/*
 *  ReactOS kernel
 *  Copyright (C) 1998, 1999, 2000, 2001 ReactOS Team
 *
 *  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 2 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
/*
 * PROJECT:         ReactOS user32.dll
 * FILE:            win32ss/user/user32/windows/rect.c
 * PURPOSE:         Input
 * PROGRAMMER:      Casper S. Hornstrup (chorns@users.sourceforge.net)
 * UPDATE HISTORY:
 *      09-05-2001  CSH  Created
 */

#include <user32.h>

/*
 * @implemented
 */
BOOL
WINAPI
CopyRect(LPRECT lprcDst,
         CONST RECT *lprcSrc)
{
    if (lprcDst == NULL || lprcSrc == NULL)
        return FALSE;

    *lprcDst = *lprcSrc;

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
EqualRect(CONST RECT *lprc1,
          CONST RECT *lprc2)
{
    if (lprc1 == NULL || lprc2 == NULL)
        return FALSE;

    return (lprc1->left == lprc2->left) && (lprc1->top == lprc2->top) &&
           (lprc1->right == lprc2->right) && (lprc1->bottom == lprc2->bottom);
}


/*
 * @implemented
 */
BOOL
WINAPI
InflateRect(LPRECT rect,
            int dx,
            int dy)
{
    if (rect == NULL)
        return FALSE;

    rect->left -= dx;
    rect->top -= dy;
    rect->right += dx;
    rect->bottom += dy;

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
IntersectRect(LPRECT lprcDst,
              CONST RECT *lprcSrc1,
              CONST RECT *lprcSrc2)
{
    if (lprcDst == NULL || lprcSrc1 == NULL || lprcSrc2 == NULL)
        return FALSE;

    if (IsRectEmpty(lprcSrc1) || IsRectEmpty(lprcSrc2) ||
        lprcSrc1->left >= lprcSrc2->right ||
        lprcSrc2->left >= lprcSrc1->right ||
        lprcSrc1->top >= lprcSrc2->bottom ||
        lprcSrc2->top >= lprcSrc1->bottom)
    {
        SetRectEmpty(lprcDst);
        return FALSE;
    }

    lprcDst->left = max(lprcSrc1->left, lprcSrc2->left);
    lprcDst->right = min(lprcSrc1->right, lprcSrc2->right);
    lprcDst->top = max(lprcSrc1->top, lprcSrc2->top);
    lprcDst->bottom = min(lprcSrc1->bottom, lprcSrc2->bottom);

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
IsRectEmpty(CONST RECT *lprc)
{
    if (lprc == NULL)
        return TRUE;

    return ((lprc->left >= lprc->right) || (lprc->top >= lprc->bottom));
}


/*
 * @implemented
 */
BOOL
WINAPI
OffsetRect(LPRECT rect,
           int dx,
           int dy)
{
    if (rect == NULL)
        return FALSE;

    rect->left += dx;
    rect->top += dy;
    rect->right += dx;
    rect->bottom += dy;

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
PtInRect(CONST RECT *lprc,
         POINT pt)
{
    if (lprc == NULL)
        return FALSE;

    return((pt.x >= lprc->left) && (pt.x < lprc->right) &&
           (pt.y >= lprc->top) && (pt.y < lprc->bottom));
}

BOOL
WINAPI
SetRect(LPRECT lprc,
        int xLeft,
        int yTop,
        int xRight,
        int yBottom)
{
    if (lprc == NULL)
        return FALSE;

    lprc->left = xLeft;
    lprc->top = yTop;
    lprc->right = xRight;
    lprc->bottom = yBottom;

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
SetRectEmpty(LPRECT lprc)
{
    if (lprc == NULL)
        return FALSE;

    lprc->left = lprc->right = lprc->top = lprc->bottom = 0;

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
SubtractRect(LPRECT lprcDst,
             CONST RECT *lprcSrc1,
             CONST RECT *lprcSrc2)
{
    RECT tempRect;

    if (lprcDst == NULL || lprcSrc1 == NULL || lprcSrc2 == NULL)
        return FALSE;

    if (!IntersectRect(&tempRect, lprcSrc1, lprcSrc2))
    {
        *lprcDst = *lprcSrc1;
        return TRUE;
    }

    if (EqualRect(&tempRect, lprcSrc1))
    {
        SetRectEmpty(lprcDst);
        return FALSE;
    }

    *lprcDst = *lprcSrc1;

    if (lprcDst->top == tempRect.top && lprcDst->bottom == tempRect.bottom)
    {
        if (lprcDst->left == tempRect.left)
            lprcDst->left = tempRect.right;
        else if (lprcDst->right == tempRect.right)
            lprcDst->right = tempRect.left;
    }
    else if (lprcDst->left == tempRect.left && lprcDst->right == tempRect.right)
    {
        if (lprcDst->top == tempRect.top)
            lprcDst->top = tempRect.bottom;
        else if (lprcDst->bottom == tempRect.bottom)
            lprcDst->bottom = tempRect.top;
    }

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
UnionRect(LPRECT lprcDst,
          CONST RECT *lprcSrc1,
          CONST RECT *lprcSrc2)
{
    if (lprcDst == NULL || lprcSrc1 == NULL || lprcSrc2 == NULL)
        return FALSE;

    if (IsRectEmpty(lprcSrc1))
    {
        if (IsRectEmpty(lprcSrc2))
        {
            SetRectEmpty(lprcDst);
            return FALSE;
        }
        else
        {
            *lprcDst = *lprcSrc2;
        }
    }
    else
    {
        if (IsRectEmpty(lprcSrc2))
        {
            *lprcDst = *lprcSrc1;
        }
        else
        {
            lprcDst->left = min(lprcSrc1->left, lprcSrc2->left);
            lprcDst->top = min(lprcSrc1->top, lprcSrc2->top);
            lprcDst->right = max(lprcSrc1->right, lprcSrc2->right);
            lprcDst->bottom = max(lprcSrc1->bottom, lprcSrc2->bottom);
        }
    }

    return TRUE;
}