Rectangle(left,
                     top,
                     right - left,
                     bottom - top);
}

Rectangle Rectangle::Inflate(Rectangle rect, int x, int y)
{
    Rectangle r = rect;
    r.Inflate(x, y);
    return r;
}

Rectangle Rectangle::Intersect(Rectangle a, Rectangle b)
{
    int x1 = std::max(a.X(), b.X());
    int x2 = std::min(a.X() + a.Width(), b.X() + b.Width());
    int y1 = std::max(a.Y(), b.Y());
    int y2 = std::min(a.Y() + a.Height(), b.Y() + b.Height());

    if(x2 >= x1
            && y2 >= y1)
    {

        return  Rectangle(x1, y1, x2 - x1, y2 - y1);
    }
    return Rectangle::Empty;
}

Rectangle Rectangle::Union(const Rectangle &a,const Rectangle &b)
{
    int x1 = std::min(a.x, b.x);
    int x2 = std::max(a.x + a.width, b.x + b.width);
    int y1 = std::min(a.y, b.y);
    int y2 = std::max(a.y + a.height, b.y + b.height);

    return Rectangle(x1, y1, x2 - x1, y2 - y1);
}

bool operator==(Rectangle const& lhs,Rectangle const& rhs)
{
    return (lhs.x == rhs.x && lhs.y == rhs.y && lhs.width == rhs.width && lhs.height == rhs.height);
}

uint qHash(Rectangle const& rect)
{
    return (int) ((quint32) rect.x ^
                  (((quint32) rect.y << 13) | ((quint32) rect.y >> 19)) ^
                  (((quint32) rect.width << 26) | ((quint32) rect.width >>  6)) ^
                  (((quint32) rect.height <<  7) | ((quint32) rect.height >> 25)));
}

} // end of namespace internals
