/*!
 * Jquery Scroll Events 1.0.0 - jQuery plugin for special events related to
 * the scrolling action
 *
 * Require: jQuery 1.3.x
 * Author: Filipi Zimermann / James Padolsey
 * Email:  filipiz at gmail dot com
 * Licensed under the MIT license:
 *   http://www.opensource.org/licenses/mit-license.php
*/

var uid1 = 'D' + (+new Date());
var uid2 = 'D' + (+new Date() + 1);
var uid3 = 'D' + (+new Date() + 2);
var uid4 = 'D' + (+new Date() + 3);

jQuery.event.special.scrollstart = {
        setup: function() {
                var timer;
                var handler =  function(evt) {

                        var _self = this;
                        var _args = arguments;

                        if (timer) {
                                clearTimeout(timer);
                        } else {
                                evt.type = 'scrollstart';
                                jQuery.event.handle.apply(_self, _args);
                        }

                        timer = setTimeout( function(){
                                        timer = null;
                        }, jQuery.event.special.scrollstop.latency);

                };

                jQuery(this).bind('scroll', handler).data(uid1, handler);

        },

    teardown: function(namespaces) {
       jQuery(this).unbind('scroll', jQuery(this).data(uid1) );
    }
};



jQuery.event.special.scrollstop = {
        latency: 300,
        setup: function() {
                var timer;
                var handler = function(evt) {

                        var _self = this;
                        var _args = arguments;

                        if (timer) {
                                clearTimeout(timer);
                        }                              
                       
                        timer = setTimeout( function(){
                                        timer = null;
                                        evt.type = 'scrollstop';

                                        jQuery.event.handle.apply(_self, _args);
                        }, jQuery.event.special.scrollstop.latency);

                };

                jQuery(this).bind('scroll', handler).data(uid2, handler);

        },
       
        teardown: function() {
                jQuery(this).unbind('scroll', jQuery(this).data(uid2) );
        }
};



jQuery.event.special.scrollreachtop = {
    setup: function(data, namespaces) {
        jQuery(this).bind('scroll', jQuery.event.special.scrollreachtop.handler)
                        .data(uid3, jQuery.event.special.scrollreachtop.handler);
    },

    teardown: function(namespaces) {
        jQuery(this).unbind('scroll', jQuery(this).data(uid3) );
    },

    handler: function(evt) {
        evt.type = 'scrollreachtop';
        if (parseInt(jQuery(this).scrollTop()) == 0 )
                jQuery.event.handle.apply(this, arguments);
    }
};



jQuery.event.special.scrollreachbottom = {
    setup: function(data, namespaces) {
        jQuery(this).bind('scroll', jQuery.event.special.scrollreachbottom.handler)
                        .data(uid4, jQuery.event.special.scrollreachbottom.handler);
    },

    teardown: function(namespaces) {
        jQuery(this).unbind('scroll', jQuery(this).data(uid4) );
    },

    handler: function(evt) {
                evt.type = 'scrollreachbottom';
        var scrollMaxTop = parseInt(jQuery(this).attr('scrollHeight')) - parseInt(jQuery(this).innerHeight()) - 1;
        if (parseInt(jQuery(this).scrollTop()) >= scrollMaxTop )
                jQuery.event.handle.apply(this, arguments);
    }
};