password-manager/frontend/beta/js/YUI-extensions/dd/ScrollManager.js

// kill dependency issue
if(YAHOO.util.DragDrop){
/**
 * @class YAHOO.ext.dd.ScrollManager
 * Provides automatic scrolling of overflow regions in the page during drag operations.<br><br>
 * <b>Note: This class uses "Point Mode" and is untested in "Intersect Mode".</b>
 * @singleton
 */
YAHOO.ext.dd.ScrollManager = function(){
    var ddm = YAHOO.util.DragDropMgr;
    var els = {};
    var dragEl = null;
    var proc = {};
    
    var onStop = function(e){
        dragEl = null;
        clearProc();
    };
    
    var triggerRefresh = function(){
        if(ddm.dragCurrent){
             ddm.refreshCache(ddm.dragCurrent.groups);
        }
    }
    
    var doScroll = function(){
        if(ddm.dragCurrent){
            var dds = YAHOO.ext.dd.ScrollManager;
            if(!dds.animate || !YAHOO.util.Scroll){
                if(proc.el.scroll(proc.dir, dds.increment)){
                    triggerRefresh();
                }
            }else{
                proc.el.scroll(proc.dir, dds.increment, true, dds.animDuration, triggerRefresh);
            }
        }
    };
    
    var clearProc = function(){
        if(proc.id){
            clearInterval(proc.id);
        }
        proc.id = 0;
        proc.el = null;
        proc.dir = '';
    };
    
    var startProc = function(el, dir){
        clearProc();
        proc.el = el;
        proc.dir = dir;
        proc.id = setInterval(doScroll, YAHOO.ext.dd.ScrollManager.frequency);
    };
    
    var onFire = function(e, isDrop){
        if(isDrop || !ddm.dragCurrent){ return; }
        var dds = YAHOO.ext.dd.ScrollManager;
        if(!dragEl || dragEl != ddm.dragCurrent){
            dragEl = ddm.dragCurrent;
            // refresh regions on drag start
            dds.refreshCache();
        }
        
        var xy = YAHOO.util.Event.getXY(e);
        var pt = new YAHOO.util.Point(xy[0], xy[1]);
        for(var id in els){
            var el = els[id], r = el._region;
            if(r.contains(pt) && el.isScrollable()){
                if(r.bottom - pt.y <= dds.thresh){
                    if(proc.el != el){
                        startProc(el, 'down');
                    }
                    return;
                }else if(r.right - pt.x <= dds.thresh){
                    if(proc.el != el){
                        startProc(el, 'left');
                    }
                    return;
                }else if(pt.y - r.top <= dds.thresh){
                    if(proc.el != el){
                        startProc(el, 'up');
                    }
                    return;
                }else if(pt.x - r.left <= dds.thresh){
                    if(proc.el != el){
                        startProc(el, 'right');
                    }
                    return;
                }
            }
        }
        clearProc();
    };
    
    ddm.fireEvents = ddm.fireEvents.createSequence(onFire, ddm);
    ddm.stopDrag = ddm.stopDrag.createSequence(onStop, ddm);
    
    return {
        /**
         * Registers new overflow element(s) to auto scroll
         * @param {String/HTMLElement/Element/Array} el The id of or the element to be scrolled or an array of either
         */
        register : function(el){
            if(el instanceof Array){
                for(var i = 0, len = el.length; i < len; i++) {
                	this.register(el[i]);
                }
            }else{
                el = getEl(el);
                els[el.id] = el;
            }
        },
        
        /**
         * Unregisters overflow element(s) so they are no longer scrolled
         * @param {String/HTMLElement/Element/Array} el The id of or the element to be removed or an array of either
         */
        unregister : function(el){
            if(el instanceof Array){
                for(var i = 0, len = el.length; i < len; i++) {
                	this.unregister(el[i]);
                }
            }else{
                el = getEl(el);
                delete els[el.id];
            }
        },
        
        /**
         * The number of pixels from the edge of a container the pointer needs to be to 
         * trigger scrolling (defaults to 25)
         * @type Number
         */
        thresh : 25,
        
        /**
         * The number of pixels to scroll in each scroll increment (defaults to 50)
         * @type Number
         */
        increment : 100,
        
        /**
         * The frequency of scrolls in milliseconds (defaults to 500)
         * @type Number
         */
        frequency : 500,
        
        /**
         * True to animate the scroll (defaults to true)
         * @type Boolean
         */
        animate: true,
        
        /**
         * The animation duration in seconds - 
         * MUST BE less than YAHOO.ext.dd.ScrollManager.frequency! (defaults to .4)
         * @type Number
         */
        animDuration: .4,
        
        /**
         * Manually trigger a cache refresh.
         */
        refreshCache : function(){
            for(var id in els){
                els[id]._region = els[id].getRegion();
            }
        }
    } 
}();
}