(function($) {

$.fn.hoverscroll = function(params) {
	if (!params) { params = {}; }
	
	params = $.extend({}, $.fn.hoverscroll.params, params);
	
	this.each(function() {
		var $this = $(this);
		
		if (params.debug) {
			$.log('[HoverScroll] Trying to create hoverscroll on element ' + this.tagName + '#' + this.id);
		}

		$this.wrap('<div class="listcontainer" valign="middle"></div>');
		
		$this.addClass('list');

		var listctnr = $this.parent();

		listctnr.wrap('<div class="ui-widget-content hoverscroll" valign="middle"></div>');

		var ctnr = listctnr.parent();

		if (params.arrows) {
			if (!params.vertical) {
				listctnr.append('<div class="arrow left"></div>').append('<div class="arrow right"></div>')
			} else {
				listctnr.append('<div class="arrow top"></div>').append('<div class="arrow bottom"></div>')
			}
		}

		ctnr.width(params.width).height(params.height);
		listctnr.width(params.width).height(params.height);
		
		var size = 0;
		
		if (!params.vertical) {
			ctnr.addClass('horizontal');

			$this.children().each(function() {
				$(this).addClass('item');
				
				if ($(this).outerWidth) {
					size += $(this).outerWidth(true);
				} else {
					size += $(this).width() + parseInt($(this).css('padding-left')) + parseInt($(this).css('padding-right'))
						+ parseInt($(this).css('margin-left')) + parseInt($(this).css('margin-right'));
				}
                                
			});
                        //parte inserida por elizeu
			$this.width(size*1.05);
			
			if (params.debug) {
				$.log('[HoverScroll] Computed content width : ' + size + 'px');
			}
			if (ctnr.outerWidth) {
				size = ctnr.outerWidth();
			} else {
				size = ctnr.width() + parseInt(ctnr.css('padding-left')) + parseInt(ctnr.css('padding-right'))
					+ parseInt(ctnr.css('margin-left')) + parseInt(ctnr.css('margin-right'));
			}
			
			if (params.debug) {
				$.log('[HoverScroll] Computed container width : ' + size + 'px');
			}
		} else {
			ctnr.addClass('vertical');
			$this.children().each(function() {
				$(this).addClass('item')			
				if ($(this).outerHeight) {
					size += $(this).outerHeight(true);
				} else {
					size += $(this).height() + parseInt($(this).css('padding-top')) + parseInt($(this).css('padding-bottom'))
						+ parseInt($(this).css('margin-bottom')) + parseInt($(this).css('margin-bottom'));
				}
			});
			
			//parte inserida por elizeu
			$this.height(size*1.05);
			if (params.debug) {
				$.log('[HoverScroll] Computed content height : ' + size + 'px');
			}
			
			if (ctnr.outerHeight) {
				size = ctnr.outerHeight();
			} else {
				size = ctnr.height() + parseInt(ctnr.css('padding-top')) + parseInt(ctnr.css('padding-bottom'))
					+ parseInt(ctnr.css('margin-top')) + parseInt(ctnr.css('margin-bottom'));
			}
			
			if (params.debug) {
				$.log('[HoverScroll] Computed container height : ' + size + 'px');
			}
		}
		
		var zone = {
			1: { action: 'move', from: 0, to: 0.06 * size, direction: -1 , speed: 16 },
			2: { action: 'move', from: 0.06 * size, to: 0.15 * size, direction: -1 , speed: 8 },
			3: { action: 'move', from: 0.15 * size, to: 0.25 * size, direction: -1 , speed: 4 },
			4: { action: 'move', from: 0.25 * size, to: 0.4 * size, direction: -1 , speed: 2 },
			5: { action: 'stop', from: 0.4 * size, to: 0.6 * size },
			6: { action: 'move', from: 0.6 * size, to: 0.75 * size, direction: 1 , speed: 2 },
			7: { action: 'move', from: 0.75 * size, to: 0.85 * size, direction: 1 , speed: 4 },
			8: { action: 'move', from: 0.85 * size, to: 0.94 * size, direction: 1 , speed: 8 },
			9: { action: 'move', from: 0.94 * size, to: size, direction: 1 , speed: 16 }
		}

