/*!
 * jQuery JavaScript Library v1.4.2
 * http://jquery.com/
 *
 * Copyright 2010, John Resig
 * Dual licensed under the MIT or GPL Version 2 licenses.
 * http://jquery.org/license
 *
 * Includes Sizzle.js
 * http://sizzlejs.com/
 * Copyright 2010, The Dojo Foundation
 * Released under the MIT, BSD, and GPL Licenses.
 *
 * Date: Sat Feb 13 22:33:48 2010 -0500
 */
jQuery.fn.setScroll = function(_scroll,_scroll_up,_scroll_down,_scroll_bar){   
    this.each(function(){   
           
        var _bar_margin = 3;   
           
        //create scroll dom   
        var _scroll_control = jQuery('<div class="scroll_zone">').width(_scroll.width).css({'position':'absolute','float':'none',margin:0,padding:0}).css('background','url('+_scroll.img+')');   
        var _scroll_control_up = jQuery('<img class="scroll_down">').attr('src',_scroll_up.img).width(_scroll.width).css({'z-index':'1000','position':'absolute', 'top':'0','float':'none', margin:0,padding:0});   
        var _scroll_control_down = jQuery('<img class="scroll_down">').attr('src',_scroll_down.img).width(_scroll.width).css({'z-index':'1000','position':'absolute', 'bottom':'0','float':'none',margin:0,padding:0});   
        var _scroll_control_bar =  jQuery('<img class="scroll_bar">').attr('src',_scroll_bar.img).width(_scroll.width).css({'z-index':'1500','position':'absolute','float':'none',margin:0,padding:0,height:_scroll_bar.height+'px'}).css('top',_scroll_up.height+_bar_margin+'px');   
           
        _scroll_control.append(_scroll_control_up);   
        _scroll_control.append(_scroll_control_bar);   
        _scroll_control.append(_scroll_control_down);   
           
        var _oheight = jQuery(this).css('height').substring(0,jQuery(this).css('height').indexOf('px'));   
        var _owidth = jQuery(this).width();   
        var _ocontent = jQuery(this).html();   
           
        if(jQuery(this).attr('scrollHeight')<=_oheight) return;   
           
        var _content_zone = jQuery('<div>').html(_ocontent).css({ width:_owidth-10+'px',height:_oheight+'px',overflow:'hidden','float':'none',margin:0,padding:0});   
           
        jQuery(this).css({'overflow':'hidden'});   
        jQuery(this).empty().append(_content_zone).css({position:'relative'}).append(_scroll_control.css({left:_owidth-_scroll.width+'px',top:'0',height:_oheight+'px',margin:0,padding:0}));   
  
        //register drag event   
        jQuery(this).find('.scroll_bar')   
        .mousedown(   
            function(){   
                jQuery(document).mousemove(   
                    function(e){   
                      var _content = _content_zone.get(0);   
                      var lastProgress = _scroll_control_bar.attr('progress');   
                      _scroll_control_bar.attr('progress',e.pageY);   
                      var nowProgress = _scroll_control_bar.css('top');   
                      nowProgress = nowProgress.substring(0,nowProgress.indexOf('px'));   
                      nowProgress = Number(nowProgress) + Number(e.pageY-lastProgress);   
                      var preProgress = nowProgress/(_oheight-_scroll_up.height-_scroll_down.height-_scroll_bar.height-(2*_bar_margin));   
                      _content.scrollTop = ((_content.scrollHeight - _content.offsetHeight) * preProgress);   
                      if(nowProgress<(_scroll_up.height+_bar_margin) || nowProgress > (_oheight-(_scroll_down.height+_scroll_bar.height+_bar_margin))) return false;   
                      try{_scroll_control_bar.css('top',nowProgress+'px');}catch(e){}   
                      return false;   
                    }   
                );   
                return false;   
            }   
        )   
        .mouseout(   
            function(){   
                jQuery(document).mouseup(   
                    function(){   
                        jQuery(document).unbind('mousemove');   
                     }   
                )   
            }   
        )   
           
    });    
}