/**
 * @(#) $RCSfile: ScrollBarLoop.as,v $ $Revision: 1.5 $ $Date: 2003/03/21 07:10:06 $
 *
 * Copyright 2003 Orgdot AS. All Rights Reserved.
 * http://dev.swfit.com
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

/**
 * This loop controls the object that is to be scrolled.
 *
 * @author      Olaf Havnes
 * @version     $Revision: 1.5 $ $Date: 2003/03/21 07:10:06 $
 * @since       SWFIT1.0
 */


// We measure the delay every run - it might be user controlled:
dl = /:delay ne "" ? /:delay : DEFAULT_DELAY;

if (drag)
{
    if (scroll_horz)
    {
        if (/:change_mouse_x + pos_x < min_x) pos_x = min_x;
        else if (/:change_mouse_x + pos_x > max_x) pos_x = max_x;
        else pos_x += /:change_mouse_x;
    }
    else
    {
        if (/:change_mouse_y + pos_y < min_y) pos_y = min_y;
        else if (/:change_mouse_y + pos_y > max_y) pos_y = max_y;
        else pos_y += /:change_mouse_y;
    }
}
else
{
    pos_x = x0 - dl * (pos_x - x0) / (dl + 1);
    pos_y = y0 - dl * (pos_y - y0) / (dl + 1);
}

button._x = pxl ? int (pos_x) : pos_x;
button._y = pxl ? int (pos_y) : pos_y;

// Compute the leverage:
scroll_leverage = 0;

if (max_press) scroll_leverage = - lvrg;
else if (min_press) scroll_leverage = lvrg;
else if (drag && int (pos_x) != int (x0)) scroll_leverage = lvrg * scroll_spd * (x0 - pos_x) / background._width ;
else if (drag && int (pos_y) != int (y0)) scroll_leverage = lvrg * scroll_spd * (y0 - pos_y) / background._height;



// TODO:
if (txt_scroll)
{
    scroll_max = eval (scroll_object add ".maxscroll");

    // Do we hide the scrollbar if it is not needed ?
    if (hde_scroll) _visible = scroll_max > 1; 

    if (scroll_leverage != 0)
    {

        // do this once
        if (scroll_nmb eq "") scroll_nmb = eval (scroll_object add ".scroll");

        // What is the largest possible step to take ?
        scroll_step_max = background._height / 100.0;

        // Implement the number from the buttons
        scroll_step = - scroll_max * scroll_leverage;
        if (scroll_step < 0) 
        {
            if (scroll_step < - scroll_step_max) scroll_step = - scroll_step_max;
        }
        else if (scroll_step > scroll_step_max) scroll_step = scroll_step_max;

        // Check the bounding box
        if (scroll_nmb + scroll_step > scroll_max) scroll_nmb = scroll_max;
        else if (scroll_nmb + scroll_step < scroll_min) scroll_nmb = scroll_min;
        else scroll_nmb += scroll_step;

        set ( scroll_object add ".scroll", int (scroll_nmb) );
    }
}
else
{
    // TODO - symmetrical of the paragraph below. Leave it empty to all functions are resolved.
    if (scroll_horz)
    {
    }
    else if (scroll_leverage != 0)
    {
        // We measure the size of the scroll_object every run - the size might change 
        // during the lifetime of the scrollbar.
        scroll_height = _parent.scroll_height ne "" ? _parent.scroll_height : getProperty (scroll_object, _height);
        scroll_y = getProperty (scroll_object, _y);


        // Note the "no_scroll_size", that might be programmatically plotted from inside 
        // the scrollable object. It defaults to the size of the scroll background.
        no_scroll_size = _parent.no_scroll_size ne "" ? _parent.no_scroll_size : background._height;

        scroll_max = scroll_y0;
        scroll_min = scroll_y0 - scroll_height + no_scroll_size;

        // Do we hide the scrollbar if it is not needed ?
        if (hde_scroll) _visible = scroll_min <= 0;
        
        // What is the largest possible step to take ?
        scroll_step_max = background._height / 4;

        // We implement the number from the buttons
        scroll_step = scroll_leverage * scroll_height;
        if (scroll_step < 0) 
        {
            if (scroll_step < - scroll_step_max) scroll_step = - scroll_step_max;
        }
        else if (scroll_step > scroll_step_max) scroll_step = scroll_step_max;
        
        // Check the bounding box
        if (scroll_y + scroll_step > scroll_max) scroll_y = scroll_max;
        else if (scroll_y + scroll_step < scroll_min) scroll_y = scroll_min;
        else scroll_y += scroll_step;
        
        // We round off no matter what flag is set on the scroll button:
        if (scroll_step * scroll_step > snp )
        setProperty (scroll_object, _y, int (scroll_y) );
    }
}


// Have we been told globally to reset the scrollbar ?
if (/:reset_scroll)
{
    if (txt_scroll) set ( scroll_object add ".scroll", 1 );
    else setProperty (scroll_object, _y, scroll_y0 );
}