		ctnr[0].isChanging = false;
		ctnr[0].direction  = 0;
		ctnr[0].speed      = 1;

		function checkMouse(x, y) {
			x = x - ctnr.offset().left;
			y = y - ctnr.offset().top;
			
			var pos;
			if (!params.vertical) { pos = x; }
			else { pos = y; }
			
			for (i in zone) {
				if (pos >= zone[i].from && pos < zone[i].to) {
					if (zone[i].action == 'move') { startMoving(zone[i].direction, zone[i].speed); }
					else { stopMoving(); }
				}
			}
		}

		function setArrowOpacity() {
			if (!params.arrows) { return; }
			
			var maxScroll;
			var scroll;
			
			if (!params.vertical) {
				maxScroll = listctnr[0].scrollWidth - listctnr.width();
				scroll = listctnr[0].scrollLeft;
            } else {
				maxScroll = listctnr[0].scrollHeight - listctnr.height();
				scroll = listctnr[0].scrollTop;
			}
			
			var opacity = (scroll / maxScroll);
			var limit = params.arrowsOpacity;
			
			if (isNaN(opacity)) { opacity = 0; }

			var done = false;
			if (opacity <= 0) { $('div.arrow.left, div.arrow.top', ctnr).hide(); done = true; }
			if (opacity >= limit || maxScroll <= 0) { $('div.arrow.right, div.arrow.bottom', ctnr).hide(); done = true; }
			
			if (!done) {
				$('div.arrow.left, div.arrow.top', ctnr).show().css('opacity', (opacity > limit ? limit : opacity));
				$('div.arrow.right, div.arrow.bottom', ctnr).show().css('opacity', (1 - opacity > limit ? limit : 1 - opacity));
			}
		}
		
		function startMoving(direction, speed) {
			if (ctnr[0].direction != direction) {
				if (params.debug) {
					$.log('[HoverScroll] Starting to move. direction: ' + direction + ', speed: ' + speed);
				}
				
				stopMoving();
				ctnr[0].direction  = direction;
				ctnr[0].isChanging = true;
				move();
			}
			if (ctnr[0].speed != speed) {
				if (params.debug) {
					$.log('[HoverScroll] Changed speed: ' + speed);
				}
				
				ctnr[0].speed = speed;
			}
		}

		function stopMoving() {
			if (ctnr[0].isChanging) {
				if (params.debug) {
					$.log('[HoverScroll] Stoped moving');
				}
				
				ctnr[0].isChanging = false;
				ctnr[0].direction  = 0;
				ctnr[0].speed      = 1;
				clearTimeout(ctnr[0].timer);
			}
		}
		
		function move() {
			if (ctnr[0].isChanging == false) { return; }
			
			setArrowOpacity();
			
			var scrollSide;
			if (!params.vertical) { scrollSide = 'scrollLeft'; }
			else { scrollSide = 'scrollTop'; }
			
			listctnr[0][scrollSide] += ctnr[0].direction * ctnr[0].speed;
			ctnr[0].timer = setTimeout(function() { move(); }, 50);
		}

		ctnr

		.mousemove(function(e) { checkMouse(e.pageX, e.pageY); })

		.bind('mouseleave', function() { stopMoving(); });
		
		if (params.arrows) {
			setArrowOpacity();
		} else {
			$('.arrowleft, .arrowright, .arrowtop, .arrowbottom', ctnr).hide();
		}
	});
	
	return this;
};

if (!$.fn.offset) {
	$.fn.offset = function() {
		this.left = this.top = 0;
		
		if (this[0] && this[0].offsetParent) {
			var obj = this[0];
			do {
				this.left += obj.offsetLeft;
				this.top += obj.offsetTop;
			} while (obj = obj.offsetParent);
		}
		
		return this;
	}
}

$.fn.hoverscroll.params = {
	vertical:	false,
	width:		210,
	height:		49,
	arrows:		true,
	arrowsOpacity:	9.9,
	debug:		false
};

$.log = function(msg) {
	if (console && console.log) {
		console.log(msg);
	}
};

})(jQuery);